With Modernas COVID-19 sales on the backfoot following the switch to an endemic vaccine market, the Massachusetts-based biopharma is busy laying the groundwork for its next potential mRNA shot in respiratory syncytial virus (RSV). And despite a head start in the field by competitors GSK and Pfizer, Moderna remains confident that its vaccine candidate, mRNA-1345, will still have a niche to fill.
Moderna currently expects initial approvals of its RSV vaccine to start rolling in during the first half of 2024, the company said in a press release. In turn, the company is eyeing a potential U.S. launch in the fall, which would capitalize on its established commercial efforts in the seasonal COVID-19 immunization market, Moderna explained.
RSV is a seasonal cold virus, but one that can cause severe breathing problems and pneumonia in the elderly, the very young and the immunocompromised.
With mRNA-1345s potential approval, Moderna would be wading into a fierce vaccine war already brewing between GSK and Pfizer, which won historic nods for their own RSV shots last May and have both already been raking in sales.
That said, Modernas mRNA vaccineif approvedwould be the only shot on the market in a pre-filled syringe, which could offer a potential convenience edge over its competitors, the companys CEO, Stphane Bancel, said on a call with investors Thursday.
By removing preparation steps before administering its vaccine, Moderna is hoping to ease the burden on pharmacists and clinicians and potentially alleviate wait times for patients, too. The companys own research has found that the prefilled presentation of its shot was three to four times more efficient than vaccines requiring reconstitution, Moderna explained in its release.
As the company prepares for its expected RSV rollout, Modernas medical team has been working with pharmacies and hospital networks literally on a daily basis to help spread the word about its vaccine candidates safety and efficacy profile, as well as the potential benefits of its prefilled syringe formulation, Bancel said.
Meanwhile, the company also feels its data package should help level the playing field by supporting a parity recommendation from the CDCs Advisory Committee on Immunization Practices (ACIP) post-approval, Moderna president Stephen Hogue said on the investor call.
Although Moderna expects its RSV vaccine to be a key revenue contributor moving forward, the company has yet to release guidance around potential sales of mRNA-1345, the companys chief financial officer, Jamey Mock, said.
Moderna touched on its RSV launch plans as it reported $167 million in first-quarter sales for the year, down a whopping 91% from the $1.9 billion it generated over the same stretch in 2023 when the company was still profiting off delivered doses deferred from 2022.
Nevertheless, the sharp decline in COVID-19 vaccine sales was to be expected and Modernas sales haul for the quarter still managed to come out ahead of consensus expectations of $93 million, William Blair analysts Myles Minter and Sarah Schram wrote in a note to clients Thursday.
The analysts called the sales decline unsurprising thanks to the market shift from pandemic to endemic and declines in previously expected vaccination rates.
Further, Modernas reported net loss of $1.2 billion in the quarter proved less severe than expected, the William Blair team added, crediting Moderna for its cost-saving efforts and reduced operating expenses.
For the COVID-19 vaccine business, Moderna is now taking a regional approach, Bancel told investors. In the U.S., the company is working with public health officials, healthcare providers and pharmacies to increase vaccination coverage rates across the country, the CEO explained.
Over in Europe, meanwhile, the company is actively engaged in a 2024 tender program that could see Moderna deliver millions of doses annually for up to four years, Bancel added.
And as for the rest of the world, Moderna is overhauling its commercial teams to help prioritize markets that provide greater commercial focus and impact, he explained. Bancel pointed to the companys recent agreement to provide Brazil with 12.5 million doses of its COVID shot Spikevax in the second quarter as a prime example of that strategy.
Looking ahead, the company reaffirmed its expectation to generate roughly $4 billion in 2024. That sum will likely represent a low point for the company ahead of a planned return to growth in 2025, Modernas CFO Mock said.
Play Video
In a first-ever human clinical trial of four adult patients, an mRNA cancer vaccine developed at the University of Florida quickly reprogrammed the immune system to attack glioblastoma, the most aggressive and lethal brain tumor.
The results mirror those in 10 pet dog patients suffering from naturally occurring brain tumors whose owners approved of their participation, as they had no other treatment options, as well as results from preclinical mouse models. The breakthrough now will be tested in a Phase 1 pediatric clinical trial for brain cancer.
Reported May 1 in the journal Cell, the discovery represents a potential new way to recruit the immune system to fight notoriously treatment-resistant cancers using an iteration of mRNA technology and lipid nanoparticles, similar to COVID-19 vaccines, but with two key differences: use of a patients own tumor cells to create a personalized vaccine, and a newly engineered complex delivery mechanism within the vaccine.
Instead of us injecting single particles, were injecting clusters of particles that are wrapping around each other like onions, like a bag full of onions, said senior author Elias Sayour, M.D., Ph.D., a UF Health pediatric oncologist who pioneered the new vaccine, which like other immunotherapies attempts to educate the immune system that a tumor is foreign. And the reason weve done that in the context of cancer is these clusters alert the immune system in a much more profound way than single particles would.
Among the most impressive findings was how quickly the new method, delivered intravenously, spurred a vigorous immune-system response to reject the tumor, said Sayour, principal investigator of the RNA Engineering Laboratory within UFs Preston A. Wells Jr. Center for Brain Tumor Therapy and a UF Health Cancer Center and McKnight Brain Institute investigator who led the multi-institution research team.
In less than 48 hours, we could see these tumors shifting from what we refer to as cold immune cold, very few immune cells, very silenced immune response to hot, very active immune response, he said. That was very surprising given how quick this happened, and what that told us is we were able to activate the early part of the immune system very rapidly against these cancers, and thats critical to unlock the later effects of the immune response.
Glioblastoma is among the most devastating diagnoses, with median survival around 15 months. Current standard of care involves surgery, radiation and some combination of chemotherapy.
The new publication is the culmination of promising translational results over seven years of studies, starting in preclinical mouse models and then in a clinical trial of 10 pet dogs that had spontaneously developed terminal brain cancer and had no other treatment options. That trial was conducted with owners consent in collaboration with the UF College of Veterinary Medicine. Dogs offer a naturally occurring model for malignant glioma because they are the only other species that develops spontaneous brain tumors with some frequency, said Sheila Carrera-Justiz, D.V.M., a veterinary neurologist at the UF College of Veterinary Medicine who is partnering with Sayour on the clinical trials. Gliomas in dogs are universally terminal, she said.
After treating pet dogs that had spontaneously developed brain cancer with personalized mRNA vaccines, Sayours team advanced the research to a small Food and Drug Administration-approved clinical trial designed to ensure safety and test feasibility before expanding to a larger trial.
In a cohort of four patients, genetic material called RNA was extracted from each patients own surgically removed tumor, and then messenger RNA, or mRNA the blueprint of what is inside every cell, including tumor cells was amplified and wrapped in the newly designed high-tech packaging of biocompatible lipid nanoparticles, to make tumor cells look like a dangerous virus when reinjected into the bloodstream and prompt an immune-system response. The vaccine was personalized to each patient with a goal of getting the most out of their unique immune system.
The demonstration that making an mRNA cancer vaccine in this fashion generates similar and strong responses across mice, pet dogs that have developed cancer spontaneously and human patients with brain cancer is a really important finding, because oftentimes we dont know how well the preclinical studies in animals are going to translate into similar responses in patients, said Duane Mitchell, M.D., Ph.D., director of the UF Clinical and Translational Science Institute and the UF Brain Tumor Immunotherapy Program and a co-author of the paper. And while mRNA vaccines and therapeutics are certainly a hot topic since the COVID pandemic, this is a novel and unique way of delivering the mRNA to generate these really significant and rapid immune responses that were seeing across animals and humans.
While too early in the trial to assess the clinical effects of the vaccine, the patients either lived disease-free longer than expected or survived longer than expected.
The 10 pet dogs lived a median of 139 days, compared with a median survival of 30 to 60 days typical for dogs with the condition.
The next step, through support from the Food and Drug Administration and the CureSearch for Childrens Cancer foundation, will be an expanded Phase I clinical trial to include up to 24 adult and pediatric patients to validate the findings. Once an optimal and safe dose is confirmed, an estimated 25 children would participate in Phase 2, said Sayour, an associate professor in the Lillian S. Wells Department of Neurosurgery and the department of pediatrics in the UF College of Medicine, part of UF Health.
For the new clinical trial, Sayours lab will partner with a multi-institution consortium, the Pediatric Neuro-Oncology Consortium, to send the immunotherapy treatment to childrens hospitals across the country. They will do this by receiving an individual patients tumor, manufacturing the personalized vaccine at UF and sending it back to the patients medical team, said Sayour, co-leader of the Immuno-Oncology and Microbiome research program at the UF Health Cancer Center.
Despite the promising results, the authors said one limitation is continued uncertainty about how best to harness the immune system while minimizing the potential for adverse side effects.
I am hopeful that this could be a new paradigm for how we treat patients, a new platform technology for how we can modulate the immune system, said Sayour, the Stop Children's Cancer/Bonnie R. Freeman Professor for Pediatric Oncology Research. I am hopeful for how this could now synergize with other immunotherapies and perhaps unlock those immunotherapies. We showed in this paper that you actually can have synergy with other types of immunotherapies, so maybe now we can have a combination approach of immunotherapy.
Sayour and Mitchell hold patents related to the vaccine which are under option to license by iOncologi Inc., a biotech company born as a spin out from UF in which Mitchell holds interest.
AstraZeneca, the company that sold the vaccination in India, acknowledged in court a day ago that the Covid injection can have an uncommon side effect. As a result, the parents of the woman who is said to have died after taking the vaccine have chosen to sue Serum Institute of India (SII). With the revelation of AstraZeneca's admission, the parents are optimistic of justice. The multinational pharmaceutical company is facing legal action from a class-action lawsuit alleging that the Covid-19 vaccine, which it co-developed with the University of Oxford, resulted in fatalities and severe injuries, including thrombosis with thrombocytopenia syndrome (TTS), a dangerous side effect that lowers platelet counts and causes blood clots. Karunya, the daughter of Venugopalan Govindan, passed away in July 2021 following her Covishield vaccination. Nonetheless, the government-appointed national committee found insufficient evidence to draw the conclusion that the vaccine was the cause of her death. This is the result of AstraZeneca's admission in court documents that a rare adverse effect of their vaccination could be reduced platelet count and blood clotting. AstraZeneca is being sued in a class-action case in the UK.
Expand
Whooping cough might sound like a Victorian disease, but the bacterial infection has made a dramatic comeback in recent months across Europe, Asia, and America.
The 100-day cough known clinically as pertussis infects the lungs and respiratory system, causing severe coughing fits and flu-like symptoms that can persist for months.
Complications are particularly severe in infants under six months, where the infection can develop into pneumonia, seizures and, in some cases, death. Babies who survive may have long-term neurological or lung damage.
Whooping cough is cyclical and naturally peaks every three-to-five years. It is also endemic to all regions of the planet, according to the World Health Organization (WHO), meaning it occurs naturally in populations.
A jab developed in the 1950s helped to almost eliminate the disease in Britain.
But a steady decline in vaccine uptake coupled with a resurgence of respiratory diseases following Covid lockdowns have contributed to rapidly rising case numbers with this year the worst on record since the mid-1980s.
In January and February alone, England recorded 1,468 cases compared to just 823 for the whole of 2023.
In the Czech Republic, cases are so widespread that criminal charges were filed against Pragues mayor, accusing him of allowing the infection to spread through reckless public health decisions. So far, the country has seen over 6,300 infections since January, and at least three infant deaths.
Parts of Asia are also struggling to contain the disease. In the Philippines, 54 babies have died this year, whilst in China, 30,000 have come down with the infection since January.
This outbreak is huge, and its not dissimilar to what we saw 40 years ago, explained Dr Paul Hunter, Professor of Medicine at the University of East Anglia.
When Covid hit, a lot of vaccination rates fell which is certainly contributing to what were seeing now worldwide, he said.
Health systems worldwide fell behind on routine jabs for preventable diseases during the Covid-19 years, with the largest sustained decline in childhood vaccinations in over three decades.
During that time, the WHO estimated around 25 million children missed out on doses of the pertussis vaccine, which is combined with the jab for polio, diphtheria, and hepatitis B in the UK.
Immunisation rates are still struggling to catch up, allowing communicable diseases to spread more quickly through populations. For instance, cases of measles have soared across the world to the point where more than half the planet is at high risk of an outbreak.
Another key problem is that vaccination uptake is steadily declining in pregnant women. If you vaccinate the mother, you protect the baby and they are the ones most at risk, said Dr Hunter.
Pregnant women need to be vaccinated to protect their newborns against whooping cough, because they cannot be jabbed themselves until they are two months old.
Mothers pass antibodies to their infants via the placenta, which in turn bridges the critical protection gap between birth and eight weeks the time when a child is most vulnerable to serious illness.
Babies born to women vaccinated at least a week before birth have a 91 per cent reduced risk of becoming ill with whooping cough in their first weeks of life, compared to babies whose mothers have not been vaccinated, according to the NHS.
But vaccine hesitancy influenced in part by disinformation on social media has meant uptake has fallen dramatically over the past ten or so years.
In Britain, around 70 per cent of pregnant women were jabbed for pertussis in 2017. But by 2023, that number dropped to around 58 per cent, according to the UK Health Security Agency.
Another key change, says Dr. Hunter, is the shift in the early 2010s from a whole-cell to an acellular vaccine for whooping cough.
In the past, pertussis vaccines were made using whole, inactivated Bordetella pertussis bacteria. These vaccines were highly effective but had some adverse side effects, including fever, mild allergic reactions, and in a very small number of babies, neurological damage although there is debate over whether the jab was responsible.
Starting in the early 2010s, many countries, including Britain, transitioned to using acellular pertussis vaccines. These jabs contain only specific proteins of the Bordetella pertussis bacterium. They cause fewer side effects, whilst still providing protection although it is slightly less effective.
There is certainly a view that, in part, the change in vaccine can explain the slight rise in cases beginning in the early 2010s, and could be playing a role in the current outbreaks, explained Dr Hunter.
Much is still to be understood about why whooping cough is on the rise this might be a one-off, and we could return to pre-Covid levels of the disease. But its also plausible that this is the future and that pertussis is here to stay, he added.
Protect yourself and your family by learning more about Global Health Security
Let me start with a disclaimer: The subject of todays newsletter will make some readers uncomfortable. It makes me a little uncomfortable.
The Times has just published an article about Americans who believe they suffered serious side effects from a Covid vaccine. More than 13,000 of them have filed vaccine-injury claims with the federal government.
My colleague Apoorva Mandavilli tells some of their stories in the article, including those of several people who work in medicine and science:
Ilka Warshawsky, a 58-year-old pathologist, said she lost all hearing in her right ear shortly after receiving a Covid booster shot.
Dr. Gregory Poland, 68 no less than the editor in chief of Vaccine, a scientific journal said that a loud whooshing sound in his ears had accompanied every moment since his first Covid shot.
Shaun Barcavage, 54, a nurse practitioner in New York City, has experienced a ringing sound in his ears, a racing heart and pain in his eyes, mouth and genitals for more than three years. I cant get the government to help me, Barcavage said. I am told Im not real.
This subject is uncomfortable because it feeds into false stories about the Covid vaccines that many Americans have come to believe namely, that the vaccines are ineffective or have side effects that exceed their benefits. Robert F. Kennedy Jr., the independent presidential candidate, has promoted these stories, as have some Republican politicians and conservative media figures. The scale of misinformation, Dr. Joshua Sharfstein of Johns Hopkins University told Apoorva, is staggering.
So let me be clear: The benefits of the Covid vaccines have far outweighed the downsides, according to a voluminous amount of data and scientific studies from around the world. In the U.S. alone, the vaccines have saved at least several hundred thousand lives and perhaps more than one million, studies estimate. Rates of death, hospitalization and serious illness have all been much higher among the unvaccinated than the vaccinated.
Here is data from the C.D.C., in a chart by my colleague Ashley Wu:
Not only are the vaccines benefits enormous, but the true toll of the side effects may be lower than the perceived toll: Experts told Apoorva that some people who believe Covid vaccines have harmed them are probably wrong about the cause of their problems.
We are having trouble retrieving the article content.
Please enable JavaScript in your browser settings.
Thank you for your patience while we verify access. If you are in Reader mode please exit andlog intoyour Times account, orsubscribefor all of The Times.
Thank you for your patience while we verify access.
Already a subscriber?Log in.
Want all of The Times?Subscribe.
By Cassidy Morrison Senior Health Reporter For Dailymail.Com 16:12 03 May 2024, updated 17:35 03 May 2024
Americans who claim they were badly injured by the Covid vaccines feel they are being ignored and gaslighted by the government.
Over 13,000 formal complaints about adverse reactions to the shots have been filedsince 2021 - but only 19 percent have been reviewed.
And just 12 patients have been compensated at an average of about $3,600, a figure which some have called insultingly low given the debilitating health issues they have been left with.
Experts say that researchers who've tried to investigate the little-understood side effect profile of Covid vaccines have been blocked by government officials and scientists who fear that even entertaining the possibility that vaccines can cause harm would fuel the anti-vax, which become bigger and louder during the pandemic.
Still, people are suffering from a range of conditions that came on soon after getting their first shot, including brain damage, tinnitus, neurological syndromes, facial paralysis, heart trouble, and shingles.
Unlike several countries like Australia, Canada, and Denmark, which have centralized health records compiled on a single database, the US has no such thing, leaving scientists to sift through reports of mild to severe side effects, of which there are more than four million lodged to the CDCs voluntary adverse reporting website.
Before Michelle Zimmerman, 37, had to say goodbye to her career as a neuroscientist, her regular 20-mile bike rides, and her lectures on the latest in AI, she had received the Johnson & Johnson vaccine in 2021.
No longer able to stand up on her own for long periods of time, and eventually diagnosed with brain damage, Dr Zimmerman had to move back in with her parents. She is convinced the vaccine she got came from a contaminated batch.
She told the New York Times: When I let myself think about the devastation of what this has done to my life, and how much Ive lost, sometimes it feels even too hard to comprehend.
Dr Zimmerman submitted her application for the Covid vaccine compensation program in October 2021, but it took two years for that claim to be acknowledged by the federal government. She has yet to receive any help from government officials.
She is far from the only one who has submitted such a claim. The Health Resources and Services Administrations Countermeasures Injury Compensation Program (CICP), 13,116 claims have been filed, of which more than 10,000 are still in review.
Twelve claims have been compensated at an average of about $3,600. This is because the office recognizes so few side effects as stemming from the Covid vaccine.
Shaun Barcavage, a 54-year-old nurse practitioner in New York, said that merely standing up would make his heart race ever since he got his first Covid shot.
His symptoms suggested postural orthostatic tachycardia syndrome (POTS), a condition in which the body cannot regulate the flow of blood properly, causing lightheadedness, fainting, and rapid heartbeat.
POTS has been tenuously linked to the vaccines, but more often with Covid infection itself.
Mr Barcavage, who in his career has worked on clinical trials for both HIV and Covid, said: I cant get the government to help me. I am told Im not real. Im told Im rare. Im told Im coincidence.
And Dr Gregory Poland, 68, who edits the journal Vaccine, has had a loud whoosing sound in his ears accompany every single second since he got his shot, and now fears never having a silent moment again.
His colleagues at the CDC did not take on his pleas for further research into the post-vaccine phenomenon.
Covid vaccines from Pfizer and BioNTech as well as Johnson and Johnson which is no longer available have been credited with averted at least three million deaths in the US and around 20 million globally due to the virus.
But even the best vaccines are not perfect, and when given to more than 270 million Americans in nearly 677 million doses, adverse reactions are bound to crop up.
Scientists fear the minority of vaccine recipients who have experienced severe reactions that have upended their lives are being ignored by federal officials with the power to initiate and fund more research into the matter.
DrAkiko Iwasaki, an immunologist and vaccine expert at Yale University, said: 'At least long Covid has been somewhat recognized', added people complaining of post-vaccine injuries are 'just completely ignored and dismissed and gaslighted.'
Dr Janet Woodcock, who headed the FDA from January 2021 through February 2022 during a crucial time which which early vaccines and treatments were being reviewed, told the New York Times that she wished government officials would hear those people out.
She said: I feel bad for those people. I believe their suffering should be acknowledged, that they have real problems, and they should be taken seriously.
Im disappointed in myself. I did a lot of things I feel very good about, but this is one of the few things I feel I just didnt bring it home.
The understaffed office heading the complaints database has left suffering Americans feeling let down by what was meant to be a highly specific, high efficient means of recourse for Covid shot recipients.
Renee France, 49 of Seattle, developed a form of facial paralysis called Bells palsy causing one side of her face to droop, which can be a reaction to a viral infection as well as the flu vaccine. She also developed shingles that caused a severe rash that crossed her face and debilitated her for weeks.
She submitted her claim to the database two times but heard nothing back. Like many other patients, her doctor dismissed her fears that the symptoms were side effects of her Covid shot. People have complained of being brushed off and labeled anti-vax by family and friends, despite their support for vaccines.
Dr. Buddy Creech, 50, who led several Covid vaccine trials at Vanderbilt University and suffered tinnitus and racing heartbeat for about a week after each shot, said: When our patients experience a side effect that may or may not be related to the vaccine, we owe it to them to investigate that as completely as we can.
Countries that store patient data in a single place have conducted more extensive research into side effects simply because they can spot them easier.
The CDCs adverse events reporting system is voluntary, so anyone can file a report, and the reports are not verified by the agency as being true or unbiased.
In addition to poring over the CDC system, researchers have to sift through insurance claims, and even then there are gaps.
Shots given at mass vaccination sites that cropped up in parking lots across the country did not file vaccine claims with insurers.
Rebecca Chandler, a vaccine safety expert at the Coalition for Epidemic Preparedness Innovations, said: Its harder to see signals when you have so many people, and things are happening in different parts of the country, and theyre not all collected in the same system.
But in China, Europe, and Israel, scientists have actively sought out instances of adverse reactions, even mild ones, in order to study them further.
Patients with the condition appear to suffer from symptoms similar to 'Long Covid' - including persistent headaches, intense tiredness and abnormal heart rate and blood pressure.
The European Medicines Agency has uncovered and linked facial paralysis and numbness to the Pfizer and Moderna shots, which the US has not, despite there being nearly 3,000 reports of facial paralysis on the CDCs voluntary database.
And Israeli authorities were first to spot an unusual side effect in April 2021 primarily among young men after a second dose of a Pfizer or Moderna shot inflammation of the heart muscle, also known as myocarditis.
Meanwhile, the CDC maintained there was no strong link between heart inflammation and Covid vaccines. That continued until the agency decided the following May to investigate a smattering of reports of heart inflammation in teenagers that occurred just a few days after they got a dose of the Pfizer or Moderna vaccines.
But despite the 16,700 reports of tinnitus, the 9,000 reports of vertigo, the 7,000 reports of irregularly fast heart beat, the 3,800 reports of Bells palsy, or any of the other millions of adverse event reports submitted to the CDCs system, the NIH is not conducting thorough research into the matter.
Dr William Murphy, a cancer researcher of 12 years at the NIH who has been pushing for these investigations, said that officials told him the same hackneyed phrase he had been hearing for years: the virus is worse.
He said: Yes, the virus is worse, but that doesnt obviate doing research to make sure that there may be other options.
In the first half of 2023, COVID-19 killed 42,670 people in the United States, while the flu killed about half that amount. Yet half as many people received the updated COVID booster as those who got the flu shot even though COVID is twice as deadly as influenza.
In all, around 22% of people have received the new COVID booster, while 47% of people have had a flu vaccine. Experts said much of that COVID-shot resistance is due to the continued polarizing nature of the pandemic and of the COVID vaccine, which has been shown to reduce the risk for long COVID as well as serious acute viral infections and deaths.
"COVID shots are controversial and polarizing, whereas flu shots (for the most part) are not. The decision to get or not get a flu shot is made calmly," said Peter M. Sandman, PhD, an expert in risk communication who writes about COVID risks and our responses to them.
It is also true that the likelihood of vaccination depends on your political leanings. An August 2023 study published in the journal Cureus found that even after controlling for alternative explanations to vaccine hesitancy, "there was a statistically significant relationship between the percentage of Republican supporters and rates of vaccine hesitancy." It's made vaccination against COVID much harder than for other vaccinations.
Complacency is also a factor, said Cameron R. Wolfe, MD, an infectious disease specialist and professor of medicine at Duke University of School of Medicine, in Durham, North Carolina. While COVID is still quite deadly, killing 42,670 Americans in the first 6 months of 2023, it's one fifth what it was in 2021 when the infection killed 219,222 people in the first half of the year.
Many young and middle-aged adults have experienced mild cases of COVID and aren't as fearful as they should be of the mortality numbers, said Wolfe. What's more, COVID deaths aren't being reported or highlighted in the media as often as they were in the first 2 years of the pandemic because the number of cases declined, and restrictions were lifted.
"Much of the mortality is happening out of sight these days compared to what was going on in 2020 and 2021," Wolfe said. "During that time, nearly everyone was directly impacted or knew someone who was impacted by COVID."
Pandemic fatigue has also played a role in our complacency. "There was this collective trauma around the death, disease, and lockdowns," said Ziyad Al-Aly, MD, a global expert on long COVID and chief of research and development at the VA Saint Louis Health Care System. "It was a devastating experience that people just want to forget."
Public health messaging is also to blame for the lower-than-normal COVID vaccine rates, said Al-Aly. Patients need to better understand that the role of the vaccine isn't to completely prevent COVID but to reduce the likelihood of hospitalization and death, similar to that of a flu shot. By reducing the risk for severe disease, the vaccine also reduces the risk for long COVID, a debilitating condition that's still poorly understood, has no cure, and has already caused thousands of American deaths, he said.
Botched public health messaging also allowed for misinformation to run rampant. Rare adverse events associated with the COVID vaccine have been severely overplayed and spread like wildfire on social media.
"Patients need to know that like any vaccine, vaccine injury does occur, but these vaccines have a better safety profile than almost any others," Al-Aly said. "The rewards of getting the vaccine far outweigh the risks, and patients need to understand that."
Normalizing COVID vaccination in the same way that health specialists and doctors have done with the flu shot will do a lot to increase vaccine numbers.
"[With the flu vaccine you] aren't hearing a lot of expert disagreement or nonexpert rumors about the vaccine or about the disease. The messaging every year is pretty consistent," Sandman said.
Reshaping beliefs will likely fall on physicians who are often much more trusted by their patients than the Centers for Disease Control and Prevention and other public health authorities. When physicians take the time to talk with their patients about the benefits of getting the vaccine, they can start to change minds, said Shivanjali Shankaran, MD, an infectious disease specialist at RUSH University Medical Center in Chicago.
"It might not happen in one 3-minute conversation, but over time, we need to help patients understand that the safety profile of these vaccines is really good, and even for those who don't fear acute COVID, the vaccine reduces the likelihood of chronic illness," Shankaran said.
The hope is that in time, people will accept the COVID vaccine as they do the flu shot and understand that it's really not a booster but a shot taken periodically or even annually to protect them against a disease that can still do a lot of damage, said Shankaran.
"The COVID vaccine needs to be discussed as part of our preventative healthcare routine like getting a flu shot or a colonoscopy," Shankaran said.
Fewer than one-third of women with HIV who were pregnant got recommended routine vaccinations, according to a multicenter cohort study.
Among 310 pregnancies in women living with HIV, the tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccine was administered to 32.6%, influenza vaccine to 31.6%, and both vaccines to 22.6%, Saba Berhie, MD, of Brigham and Women's Hospital in Boston, and colleagues reported in JAMA Network Open.
The authors characterized these rates as low. "Identifying and addressing barriers to vaccination receipt is urgently needed for pregnant people with HIV," they wrote.
The CDC recommends all women receive Tdap during week 27-36 of each pregnancy, preferably earlier during this window. Because women who are pregnant and their infants are at increased risk for influenza-related illness and death, the CDC recommends the influenza vaccine for all pregnant persons. The flu vaccine can be given during any trimester of pregnancy but should be a flu shot rather than a live attenuated influenza vaccine (LAIV, or nasal spray).
Adherence to those recommendations is suboptimal overall, even in women without HIV. According to recent data from the CDC, about 47% of women received influenza vaccination before or during pregnancy, and about 55% of women with a recent live birth received Tdap vaccination during pregnancy. In that study, there was a substantial increase in vaccine uptake among women whose provider recommended vaccination.
"Counseling about and receiving antenatal vaccinations are of utmost importance for all pregnant people, especially those with immunocompromising comorbidities like HIV," Berhie and colleagues wrote.
Some data suggest that people living with HIV have a poorer immune response to vaccination than those without the disease, the authors noted, while emphasizing that "no risks have been revealed and vaccination continues to be the standard of care in this population."
Consistent with prior studies, the researchers found that prior pregnancy impacted vaccination rates. Receipt of the flu vaccine was lower among multiparous women with HIV versus those who had never given birth (adjusted risk ratio [aRR] 0.57, 95% CI 0.39-0.83, P=0.004), while the relationship was less pronounced for Tdap.
Also, pregnancies of multiparous individuals with HIV were associated with a nonsignificant trend for lower likelihood of receiving both the Tdap and influenza vaccines (aRR 0.59, 95% CI 0.35-1.00, P=0.05).
Overall, vaccination during pregnancy was less frequent in participants who were younger, multiparous, had low income, or had perinatally acquired HIV, but these differences did not reach statistical significance.
The Surveillance Monitoring for ART Toxicities (SMARTT) study is an ongoing study evaluating safety of antiretroviral treatment in pregnancy and early childhood. The Women's Health Study (WHS) was a nested substudy of SMARTT that evaluated the health of pregnant and nonpregnant women with HIV. Berhie's analysis included a total of 278 women with 310 pregnancies with vaccination data available between December 2017 and July 2019.
When compared to women in the WHS that were excluded from this analysis due to missing vaccination data, included women were more likely to be high school graduates (79% vs 70%) and nulliparous (28% vs 17%). They were also more likely to have acquired HIV perinatally (21% vs 12%) and less likely to have comorbidities (27% vs 33%).
Of the women included in the final analysis, 77% identified as Black and 25% as Hispanic. Mean age at conception was 29.5 years. Most women (69%) had initiated prenatal care by the end of the first trimester of pregnancy.
The authors pointed out that reasons why pregnant women with HIV did not get vaccinated was not determined in this study. However, inadequate clinician recommendation for vaccination, vaccine hesitancy or refusal, and barriers to healthcare access might have contributed to the poor vaccine uptake.
Even though participants were enrolled prospectively, medical record data was reviewed retrospectively and may have underestimated vaccination rates. On the other hand, the study population might have been more engaged with the healthcare system and potentially have higher vaccination rates than the HIV community as a whole, the authors conjectured.
Katherine Kahn is a staff writer at MedPage Today, covering the infectious diseases beat. She has been a medical writer for over 15 years.
Disclosures
The study was funded by several institutes and centers of the National Institutes of Health.
Berhie and other study authors reported no relevant financial disclosures.
Primary Source
JAMA Network Open
Source Reference: Berhie S, et al "Routine vaccination during pregnancy among people living with HIV in the United States" JAMA Netw Open 2024; DOI: 10.1001/jamanetworkopen.2024.9531.
OV delivery of GP33 to solid tumor cells redirect the activity and cytotoxicity of P14 T cells in vitro
The vesicular stomatitis virus (VSV) is a potential oncolytic viral vector.30 In order to reduce neurotoxicity while retaining the lytic potency and wide-ranging tumor tropism of VSV,31,32,33 the G protein of VSV was replaced with the G protein of Lymphocytic Choriomeningitis Virus (LCMV), and the modified recombinant virus was named rVSV-LCMVG (Fig. 1a). Electron microscopy showed that rVSV-LCMVG maintained the original bullet-shaped particles, and the expression of viral proteins VSV-N, VSV-P, and VSV-M was detectable in anti-VSV-Rat serum, and the presence of LCMVG protein could be detected using anti-LCMVG monoclonal antibodies (mAb) (Fig. 1b). rVSV-LCMVG displayed remarkable cytotoxic effects on diverse tumor cell lines, even at multiplicity of infection (MOI) levels below 0.01. Notably, it exhibited particularly strong killing effects on liver and lung cancer cell lines, highlighting its potential as an oncolytic virus (Fig. 1c and Supplementary Fig. 1a). IC50 of rVSV-LCMVG for various cancer cell lines was in Supplementary Fig. 1b. To evaluate its efficiency in infecting and producing LCMVG in tumor cells, we infected B16-OVA cells with rVSV-LCMVG at different multiplicities of infection (MOI), 16h later the expression of VSV-P and LCMVG could be detected (Supplementary Fig. 1c, d). We also conducted an assessment of the proportion of tumor cells that exhibited positivity towards LCMVG and VSV-P antigens following exposure to different rVSV-LCMVG MOIs for 12, 24, and 48h. Flow cytometry analysis demonstrated a significant increase in the proportion of tumor cells expressing LCMVG and VSV-P, which was dependent on the MOI (Supplementary Fig. 1e). Compared to the wild-type VSV, the rVSV-LCMVG also exhibited significantly enhanced safety. The intracranial injection of 1102 plaque-forming units (PFU) of the wild-type VSV led to the mortality of all mice, whereas all mice that received 1106 PFU of rVSV-LCMVG survived (Fig. 1d and Supplementary Fig. 1f). Compared to the wild-type VSV, the modified rVSV-LCMVG demonstrated a low propensity to induce the production of neutralizing antibodies after multiple intravenous doses (Fig. 1e). C57BL/6J mice were intravenously injected with rVSV-LCMVG at 1107 PFU and no significant weight loss between day 1 to day 30 postinjection when compared with PBS-treated controls (Supplementary Fig. 2a, b). To provide a more detailed analysis of potential toxicity, the same doses of rVSV-LCMVG were injected intravenously and serum ALT (Alanine aminotransferase) well as AST (Aspartate aminotransferase) were determined. Both levels were not elevated in any of the group throughout the observation period, indicating a lack of potential toxicity (Supplementary Fig. 2c, d). Quantitative RT-PCR showed that the rVSV-LCMVG virus genome decreased gradually with the extension of infection time in the blood, heart, liver, spleen, lung, kidney and brain of the treated animals (Supplementary Fig. 2e). These results suggested that rVSV-LCMVG exhibited safety as an oncolytic virus in the treatment of tumors, and it could be employed in a multi-injection, multi-course administration strategy to mitigate the influence of neutralizing antibodies.
Characterization of rVSV-LCMVG, which could effectively deliver GP33 to tumor cells to direct the activation and cytotoxicity of P14-TCR-T cells in vitro. a Schematic of oncolytic virus rVSV-LCMVG showing the G gene of VSV genome replaced by the G gene of LCMV. b Electron micrographs of VSV and rVSV-LCMVG, and identification of N, P, M, LCMVG protein expression via western blot analysis. c Murine and human cancer cells were infected with rVSV-LCMVG at the indicated MOIs. Cell viability was analyzed at 48h after virus infection, using CCK8 cell viability assay kits. d Inoculation with wild-type virus VSV or rVSV-LCMVG via intracranial injection, to monitor the survival of mice. e Inoculation 1107 PFU of rVSV-LCMVG or VSV by intravenous injection, one dose every three days and every three injections is a course of treatment, the blood is collected to detect the content of neutralizing antibodies in serum. f Results of B16-OVA tumor cell killing assay, as visualized by phase-contrast microscopy. Representative images are shown. Scale bar, 50m. g Expression of cell surface CD69, ICOS, and CD107a on P14 cells after 16-hour coculture with B16-OVA tumor cells in the presence or absence of the indicated MOI of rVSV-LCMVG. h IFN- production in supernatants measured by enzyme-linked immunosorbent assay (ELISA) collected from cocultures with P14 at indicated MOIs for 16h
To assess the susceptibility of rVSV-LCMVG-infected cells to specific T-cell-mediated killing, B16-OVA cells were infected with rVSV-LCMVG for 16h and co-cultured with P14 cells, which can recognize LCMV-GP33, at effector: target (E:T) ratios of 1:1. The group that underwent combined rVSV-LCMVG infection and P14 cells coculture exhibited significantly higher levels of killing compared to B16-OVA cells infected with rVSV-LCMVG alone or co-cultured with P14 cells alone at each time point (Fig. 1f). CD69 and ICOS were employed as T-cell activation surface markers, while CD107a levels on the cell surface and the concentration of interferon- (IFN-) in the supernatant were used to assess P14 cells function. The activity of P14 T cells, which were co-cultured for 16h with rVSV-LCMVG infected B16-OVA cells, exhibited robustness that was dependent on the rVSV-LCMVG MOI (Fig. 1g, h). These findings suggest that OVs have the capability to deliver antigens, in this case LCMVG to tumors and enhance antigen-specific T-cell-mediated antitumor responses.
Given the limitations of OVs and adoptively transferred T-cell monotherapy for the treatment of solid tumors, we conducted a study to investigate the potential of combination therapy. In this study, we utilized the B16-GP33 melanoma model, which expresses the exogenous antigen GP33, to assess the effectiveness of combination therapy involving rVSV-LCMVG and P14 cells. Once the tumor size reached approximately 100mm3 following the subcutaneous injection of B16-GP33 cells, we transferred P14 cells (2106 cells per mouse) on day 0, relative to treatment. The next day, on day 1, the tumors were intratumorally (i.t.) injected with rVSV-LCMVG 1107 PFU per dose for every 3 days for 12 consecutive days (Fig. 2a). To investigate the impact of each component of combinatorial treatment on B16-GP33 tumor growth, groups of mice with established tumors were assigned to four treatment groups: PBS (control), rVSV-LCMVG alone, P14 alone, or combination therapy with rVSV-LCMVG and P14. Tumor growth was assessed every three days. As expected, mice treated with either P14 cells alone or rVSV-LCMVG alone exhibited slower tumor growth compared to the control group treated with PBS. Combination therapy resulted in significant tumor regression and a substantial increase in survival time. 10 days after the injection of rVSV-LCMVG, mice treated with either P14 T cells or rVSV-LCMVG alone showed a moderate reduction in tumor volume, whereas the P14 combined with rVSV-LCMVG group completely eliminated the tumor after 19 days. Furthermore those receiving dual treatment survived for more than 35 days until the conclusion of the experiment (Fig. 2b and Supplementary Fig. 3a). Therefore, in an attempt to address the limited therapeutic impact of systemically administering OVs, we sought to enhance the therapeutic efficacy by combining rVSV-LCMVG with P14 through intravenous injection at an equivalent dosage to the previous intratumoral injection. We transferred P14 into B16-GP33-bearing mice one day before the administration of rVSV-LCMVG (Fig. 2c). Tumors that progressed in the group receiving intravenous administration of rVSV-LCMVG maintained similar levels compared with those in the group receiving PBS treatment. However, when P14 was combined with intravenous administration of rVSV-LCMVG, there was a significant improvement in tumor treatment efficacy and survival rates. (Fig. 2d and Supplementary Fig. 3b).
Antitumor efficacy of rVSV-LCMVG combined with P14 cells in B16-GP33 tumor models. a Schematic of B16-GP33 tumor-bearing mice treated with rVSV-LCMVG and P14 T cells. b Tumor volumes are shown as mean values with SEM (n=5 per group). Survival curves of C57BL/6J mice from the experiment described in a are shown. *p<0.05; **p<0.01; ***p<0.001; ****p<0.0001, based on two-way ANOVA with post hoc HolmSidak test; survival analysis was conducted using log rank test. c Schematic of the treatment was the same as that in (a), except oncolytic virus was administered intravenously. d Tumor volumes are shown as mean values with SEM (n=5 per group). Survival curves of C57BL/6J mice from the experiment described in c are shown. e Representative flow cytometric analysis showing abundance of inhibitory receptors (PD-1 and LAG3) and activation molecules ICOS on tumor-infiltrating P14 cells isolated from the tumor. f Quantification (geometric mean of fluorescence intensity) of the expression levels of PD-1, LAG3 and ICOS on tumor-infiltrating P14 cells. Each dot represents one mouse. g Flow cytometry plot showing the fraction of P14 (CD90.1+) cells in the total CD8+ T-cell gate from the tumor, draining lymph node, and spleen of a representative mouse. h Quantification of P14 in g. Each dot represents one mouse. i Representative intracellular staining for the cytokines IFN- and GZMB. j Summary of cytokine production by P14 cells. Each dot represents one mouse. Horizontal bars show the minimum and maximum values (*p<0.05, **p<0.01, ***p<0.001, ****p<0.0001, ns means not significant based on the Mann Whitney test)
To investigate the mechanisms by which rVSV-LCMVG enhances the effects of adoptive T-cell therapy, we examined the number, phenotype, and function of P14 cells in tumors and the peripheral region using flow cytometry. This analysis was performed after intratumoral administration of two doses of the oncolytic virus on the fifth day. We observed changes in the functions of P14 cells in the P14 transferred group. These cells upregulated inhibitory receptors, such as PD-1 and LAG3, downregulated the expression of the co-stimulatory molecule ICOS. Furthermore, P14 cells in the P14 combined with rVSV-LCMVG group showed reduced expression levels of LAG3 and PD-1, as well as increased expression levels of ICOS (Fig. 2e, f). Additionally, P14 cells obtained from the tumors, including draining lymph nodes and spleen, showed higher abundance in the group treated with a combination of P14 cells and rVSV-LCMVG, compared to the group treated with P14 cells alone. (Fig. 2g, h). P14 cells in the P14 transferred group also exhibited lower levels of IFN- and GZMB upon ex vivo restimulation. P14 cells in the P14 combined with rVSV-LCMVG group produced more IFN- and GZMB upon restimulation ex vivo, compared with P14 transferred group (Fig. 2i, j), indicating improved P14 cells function in the TME. Consistent with the rapid development of P14 cells dysfunction, the aggressive growth of the B16-GP33 melanoma tumor could only be controlled by the adoptive transfer of P14 cells during the early stages of the disease. We also analyzed the expression of 36 soluble cytokines and chemokines in the B16-GP33 tumor using the Luminex beads method, in addition to detecting specific T cells cytokine production. In tumors treated with the combination therapy of rVSV-LCMVG and P14 cells, the intratumor levels of IFN-, TNF-, IL-2, IL-12, IL-15, and GM-CSF were significantly higher compared to the single-strategy group. These elevated levels of cytokines could induce tumor regression and stimulate systemic immunity. Furthermore, treatment with the combination therapy also led to significantly higher levels of CCL5 and CXCL10, which may attract inflammatory cells to the injection site (Supplementary Fig. 3c). Therefore, the continuous injections of rVSV-LCMVG after infiltration of P14 cells into the tumor altered the cytokine profile in the TME, as the infiltrating cells responded to rVSV-LCMVG treatment. Correspondingly, the combination of P14 and rVSV-LCMVG treatment significantly enhanced the survival rates of mice bearing B16-GP33 tumors. These findings suggest that the improved tumor control observed after the combination therapy was mediated by the oncolytic virus, which promotes greater infiltration of T cells and enhances their antitumor capacity within the reconstituted tumor immune microenvironment. Consequently, the combination therapy with oncolytic virus has a profound impact on the responses to adoptively transferred T-cell therapy.
To further investigate the changes of tumor-specific and virus-specific T cells when combined oncolytic virus therapy, the antitumor activity of this combination approach was tested in a syngeneic tumor model using C57BL/6J mice bearing subcutaneous B16-OVA tumors, a melanoma cell line engineered to express the exogenous antigen chicken ovalbumin (OVA). The melanoma cell line B16-OVA was subcutaneously injected firstly, and when the tumor size reached approximately 100mm3, an appropriate amount of P14 and OT-I (2106 cells per mouse) were transferred on day 0 (relative to treatment). On the next day, followed by four doses of oncolytic virus therapy, one dose every three days, rVSV-LCMVG 1107 PFU/dose (Fig. 3a). A modest decrease in tumor burden and an enhancement in overall survival were observed in mice with intratumoral injection of four doses of 1107 PFU rVSV-LCMVG. Furthermore, significant tumor suppression was observed in the group receiving combined treatment, leading to a more effective extension of the survival rates of mice. (Fig. 3b and Supplementary Fig. 4a). In addition to intratumoral administration, we also assessed the therapeutic efficacy of intravenous administration of the oncolytic virus in conjunction with T cells in the B16-OVA tumor model (Fig. 3c). Compared to the single treatment group, the co-administration of T cells along with intravenous administration of oncolytic virus demonstrated a notable therapeutic effect in inhibiting tumor growth and extending the lifespan of mice (Fig. 3d and Supplementary Fig. 4b). Tumor-specific OT-I T cells isolated from the tumors exhibited high levels of PD-1 and LAG3, whereas bystander P14 cells isolated from the same tumors displayed much lower levels of these markers. Furthermore, the expression of PD-1 and LAG3 decreased in OT-I cells when combined with rVSV-LCMVG treatment, while the expression of ICOS increased (Fig. 3e, f). Furthermore, 5 days after transfer, both OT-I and P14 cells infiltrated the tumors in the OT-I&P14 treatment group, with OT-I cells showing higher levels of infiltration compared to non-specific P14 cells in B16-OVA tumors, while enhanced recruitment of virus-specific P14 T cells was observed in the presence of rVSV-LCMVG. Additionally, tumors, draining lymph nodes, and spleen exhibited a similar trend (Fig. 3g, h and Supplementary Fig. 4c). In addition, OT-I tumor-infiltrating lymphocytes (TILs) demonstrated decreased production of IFN- compared to OT-I cells in the spleen. However, when mice were treated with a combination of OT-I and P14 cells along with rVSV-LCMVG, the levels of cytokines secreted by both cells significantly increased in tumors, draining lymph nodes, and spleens (Fig. 3i, j and Supplementary Fig. 4d). The findings demonstrate that the tumor-specific T cells infiltrating the tumor site show signs of exhaustion. Nevertheless, when administered in combination with the oncolytic virus rVSV-LCMVG therapy, the exhaustion phenotype of the tumor antigen-specific T cells (OT-I) can be reversed. Additionally, the detection of cytokines revealed an augmented secretion by the combined OT-I cells and oncolytic virus, thereby intensifying the antitumor effect.
Antitumor efficacy of combination therapy of rVSV-LCMVG and P14, OT-I cells in B16-OVA tumor models. a Schematic of B16-OVA tumor-bearing mice treated with rVSV-LCMVG and OT-I and P14 T cells. b Tumor volumes are shown as mean values with SEM (n=5 per group). Survival curves of C57BL/6J mice in a are shown. *p<0.05; **p<0.01; ***p<0.001; ****p<0.0001, based on two-way ANOVA with post hoc HolmSidak test; survival analysis was conducted by log rank test. c Schematic of the treatment was the same with a, except oncolytic virus was administered intravenously. d Tumor volumes are shown as mean values with SEM (n=5 per group). Survival curves of C57BL/6J mice from the experiment are described in c. e Representative flow cytometric analysis showing abundance of inhibitory receptors (PD-1 and LAG3) and activation molecules ICOS on tumor-infiltrating OT-I and P14 cells isolated from the tumor. f Quantification (geometric mean of fluorescence intensity) of the expression levels of PD-1, LAG3, and ICOS in tumor-infiltrating OT-I and P14 cells. Each dot represents one mouse. g Flow cytometry plot showing the fraction of OT-I (CD45.1+) cells in the total CD8+ T-cell gate, in the tumor, draining lymph node, or spleen of a representative mouse. h Quantification of the OT-I and P14 in the total CD8+ T-cell gate, in the tumor, draining lymph node, or spleen. Each dot represents one mouse. i Representative intracellular staining for the cytokines IFN- and GZMB. j Summary of cytokine production by OT-I and P14 cells upon restimulation with cognate peptides. Each dot represents one mouse. Horizontal bars show the minimum and maximum values (*p<0.05, **p<0.01, ***p<0.001, ****p<0.0001, ns means not significant based on the Mann Whitney test)
Next, multiplex immunofluorescence imaging was performed to better characterize structures within the tumor and draining lymph nodes at the cell-cell interaction level. When examining the draining lymph nodes, it was observed that the ratio of OT-I and P14 T cells in the combined treatment group was significantly higher compared to the single treatment group (Supplementary Fig. 5a, b). In the tumor region, there was a notable increase in the overall infiltration of CD8 T cells, OT-I, and P14 T cells in tumors treated with T cells in conjunction with rVSV-LCMVG, as opposed to the adoptive transfer of OT-I and P14 alone. Moreover, we found a close colocalization of PD-1 and CD8 expression in tumors, with a relatively low expression level of PD-1 in the combined treatment group (Supplementary Fig. 5c, d). This finding was consistent with previous flow cytometry results.
The aforementioned studies demonstrated distinct proliferative and differentiation responses of tumor-specific T-cell OT-I and virus-specific T-cell P14 to various treatments. Thus, it became crucial to explore the disparities in the transcriptional signatures of these T cells expanded after adoptive transfer of T-cell monotherapy or combined oncolytic virus therapy. To accomplish this, RNA sequencing (RNA-seq) analysis was conducted on the sorted tumor-specific and virus-specific T cells obtained from mice in both treatment groups with B16-OVA tumors. The RNA-seq results indicated significant alterations in the gene expression profiles of both tumor-specific and virus-specific T cells in mice treated with combination therapy as opposed to those treated with monotherapies (Fig. 4a, b and Supplementary Fig. 5e).
OT-I and P14 T cells have distinct transcriptional profile when combined with rVSV-LCMVG in B16-OVA. Transcriptome kinetics of OT-I and P14 T cells following a transfer of OT-I and P14 T cells into B16-OVA tumor-bearing mice on day 0, then followed by two doses of rVSV-LCMVG intratumorally administered on day 1 and day 4 (or not). For bulk RNA-seq, OT-I and P14 T cells were harvested and sorted on day 5. a Principal components analysis of mRNA matrix from all cells in combination treatment group or the monotherapy. b Venn-diagram showing differential RNA-seq peaks for OT-I and P14 T cells in combination treatment group compared to the monotherapy. c Differences in pathway activity scores of OT-I T cells between the combination treatment and monotherapy groups. d Differences in pathway activity scores of P14 T cells between the combination treatment and monotherapy groups. e Volcano plot of differentially expressed genes fold changes in OT-I T cells between the combination treatment and monotherapy groups. f Heatmap depicting representative protein export genes of OT-I T cells from the combination treatment and monotherapy groups. g Volcano plot of differentially expressed genes fold changes in P14 T cells between the combination treatment and monotherapy groups. h Heatmap depicting representative protein export genes of P14 T cells from the combination treatment and monotherapy groups
Pathway enrichment by gene set variation analysis was performed at the same time as the previous flow analysis on day 5 after adoptive transferred. In the oncolytic virus combined with adoptive T-cell therapy group, both OT-I and P14 cells showed enrichment for cytokine activity, the granzyme-mediated cell death pathway, and positive regulation of T-cell proliferation. Notably, combination treatment resulted in pathway enrichment in granzyme-mediated cell death in P14 CD8+ T cells. (Fig. 4c, d). The expression of various inhibitory receptors and transcription factors, such as Tox, Slamf6, Egr2, and Eomes, known to be associated with T-cell exhaustion, was found to be downregulated in OT-I cells from mice that received combination therapy of rVSV-LCMVG and T cells, compared to the cells isolated from the monotherapy group. In contrast, there was an upregulation in the expression of genes encoding effector molecules and inflammatory cytokine receptors, including Gzmb, Gzmk, Gzma, Ccr5, Ifng, and Stat1, in mice receiving the combination therapy. (Fig. 4e, f). Furthermore, the combined therapy not only reversed the exhausted phenotype of tumor antigen-specific T cells OT-I but also amplified the antitumor effects by enhancing the production of cytokines by virus-specific T cells (Fig. 4g, h). The study findings indicated that both OT-I and P14 T cells treated with the combination therapy exhibited a reduction in exhaustion signature, while demonstrating an increase in effector signatures.
To gain a deeper understanding of how the differentiation process of tumor-specific and virus-specific T cells was affected by rVSV-LCMVG, we conducted single-cell RNA sequencing (scRNA-seq) analysis on these T cells following various in vivo treatments. We focused specifically on tumor-specific OT-I T cells obtained from B16-OVA engrafted C57BL/6J mice. These T cells were then categorized into ten major clusters based on their characteristics: early activated T cells, Xcl1+ T cells, Il7r+ Tem cells, Nme1+ T cells, ISG+ Teff cells, Tcf7+ Tex cells, Gzmb+ Teff cells, S phase Tex cells, Temra cells, and G2m phase Tex cells. (Fig. 5a). OT-I T cells without rVSV-LCMVG stimulation were primarily found in exhausted T-cell clusters (G2m phase Tex, S phase Tex, and Tcf7+ Tex). However, when the TME was remodeled by rVSV-LCMVG, OT-I T cells predominantly belonged to effector T-cell clusters, including early activated T cells, ISG+ Teff cells, Temra cells, and Il7r+ Tem cells (Fig. 5b). In addition, OT-I cells exhibited elevated expression of Runx3 following treatment with combined OVs. This indicates that these OT-I cells may persist in tumor tissues for an extended duration, thereby exerting antitumor effects (Fig. 5c). Consistent with our previous findings, the administration of rVSV-LCMVG ameliorated the exhaustion phenotype of tumor-specific T cells by promoting the differentiation of Tex into effector T cells.
Transcriptional profiling of OT-I tumor-specific CD8+ T cells using scRNA-seq. a Uniform manifold approximation and projection (UMAP) visualization of the scRNA-seq clusters of OT-I tumor-specific CD8+ T cells from 6 samples in different groups. b Bar plot demonstrating percentages of cells in clusters as a fraction of total cells for each sample, related to the UMAP plot in a. c Dot plot representing the relative average expression of a subset of marker genes of OT-I tumor-specific CD8+ T cells in different groups. d Dot plot representing the relative average expression of a subset of marker genes across all clusters. e Single-cell transcription levels of representative genes illustrated in the UMAP plot from a. Transcription levels are color coded: gray, not expressed; blue, expressed
Next, we further validated the differentially expressed gene patterns of clusters that were significantly perturbed by rVSV-LCMVG treatment. G2M phase Tex expressed canonical exhaustion-related genes (Pdcd1, Ung, Mcm2, Ccnb2, and Top2a). Tcf7+ Tex was identified as the proliferative progenitor of terminally exhausted T cells. Nme1+ T cells expressing Nme1, Ccr7 and Npm1, were highly connected to Tcf7+ Tex cells. ISG+ effector T cells were further categorized based on Stat1, Isg15, Ifit3, and Gzmb expression. Il7r+ Tem highly expresses the signature of memory T cells (Il7r, Zfp36l2, Gpr183, Cxcr4, and Sell). Taken together, rVSV-LCMVG administration promotes tumor-specific exhausted (Tex) differentiation into effector (Teff) and memory (Tmem) cells with a significant decline in Tex proportion (Fig. 5d, e).
When analyzing virus-specific T cells, we observed that all samples could be classified into 13 distinct clusters. These clusters include early activated T cells, G2m phase Tex cells, Gzmb+ Teff cells, Il7r+ Tem cells, ISG+ Teff cells, ISG+ Bystander cells, Nave-like T cells, Nme1+ T cells, S phase Tex cells, Regulator-like CD8 cells, Tcf7+ Tex cells, Xcl1+ T cells, and Terminally Tem cells. (Supplementary Fig. 6a, b). Combined with OVs, P14 virus-specific T cells differentiate from naive T cells into Teff and Tmem cells. In contrast, tumor-specific T cells undergo differentiation from Tex to Teff and Tmem cells (Supplementary Fig. 6c). This indicated that the adoptive transfer of tumor-specific T cells alone resulted in their differentiation into exhausted and disabled T cells upon tumor infiltration. However, when tumor-specific T cells were used in combination with the oncolytic virus rVSV-LCMVG, they effectively reversed exhaustion and improved their antitumor ability.
Given the high cost and challenges associated with personalized CAR T or TCR-T treatment, the induction of specific T cells through mRNA vaccines holds the potential to establish a more transformative therapeutic strategy. In this study, we explored the possibility of indirectly inducing tumor-specific T cells to replace the direct reinfusion of T cells. Instead of transferring P14 cells, we employed LCMV-Armstrong virus to induce specific T cells that recognize the gp33 epitope. Subsequently, we detected a certain proportion of these specific T cells in the peripheral blood, spleen, and lymph nodes of the abdominal groove. (Supplementary Fig. 7a, b). In the B16-GP33 model, we utilized LCMV-Armstrong immune-induced specific T cells along with the rVSV-LCMVG oncolytic virus, this combined approach demonstrated a notable efficacy in inhibiting tumor growth. It is important to highlight that the treatment effect was significantly superior to that of using the oncolytic virus alone. Furthermore, the combination therapy also led to a noticeable extension in the survival rate of mice as compared to the monotherapy treatment involving immune LCMV-Armstrong. (Supplementary Fig. 7ce). In the B16-GP33 tumor model, immune LCMV-Armstrong effectively generated GP33-specific T cells, which successfully suppressed tumor growth. Then, we applied the same treatment strategies in the B16-OVA model to validate the results. The findings demonstrated that GP33-specific T cells induced by LCMV-Armstrong, which solely targeted the antigens carried by rVSV-LCMVG OVs and did not recognize tumor-associated antigens, when combined with rVSV-LCMVG could effectively restrain the growth of B16-OVA tumors and significantly prolonged the survival of mice. (Supplementary Fig. 7fh). These results suggested that in addition to tumor-specific T cells, in the combination therapy using virus-specific T cells could also achieve better therapeutic effects.
Next, we prepared the mRNA tumor vaccine which could express gp33 epitope and we verified the expression of gp33 at the cellular level by immunofluorescence using an earlier G2B1 antibody that specifically recognizes the gp33 epitope (Supplementary Fig. 8a). Mice were immunized intramuscularly with a dose of 10g per mouse. The specific T cells capable of recognizing the gp33 epitope were identified seven days after immunization. After an interval of 14 days since the initial dose, the same vaccine dose was administered to enhance the immune response. Subsequently, after five days, an increase in the number of specific T cells in the spleen was observed (Fig. 6a, b). IFN- enzyme-linked immunosorbent spot (ELISpot) test results showed T cells from the immunized mice spleen had a strong response when stimulation with gp33-41 antigenic peptides ex vivo (Fig. 6c, d).
mRNA tumor vaccine combined with oncolytic virus improved the therapeutic effect. a Representative flow cytometry plot showing the fraction of gp33-specific T cells in the total CD8+ T cells gate from the spleen. b Quantification of the gp33-specific T cells. The proportion of cells in CD8 (left) and the total cell number (right). Each dot represents one mouse. c Representative well images of the IFN- ELISpot response of the gp33-specific T cells isolated from spleen in different groups. d Numbers of IFN- SFCs (spot-forming cells) of the gp33-specific T cells isolated from spleen were quantified after stimulation with GP33-41 peptide. e Schematic of B16-GP33 or B16-OVA tumor-bearing mice treated with gp33-mRNA and rVSV-LCMVG. f B16-GP33 tumor volumes are shown as mean values with SEM. Tumor response data derived from mice (n=5) are shown. *p<0.05; **p<0.01; ***p<0.001; ****p<0.0001, based on two-way ANOVA with post hoc HolmSidak test. g Survival curves of C57BL/6J mice from the experiment described in f are shown; survival analysis was conducted by log rank test. h B16-OVA tumor volumes are shown as mean values with SEM, (n=5). *p<0.05; **p<0.01; ***p<0.001; ****p<0.0001, based on two-way ANOVA with post hoc HolmSidak test. i Survival curves of C57BL/6J mice from the experiment described in h are shown; survival analysis was conducted by log rank test
To determine the efficacy of mRNA vaccines combined with OVs in eliminating established tumors in vivo, we administered subcutaneous injections of 2106 B16-GP33 cells per mouse. Once tumor formation was evident at the injection site, muscular immunization was conducted, with each mouse receiving a dose of 10g mRNA. Following a 7-day interval, oncolytic virus therapy was administered (Fig. 6e). The intratumoral injection of rVSV-LCMVG or mRNA vaccine monotherapy resulted in a moderate inhibition of tumor growth compared to the PBS group. Combination therapy with intratumoral or intravenous injection of rVSV-LCMVG in combination with mRNA vaccines largely improved the responsiveness of B16-GP33 tumors and prolonged the survival of these mice (Fig. 6f, g and Supplementary Fig. 8b). In combination therapy using mRNA vaccines, the therapeutic efficacy of the rVSV-LCMVG oncolytic virus was found to be superior in the intravenous injection group compared to the intratumoral administration. This may be attributed to the fact that, after immunization with mRNA vaccines, the intravenous administration of OVs stimulated a stronger systemic immune response than the intratumoral administration. As a result, there was an increase in the production of specific T cells and improved therapeutic outcomes. Even in the B16-OVA model, mRNA was only able to induce the generation of virus-specific T cells, also emphasizing that the combination therapy approach yielded better therapeutic results (Fig. 6h, i and Supplementary Fig. 8c). Our results highlight that while using mRNA to induce oncolytic virus-specific T cells or tumor-specific T cells, combined therapy with oncolytic virus would lead to a better therapeutic effect, especially when the mRNA-induced specific T cells could recognize both tumor and OVs, even if the oncolytic virus was administered intravenously, mice would gain a better therapeutic effect compared to monotherapy.
A landmark study by scientists at the University of Oxford, has unveiled crucial insights into the way that COVID-19 vaccines mitigate severe illness in those who have been vaccinated.
Despite the global success of COVID-19 vaccination campaigns, concerns remain around the continued spread of this disease including in vaccinated individuals. For this reason, researchers at the Oxford Vaccine Group conducted an extensive investigation into the human immune response to COVID-19, in both vaccinated and unvaccinated individuals.
Employing contemporary 'big-data' analyses, scientists can find novel associations between fundamental biological entities and indicators of the severity of a disease to build patterns of health and disease. Results of this study categorically show a reduction in indicators of disease severity in those who had received the vaccine, demonstrating that the harmful inflammatory reaction to COVID-19 is less severe in those who have been vaccinated, when compared with those who havent.
Professor Daniel O'Connor, Head of Bioinformatics at the Oxford Vaccine Group (OVG), led the study. He said: 'These results confirm the efficacy of vaccination and its pivotal role in reducing the harmful consequences associated with COVID-19. The results of our research highlight the ChAdOx1 nCoV-19 vaccine's ability to modulate harmful responses to the SARS-CoV-2 virus, and therefore to reduce the severity of illness. The implications of these findings are far-reaching, offering evidence that is fundamental to future vaccine development and pandemic mitigation strategies. It also provides valuable guidance for policymakers and public health experts.'
Professor Sir Andrew Pollard, Ashall Professor of Infection and Immunity and Director of the Oxford Vaccine Group, said: 'Better understanding of how vaccines can reduce the severity of infections caused by viruses like COVID-19 is a key part of our preparedness to make effective vaccines against the next pandemic threat. Ongoing research is critical as we know the next one is coming but we dont know which virus or when it will be.'
The study employed state-of-the-art technologies, including RNA-sequencing (to capture the level of genes produced by blood cells), to achieve these results. While the findings are promising, the study acknowledges limitations such as a focus on mild cases and sample size constraints, highlighting the need for further research utilising advanced techniques to enhance resolution.
Key findings from the study include:
Funding for the study was provided by various organisations, including the National Institute for Health Research (NIHR), Oxford Biomedical Research Centre, and Oxford Nanopore Technologies. Notably, the ChAdOx1 nCoV-19 randomised controlled trials received support from UK Research and Innovation, NIHR, Coalition for Epidemic Preparedness Innovations, Bill & Melinda Gates Foundation, among others.
Link to the research paper in Nature Communications: Multi-omics analysis reveals COVID-19 vaccine induced attenuation of inflammatory responses during breakthrough disease
