“Next Generation” Vaccines May Be Needed to Work on New Covid Mutants: Scientists

The epidemic of Covid-19 variants is not an urgent issue, but scientists say it’s time for next-generation precautions to tackle them.

Vaccine research should continue in parallel. One is to tackle the SARS-CoV-2 virus with a first-generation vaccine, and the other is to prepare for possible mutations and new mutations. Experts say it depicts the future course of the infection.

Immunologist Satyajit Rath responded to concerns about the effectiveness of current vaccines in the face of new mutants, with the imminent problem of the absence or spread of vaccine-resistant viral variants at sufficient scale and rate. Said that it would be.

While current vaccination campaigns do help alleviate pandemics, “next-generation vaccines to address the most vaccine-resistant emerging variants have launched the first vaccination in the community. If so, it still needs to be developed, a scientist at the National Institute of Immunology in New Delhi told PTI.

An editorial in the journal Virulence earlier this week states that threats to vaccine efficacy come from both existing and future strains, including those reported by the United Kingdom, South Africa and Brazil.

The variants discovered so far have undergone changes or mutations that mean they can infect human cells more easily than the original version of the new coronavirus that initiated the pandemic.

Recent studies by researchers, including researchers at The Rockefeller University in the United States, regularly update the Covid-19 mRNA vaccine to avoid potential loss of clinical efficacy against newly emerging mutants. It suggests that it may be necessary.

This study, submitted to the preprint repository BioRxiv, has not yet been peer-reviewed or published in the journal.

The mRNA vaccine allows the body to provoke an immune response without getting sick, using synthetic RNA (genetic material) that encodes instructions for making certain proteins of the SARS-CoV-2 virus. To.

In some good news, studies suggest that mRNA vaccines with Moderna and Pfizer appear to work against some of the mutants tested.

A small study of moderna scientists found that the US pharmaceutical company’s COVID-19 vaccine was effective against new, more infectious variants of the pandemic virus found in the United Kingdom and South Africa. I found that I could see it.

Studies that have not yet been peer-reviewed suggest that vaccine-induced antibodies can recognize and fight new mutants.

Another study published last week suggests that the Pfizer vaccine provides protection against British variants.

According to experts, the current Covid-19 vaccine targets SARS-CoV-2 virus spelomers and is expected to cause the formation of antibodies that prevent the virus spelomers from adhering to human cells during infection. It has been.

The effectiveness of these vaccines is most likely to be affected by changes in the cell junctions of viral peplomer proteins.

According to immunologist Vineeta Bal, the effectiveness of current vaccines declines over time as the coronavirus continues to mutate.

“It is unlikely that a single new mutation in the virus that is currently prevalent is sufficient,” Baru of the Indian Institutes of Science Education in Pune told PTI.

Due to its persistence, the virus must maintain its ability for the receptor binding domain (RBD) of peplomers to bind intact to the ACE2 receptor.

Angiotensin converting enzyme 2, or ACE2 receptor, is a protein that provides a gateway for coronavirus to connect and infect a wide range of human cells.

RBD is an important part of the virus in its “spike” domain, docking with receptors in the body to invade cells and cause infection.

In the long run, Bal pointed out that vaccines can be less protective due to viral evolution.

“That’s expected and a concern. Monoclonal antibody therapy is more likely to be adversely affected than vaccines,” Baru said.

Monoclonal antibodies are laboratory-made proteins that mimic the ability of the immune system to fight off harmful antigens such as viruses.

“A monoclonal antibody binds to a very small portion of RBD, and mutations in that small portion can inhibit binding and thus the therapeutic utility of the monoclonal antibody.

“But vaccines can elicit many antibodies that cover most of the RBD surface together, compared to monoclonal antibodies,” she explained.

Currently, there are two variants with insightful datasets. One is the UK variant B.1.1.7 and the other is the South African variant B.1.351.

Florian Kramer, a professor of microbiology at Mount Sinai School of Medicine, said British variants may not have a significant impact on vaccine-induced immunity.

“B.1.1.7 does not appear to have a significant impact on vaccine-induced immunity. There may be monoclonal antibodies that can no longer bind / neutralize, but post-vaccinated sera seem to work.” He wrote in a tweet.

“But it is important that high antibody titers are induced, and not all vaccine candidates do it. The lower the initial titer, the greater the impact of these mutants, I I think that’s what you care about, “said scientists.

The antibody titer is the level of antibody in the blood determined by the test.

Rath commented on how long it would take to change the vaccine for future variants, and devised the next-generation vaccine variant as it took less than a year for the global community to devise multiple vaccines. He said it could be much easier and faster to do. To a new virus.

Bal said this could be relatively easier for some vaccines than others, such as viral mRNA-based vaccines.

“MRNA vaccines are probably the easiest to change, but other vaccines, such as adenovirus-based vaccines and protein subunit vaccines, can also be changed. The regulatory process for new approval of these vaccines needs to be developed. There is, “she added.

The new variant is a source of concern, but Rath said, “The real question is how much” extra “defense capacity the vaccine produces, and that” extra “amount rationalizes the” reduction “of efficiency. I wonder if it will be supplemented. It is this proof that we are looking for. ”

“The main question that has occurred and has not yet been asked is how well such a” mutant “vaccine works in individuals who are already immunized with one of the” original “vaccines. The pandemic isn’t over with us yet, “he added.

Developed by Hyderabad-based Bharat Biotech, Covaxin is effective against the UK version of COVID-19, according to a survey of 26 participants shared by the company on Wednesday.

India has recorded over 100 cases of British variants.