Rare Reactions Might Hold Key to Variant- Proof Covid

News in focus job of blocking pseudoviruses with B.1.351 mutations. To Moore’s surprise, the antibodies also blocked other strains, including a variant called P.1, identified in Brazil, that shares several mutations with B.1.351. Sigal’s team reported similar results in February3. Moore does not know why B.1.351 infection results in a such a broad immune response, but she is working to find out. “It’s about the only thing I think about these days,” she says. It’s possible that the antibodies are recognizing features of the viral spike protein that do not differ between those variants. The results are a boost to nascent efforts to develop vaccines that can cope with variants such as B.1.351. In mid-March, updated versions of Moderna’s vaccine, based on the genetic sequence of the B.1.351 variant, were given to trial participants for the first time. Other devel- DESIGN CELLS/SPL An illustration of the spike proteins that SARS-CoV-2 uses to break into human cells. opers, including Pfizer–BioNTech, also plan to test vaccines based on B.1.351. Different coronavirus variants can trigger different immune responses, and researchers are RARE REACTIONS MIGHT only beginning to map their full diversity. Infec- tion with a fast-spreading variant identified in HOLD KEY TO VARIANT- the United Kingdom, known as B.1.1.7, seems to provoke antibodies that do a poor job against PROOF COVID VACCINES B.1.351 and earlier variants6, according to work led by immunologist George Kassiotis at the Some people mount an immune response that can Francis Crick Institute in London and virologist Eleni Nastouli at University College London. fend off a menagerie of SARS-CoV-2 variants. Again, it’s not clear why B.1.1.7 seems to gen- erate a narrow immune response. The variant By Ewen Callaway South Africa’s first wave, earlier in the year, is handled by existing vaccines — which are and because it carried changes that blunted based on the virus that emerged in Wuhan, enny Moore was one of the first the potency of some antibodies that ordinarily China, in late 2019 — but researchers urgently scientists to show that a coronavirus disable SARS-CoV-2. need to determine whether vaccines based on variant identified in South Africa Research led by Moore and Alex Sigal at the B.1.351 can also cope with B.1.1.7, says Kassiotis. could dodge the immune system. So Africa Health Research Institute in Durban If not, future vaccines might need to immunize the virologist was expecting more stoked early worries over B.1.351 in January2,3. simultaneously against multiple variants, in a Pgrim news when she tested the responses It showed that the variant evaded virus-block- similar way to seasonal influenza jabs. of people who had been infected with that ing antibodies produced by a large number of variant, named B.1.351. people who had been infected with first-wave Vaccine resilience Instead, her team found a ray of hope: B.1.351 strains. Weeks later, clinical-trial results showed Redesigning vaccines is not necessarily the infection triggered antibodies that fended off that the variant diminished the efficacy of vac- only way to cope with emerging coronavirus variants old and new. “That was a surprise,” cines developed by Novavax4 and Johnson & variants. Researchers are identifying other says Moore, who is based at the National Insti- Johnson, and potentially wiped out much of factors that could make existing vaccines tute for Communicable Diseases and the Uni- the protection conferred by AstraZeneca’s jab5. more resilient, such as mimicking how natu- versity of the Witwatersrand in Johannesburg. ral immunity caused by infection can some- The discovery, posted on bioRxiv last month1, ‘Pseudovirus’ surprise times offer broad protection. For instance, joins a slew of recent research suggesting that Moore hoped that B.1.351 infection would Bieniasz’s team found that some people who vaccines for COVID-19 might cope with existing trigger strong immune responses, but she recover from COVID-19 make antibodies that, variants — and maybe even future ones. was open to the possibility that this variant over time, become more capable of blocking “Getting vaccines that will tackle the variants might be less visible to the immune system diverse coronavirus variants7. that are currently circulating is an eminently than are other strains. To find out, her team Antibody-producing B cells can evolve solvable problem,” says Paul Bieniasz, a virol- analysed antibodies from 89 people who had through natural selection to make antibodies ogist at the Rockefeller University in New York been hospitalized with B.1.351 infections. The that bind more tightly to their target, a process City, whose laboratory is studying variants. “It researchers used a ‘pseudovirus’ — a modified known as maturation. Bieniasz’s team isolated might be that we already have that solution.” form of HIV that infects cells using the SARS- B cells, at intervals of several months, from Researchers in South Africa identified B.1.351 CoV-2 spike protein — to measure the capacity people who had recovered from infection, in late 2020. It now accounts for the majority of the antibodies to block infection. and looked at how the potency of individual of the country’s cases and has spread around Reassuringly, people who recovered from antibodies changed as the B-cell lineages that the world. The variant attracted scientists’ B.1.351 infection made as many antibodies made them matured. attention because it was linked to outbreaks as did those infected with earlier circulat- In some instances, ‘matured’ antibodies in places that had already been hit hard by ing variants. Those antibodies did a good recognized variants, including B.1.351, that 20 | Nature | Vol 592 | 1 April 2021 ©2021 Spri nger Nature Li mited. All ri ghts reserved. ©2021 Spri nger Nature Li mited. All ri ghts reserved. earlier versions of these antibodies failed to recognize; one matured type even neutralized Q&A some other coronaviruses. It’s not obvious how to make vaccines trigger such antibodies. Maturation occurs when viral molecules called antigens, which We need a non-political are recognized by antibodies, persist in the body. “Really, the way to drive the process is to way to track viruses have the antigen be as persistent as possible,” says Bieniasz. Formulating vaccines with adju- Rick Bright put his career on the line way of suppressing and revising science- vants — foreign molecules that increase their last year, when he blew the whistle on based messages, and that got us where potency — might be one way to achieve this. how then-US president Donald Trump’s we are today with the pandemic in the Some of the existing vaccines might already administration was mishandling the United States. So, a non-governmental, be triggering variant-resilient immune coronavirus pandemic. Bright, who was non-political entity would have the ability responses. In another March preprint, a director of the US Biomedical Advanced to seal and protect those data, and to make long-running COVID-19 study in Seattle, Wash- Research and Development Authority — sure that the world has access to all the ington, reported that after receiving a single which is responsible for countermeasures same information at the same time. dose of an mRNA vaccine, participants who had against pandemics, bioterrorism and previously been infected with SARS-CoV-2 pro- other health emergencies — was abruptly Why didn’t more government researchers duced heaps of antibodies that can neutralize removed from the agency. Now, he is speak out about the Trump administration’s B.1.351, as well as an earlier circulating variant8. trying his hand at curbing outbreaks from political meddling? Leonidas Stamatatos, an immunologist at outside the government. On 8 March, the We need more protections in place for the Fred Hutchinson Cancer Research Center Rockefeller Foundation, a philanthropic government employees and scientists who (FHCRC) in Seattle who co-led the study, sus- organization based in New York City that speak out or come forward. It was a very pects that a single vaccine dose boosted the funds science, announced that Bright difficult administration to work under as levels of pre-existing antibodies that were would become the senior vice-president a scientist. My scientific colleagues in the capable of recognizing diverse variants. It’s of its pandemic-prevention activities. His government were afraid of losing their jobs, not clear how to mimic this response in people first move will be to spearhead a plan to but were also working really hard to do the who haven’t had COVID-19. One possibility is use genomic sequencing and analysis right thing and push for the best decisions that a lag of several months between infection to track the coronavirus SARS-CoV-2 in with the right data. and vaccination was responsible, and that its the United States. Nature spoke to Bright I could only take so much. When the effect could be replicated with another vaccine about this project, and protecting integrity administration clearly, in my opinion, dose, given six months or a year after the first in science. showed a disregard for the general two, says Andy McGuire, an FHCRC immunol- population in a subject area that I know a lot ogist who co-led the study. Will Rockefeller give scientists grants to about — pandemic response — and pushed By showing such a broad immune response to sequence SARS-CoV-2? an unproven drug [hydroxychloroquine] variants, the latest data make researchers cau- Sequencing is important, but it’s not our to the general public without close clinical tiously optimistic that vaccines will be able to only emphasis.

Load more