Some Covid Survivors Have Antibodies That Attack the Body, not Virus


Some survivors of Covid-19 carry worrying signs that their immune system has turned on the body, reminiscent of potentially debilitating diseases like lupus and rheumatoid arthritis, a new study has found.

At some point, the body’s defense system in these patients shifted into attacking itself, rather than the virus, the study suggests. The patients are producing molecules called “autoantibodies” that target genetic material from human cells, instead of from the virus.

This misguided immune response may exacerbate severe Covid-19. It may also explain why so-called “long haulers” have lingering problems months after their initial illness has resolved and the virus is gone from their bodies.

The findings carry important implications for treatment: Using existing tests that can detect autoantibodies, doctors could identify patients who might benefit from treatments used for lupus and rheumatoid arthritis. There is no cure for these diseases, but some treatments decrease the frequency and severity of flare-ups.

Viral infections cause infected human cells to die. Sometimes the cells die a quiet death — but sometimes, and especially in the throes of severe infection, they can blow up, strewing their innards. When that happens, DNA, normally cloistered in coiled bundles inside the nucleus, is suddenly scattered and visible.

“It’s not just that these patients have an autoimmune-like immune response,” he said. “It’s that those immune responses are coupled with actual true testable clinical auto-reactivities.”

Some of the autoantibodies the researchers identified are associated with blood flow problems, noted Ann Marshak-Rothstein, an immunologist and lupus expert at the University of Massachusetts, Worcester.

“It’s very possible that some of the coagulation issues that you see in Covid-19 patients are being driven by these kinds of immune complexes,” she said.

If the autoantibodies do turn out to be long-lasting, she said, they may result in persistent, even lifelong, problems for Covid-19 survivors.

“You never really cure lupus — they have flares, and they get better and they have flares again,” she said. “And that may have something to do with autoantibody memory.”

Dr. Marshak-Rothstein, Dr. Iwasaki and dozens of other teams are closely studying the immune response to the coronavirus. Given the ease of testing for autoantibodies, it may soon become clear whether the antibodies were identified only because the researchers went looking for them, or whether they represent a more permanent alteration of the immune system.

“It’s not clear to me what it all means at this point,” Dr. Pepper said. “It’s going to take a little bit of time to understand if this is something that’s going to lead to downstream pathology.”


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