Coronavirus Deranges the Immune System in Complex and Deadly Ways | Kaiser Health News
▻https://khn.org/news/article/covid-autoimmune-virus-rogue-antibodies-cytokine-storm-severe-disease
In some people with severe covid, however, helper T cells don’t stand down when the infection is over, said James Heath, a professor and president of Seattle’s Institute for Systems Biology.
About 10% to 15% of hospitalized covid patients Heath studied had high levels of these cells even after clearing the infection. By comparison, Heath found lingering helper T cells in fewer than 5% of covid patients with less serious infections.
In affected patients, helper T cells were still looking for the enemy long after it had been eliminated. Heath is now studying whether these overzealous T cells might inflict damage that leads to chronic illness or symptoms of autoimmune disease.
“These T cells are still there months later and they’re aggressive,” Heath said. “They’re on the hunt.”
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New research shows that the coronavirus may activate preexisting autoantibodies, as well as prompt the body to make new ones.
In the January study**, half of the hospitalized covid patients had autoantibodies, compared with fewer than 15% of healthy people. While some of the autoantibodies were present before patients were infected with SARS-CoV-2, others developed over the course of the illness.
**▻https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7852238
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Dr. Shiv Pillai, a Harvard Medical School professor, notes that autoantibodies aren’t uncommon. Many healthy people walk around with dormant autoantibodies that never cause harm.
For reasons scientists don’t completely understand, viral infections appear able to tip the scales, triggering autoantibodies to attack, said Dr. Judith James, vice president of clinical affairs at the Oklahoma Medical Research Foundation and a co-author of Luning Prak’s study.