In a recently published paper, my colleagues and I have identified extrafollicular B cell signatures in cases of severe COVID-19 similar to those we saw in active lupus. We showed that early on in the response to infection, patients with severe disease undergo a rapid activation of this fast-track pathway for antibody production. These patients produce high levels of viral-specific antibodies, some which are capable of neutralizing the virus. However, in addition to those protective antibodies, some that we saw look suspiciously like the ones found in autoimmune disorders such lupus.
In the end, patients with these autoimmune-like B cell responses fare poorly, with high incidences of systemic organ failure and death.
