COVID-19 is associated with bystander polyclonal autoreactive B cell activation as reflected by a broad autoantibody production, but none is linked to disease severity.

Coronavirus disease 2019 (COVID-19) is associated with autoimmune features and autoantibody production in a small subset of the population. Pre-existing neutralizing antitype I interferons (IFNs) autoantibodies are related to the severity of COVID-19. Plasma levels of IgG and IgM against 12 viral antigens and 103 self-antigens were evaluated using an antibody protein array in patients with severe/critical or mild/moderate COVID-19 disease and uninfected controls. Patients exhibited increased IgGs against Severe acute respiratory syndrome coronavirus-2 proteins compared to controls, but no difference was observed in the two patient groups. 78% autoreactive IgGs and 93% autoreactive IgMs were increased in patients versus controls. There was no difference in the plasma levels of anti-type I IFN autoantibodies or neutralizing anti-type I IFN activity of plasma samples from the two patient groups. Increased anti-type I IFN IgGs were correlated with higher lymphocyte accounts, suggesting a role of nonpathogenic autoantibodies. Notably, among the 115 antibodies tested, only plasma levels of IgGs against human coronavirus (HCOV)-229E and HCOV-NL63 spike proteins were associated with mild disease outcome. COVID-19 was associated with a bystander polyclonal autoreactive B cell activation, but none of the autoantibody levels were linked to disease severity. Long-term humoral immunity against HCOV-22E and HCOV-NL63 spike protein was associated with mild disease outcome. Understanding the mechanism of life-threatening COVID-19 is critical to reducing mortality and morbidity.

COVID-19 mRNA vaccine BNT162b2 induces autoantibodies against type I interferons in a healthy woman.

Coronavirus disease (COVID-19) caused by SARS-CoV-2 virus is associated with a wide range of clinical manifestations, including autoimmune features and autoantibody production in a small subset of patients. Pre-exiting neutralizing autoantibodies against type I interferons (IFNs) are associated with COVID-19 disease severity. In this case report, plasma levels of IgG against type I interferons (IFNs) were increased specifically among the 103 autoantibodies tested following the second shot of COVID-19 vaccine BNT162b2 compared to pre-vaccination and further increased following the third shot of BNT162b2 in a healthy woman. Unlike COVID-19 mediated autoimmune responses, vaccination in this healthy woman did not induce autoantibodies against autoantigens associated with autoimmune diseases. Importantly, IFN-α-2a-induced STAT1 responses in human PBMCs in vitro were suppressed by adding plasma samples from the study subject post- but not pre-vaccination. After the second dose of vaccine, the study subject exhibited severe dermatitis for about six months and responded to treatments with Betamethasone Dipropionate Ointment and antihistamines for about one month. Immune responses to type I IFN can be double-edged swords in enhancing vaccine efficacy and immune responses to infectious diseases, as well as accelerating chronic disease pathogenesis (e.g., chronic viral infections and autoimmune diseases). This case highlights the BNT162b2-induced neutralizing anti-type I IFN autoantibody production, which may affect immune functions in a small subset of general population and patients with some chronic diseases.