Factors associated with immune responses to SARS-CoV-2 vaccination in autoimmune disease individuals.

Patients with autoimmune diseases are at higher risk for severe infection due to their underlying disease and immunosuppressive treatments. In this real-world observational study of 463 autoimmune subjects, we examined risk factors for poor B and T cell responses to SARS-CoV-2 vaccination. We show a high frequency of inadequate anti-spike IgG responses to vaccination and boosting in the autoimmune population but minimal suppression of T cell responses. Low IgG responses in B cell-depleted multiple sclerosis (MS) subjects were associated with higher CD8 T cell responses. By contrast, subjects taking mycophenolate mofetil exhibited concordant suppression of B and T cell responses. Treatments with highest risk for low IgG anti-spike response included B cell depletion within the last year, fingolimod, and combination treatment with mycophenolate mofetil (MMF) and belimumab. Our data show that the mRNA-1273 (Moderna) vaccine, is the most effective vaccine in the autoimmune population. There was minimal induction of either disease flares or autoantibodies by vaccination and no significant effect of pre-existing anti-type I interferon antibodies on either vaccine response or breakthrough infections. The low frequency of breakthrough infections and lack of SARS-CoV-2-related deaths suggest that T cell immunity contributes to protection in autoimmune disease.