Clinical and Immunological Impact of Booster Immunization With Recombinant mRNA Vaccines for SARS-CoV-2 in Patients With Pemphigus and Bullous Pemphigoid

The study analyzed the immunological and clinical effects of mRNA booster vaccinations for SARS-CoV-2 in a group of 9 patients with pemphigus, 4 with bullous pemphigoid, and 5 healthy individuals. The participants were monitored at baseline, and after two and four weeks of mRNA vaccination. The results showed that the booster vaccination increased anti-spike protein IgG, while tetanustoxoid igC and skin-specific autoantibody titers were not or minimally affected. An increase in Th1/Th17.1 cells was observed, along with an increase in the intracellular production of IFN-γ, IL-4 and IL-21 in peripheral T cells of pemphigus patients. Importantly, the clinical activity in both remittent patients and in patients with active disease remained stable. Therefore, mRNA vaccines induced a specific activation of the humoral system with production of protective antibodies against the Sars-CoV-2 spike protein without affecting autoimmune disease activity in patients with pemphigus and bullous pemphigoid.