Persistence of anti-Desmoglein 3 Antibodies in Patients with Pemphigus Vulgaris in Clinical Remission is Associated with Restricted Isotype Diversity and Desmoglein 3 Ectodomain Recognition

In pemphigus vulgaris, baseline severity and relapse correlate with anti-DSG3 antibodies targeting both EC1-3 and EC4-5 and involving multiple IgG subclasses (2-3 subclasses in 81% of cases). In contrast, patients in clinical remission despite persistent anti-DSG3 antibodies show limited EC recognition and predominantly single IgG subclass responses, with lower frequencies of antibody-secreting cells and reduced in vitro keratinocyte dissociation.