C3 and neoplasm: Taken together, we have shown that in our cohort of patients, DPP4i-related BP is more likely to present with a noninflammatory BP phenotype, decreased peripheral and skin eosinophilia, significantly lower BP180 antibody titers, a lower proportion of C3 positivity, and negative indirect IF and BP230 antibodies, as compared to nonDPP4i-BP.