PRDM1 and autoimmune pancreatitis: Significantly, we observed that the genes PRDM1 and SIX5 were markedly upregulated in the plasmablasts, IgG4‐positive plasma cells, and PRDM1‐positive plasma cells, suggesting their potential role in the pathogenesis of type 1 AIP (Figure 3G; Figure S3A–C, Supporting Information).