236079.fig.003a
(a)
236079.fig.003b
(b)
Figure 3: Histopathological examination of Case 2. (a) Small-sized gland ducts with plasma cell and eosinophilic leukocyte infiltrations (H&E stain × 40). (b) IgG4-positive plasma cells (stained with IgG4 monoclonal antibody × 40). Mouse monoclonal antibody to human IgG4 (clone, HP6025; dilution, 1 : 100; Zymed Laboratories Inc., Calif, USA).