MALD1 participate in immune reactions. Top, chronic gastritis in a MALD1 case. A, lymphoid follicles formation in the lamina propria (HE; ×20). B, main image: numerous lymphoid cells overexpressing cyclin D1 in the mantle zone (IHC; ×20); inset: boundary between the germinal center and mantle zone (IHC; ×700). C, abundant H. pylori in the lumen of the gastric pits (Giemsa; ×900). Bottom, posttreatment study of the same case. D, mild mucosal atrophy without inflammation (HE; ×40). E, absence of lymphoid cells expressing cyclin D1 (IHC; ×40). F, absence of H. pylori in the lumen of the gastric pits (Giemsa; ×900).