Decitabine treatment abrogates formation of GCs in mice. Twenty C57/BL6 mice were immunized with SRBCs and subjected to daily intraperitoneal injections of water (A), PBS solution (ie, vehicle, B), 15 mg/m² decitabine (C) or 30 mg/m² decitabine (D). Formalin fixed paraffin embedded splenic tissue recovered at day 10 was examined by immunohistochemistry for B220, PNA, Ki67 and TUNEL. (E) The histogram represents the quantitative assessment of primary follicle and GC size as assessed by immunohistochemistry staining in all animals.