Reduction in the number of GC B cells in immunized Dnmt1 hypomorphic mice. (A) Mononuclear splenocytes were purified 10 days after immunization with SRBC from WT, Dnmt1R/⁺ and Dnmt1N/⁺ mice and stained with 7-AAD/ B220/GL7/FAS. The percentage of GL7⁺ FAS⁺ cells reflects the abundance of GC B cells in the various animals. (B) The results from panel A are represented as a histogram depicting the percentage of GC B cells for each of the mice analyzed by flow cytometry.