As a measure of GC output we also analyzed the number of memory B cells in the spleen and plasma cells in the bone marrow at 60 days following LCMV-c13 infection and observed no difference in overall numbers between Cd4-cre+Cd2apF/F and control Cd2apF/F, suggesting enhanced acquisition of mutations rather than total output contributed to the phenotype (S4 Fig). The gene discussed is CD4; the disease is infection.