A-C) B cell response in the absence of an antigen in terms of A) number B220+GL7+ cells, B) intensity of EZH2 expression and C) the number of B220+EZH2+H3k27Me3+ B cells on day 4 of ex vivo PEG-4MAL organoid culture with 40LB and IL-4. D-H) Response to membrane-bound and soluble antigen in terms of D) percent B220+GL7+ cells, E) percent B220+EZH2+ cells, F) percent B220+EZH2+H3k27me3+ cells, G) intensity of histone methylation, and H) percent B220+BCL6+ cells on day 8 of ex vivo organoid culture using B cells derived from aged mice. Data represent mean ± S.E.M. Significance determined via unpaired, non-parametric Mann Whitney t-test; N=5. *p<0.05, **p<0.01, ns denotes no significance.