Fig. 4: p53 controls GC B cell proliferation during MHV68 latency establishment.

a Quantification of GC B cells undergoing DNA replication on day 16 after mock infection or infection of p53^-/- and p53^+/+ mice with MHV68. EdU was injected intraperitoneally 2 h prior to sacrifice to label newly replicated DNA. Click chemistry was performed and EdU + GC B cells (gated as CD19⁺/B220⁺/GL7⁺/CD38^lo) were detected by flow cytometry. Total (left panel) and percent EdU + GC B cells per spleen (right panel) are shown. Each dot represents an individual mouse, n = 4. b Flow cytometric quantification of GC B cells (gated as CD19⁺B220⁺GL7^hiCD38^lo) undergoing apoptosis on day 16 after infection of p53^-/- and p53^+/+ mice with MHV68. Apoptotic cells were identified as active caspase 3/7⁺ after ex vivo staining. Gating strategies are shown in Supplementary Fig. 10. Data represent means +/− SEM. Mann-Whitney unpaired two-sided t test, * p < 0.05, **p < 0.005. Each dot represents an individual mouse, n = 4-5.