Figure 2. MEF2C supports efficient peripheral B-cell recovery on sub-lethal irradiation.

(a) Experimental design of haematopoietic ablation by sub-lethal irradiation: Vav-Cre Mef2c^fl/fl and control mice received 6 Gy of total body irradiation. Peripheral blood was collected for complete blood cytometry (CBC) and flow cytometric analysis at day 2 and weeks 2, 4 and 6. Mice were killed and spleens were analysed by flow cytometry at day 2, and weeks 2 and 6. (b) Representative flow cytometric analysis of peripheral blood B cells revealed defective B-cell recovery in Mef2c-deficient mice. (c) Quantification of peripheral blood lineage cell count (WBC count from CBC was multiplied with each lineage-specific percentage obtained from flow cytometry) documents that loss of Mef2c compromised the recovery of B cells while T and myeloid cells were not affected. (d) Flow cytometric analysis of spleen B cells in both Vav-Cre Mef2c^fl/fl and control mice after irradiation revealed defective B-cell recovery in Mef2c-deficient spleens. All mice were analysed at 7–10 months of age and both male and female mice were included. Day 2: n=4 mice, data shown are the mean±s.d. of two independent experiments; other time points: n≥5, data shown are the mean±s.d. of three or more independent experiments. NS, not significant, *P<0.05, **P<0.01 and ***P<0.001, unpaired t-test.