Altered bone marrow erythropoiesis and elevated spleen erythropoiesis in aged Lyn+/up and Lynup/up mice. (A) Bone marrow BFU-E are reduced, whereas CFU-E numbers are increased in aged Lyn+/up and Lynup/up mice. Erythroid colony assays (BFU-E and CFU-E) of Lyn+/+, Lyn+/up, and Lynup/up bone marrow from mice 70 to 85 weeks of age (n ≥ 3, *P < .05, ns, not significant). (B) Comparison of maturing bone marrow erythroid cells from aged Lynup/up and Lyn+/+ mice. Representative flow cytometric analysis of Lyn+/+ (WT) and Lynup/up bone marrow cells of mice 70 to 85 weeks of age and enumerated as in Figure 2D. (C) Extramedullary erythropoiesis in spleen of aged Lyn+/up and Lynup/up mice. Erythroid colony assays (BFU-E and CFU-E) of Lyn+/+, Lyn+/up, and Lynup/up spleens from mice 70 to 85 weeks of age (n ≥ 3, **P < .01). (D) Elevated maturing erythroid cells in the spleen of aged Lynup/up mice. Representative flow cytometric analysis of spleen cells of Lyn+/+ (WT) and Lynup/up mice 70 to 85 weeks of age and enumerated as in B. Mean ± standard deviation is shown. Statistically significant (2-way ANOVA) differences are indicated (*P < .05).
