Bone marrow of ERK1/2 mice contains increased numbers of mature myeloid and lymphoid cells with retention of ERK2 expression in monocytes but not granulocytes.

(A) Bone marrow cells from LysM and ERK1/2 mice (six of each) were analyzed by ex vivo flow cytometry to assess lineage-committed cells. (B-I) Cell numbers were calculated from total bone marrow cell counts and the percentage of each population in the gate. (J) Neutrophils (CD11b^hi Gr-1^hi) and monocytes (CD11b⁺ Gr–1^-) from LysM and ERK1/2 bone marrow were collected by FACS and analyzed by Western blotting for expression of ERK and β-actin. Data are expressed as means ± standard deviations. Results are representative of two independent experiments.