Characterization of mature hematopoietic cell populations in Jam-C^−/− mice. (A) Total number of mononuclear cells in BM (femur and tibia of both hind legs) of wild-type and homozygous mice (n = 7). (B,C) Frequency of hematopoietic lineages in BM of wild-type and homozygous mice assessed by flow cytometry with antibodies against Ter119 (erythroid lineage), Gr-1 and CD11b (myeloid lineage), and B220 (B-cell lineage). (D) Enumeration of erythroid cells, B cells, and granulocytes in the BM of wild-type and homozygous mice. Shown are representative FACS profiles; the numbers on the plots indicate the frequency of cells in the indicated regions. Bar graphs indicate mean plus or minus SE. Significances are shown on the graph. **P ≤ .01.