Fetal thymic ontogeny in CCR9-deficient mice.

(A) The number of lymphoid cells found in CCR9-deficient (□) and wild-type (■) thymi are represented at different ages of embryonic life. (B) CD4/CD8 staining profiles on total thymocytes from wild-type and from CCR9-deficient mice at different ages of embryonic life. The percentage of cells within each quadrant is indicated in the lower-right panel.