KGF^-/-mice have intact T-cell development in the thymus. (A) Nine- to 12-week-old KGF^-/-, KGF^+/-, and WT controls (B6.129) were killed, and thymic, splenic, and BM cellularities were determined. (B-D) Ten- to 12-week-old KGF^-/- and KGF^+/- mice were killed and stained with anti-CD4, -CD8, -CD3, -CD44, and -CD25 antibodies, and thymic subpopulations were determined (DP, CD4⁺CD8⁺; DN, CD4^-CD8^-; DN1, CD44⁺CD25^-CD4^-CD8^-CD3^-; DN2, CD44⁺CD25⁺CD4^-CD8^-CD3^-; DN3, CD44^-CD25⁺CD4^-CD8^-CD3^-; DN4, CD44^-CD25^-CD4^-CD8^-CD3^-). (E) Thymic stromal cell populations were determined in KGF^-/- and KGF^+/- mice (according to the protocol described in “Materials and methods”). (F) Splenocytes from KGF^-/- and KGF^+/- mice were stained with CD4^- and CD8^- antibodies, and total CD4⁺ and CD8⁺ T-cell numbers were determined by flow cytometric analyses and splenic counts. (G) Peripheral lymph node (axillary and inguinal) cellularities of KGF^-/-, KGF^+/-, and WT mice were determined. (H-I) Bone marrow cells from KGF^-/- and KGF^+/- mice were stained with lineage-specific antibodies (anti-CD3, -CD11b, -Gr-1, -B220, and -NK1.1), anti-C-kit, and anti-SCA-1 antibodies. Stem cell populations were determined by multicolor flow cytometric analysis of lineage-negative cells, and the BM cell count from one mouse leg. Values represent mean (± SEM) and n = 6 to 12 mice per group. ^*P < .05.