Analysis of the effects (mean + SEM) of ovx in WT and CD40L^−/− mice and TCRβ^−/− mice previously reconstituted with CD40L^−/− T cells. (A) Effects of ovx on the relative frequency of BM LSK cells. (B-C) Effect of ovx on the relative frequency of ST-HSPCs/MPP and LT-HSPCs. (D) Effect of ovx on the number of BM B cells, monocytes, erythroid cells, and granulocytes. (E-G) Effect of ovx on peripheral blood cell expansion after primary competitive repopulation. In these experiments, CD45.2 CD40L^−/− and control WT mice were killed after 2 weeks of ovx or sham operation. BM was then mixed with BM from intact CD45.1⁺ WT mice at a ratio of 1:2 (donor/ competitor) and injected into lethally irradiated CD45.1⁺ recipient mice. The percentage of CD11b⁺, GR-1⁺, and B220⁺ cells in the peripheral blood of lethally irradiated WT recipient mice are shown. Recipient mice received CD45.2⁺ BM donor cells from WT and CD40L^−/− mice previously subjected to sham operation or ovx mixed in a 1:2 ratio with CD45.1⁺ competitor BM cells from intact WT mice. (H-K) Survival analysis of WT mice transplanted with limiting number of BM cells derived from WT and CD40L^−/− mice. (H-J) Donor mice were intact WT or CD40L^−/− mice. Recipient mice were WT mice subjected to sham operation or ovx 2 weeks before the BM transplantation. (I-K) Donor mice were sham operated or ovx 2 weeks before the BM transplantation. Recipient mice were intact WT mice. n = 10 per group. *P < .05 compared with the corresponding sham-operated group.