Fig. 2: BMF features of AA mouse model were majorly induced by CD8⁺ T cells.

A Experimental scheme of generating AA mice. TBI irradiated (5.0 Gy) CbyB6F1 mice were injected with 5 × 10⁶ CD4⁺ or CD8⁺ T cells from B6 mice lymph node via tail vein injection. B Images of representative H&E staining of murine femurs in different groups were taken under microscope. Scale bar:100 μm. C The survival curves were determined in pre-irradiated (5.0 Gy) CbyB6F1 mice (TBI), TBI mice injected with 5 × 10⁶ CD4⁺ T cells (TBI + CD4⁺) or CD8⁺ T cells (TBI + CD8⁺). N = 10 in each group. Data were pooled from three independent experiments. ***P < 0.001. D Blood counts of TBI mice, TBI mice injected with CD4⁺T cells or CD8⁺ T cells. Data were presented as the mean ± SD. N = 5 in each group at each time point. E Representative in vivo image of skull BM in living mice injected with CD4⁺ T cells or CD8⁺ T cells. Pre-irradiated CbyB6F1 mice received 5 × 10⁶ GFP⁺CD4⁺ or GFP⁺CD8⁺ T cells. Vessel was stained with dextran-CY5 (blue) by tail vein injection. GFP⁺ infiltrating lymphocytes (green) were visualized under microscope. Scale bar:100 μm. F Percentage of the area showing GFP⁺ T cells per field in the image of intravital skull BM cavity from the mice injected with CD4⁺ T cells or CD8⁺ T cells on day14. Data were presented as the mean ± SD. N = 5 in each group. *P < 0.05. FACs analyses of representative dot plot (G) and mean±SD (H) of CD4⁺ T cells and CD8⁺ T cells in BM of TBI mice, TBI mice injected with CD4⁺T cells, and TBI mice injected with CD8⁺ T cells on day14. FACs analyses of representative dot plot (I) and mean±SD (J) of CD4⁺ T cells and CD8⁺ T cells in the spleen of TBI mice, TBI mice injected with CD4⁺T cells and TBI mice injected with CD8⁺ T cells on day14. N = 5 in each group. ***P < 0.001.