Fig. 1

TRM cells are enriched in rejecting allografts and secondary lymphoid organs. (A) The skin graft from BALB/c mice was transplanted to the back of C57 mice, and on day seven, the graft, spleen, peripheral blood, and draining lymph nodes were harvested. (B) The graft survival time after syngeneic(n = 6) and allogeneic(n = 6) skin transplantation. (C) Photos of C57 and BALB/c skin grafts in C57 recipient mice. (D) Hematoxylin and Eosin (HE), CD3, CD4, and CD8 immunohistochemistry of syngeneic and allogeneic grafts. (E) Flow cytometric analysis of changes in CD8⁺TRM cells in syngeneic and allogeneic grafts. (F) Immunohistochemistry of CD69 and CD103 in syngeneic and allogeneic grafts. Changes in immune checkpoint molecules PD-1 (G), TIGIT (H), and CTLA-4 (I) on CD8⁺ TRM cells in the grafts. Statistical analysis was performed using the t-test to compare the differences between groups. Bars represent mean ± SD from 10 independent experiments. Statistical significance is indicated by *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001; “ns” denotes no significant difference.