Fig 2: CD8+ T cells depletion experiments and ex vivo analysis of immune cells.a Primary (*p = 0.0345, ***p = 0.0001) and b distant (***p = 0.0001) tumor growth curves of CT26 colorectal bilateral tumor-bearing mice treated with Saline, Saline+RT, H@Gd-NCPs+RT and H@Gd-NCPs+RT + αCD8a, (n = 8 biologically independent animals). [Gd3+] = 30 mg kg−1, [Hemin] =12.5 mg kg−1 and [αCD8a] = 10 mg kg−1. Treatments were performed on days 0 and 6. X-ray radiation therapy was performed 6 h after nanomedicines intravenous injection (black arrow). RT 6 Gy × 2 with fractions delivered 6 days apart and only primary tumors received radiation therapy. Anti-CD8a antibody was treated via intraperitoneal injection 6 h after radiation therapy (red arrow). Data (a, b) were presented as mean ± SEM. c Primary (***p = 0.0001, ***p = 0.0001) and d distant (***p = 0.0001, ***p = 0.0001) CT26 tumor weight (n = 8 biologically independent animals). e, f Growth curves of e primary and f distant individual tumors in the H@Gd-NCPs + RT and H@Gd-NCPs + RT + αCD8a groups. g, h The percentages of CD8+ T cells in the g primary (***p = 0.0001, ***p = 0.0001) and h distant (***p = 0.0002, ***p = 0.0003) tumors analyzed by flow cytometry (n = 6 biologically independent animals). i The percentages of macrophages (F4/80+ and CD11b+) in the primary tumors analyzed by flow cytometry (n = 6 biologically independent animals). Tumor tissues (g–i) in different groups were harvested on day 18 for flow cytometry analysis. Data (c, d, g–i) were presented as mean ± SD. Two-sided Student’s t-test was used to calculate the statistical difference between two groups. N.S. represented non-significance, and *p < 0.05, ***p < 0.001. Source data are provided as a Source data file.

Fig 3: D665-G3c treatment induced permanent allograft acceptance.(A) Treatment protocol of D665 and G3c in mouse heart transplantation. D665 (250 μg per mouse) and G3c (250 μg per mouse) were intraperitoneally injected on days −3 and 0 sequentially. Heart transplantation was performed on day 0. (B) The survival of cardiac allografts in each group (n = 9 to 12 for each group). The graft survival of each group was evaluated using Kaplan-Meier curves and log-rank tests. ****P < 0.0001. (C) Representative hematoxylin and eosin staining of cardiac grafts in each treatment group on POD7 (n = 6 for each group). Scale bars, 100 μm. (D) A representative FCM analysis of CD4+CD25+Foxp3+ Treg cells in the splenocytes of each treatment group on POD3 and POD7. (E) A representative FCM analysis of IL-10/IFN-γ–co-producing CD4+ Tr1 cells in the splenocytes (SPs) and GILs of each treatment group on POD7 (n = 4 for each group). (F) A representative FCM analysis of CD4+ T and CD8+ T cells in the splenocytes and GILs of each treatment group on POD7 (n = 4 for each group). (G) Representative CD8 (blue), 5-bromo-2′-deoxyuridine (BrdU) (red), and type IV collagen (yellow) triple immunohistochemistry staining of heart grafts in each group on POD7 (n = 4 for each group). Scale bars, 100 μm. (H) Survival of cardiac allografts in each group (n = 6 for each group). The graft survival of each group was evaluated using Kaplan-Meier curves and log-rank tests. ***P < 0.001.

Fig 4: Colec11–/– mice exhibit less immunosuppressive TME.Tumors excised from Colec11+/+ (WT) or Colec11–/– (KO) mice (d14) were used for analyzing TME. (A–C) Tumor infiltrates analyzed by flow cytometry. (A) CD45+ cells. (B) Subsets of tumor-infiltrating leukocytes analyzed by flow cytometry. Data were analyzed by unpaired t test (n = 18 mice per group, pooled from 4 experiments). Each dot represents an individual mouse. (C) A bar chat representing proportion of subsets in CD45+ cells shown in B. (D) Representative microscopy images of immunochemical staining for CD11b (green)/CD3 (red)/DAPI (blue) and F4/80 (green)/CD3 (red)/DAPI (blue). Scale bar: 50 μm. (E) Representative microscopy images of immunochemical staining for CD8 (red)/DAPI (blue) in tumor edge and core areas. Scale bar: 50 μm. (F). qPCR analysis in tumor tissues. Data were analyzed by unpaired t test (n = 8 mice per group). *P < 0.05; **P < 0.01; ***P < 0.001; ****P < 0.0001.