Fig. 2. Genetic ablation of HCK in myeloid cells promotes CD8⁺ T cell recruitment and activation.

(A) Flow cytometry quantification of CD4⁺ T cells, CD8⁺ T cells, and NK cells from subcutaneous MC38 tumors of WT and Hck^KO hosts treated as described in Fig. 1A. Each symbol represents an individual mouse. (B) Representative immunohistochemical staining for CD8⁺ T cells in subcutaneous MC38 tumors of WT and Hck^KO hosts treated as described in Fig. 1A. Scale bar, 100 μm. Quantification of staining per square micrometer tumor area is also shown. Each symbol represents an individual mouse. (C) qPCR analysis on FACS-purified tumor-associated CD45⁺TCRβ⁺CD8⁺ T cells for markers associated with immune cell activation. Cells were isolated from subcutaneous MC38 tumors of WT and Hck^KO hosts treated as described in Fig. 1A. n = 4 mice per group. (D and E) Subcutaneous MC38 tumor volume of WT and Hck^KO hosts following treatment with αPD1 and/or depleting antibodies against CD8 or NK1.1. Depletion antibodies were administered once every 3 days before subcutaneous MC38 tumor cell injection (total of three treatments) and continued until the experimental end point when tumors reached ≥600 mm³. n ≥ 10 mice per group. Data represent mean ± SEM; *P < 0.05, **P < 0.01, and ***P < 0.001, with statistical significance determined by one-way ANOVA followed by Tukey’s multiple comparison test.