Inactivation of CALR potentiates antitumor immunity. (A) Principal component analysis of sgRNA abundance under each condition of the in vivo screens. (B) Images of dissected tumor from the anti-PD-1 and CD8 depletion treatment groups. (C) Effect of sgRNAs on cell proliferation. LFC of sgRNAs in LLC cell culture in vitro at day 10 compared with day 5 is shown. Dark gray lines represent control sgRNAs. Blue and red lines represent depleted and enriched sgRNAs. (D and E) Western blots showing the KO of CALR (D) and PDIA3 (E) in LLC cells. β-tubulin was used as an endogenous control. Results are representative of two independent experiments. (F) Number of immune cells (CD45⁺, CD3⁺, CD4⁺, CD8⁺, NK1.1⁺) infiltrating Calr KO and control LLC tumor, analyzed by flow cytometry. Data are presented as the mean ± SD. ns, not significant; *P < 0.05; **P < 0.01 by an unpaired t test. (G) Percentage of granzyme B⁺ CD8⁺ T cells and granzyme B⁺ NK cells within the total CD8⁺ T cell and NK cell populations, as measured by flow cytometry in Calr KO and control LLC tumor. Data are presented as the mean ± SD. **P < 0.01, *** P < 0.001 by an unpaired t test. (H) Percentage and number of regulatory T cells (CD4⁺ Foxp3⁺) in Calr KO and control LLC tumor measured by flow cytometry. Data are presented as the mean ± SD. ns, not significant by an unpaired t test. (I) Number of macrophage and DC in Calr KO and control LLC tumor measured by flow cytometry. Data are presented as the mean ± SD. *P < 0.05 by an unpaired t test. (J) Representative flow cytometry plots showing Qa1 (H2-T23) expression levels in H2-T23 KO and control LLC, MC38, and B16F10 cells, respectively. LFC, log₂ fold change. Source data are available for this figure: SourceData FS1.