CTLA4 and colorectal cancer: We obtained 12 CD4+ T-cell clusters (Figure 6B), namely, CCR7, ANXA1, GNLY, TCF7, CXCR6, CXCR5, GZMK, IL23R, CXCL13, FOXP3, IL10, and CTLA4. CD8+ T-cells were divided into 8 clusters (Figure 6C), namely, LEF1, GPR183, CX3CR1, GZMK, CD6, CD160, LAYN, and SLC4A10. To explore the colorectal cancer specificity of cell types, we calculated the cell numbers of colorectal cancer patients with their immune cell types and the cell proportions (Supplementary Figure S2) and found that Mapk14 expression significantly differed in CRC patients with different CD4/CD8 cell types (Figure 6D).