Figure 1
Ex vivo phenotypic analysis of regulatory CD4+Foxp3+ T cells in colorectal cancer (CRC) patients. (a) Representative bivariate flow cytometry plots showing Foxp3 (forkhead box P3) expression on live CD4+ T cells obtained from matched peripheral blood, unaffected colon, and colorectal tumor samples. (b) Percentage of live CD4+ T cells expressing Foxp3 in peripheral blood mononuclear cell (PBMC) samples (n=6) from age-matched healthy donors (HD; mean age, 71 years), and PBMC, unaffected colon, and tumor samples from CRC patients (n=14; mean age, 72 years). (c, d) Intracellular expression of the (c) Helios transcription factor and (d) cell surface expression of ICOS were assessed on CD4+Foxp3+ regulatory T cell (Tregs; ▴) and CD4+Foxp3− T cells (▪) isolated from blood (PBMC), unaffected colon, and tumor samples from CRC patients. Significant differences are indicated: *P<0.05, ***P<0.001. (e) Linear regression comparing the percentage of intratumoral CD4+ T cells expressing inducible T-cell costimulator (ICOS) with the percentage of intratumoral CD4+Foxp3+ Tregs.
