AIM To investigate the abundance and potential functions of LAP^+CD4^+ T cells in colorectal cancer(CRC). METHODS Proportions of LAP^+CD4^+ T cells were examined in peripheral blood and tumor/paratumor tissues of CRC ...AIM To investigate the abundance and potential functions of LAP^+CD4^+ T cells in colorectal cancer(CRC). METHODS Proportions of LAP^+CD4^+ T cells were examined in peripheral blood and tumor/paratumor tissues of CRC patients and healthy controls using flow cytometry. Expression of phenotypic markers such as forkhead box(Fox)p3, cytotoxic T-lymphocyte-associated protein(CTLA)-4, chemokine CC receptor (CCR)4 and CCR5 was measured using flow cytometry. LAP^-CD4^+ and LAP^+CD4^+ T cells were isolated using a magnetic cellsorting system and cell purity was analyzed by flow cytometry. Real-time quantitative polymerase chain reaction was used to measure expression of cytokines interleukin (IL)-10 and transforming growth factor(TGF)-β.RESULTS The proportion of LAP^+CD4^+ T cells was significantly higher in peripheral blood from patients (9.44% ± 3.18%) than healthy controls (1.49% ± 1.00%, P < 0.001). Among patients, the proportion of LAP^+CD4^+ T cells was significantly higher in tumor tissues(11.76% ± 3.74%) compared with paratumor tissues (3.87% ± 1.64%, P < 0.001). We also observed positive correlations between the proportion of LAP^+CD4^+ T cells and TNM stage(P < 0.001), distant metastasis(P < 0.001) and serum level of carcinoembryonic antigen(P < 0.05). Magnetic-activated cell sorting gave an overall enrichment of LAP^+CD4^+ T cells (95.02% ± 2.87%), which was similar for LAP^-CD4^+ T cells(94.75% ± 2.76%). In contrast to LAP^-CD4^+ T cells, LAP^+CD4^+ T cells showed lower Foxp3 expression but significantly higher levels of CTLA-4, CCR4 and CCR5(P < 0.01). LAP^+CD4^+ T cells expressed significantly larger amounts of IL-10 and TGF-β but lower levels of IL-2, IL-4, IL-17 and interferon-γ, compared with LAPCD4+ T cells.CONCLUSION LAP^+CD4^+ T cells accumulated in the tumor microenvironment of CRC patients and were involved in immune evasion mediated by IL-10 and TGF-β.展开更多
基金国家自然科学基金(81260316)；2014年广西研究生教育创新计划资助项目( YCBZ2014032)Fund programsNational Natural Science Foundation of China (81260316)；The Graduate Creativity Education Project of Guangxi Autonomous Region
基金Supported by the National Natural Science Foundation of China,No.81260316
文摘AIM To investigate the abundance and potential functions of LAP^+CD4^+ T cells in colorectal cancer(CRC). METHODS Proportions of LAP^+CD4^+ T cells were examined in peripheral blood and tumor/paratumor tissues of CRC patients and healthy controls using flow cytometry. Expression of phenotypic markers such as forkhead box(Fox)p3, cytotoxic T-lymphocyte-associated protein(CTLA)-4, chemokine CC receptor (CCR)4 and CCR5 was measured using flow cytometry. LAP^-CD4^+ and LAP^+CD4^+ T cells were isolated using a magnetic cellsorting system and cell purity was analyzed by flow cytometry. Real-time quantitative polymerase chain reaction was used to measure expression of cytokines interleukin (IL)-10 and transforming growth factor(TGF)-β.RESULTS The proportion of LAP^+CD4^+ T cells was significantly higher in peripheral blood from patients (9.44% ± 3.18%) than healthy controls (1.49% ± 1.00%, P < 0.001). Among patients, the proportion of LAP^+CD4^+ T cells was significantly higher in tumor tissues(11.76% ± 3.74%) compared with paratumor tissues (3.87% ± 1.64%, P < 0.001). We also observed positive correlations between the proportion of LAP^+CD4^+ T cells and TNM stage(P < 0.001), distant metastasis(P < 0.001) and serum level of carcinoembryonic antigen(P < 0.05). Magnetic-activated cell sorting gave an overall enrichment of LAP^+CD4^+ T cells (95.02% ± 2.87%), which was similar for LAP^-CD4^+ T cells(94.75% ± 2.76%). In contrast to LAP^-CD4^+ T cells, LAP^+CD4^+ T cells showed lower Foxp3 expression but significantly higher levels of CTLA-4, CCR4 and CCR5(P < 0.01). LAP^+CD4^+ T cells expressed significantly larger amounts of IL-10 and TGF-β but lower levels of IL-2, IL-4, IL-17 and interferon-γ, compared with LAPCD4+ T cells.CONCLUSION LAP^+CD4^+ T cells accumulated in the tumor microenvironment of CRC patients and were involved in immune evasion mediated by IL-10 and TGF-β.
