大肠癌组织中抗原递呈细胞改变的研究

The change of antigen-presenting cells in colorectal cancer

目的观察大肠癌组织局部抗原递呈细胞及淋巴细胞、CD8+的淋巴细胞数量的改变情况,探讨肠癌细胞逃避免疫监视的机制。方法用免疫组化的方法检测65例大肠癌组织、切端黏膜局部组织中树突状细胞(DC)及各类免疫细胞亚群数量,结合肠癌的临床病理资料进行综合分析。结果大肠癌组织中S-100阳性的DC数量低于切端黏膜,差异有显著统计学意义(=0.001);在肿瘤不同的Dukes分期及分级中,S-100阳性的DC数量比较差异无统计学意义。肠癌组织中淋巴细胞总数与其相应的切端黏膜细胞总数比较,差异无统计学意义(=0.066);淋巴细胞在高分化肠癌组织与中分化肠癌组织中数量比较,差异有统计学意义(=0.015),高分化肠癌组织与低分化肠癌组织中数量比较,差异有显著统计学意义(=0.006);在不同的Dukes分期中淋巴细胞总数比较,差异无统计学意义。肠癌组织中CD8+淋巴细胞数量与其相应的切端黏膜细胞数比较,差异无统计学意义(=0.328);在肿瘤不同的Dukes分期及分级中,CD8+淋巴细胞数量比较差异无统计学意义。结论大肠癌组织中局部的DC数量减少,反应了肿瘤组织抗原递呈功能降低,可能是肠癌细胞逃避机体的免疫监视的重要机制。

Objective To investigate the change of antigen-presenting cells and lymphoid cells in colorectal cancer. Methods Clinicopathologic data were analyzed in 65 cases. Antigen-presenting cells and lymphoid cells in colo- rectal cancer were studied by immunohistochemistry between colorectal cancer and histologically normal mucosa distant from cancer. S-100 and CD8 monoantibodies（MAbs） were used in this study. Results In colorectal cancer tissues, the number of S-100 dendritic cells was reduced, compared to that in histologically normal mucosa distant from cancer （P = 0.001） ; the number of lymphoid cells in poor differentiation colorectal cancer tissue was reduced compared to that in well differentiation colorectal cancer（P = 0.006）; the number of lymphoid cells in poor differentiation colorectal cancer tissue was reduced, compared to that in well differentiation colorectal cancer tissue（P = 0.006）. Conclusion The number of S-100 dendritic cells is reduced in the colorectal cancer. It may be one important mechanism by which colorectal cancer cells escape immune surveillance.