肝癌微环境中CD4+CD25+Treg细胞与肿瘤免疫细胞的关系

[目的]探讨肝癌微环境中Treg细胞的数量增多与HCC临床分期晚的可能原因。[方法]双重酶标免疫组织化学方法检测52例HCC组织中CD4^＋CD25＋Treg细胞以及CD4^＋CD25-T（CD4^＋T）细胞分布，免疫组化EnVision法检测20例HCC组织中CD8＋T细胞分布。[结果]正常肝脏组织中未发现Treg细胞。HCC组织中Treg细胞数量较癌旁组织明显增多（P=0．000），且肝癌组织中Treg细胞的数量与其浸润性CD4＋T淋巴细胞的数量以及CD4＋T/CD8^＋T比值呈显著负相关（r=-0．539，P=0．014；r=-0．545，P=0．000），而与浸润性CD8^＋T淋巴细胞的数量无明显相关性（f=-0．403，P=0．078）。[结论]Treg细胞在体内可能通过细胞接触的方式抑制CD8^＋T淋巴细胞的增殖来抑制肿瘤局部的免疫，去除或减少HCC微环境中浸润件Tree细胞数量可能提高肿瘤局部免疫治疗效果。

Correlation between the Distribution of CD4+CD25+ Regulartory T (Treg) Cells and T-cell Infiltration in Microenvironment of Hepatocellular Carcinoma

[Purpose] To explore the causes of an increased prevalence of regulartory T(Treg) cells in microenvironment of hepatocellular carcinoma(HCC) which involved in TNM stage according to disease progression. [Methods] The CD4+CD25+ Treg and CD4+CD25-T (CD4+T) cells in the slides tissues of 52 cases with HCC were marked by Double-immunohistochemical, and CD8+T cells in the slides tissues of 20 cases with HCC by EnVision. [Results] There was no Treg cell in normal liver tissues. The number of Treg cells in the tissue of HCC was significantly more than that in the tissue of peri-cancer(P=0.000). The number of Treg cells in HCC tissue was negatively correlated to the ratio of CD4+T/CD8+T and CD4+T cells infiltration (r=-0.539,P=0.014;r=-0.545,P=0.000), however, with no correlation to CD8+T cells infiltration(r=-0.403,P=0.078). [Conclusions] Treg cells possibly suppress proliferation of CD4+T cells in a contact-dependent manner so that tumor cells can escape immune surveillance and result in invasion and progression. Functional deletion of tumor-infiltrating Treg cells in microenvironment of HCC can enhance tumor-specific immunotherapy.