大鼠肝癌组织中巨噬细胞与细胞毒性T细胞关系

Relationship between tumor associated macrophages and cytotoxic T lymphocytes in rat liver carcinoma

目的观察大鼠肝癌组织中巨噬细胞对细胞毒性T细胞浸润和凋亡的影响。方法构建Wistar大鼠Walker-256肝癌模型，将大鼠分为3组：A组（腹腔注射氯磷酸盐脂质体）、B组（腹腔注射PBS脂质体）、C组（腹腔注射生理盐水）。12d后摘取肿瘤组织，测量肿瘤大小、免疫组织化学检测肿瘤组织中浸润的CD68、CD163、CD8及GranzymeB阳性细胞个数；CD8与TUNEL双标方法检测肿瘤组织中T细胞的凋亡。结果（1）A、B、C3组肿瘤体积比较，差异均无统计学意义（P〉0．05）。（2）A、B、C 3组中，CD68阳性细胞个数在A、B组之间比较；CD163阳性细胞个数在A、B组之间比较；CD8阳性细胞个数在A、B组，A、c组之间比较；Granzyme阳性细胞个数在A、c组之间比较，差异有统计学意义（P〈0．05）。其余各组间比较，差异无统计学意义（P〉0．05）。其中，CD68、CD163阳性细胞个数在A组明显少于B、C组；而CD8、GranzymeB阳性细胞个数在A组明显多于B、C组。（3）相关分析显示，针对全部肿瘤组织，CD68与CD8阳性细胞之间，CD163与GranzymeB阳性细胞之间呈负相关，差异有统计学意义（P〈0．05）。CD68与GranzymeB阳性细胞之间，CD8与CD163阳性细胞之间无明显相关。（4）A、B、C3组中T细胞（CD8）凋亡率在A、C组之间比较，差异有统计学意义（P〈0．05）；其余各组间比较，差异无统计学意义（P〉0．05）。A组T细胞凋亡率明显低于B、C组。结论氯磷酸盐脂质体可有效清除大鼠肝癌组织中巨噬细胞。巨噬细胞清除后，细胞毒性T细胞的浸润增多、凋亡减少。肿瘤巨噬细胞通过促进细胞毒性T细胞凋亡而抑制其对肿瘤细胞的杀伤活性，在肿瘤发展中起重要作用。

Objective To investigate the influence of tumor associated macrophages on cytotoxic T lymphocytes （CTL） infiltration and apoptosis in rat liver carcinoma. Methods Walker-256 Wistar rat heparoma models were established. Then rats were randomly divided into three groups： group A （clodronatelipsomes by intraperitoneal injection） ; group B （PBS-lipsomes by intraperitoneal injection） ; group C （norreal saline by intraperitoneal injection）. Animals were killed at the 12th day after treatment. The tumor volume was measured, and the number of positive cells of CD68, CDS, CD163, and Granzyme B was detected by using immunohistochemical method, respectively. The apoptosis of CD8^＋ T cells in tumor tissues was tested by the method of double staining with immunohistochemistry and TUNEL. Results （ 1 ） There was no significant difference in tumor volume among groups A, B and C （P 〉0. 05） ; （2） There was significant difference in CD68 positive cells between groups A and B, CDE163 positive cells between groups A and B, CD8 positive cells between group A and B or between groups A and C; and Granzyme B positive cells between groups A and C （all P 〈0. 05）. The number of CD68 and CD163 positive cells in group A was less than in groups B and C. The number of CD8 and Granzyme B positive cells in group A was more than in groups B and C ; （3） There was a negative correlation not only between the positive cells of CD68 and CDS, but also between CD163 and Granzyme B positive cells. However, there was no correlation between the positive cells of CD68 and Granzyme B, as well as between the positive cells of CD163 and CD8 ; （4） There was significant difference in apoptosis rate of CD8 T ceils between groups A and C group （P 〈 0. 05）. Apoptosis rate of CD8 T cells in group A was lower than in groups B and C. Conclusion Clodronate liposome can deplete macrophages of rat liver carcinoma tissues effectively. After macrophages were depleted, the number of CTL was increased and the apoptosis rate of CTL was decreased in rat liver carcinoma. Tumor associated macrophages can promote apoptosis and inhibit killing activity of cytotoxicity T lymphocyte, and play an important role in tumor development.