The Relationship Between M2-macrophages Infiltration And Subtype Of T-lymphocytes In Human Cervical Carcinoma And Its Regulation Role On T-cells

Objective: To investigate the distribution of macrophages and M2-macrophages and their relationship with tumor-infiltrating FOXP3+T and CD8+T as well as their correlation with clinicopathological features. To detect the expression of B7-H4 and B7-DC by macrophages and M2-macrophages in human cervical carcinoma. Futher to determine the effect of recombinant human B7-H4 protein on the immune regulation role of cervical cancer patients in vitro.Methods: The distribution of macrophage and M2-macrophage were determined in 60 cases of cervical carcinoma, 10 cases of high-grade squamous intraepithelial lesion and 10 cases of cervical tissue using immunohistochemical staining. Infiltrating number of CD8+T cells and its Granzyme B production as well as FOXP3+T cells, the expression of B7-DC and B7-H4 by macrophage and M2-macrophage were analyzed through immunofluorescent double-staining. Peripheral blood T cells of cervical carcinoma patients were co-cultured with B7-H4 or PBS for 48 h as B7-H4 and blank group, then Ki67 positive rates, cell subtypes and apoptosis were detected by flow cytometry.Results:(1) Macrophage and M2-macrophage were distributed densely in cervical cancer tissue, the number of them were significantly higher than that of HSIL and cervical tissue(P=0.000, P=0.000; P=0.000, P=0.000). In addition, the number of infiltrating macrophage was higher than that of M2-macrophage(P=0.000).(2) The number of macrophages and M2-macrophages increased in cases with lymphatic metastasis and cancer embolus, when compared with those cases without lymphatic metastasis and cancer embolus(P=0.035, P=0.019; P=0.001, P=0.011). But there were no significant correlation between macrophage or M2-macrophage and age, invasion depth and histological types.(3) In 60 cases of cervical carcinoma, the number of CD8+T, FOXP3+T and Granzyme B positive cells increased, which were separately 126.75±78.19, 84.45±37.90 and 72.4±36.51.(4) In 60 cases of cervical carcinoma, significantly positive correlations were found between macrophages or M2-macrophages and FOXP3+T(r=0.317, P=0.014; r=0.294, P=0.023). However there were no significant correlations between macrophage or M2-macrophage and CD8+T as well as Granzyme B production(P>0.05).(5) B7-H4 but not B7-DC was expressed by most M2-macrophages. Neither B7-H4 nor B7-DC was expressed by macrophages.(6) After co-cultured with B7-H4 protein for 48 h, the Ki67 positive rates of CD4+T and CD8+T were(11.45±2.24) % and(2.78±1.01) %, while the blank group were(10.30±1.72) % and(3.48±1.23) %. The ratio of CD4+T/CD3+T were(42.1±1.9) % and(39.8±2.6) %, the proportion of CD8+T/CD3+T were(36.1±3.7) % and(56.2±2.2) %(P<0.05), the ratio of CD4+T/CD8+T were 1.17 and 0.71, the percentage of FOXP3+T cells were 55.4% and 52.4% in B7-H4 group and blank group. The total apoptotic rates of T-cells were(27.8±3.29) % and(25.1±1.98) %, the apoptosis of CD8+T were(36.1±2.34) % and(28.0±2.36) %(P<0.05), the apoptotic rates of CD4+T were(26.9±2.05) % and(24.8±2.17) % in B7-H4 group and blank group.Conclusion: The macrophage and M2-macrophage were distributed densely in cervical cancer, they were associated with higher numbers of tumor-infiltrating FOXP3+T lymphocytes as well as lymphatic metastasis and cancer embolus. In addition, M2-macrophage express B7-H4 which may promote CD8+T cells apoptosis, but has no significance on Tregs. M2-macrophage plays an important role on depressing anti-tumor immune response in microenvironment of cervical cancer.