树突状细胞在人皮肤黑色素瘤组织中抗原提呈效应的形态学观察

Morphological Observation of the Tumor Antigen Presenting Effect of the Dendritic Cells in Human Skin Melanoma

目的探讨人皮肤黑色素瘤组织中肿瘤浸润树突状细胞（TIDC）的抗肿瘤效应。方法采用光镜、透射电镜和免疫组化方法观察19例手术切除的人皮肤黑色素瘤中TIDC和肿瘤浸润淋巴细胞（TIL）抗肿瘤效应的形态学表现。结果早期人皮肤黑色素瘤组织中的类高内皮微静脉和淋巴管内、外均可见大量淋巴细胞和树突状细胞集聚和迁移；病变早期TIDC和TIL浸润比晚期明显（P〈0．01）。透射电镜下，TIDC大致有两种形态。一种TIDC体积大，表面有许多树枝状突起，核不规则，胞浆内有丰富的细胞器；另一种TIDC突起较少，细胞器也较少。TIDC与肿瘤细胞、TIDC与TIL、TIL与TIL、TIL与肿瘤细胞之间存在多种形式的膜接触。与TIL接触的肿瘤细胞呈凋亡状态。晚期病变组织中TIDC与TIL数量明显减少，于癌巢内常见凋亡的TIDC与TIL。结论人皮肤黑色素瘤组织中存在不同形态的TIDC与TIL，并通过类高内皮微静脉和淋巴管迁移；TIDC、TIL、癌细胞彼此密切作用，在肿瘤局部即可发生抗肿瘤免疫应答反应，反应程度与肿瘤进展呈负相关。

Objective To evaluate the anti-tumor effects of the tumor-infiltrating dendritic cells （TIDC） in human skin melanoma tissue. Methods The morphological characteristics and distributions of TIDCs and tumor-infiltrating lymphoeytes （TIL） in 19 human melanoma specimens were observed by light and electron microscopies and examined by immunohistoehemistry staining. Results Inside and outside the high endothelium venule-like blood vessels and lymphatic vessels in the early stage of melanoma tissues, there were a lot of lymphoeytes and DCs passing through the wall of the vessels and gathering around the vessels. TIDCs and TILs infiltrated more severely in the early stage of melanoma than that in the late stage（P 〈0.01 ）. There were two types of TIDCs observed by transmission electron microscope. One had big nucleus with irregular shape, increased volume, many dendritic protrusions on its surface, and a large amount of cell organelles in its cytoplasma. The other was short of dendritic protrusions and organelles. There were different cell contacts between TIDC and cancer cell, TIDC and TIL, TIL and TIL , and TIL and cancer cell. Apoptosis could be observed in the cancer cell connected to TIL. In late stage it could be observed that the number of TIDCs and TILs decreased apparently and apoptosis happened in cancer nest. Conclusion： There were a variety of TIDCs and TILs in human melanoma tissue, and those cells could immigrate through high endothelium yenule-like blood vessel and lymphatic vessel. The interactions among the TIDC, TIL, and cancer cells were suggested that TIDCs and TILs could directly cause anti-tumor immune response in cancer tissue. There was a negative correlation between the capacity of immune response and the progress of cancer.