树突状细胞在食管癌T细胞抗肿瘤免疫中的作用

The Role of Dendritic Cells in Activation of T Cell Mediated Antitumor Immunity in Esophageal Carcinoma

目的：了解食管癌组织中树突状细胞（DCs）在肿瘤浸润性T淋巴细胞激活中的作用。方法：采用免疫组化和RT－PCR的方法，对46例食管癌手术标本中DCs（CD1a）、T细胞亚群（CD3、CD4、CD8、CD25）及共刺激因子B7进行检测。结果：癌组织中的DCs与CD3＋、CD4＋T细胞有相关性，与CD8＋、CD25＋T细胞无明显关系，且B7mRNA表达均为阴性。结论：食管癌中DCs不一定能有效地激活T细胞，其中B7基因表达受抑制，可能是不能有效激活T淋巴细胞，产生免疫耐受的原因之一。

Objective To study the role of DCs in activation of infiltrating T lymphocytes in esophageal carcinoma． Methods Forty－six specdimens from patients with esophageal carcinoma were studied for DCs CD10 the subsets of tumor infiltrating T lymphocytes CD3 CD4 CD8 CD25 and costimulatory B7 using monoclonal antibodies by immunohistochemistry staining LSAB method and reverse transcription polymerase chain reaction RT－PCR． Results A significant correlation was found between CD1a＋ DCs and CD3＋ CD4 T lymphocytes but no remarkable correlation between CD1a＋ DCs and CD8＋ CD25＋ T lymphocytes． No specific B7mRNA expression was found in all specimens． Conclusion DCs may not activate T lymphocytes efficiently． B7 gene expression at low level or deficiency in esophageal carcinoma may be one of the important reasons of failure to activate lymphocyte and induce the immunmosuppression．