Youssef Manal M S, Paish Emma C, Murray J Clifford, Farag Naglaa M, Saleh Khaled, Ellis I O
Egypt J Immunol. 2015;22(1):19-28.
Dysfunction of the immune system in colorectal cancer (CRC) can be due to a number of reasons including apoptosis of tumour infiltrating lymphocytes (TILs). The aims of this study was to investigate TILs in colorectal cancer and characterize apoptosis of TILs using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay for detecting DNA fragments. We used monoclonal antibodies (mAbs) to T lymphocytes to detect TILs and double immunohistochemistry to assess apoptosis. T lymphocytes were detected in the immune infiltrate in CRC. TUNEL staining disclosed a high level of cell death among TILs. Apoptosis of T lymphocytes showed significant correlation with Dukes' stage (P = 0.02), lymphatic metastasis (P = 0.03), vascular metastasis (P = 0.01), lymph node metastasis (P = 0.02) and age of patient (P = 0.01). In conclusion, CRC may elude immunological surveillance by inducing apoptosis of TILs.
结直肠癌（CRC）中免疫系统功能障碍可能由多种原因引起，包括肿瘤浸润淋巴细胞（TILs）的凋亡。本研究的目的是调查结直肠癌中的TILs，并使用末端脱氧核苷酸转移酶dUTP缺口末端标记（TUNEL）法检测DNA片段来表征TILs的凋亡。我们使用针对T淋巴细胞的单克隆抗体（mAb）来检测TILs，并采用双重免疫组织化学法评估凋亡情况。在CRC的免疫浸润中检测到了T淋巴细胞。TUNEL染色显示TILs中有高水平的细胞死亡。T淋巴细胞的凋亡与Dukes分期（P = 0.02）、淋巴转移（P = 0.03）、血管转移（P = 0.01）、淋巴结转移（P = 0.02）及患者年龄（P = 0.01）显著相关。总之，CRC可能通过诱导TILs凋亡来逃避免疫监视。
