Down-regulation of human leukocyte antigens class I on peripheral T lymphocytes and NK cells from subjects in region of high-incidence gastrointestinal tumor

• Published in: Chinese medical journal Vol. 124; no. 12; pp. 1813 - 1817
• Main Authors: Zhang, Zhi-Mian, Li, Ying-Jie, Guan, Xiao, Yang, Xiao-Yun, Gao, Xi-Mei, Yang, Xiao-Jing, Wang, Li-Shui, Zou, Xiong
• Format: Journal Article
• Language: English
• Published: China Department of Health Examination Center,Qilu Hospital of Shandong University, Jinan, Shandong 250012, China%Department of Laboratory Medicine,Qilu Hospital of Shandong University, Jinan, Shandong 250012, China 01.06.2011
• Subjects: Adult; Aged; Biomarkers, Tumor - analysis; Down-Regulation; Female; Gastrointestinal Neoplasms - immunology; Histocompatibility Antigens Class I - analysis; Humans; Killer Cells, Natural - immunology; Male; Middle Aged; NK细胞; T-Lymphocytes - immunology; 人类白细胞抗原; 发病率; 外周血T淋巴细胞; 外周血单个核细胞; 外周血单核细胞; 消化道肿瘤; 肿瘤标志物; T-lymphocytes; gastrointestinal neoplasms; histocompatibility antigens class I; killer cells,natural
• ISSN: 0366-6999; 2542-5641; 2542-5641
• DOI: 10.3760/cma.j.issn.0366-6999.2011.12.010

Background Many types of human tumors can suppress the immune system to enhance their survival. Loss or down-regulation of human leukocyte antigens （HLA） class I on tumors is considered to be a major mechanism of tumor immune escape. Our previous studies found that HLA class I on peripheral-blood mononuclear cells was significantly lower in gastric cancer patients. The present study made an analysis of HLA class I expression on peripheral-blood T lymphocytes and NK cells from subjects of Lijiadian village, a village with high-incidence gastrointestinal tumor. Methods A total of 181 villagers from Lijiadian village and 153 normal controls from the Department of Health Examination Center were enrolled in this study. Using a multi-tumor markers detection system, these villagers were divided into two groups： high-risk group （tumor markers positive group） and low-risk group （tumor markers negative group）. The percentage of T lymphocytes and NK cells and levels of HLA class I on their surface were determined in these subjects by flow cytometry. Results Percentages of T lymphocytes and NK cells in peripheral-blood mononuclear cells did not vary with age. The expression level of HLA class I on peripheral T lymphocytes and NK cells was not affected by age or gender, but was significantly down-regulated in Lijiadian villagers （P 〈0.05）, with the low-risk group, there was a significant reduction of cells （P 〈0.05） in the high-risk group. especially on the surface of NK cells （P 〈0.01）. Compared HLA class I on peripheral T lymphocytes （P 〈0.05） and NK Conclusions HLA class I on peripheral T lymphocytes and NK cells may be involved in tumorigenesis and development of gastrointestinal tumor, and understanding their changes in expression may provide new insights into the mechanism of tumor immunity.