Down-regulation of human leukocyte antigens class I on peripheral T lymphocytes and NK cells from subjects in region of high-incidence gastrointestinal tumor.
- Author:
Zhi-Mian ZHANG
1
;
Ying-Jie LI
;
Xiao GUAN
;
Xiao-Yun YANG
;
Xi-Mei GAO
;
Xiao-Jing YANG
;
Li-Shui WANG
;
Xiong ZOU
Author Information
- Publication Type:Journal Article
- MeSH: Adult; Aged; Biomarkers, Tumor; analysis; Down-Regulation; Female; Gastrointestinal Neoplasms; immunology; Histocompatibility Antigens Class I; analysis; Humans; Killer Cells, Natural; immunology; Male; Middle Aged; T-Lymphocytes; immunology
- From: Chinese Medical Journal 2011;124(12):1813-1817
- CountryChina
- Language:English
-
Abstract:
BACKGROUNDMany 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.
METHODSA 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.
RESULTSPercentages 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), especially on the surface of NK cells (P < 0.01). Compared with the low-risk group, there was a significant reduction of HLA class I on peripheral T lymphocytes (P < 0.05) and NK cells (P < 0.05) in the high-risk group.
CONCLUSIONSHLA 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.