Abstract: Objective　To investigate the clinical significance and expression of peripheral blood T lymphocyte subset CD3⁺,CD4⁺, CD8⁺and CD4⁺／CD8⁺ratio in patients with gastric cancer. Methods　Peripheral blood T lymphocyte subset CD3⁺, CD4⁺, CD8⁺and CD4⁺/CD8⁺ratio were determined by automatic blood cell analyzer in 40 patients with gastric cancer ［according to the clinical stages:Ⅰ-Ⅱ stage group (18 cases) and Ⅲ-Ⅳ stage group (22 cases)］ and 25 healthy subjects. Results　The peripheral blood T lymphocyte subset CD3⁺, CD4⁺ and CD4⁺／CD8⁺ratio in the gastric cancer group were 0.78%±0.35%，0.37%±0.21% and 0.61%±0.42%, respectively, which were significantly lower than those in the healthy control group (P<0.05). The T lymphocyte subset CD3⁺, CD4⁺ and CD4⁺／CD8⁺ratio in Ⅲ-Ⅳ stage group were 0.42%±0.27%，0.21%±0.17% and 0.29%±0.25%, which were significantly lower than those in Ⅰ-Ⅱ stage group（0.95%±0.35%，0.45%±0.19% and 0.76%±0.30%，P<0.05）. Conclusions　The determinations of T lymphocyte subset CD3⁺, CD4⁺, CD8⁺and CD4⁺／CD8⁺ratio in peripheral blood of patients with gastric cancer are helpful to study and assess the immune status of patients，but also provide a theoretical reference to improve tumor immune therapy .

Key words: T lymphocyte, CD3, CD4, CD8, Gastric cancer