The Peripheral Blood Of Children With Acute Lymphoblastic Leukemia T-cell Surface Of Cd28, Ctla-4 Expression And Its Clinical Significance

Objective To investigate the expression of costimulatory molecules CD28 and CTLA-4 on peripheral blood T lymphocytes in patients with Acute Lymphoblastic Leukemia(ALL) and to explore their possible clinical significance.Methods The expression of costimulatory molecules CD28 and CTLA-4 on CD4+and CD8+T cells were measured in 21 patients(5 patients with high white blood cell) with newly diagnosed ALL and 20 healthy subjects as control group by flow cytometry(FCM).The expression of the peripheral blood T lymphocyte subsets CD4/CD8 was compared and its relationships with ALL was analyzed.Results The level of CD28 on CD4+T cells and on CD8+T cells of ALL were significantly decreased compared with normal controls(t=4.796,t=3.551 respectively, p<0.05);The levels of CTLA-4 on CD4+T cells and on CD8+T cells of ALL were significantly increased compared with normal controls(t=5.07,t=5.469 respectively, p<0.05). The level of CD28 on CD4+and CD8+T cell had no statistical significance between high and low white blood cell group(t=0.160, t=0.712 respectively, p>0.05). And the level of CTLA-4 also had no statistical significance(t=0.363, t=0.650 respectively,p>0.05). The level of CD4/CD8 was significantly decreased in ALL patients than in normal controls (t=3.477, p<0.05).Conclusion The expression of CD28 on peripheral blood T cell in ALL patients was decreased, however, the expression of CTLA-4 was up-regulated. The CD4+T cell and the ratio of CD4/CD8 were also decreased, which were suggested that the ability of immune activation in T cell was decreased, and the immune surveillance also descended, these may be one of the pathogenesis of ALL.