Background & objective: It is well known that the patients with B-Non-Hodgkin's Lymphoma (B-NHL) usually have a poor immune response. CD4(+)CD25(+)-Tregs is a new type of suppressor cell. It plays an important role in the tumor immune suppression. But its distribution and the mechanism of immune suppression in B-NHL are still unknown. The present study was designed to evaluate the proportion of Tregs in peripheral blood of the patients with B-NHL with or without chemotherapy to investigate the mechanism of immune suppression in B-NHL and the effect of chemotherapy on immune system and provide evidence for effective intervention in immune function.
Methods: The peripheral blood was collected from 39 patients with B-NHL before chemotherapy, 32 patients with B-NHL who achieved partial remission (PR) or complete remission (CR) after 4-6 cycles of chemotherapy, and 25 healthy people. The population of CD4(+), CD8(+), CD4(+)CD25(+), and CD4(+)CD25(+)CTLA4(+) T cells was evaluated by flow cytometry.
Results: The total number of lymphocyte, the proportion of CD4(+)T cells, and the ratio of CD4/CD8 in the group of B-NHL before chemotherapy was significant less than those of the healthy group (1.3+/-0.39 x 10(9) versus 2.1+/-0.41 x 10(9); 27.5%+/-4.1% versus 32.9%+/-5.8%; 0.9+/-0.21 versus 1.31+/-0.4), but the percentages of CD4(+)CD25(+)-Tregs and CD4(+)CD25(+)CTLA4(+)-T cells were significantly higher than those of the healthy donors (14.7%+/-3.1% versus 8.4%+/-2.5%; 7.4%+/-1.6% versus 5.1%+/-1.4%). In the group of chemotherapy, although the CD4/CD8 ratio (1.19+/-0.3) was almost near to that of the healthy group, the total number of lymphocytes (0.8+/-0.53 x10(9)) was less than those of the other two groups, and the proportions of CD4(+)CD25(+)-Tregs (20.3%+/-4.1%) and CD4(+)CD25(+)CTLA4(+)-T cells (11.5%+/-2.2%) were higher than those of the other two groups.
Conclusion: The population of CD4(+)CD25(+)-Tregs in peripheral blood of the patients with B-NHL with or without chemotherapy was significantly higher than those in healthy donors, which may be one of the important reasons of immunosuppression in B-NHL.