ABSTRACT
To investigate the role of CD4+, CD25+, and CD127low regulatory T cells (Tregs) in multiple myeloma (MM). Methods:Levels of CD4+T cells and Tregs, as well as expression of CTLA-4 and apoptosis-related proteins, such as CD95, bcl-2, and Caspase3 of Tregs in peripheral blood of 30 patients with newly diagnosed cases, 27 patients under of complete remission (CR) from multiple myeloma patients, and 25 healthy adults were analyzed by flow cytometry. Results:The percentage of CD4+T cells in the untreated group was significantly lower than that of the control group (P<0.05). The percentage of Tregs in CD4+T cells in the untreated group was significantly higher than that of the CR group and control group (P<0.05), which in ISSⅢpatients of the untreated group was significantly higher than that in I/II(P<0.05). No significant difference of CD95 expression in Tregs was observed among the three groups. The expression of CTLA-4 in Tregs from the untreated group was significantly higher than that of the CR group (P<0.05) and control group (P<0.01), and so was in CR group than this in controls (P<0.05). The expression of bcl-2 in Tregs in the untreated group was significantly higher than that of the CR group (P<0.05) and control group (P<0.01), and so was in CR group than this in controls(P<0.05). The expression of Caspase3 in Tregs from the untreated group and CR group were all significantly lower than that of the control group (P<0.05). The percentage of Tregs in CD4+T cells in the untreated group was positively correlated with the proportion of bone marrow plasma cells (P<0.05). The percentage of Tregs in CD4+T cells from 15 MM patients who received bortezamib and dexamethasone (VD) chemotherapy was negatively correlated to the ratio of plasma cell reduction after the first VD chemotherapy (r=0.735, P<0.01). Conclusion:The level of Tregs in the peripheral blood of MM patients was positively correlated with tumor burden and progression of disease, but was negatively correlated with curative effect. The increased level of Tregs was associated with their strengthened anti-apoptosis function.