Circulating T Lymphocyte Subsets, Costimulatory Molecules And Tregs In Multiple Myeloma

Objective:To investigate the level of circulating T lymphocyte subsets,the expression of costimulatory molecules on lymphocytes and regulatory T cells(Tregs) and to explore, T-Lymphocyte Immune State and their clinical significance in patients with multiple myeloma(MM).Methods:T lymphocyte subsets,CD28 positive T lymphocyte subsets,costimulatory molecules(CD80 and CD86) on lymphocytes and Tregs in peripheral blood of 38 patients with MM and 20 healthy doners were measured by the flow cytometry.Serumβ₂-MG, albumin and LDH in patients with MM were measured using transmission turbidimetry, bromocresol green method and rate method respectively.Results:(1) Compared to normal control group,the proportion of circulating CD8⁺T cells in patients with MM was higher,while the proportion of CD4⁺T cells,CD4/CD8 ratio and the proportion of CD4⁺CD28⁺ cells were lower.The expressions of CD80 and CD86 on circulating lymphocytes and the proportion of CD4⁺CD25^+/highTregs and CD8⁺CD28^-Tregs were higher.(2) When compared among clinical stages and control group,the higher proportion of CD8⁺T cells,the lower proportion of CD4⁺T cells,CD4/CD8 ratio,CD4⁺CD28⁺cells and CD8⁺CD28⁺ cells mainly existed in stageâ…¢group and the proportions of CD4⁺CD28⁺ and CD8⁺CD28⁺ cells in stageâ…¢group were lower than those in stageâ… ,â…¡and control group. The expressions of CD80 in stageâ… andâ…¡group and CD86 in all stages were higher than those in control group,however,there were no diferences when compared among clinical stages.The proportions of CD4⁺CD25^+/highTregs and CD8⁺CD28^-Tregs increased with clinical stage,and the proportion of CD4⁺CD25^high Tregs was significantly higher in stageâ…¢group than that in stageâ… group.The higher CD8⁺CD28^-Tregs proportion had statistical significance when compared among clinical stages.(3) When compared among different disease conditions and control group,the higher proportion of CD8⁺T cells,the lower proportion of CD4⁺T cells,CD4/CD8 ratio, CD4⁺CD28⁺ cells and CD8⁺CD28⁺ cells mainly existed in active MM.The proportions of CD4⁺CD28⁺ and CD8⁺CD28⁺ cells in active MM were lower than those in stable MM and control group.The expressions of CD80 and CD86 in all stages were higher than those in control group,and the CD80 expression was lower in active MM than that in stable MM. The proportion of CD8⁺CD28^- Tregs was higher in active MM than those in stable MM and control group.(4)The proportion of CD4⁺CD28⁺cells was negatively correlated with the level of serumβ2-MG.in MM.The proportion of CD4⁺CD28⁺cells,CD8⁺CD28⁺cells and CD4⁺CD25^high Tregs had positive,positive and negative correlation with the level of serum albumin respectively.Conclusion:MM patients had a disorder of circulating T lymphocyte subsets expressing low level of CD28 molecules,higher expression of costimulatory molecules on lymphocytes and higher level of Tregs.These results may have implication for immunotherapy of MM and were associated with clinical stages,disease progression and prognosis of MM to some extent.