| Objective To investigate the expression of Programmed death-1/Programmed death-ligand 1/2(PD-1/PD-L1/2)in CD4~+T cells,CD8~+T cells,and myeloma plasma cells in bone marrow of multiple myeloma(MM)patients and their correlation with clinical features.Methods We collected 22 patients with newly diagnosed multiple myeloma(NDMM),24 patients with response multiple myeloma(RMM),21 patients with relapsed/refractory multiple myeloma(RRMM),and 18 cases of healthy controls from the department of hematology of the 940th Hospital of the PLA Joint Service Support Force from June 2019 to December 2020.To collect bone marrow sample and clinical data from them,and to observe the proportion of CD4~+T cells,CD8~+T cells,and myeloma plasma cells by flow cytometry,and to explore the relationship between the expressing of PD-1,PD-L1,and PD-L2 and clinical features.Results 1.The proportion of CD8~+T cells in the MM groups was significantly increased than that in the Control group,and the ratio of CD4~+/CD8~+in the MM groups was significantly decreased than that in the Control group(P<0.05);2.The proportion of PD-1~+CD4~+T cells in the MM groups was higher than those in the Control group,and the proportion of PD-L2~+CD4~+T cells in NDMM group and RMM group was increased than that in the Control group(P<0.05);There was no statistically significant difference in the levels of PD-L1~+CD4~+T cells between the MM group and the Control group(P>0.05);The proportion of PD-1~+CD8~+T cells and PD-L2~+CD8~+T cells in the RRMM and RMM groups were higher than those in the Control group(P<0.05);There was no statistically significant difference in the levels of PD-L1~+CD8~+T cells between the MM group and the Control group(P>0.05);3.There was no statistically significant difference in the levels of PD-1,PD-L1,and PD-L2 in myeloma plasma cells in the MM groups(P>0.05);4.There is a growing tendency in the proportion of PD-1 in CD4~+T cells in the NDMM group than that in the CD8~+T cells(P<0.05);The proportion of PD-L1 and PD-L2 in CD4~+T cells in Control,RRMM,and RMM groups were higher than those in CD8~+T cells(P<0.05);The proportion of PD-1 in CD4~+T cells of Control,RRMM,and RMM groups were increased than those in CD8~+T cells,the proportion of PD-L1 in CD4~+T cells in NDMM group were increased than that in CD8~+T cells,and the proportion of PD-L2 in CD4~+T cells of RRMM group was increased than that in CD8~+T cells(P>0.05);5.There was no statistically significant difference between the levels of PD-1 and PD-L1/2 and the gender,age,immune typing,DS stage and subtypes,ISS stage and m SMART3.0 stratification in the NDMM patients(P>0.05).Conclusions 1.The ratio of CD4~+/CD8~+in the MM patients are decreased than those in the Control group,suggesting that the MM patients suffering immune abnormality which may be related to the increased of CD8~+T cells,and correlate with the criterion of therapeutical effect;2.The immunosuppressive effect of PD-1/PD-L1/2 pathway in MM may be related to the interaction between T cell subsets with high expression of PD-1 and myeloma plasma cells with high expression of PD-L1 and PD-L2,among which CD4~+T cells may be the main immune cells of immunosuppression;3.The expression levels of PD-1,PD-L1,and PD-L2 in T cell subsets and myeloma plasma cells of NDMM patients are not correlated with the gender,age,immune typing,DS stage and subtypes,ISS stage and m SMART3.0 stratification. |
