Immune Regulation Effect Of Polysaccharopeptide On Human Peripheral Blood Lymphocytes In Vitro

Objective:To Study the immunomodulative effects of polysaccharopeptide (PSP) on healthy humans peripheral blood lymphocytes in vitro.Methods:Peripheral blood mononuclear cells (PBMCs) from healthy donors were obtained by leukapheresis followed by ficoll-density centrifugation. The isolated cells were plated on 24-well plates(1000μl per well)at a concentration of 1×106cells per milliliter in RPMI1640 supplemented with 10% fetal calf serum. The PBMCs were divided into three groups and were cultured for 72 hours in vitro.Flow cytometry was used to assess the percentages of human lymphocyte subsets. The expression of CD3+/HLA-DR+T cells and CD19+/CD69+ B cells were measured by Flow cytometry at 24,48 and 72 hours. The level of IgG in the supernatant was measured by enzymelinked immuno-sorbent assay (ELISA) at 24,48 and 72 hours.Results:After 72 hours of culture, percentage of CD4+ T cells in PBMC+PSP groups were increased significantly as compared with those in PBMC group(p<0.05).Moreover, the ratio of CD4+/CD8+ in PBMC+PSP groups were significantly increased compared with those in PBMC group(p<0.05) The expression of CD3+/HLA-DR+ of T lymphocytes and CD19+/CD69+ B cells at 24h,48h and 72h have statistical significance(p<0.05). The levels of IgG in PBMC+PSP groups were higher than those in PBMC group(p<0.05).Conclusion:The PSP can promote the activation of T and B lymphocytes.It was a immunopotentiating drug and could promote the cellular and humoral immune response of humans.