[Immunocompetence effects of polysaccharide of snakegourd root on human peripheral blood mononuclear cells in vitro]

To establish the method of promoting human peripheral blood mononuclear cell proliferation by polysaccharide of snakegourd root and identify the effects of polysaccharide of snakegourd root on lymphocyte proliferation, T lymphocyte subsets and the different levels of TNF-alpha and IL-6.

The polysaccharide of snakegourd root preparations were purified with dialysis and ethanol precipitation. The healthy human PBMC were used as the target cells for screening potency of the drugs. MTT colorimetry was established to examine the levels of lymphocyte proliferation on human PBMC by polysaccharide of snakegourd root in vitro. The percents of lymphocyte subsets (CD3+, CD4+, CD8+ T lymphocyte) and the different levels of TNF-a and IL-6 in PBMC were analysed by FCM and ELISA, respectively.

1.0-50.0 mmol x L(-1) of polysaccharides of snakegourd root showed the significant effects of promoting proliferation of human PBMC (P < 0.05). The percents of CD3+, CD4+, CD8+ T lymphocytes in PBMC treated with 5.0 and 10.0 mmol x L(-1) of polysaccharides of snakegourd root were significantly higher than those of the control group (P < 0.05). The levels of TNF-alpha and IL-6 were significantly higher than those of the control group after 1.0, 5.0, 10.0 mmol x L(-1) of polysaccharides of snakegourd root stimulation on the human PBMC at 8 hours (P < 0.05).

The significant effects on promoting lymphocyte proliferation and activation of the polysaccharide of snakegourd root are confirmed in this study. The percents of lymphocyte subsets are increased in different degrees by the polysaccharide of snakegourd root. The high levels of TNF-alpha and IL-6 are secreted after the polysaccharides of snakegourd root stimulation on the human PBMC, which lays a foundation for further elucidating the immunocompetence effects and mechanism of the polysaccharide of snakegourd root.