Immunomodulatory potential of polysaccharides from Coriolus versicolor against intracellular bacteria Neisseria gonorrhoeae

BACKGROUND AND AIM: For many years, people use natural products from the plant and fungal to improve immune response against microorganism. This study aimed to investigate the immunomodulatory properties of polysaccharides (PS) from Coriolus versicolor in mice infected by intracellular bacteria Neisseria gonorrhoeae. MATERIALS AND METHODS: Thirty-six female BALB/C mice were divided into six groups: Normal control, negative control, positive control, P1 (PS before infection), P2 (PS after infection), and P3 (PS before and after infection). PS were administrated for 10 days. N. gonorrhoeae was infected twice with 2 weeks gap from the first to second exposure with a dose of 10(6) cells. 1 week after the end of treatment, level of oxidants, innate immune responses, and adaptive immune responses were measured. RESULTS: This study showed that PS administration could restore the number of leukocytes as normal but could not enhance the number of phagocytes and its activity. PS administration also showed immunosuppression activity by lowering nitric oxide levels in P2 and P3 groups (p<0.05). This result showed that PS prevent over-expression of pro-inflammatory cytokines by decreasing phagocytic activity. Contrast with innate immune response result; PS administration could significantly increase interferon-gamma level in P1, P2, and P3 groups (p<0.05). Level of antibodies was significantly increased in the P3 group (p<0.05). PS administration also showed an increased level of tumor necrosis factor-α, but the difference was not significant (p>0.05). CONCLUSION: PS enhance adaptive immunity due to the capability of N. gonorrhoeae that able to survive and replicate in phagocytes. Thus, PS from C. versicolor could be potentially be used as a natural immunomodulator against intracellular bacteria.