Role of Soluble β(1-3),(1-6)-D-Glucan from Saccharomyces cerevisiae in the Murine P388 Ascites Tumor Model

Background: Therapeutic options for the treatment of malignant ascites are limited and could be broadened by immune-stimulatory drugs. Materials and Methods: Soluble beta(1-3),(1-6)-D-glucan from Saccharomyces cerevisiae was administered i.p. into DBA/2-mice bearing the P388 lymphoma either freshly inoculated or as an established ascites-tumor. Its effect on survival, ascites volume and production of cytokines was examined. Results: The early, but not the later, administration of beta-glucan showed a tendency to induce interleukin (IL)-12 in the ascites, whereas both treatment schedules demonstrated a clear tendency to reduce production of interferon-gamma in the abdominal fluid and had no notable impact on the level of tumor necrosis factor-alpha. Treatment with beta-glucan at either time-point showed no effect on the ascites volume and mean survival time. Conclusion: beta-(1-3), (1-6)-D-Glucan shows weak and differential modulation of immune-stimulatory and pro-inflammatory cytokines in tumor ascites dependent on the stage of tumor growth without affecting survival of the mice.