Glucan, a β1-3-polyglucosidic component of the cell wall of Saccharomyces cerevisiae, was evaluated for its ability to modify experimentally induced S. aureus septicemia in an immunosuppressed mouse model. AKR/J mice were injected with glucan (0.45 mg), cyclophosphamide (0.6 mg), isovolumetric saline (0.5 ml), or glucan (0.45 mg) and cyclophosphamide (0.6 mg) on days -10, -7, -4 and -1 prior to intravenous challenge with 1.0×109 S. aureus on day 0. In contrast to the significant (P<0.05) decrease in leukocytes observed in the cyclophosphamide-treated mice, the administration of glucan to cyclophosphamide-treated mice resulted in maintenance of the peripheral leukocyte counts. Furthermore, glucan, as a single pretreatment regimen, resulted in a median survival time of 12.5 days, as against only 7.5 days in the saline control group. A 1.4-day median survival was observed in mice pretreated with cyclophosphamide and subsequently challenged with S. aureus. However, when glucan and cyclophosphamide were administered together, a median survival time of 9.0 days was observed. Histopathologic examination revealed that glucan administration inhibited the renal necrosis observed in both normal and cyclophosphamide-treated mice following staphylococcal challenge. Glucan also produced a marked reduction of hepatic pathology in cyclophosphamide-treated mice following S. aureus challenge. These data denote that glucan administration is effective in altering morbidity and mortality due to systemic S. aureus disease in cyclophosphamide-treated mice. © 1979 Springer-Verlag.
