Compositional characterization and immunomodulatory efficacy of konjac-derived manno-oligosaccharides in cyclophosphamide-induced immunosuppressed mice

Immunosuppression induced by diseases or pharmacological interventions severely impacts host health. While several dietary oligosaccharides have shown potential for alleviating immunosuppressive conditions, the biological role of manno-oligosaccharides (MOS) remains poorly characterized. This study investigated the immunomodulatory potential of MOS in cyclophosphamide-induced immunosuppressed BALB/c mice. The mice received MOS daily via oral gavage at 300 and 1200 mg/kg body weight for 28 days. Low-dose MOS enhanced serum hemolysin levels, antibody-forming capacity of splenocytes, and natural killer cell activity. High-dose MOS not only enhanced these parameters but also increased spleen index, macrophage phagocytic capacity, splenic lymphocyte proliferation, and levels of certain immunoglobulins and cytokines. MOS treatment also increased colonic tight junction protein levels, altered gut microbial diversity, and enriched bacterial taxa associated with butyric acid production and immune function. The findings underscore the potential of MOS as a promising dietary supplement to enhance immune function under immunosuppressive conditions.