The effect of heat-inactivated BBMN68 on immune regulation and gut microbiota in immunosuppressed mice and exploration of its immunomodulation postbiotic functional components

作者：Limian Zhou, Huiyu Chen, Jingjing He, Hairan Ma, Pengjie Wang, Xiuying Wu, Guohong Wang, Yixuan Li, Hongliang Li, Baocai Xu, Ran Wang · 发表于：International Journal of Biological Macromolecules · 年份：2025 · DOI：10.1016/j.ijbiomac.2025.143758 · 被引用次数：5 · 研究领域：Gut microbiota and health、Probiotics and Fermented Foods、Viral gastroenteritis research and epidemiology

Previous research shown that live probiotics have immunomodulatory effects, however the effectiveness of heat-inactivated bacteria and their immune-related components require further study. This study evaluated the immunomodulatory effects of heat-inactivated BBMN68 in BALB/c mice and explored immunomodulatory postbiotic components in vitro. Cyclophosphamide-induced immunosuppressed mice were orally administered heat-inactivated BBMN68 for 15 days. Postbiotic components from heat-inactivated BBMN68 were utilized to stimulate RAW264.7 cells for 24 h. In vivo, heat-inactivated BBMN68 significantly mitigated body weight decline, improved immune organ index and enhanced hematopoietic function in immunosuppressed mice. Additionally, it promoted delayed-type hypersensitivity responses and increased serum hemolysin and immunoglobulin (IgA, IgG, and IgM) levels. Oral administration of heat-inactivated BBMN68 increased serum cytokine (IL-2, TNF-α, IFN-γ, IL-4 and IL-6), while reducing IL-1β and IL-10. It also boosted beneficial microbiota (Lachnospiraceae_NK4A136_group and Dubosiella) and reduced harmful microbiota (Clostridium_sensu_stricto_1, Faecalibaculum and Romboutsia) by altering the Firmicutes/Bacteroidetes ratio. Unlike live probiotics, heat-inactivated BBMN68 is safer and has stronger immunomodulatory effects than Levamisole. It uniquely modulated gut microbiota compared to other heat-inactivated probiotics. In vitro, peptidoglycan from heat-inactivated BBMN68 cell wall supp...