Probiotic Debaryomyces hansenii CBS 8339 yeast enhanced immune responses in mice

This study aimed to examine the effect of Debaryomyces hansenii CBS 8339 on innate immune responses in mice. Thirty BALB/c mice were randomly treated with phosphate buffered saline (PBS) (control) and two D. hansenii (Dh) doses: Dh 106 CFU (colony forming units) and Dh 108 CFU daily for 15 days. Spleen, blood, and gut samples were taken on days 7 and 15. Mouse splenocytes were isolated and challenged with Escherichia coli. Immunological assays and immune-related gene expressions were performed. Serum was obtained from blood for total IgA and IgG antibody titer determination. Gut samples were taken for yeast colonization assessment. Phagocytosis, respiratory burst activity, and nitric oxide production in mice were mainly enhanced (p < 0.05) upon 7 days of D. hansenii intake at a concentration of 108 CFU before and after bacterial challenge. Moreover, oral D. hansenii in mice upregulated (p < 0.05) gene expression of pro-inflammatory cytokines (INF-gamma, IL-6 and IL-1 beta) before or after E. coli challenge on day 7 but downregulated (p < 0.05) on day 15. Furthermore, total serum IgG and IgA titers were higher (p < 0.05) in Dh 108 CFU at days 7 and 15, and only at day 7, respectively, than that in the other dose and control groups. Finally, D. hansenii was detected in the gut of mice that received the treatments, suggesting that yeast survived gastrointestinal transit. Altogether, a short period (7 days) of D. hansenii CBS 8339 oral delivery improved immune innate response on mice.

Automated summary

This study investigated the effect of Debaryomyces hansenii CBS 8339 on innate immune responses in mice. The results showed that oral delivery of D. hansenii for 7 days enhanced phagocytosis, respiratory burst activity, and nitric oxide production in mice before and after bacterial challenge. It also upregulated the expression of pro-inflammatory cytokines on day 7, but downregulated them on day 15. Furthermore, D. hansenii increased serum IgG and IgA titers in mice. Overall, short-term oral delivery of D. hansenii improved immune innate response in mice.