Analysis of the potential long-lasting effects of probiotic Debaryomyces hansenii CBS 8339 on trained immunity in newborn goats.

Trained immunity has been described as the memory capacity of the innate immune system. Several microbial components have been shown to induce trained immunity. Research on the potential of probiotics to trigger these effects has been limited to a few in vitro studies but remains completely unknown in vivo. Components from the probiotic Debaryomyces hansenii CBS 8339 (Dh) have been shown to induce innate immune memory in goat kids and calves. In the present study, stimulating innate immune cells from newborn goats with probiotic Dh increased respiratory burst activity and nitric oxide production, while cell phagocytosis was unaffected. Glucose uptake was enhanced in goat's cells stimulated with Dh, but lactate production was decreased. In newborn goats, after the training scheme (via oral probiotic administration), cell phagocytosis, nitric oxide production and glycolysis - through the upregulation of AKT and HIF1A gene expression, glucose consumption and lactate production- were enhanced. The expression of IL1B gene was similar between the D. hansenii and control groups. Moreover, the potential long-lasting effects were assessed 30 days after initiation of the training scheme. Cell phagocytosis, respiratory burst and myeloperoxidase activity were enhanced, while glycolytic parameters remained unaffected. Altogether, the results of the present study suggest that the immune training scheme may induce trained immunity by the probiotic D. hansenii in newborn goats. However, our findings were not conclusive regarding the long-lasting (one-month) effects of trained immunity by probiotics.