Immunological effects of β-glucan as a trained immunity-based adjuvant in vaccinated goats against anthrax.

Trained immunity-based adjuvants (TIbAs) have emerged as a promising strategy to enhance vaccine-induced protection through functional reprogramming of innate immune cells. The present study evaluated the adjuvant potential of β-glucan derived from Debaryomyces hansenii CBS8339 in a vaccine against anthrax in goats. Peripheral blood monocyte-like cells from vaccinated goats were assessed for effector and metabolic responses following ex vivo lipopolysaccharide stimulation. Co-administration of β-glucan and anthrax vaccine significantly enhanced crucial innate immune effector mechanisms, including phagocytic activity, nitric oxide production, and myeloperoxidase activity compared with control animals. Additionally, adjuvanted vaccination was associated with metabolic changes consistent with increased glycolytic activity (glucose consumption and lactate production). These findings suggest that β-glucan may function as a TIbA by enhancing innate immune responsiveness. Further studies are needed to elucidate the underlying molecular mechanisms and to determine the long-term implications of trained immunity-mediated adjuvanticity for improving vaccine performance.