A mushroom derived ‘carbohydrate‐fraction’ reinstates host‐immunity and protects from Leishmania donovani infection

The anti‐leishmanial effect of the ‘carbohydrate‐fraction’, isolated from an edible mushroom Astraeus hygrometricus, was evaluated against Leishmania donovani infection both in vitro and in vivo. Ahf‐Car induced the expression of inducible nitric oxide synthase 2 (iNOS2) and pro‐inflammatory cytokines like TNF‐α and IL‐12, with subsequent downregulation of the anti‐inflammatory cytokines as TGF‐β and IL‐10, in vitro and in vivo along with a remarkable increase in the expressions of IL‐6, IL‐1β, IFN‐γ and IRFs, IRF‐7 and IRF‐8 in vivo. Ahf‐Car also reduced the parasite burden in the spleen and liver dose‐dependently with a simultaneous proliferation of Ly6C+ cells in the bone marrow of Leishmania‐infected experimental animals. It also increased the monocyte population dose‐dependently and the expression of the myeloid transcription factor PU.1, in vivo, which presumably signifies the expansion of protective macrophages. Thus, Ahf‐Car might be a potent anti‐leishmanial lead with unique and effective adjuvant capacity. 1. Ahf‐Car is capable of inducing the pro‐inflammatory pathways of the anti‐leishmanial immune responses in the hosts. 2. Ahf‐Car‐induced increased proliferation of Ly6C+ cells in the bone marrow and elevated expressions of PU.1 in a pro‐inflammatory environment presumably signify the expansion of protective macrophages. 3. Ahf‐Car might be a potent anti‐leishmanial lead with unique and effective adjuvant capacity.