Macrophages in host defense against Histoplasma capsulatum.

Macrophages function in both innate and cell-mediated immunity in host defense against pathogenic fungi. They initially serve as a protected environment in which the primary fungal pathogen Histoplasma capsulatum multiplies and disseminates from the lung to other organs. Upon induction of cell-mediated immunity, cytokines activate macrophages to destroy the yeasts and thus remove them from the host.