In vitro anti-allergic activity of the fungal metabolite pyridovericin

► The work evaluated the in vitro anti-allergic activity of pyridovericin (pyr). ► Pyr inhibited FcεRI-dependent and -independent degranulation of RBL-2H3 mast cells. ► Pyr impaired antigen-stimulated secretion of interleukin-4. ► Inhibition of stimulated Ca2 + accounts for the mechanism of action of pyr. ► Pyr is a promising prototype for the development of new anti-allergic drugs.