Bisorbicillinol inhibits Lyn tyrosine kinase for allergic response on RBL-2H3 cells

Bisorbicillinol, which is isolated from Trichoderma sp. USF2690, is an inhibitor of beta-hexosaminidase release and tumor necrosis factor (TNF)-alpha, and Interleukin (IL)-4 secretion from rat basophilic leukemia (RBL-2H3) cells, with IC50 values of 2.8 mu M, 2.9 mu M and 2.8 mu M respectively. We showed that the inhibitory mechanism of beta-hexosaminidase release and TNF-alpha secretion involved inhibition of Lyn, a tyrosine kinase. The inhibitory activities of bisorbicillinol indicate that this compound is a new candidate anti-allergic agent.