1992 Volume 45 Issue 5 Pages 698-703
WF11605, a new antagonist of leukotriene B4 (LTB4) was isolated as a product of fungal strain F11605. The molecular formula of WF11605 was determined to be C38H60O11 WF11605 inhibited LTB4-induced chemotaxis of rabbit polymorphonuclear leukocytes (PMNLs) with an IC50 value of 1.7×10-7 M and blocked 3H-LTB4 binding to PMNL membranes at 5.6×10-6 M (IC50). WF11605 also inhibited LTB4-induced degranulation of rabbit PMNLs at 3.0×10-6M (IC50). However, WF11605 did not show any inhibitory effect on platelet activating factor (PAF)- and N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP)-induced degranulation at concentrations up to 10-4M. These results suggest that WF11605 is a specific antagonist of LTB4.
