Role of leukotrienes revealed by targeted disruption of the 5-lipoxygenase gene

Targeted disruption of 5-lipoxygenase gene by homologous recombination in embryonic stem cells establishes the physiological importance of leukotrienes, a class of biological mediators of inflammation and anaphylaxis. The observed 5-lipoxygenase-deficient mice show resistance to the harmful effects of endotoxin shock induced by the platelet-activating factor and confirm that leukotrienes are vital to the pathophysiology of specific inflammatory states. Mast cells release chemotactic leukotrienes that facilitate neutrophil recruitment during early inflammatory insult.