Eosinophils Express LTA4 Hydrolase and Synthesize LTB4: Important for Asthma Pathogenesis?

Peripheral blood eosinophils cultured in vitro produced LTB4 when unstimulated, and they released significantly elevated levels of LTB4 when stimulated with aspirin-lysine, PMA, and platelet-activating factor. The authors compare the levels of LTA4 hydrolase mRNA in blood eosinophils isolated from both patients with asthma and control subjects. Surprisingly, in vitro release of LTB4 in stimulated and unstimulated peripheral blood eosinophils was lower in those obtained from patients with asthma compared with healthy control subjects.