Metabolism of [14C]arachidonic acid by polymorphonuclear leukocytes in patients with psoriasis.

The formation of LTB4 and its omega-oxidation products 20-hydroxy- and 20-carboxy-LTB4 from exogenous [14C]arachidonic acid (AA) by neutrophils from 12 psoriatic patients and 10 healthy controls was investigated. Only a slight difference was detected in the mean amount of [14C]LTB4 produced. In contrast, the amounts of [14C]omega-oxidation products obtained from psoriatic PMN were 2.4-fold higher than the amounts from PMN of healthy controls. We conclude that in vitro, psoriatic PMN synthesize more LTB4 from exogenous AA than do PMN of healthy individuals and due to an efficient omega-oxidation system, the net release of LTB4 in both groups appears to be similar.