Increased hydroxyl radical generation by normal polymorphonuclear leukocytes incubated in sera from patients with leukocytoclastic vasculitis.

The effect of sera from patients with untreated leukocytoclastic vasculitis was investigated on the generation of oxygen intermediates by normal polymorphonuclear leukocytes. Sera from untreated patients induced increased hydroxyl radical generation, which is one of the most potent oxidants capable of causing tissue damage. It is suggested that vascular injury may be mediated in part by enhanced production of hydroxyl radical by polymorphonuclear leukocytes. Circulating immune complexes in the sera of the patients are considered to be one of the factors responsible for enhanced generation of hydroxyl radical.