Blood polymorphonuclear behavior in patients with ankylosing spondylitis.

The oxidative metabolism and chemotaxis of polymorphonuclear leukocytes (PMNs) collected from patients with ankylosing spondylitis and healthy subjects were studied in parallel. The responses to opsonized zymosan were significantly lowered considering oxygen consumption and release of superoxide anions, whereas no modification of these parameters to phorbol myristate acetate and calcium ionophore (A 23187) stimulations were observed. A seric factor was not involved but the characterization of a specific intrinsic abnormality of the PMNs needs further investigations. PMN chemotaxis, assessed by two methods performed in parallel, remained unchanged.