Serum-mediated stimulation and inhibition of neutrophil locomotion in sarcoidosis.

Chemotactic and chemokinetic activity was studied in sera from 57 patients with various stages of sarcoidosis. Reduced chemotactic activity was observed in 39% of the sera, mainly in sera from patients with parenchymal densities on chest radiographs. Increased chemokinetic activity was noted in more than one third of the fresh sarcoid sera. Asymptomatic patients showed higher chemokinetic activity in their sera than patients with symptoms. The presence of heat-stable chemokinetic inhibitors was suggested in one third of the cases. No relationship was found between these inhibitors and the inhibitors of neutrophil phagocytosis previously demonstrated in sarcoid sera. Although many of the findings show minor differences to those of normal sera, the liability in sarcoidosis to produce a variety of inhibitors directed against various functions of neutrophils would theoretically hamper the elimination of putative antigens. The presence of serum mediated stimulation and inhibition of neutrophil locomotion could be significant for the pathogenesis of the disease.