Is chemotactic activity of polymorphonuclear leukocytes increased in psoriasis?

Chemotactic activity of PMNs of 44 patients with common psoriasis and 20 healthy individuals was studied by modified Boyden chamber assay and casein as a chemoattractant. The patients were classified according to the activity of the disease, extent of skin lesions, and duration of the disease and of the last relapse. There was a high statistically significant increase in chemotactic response of the PMNs of psoriatics as compared with controls. The increase in chemotactic activity correlated positively with the activity of the disease but not with the extent of skin lesions. Very low values in some patients with longlasting and/or extensive lesions could depend upon the presence of inhibitory factors in plasma. The possible explanation for divergent results obtained by other authors could be due to the fact that various clinical parameters were not taken into account.