Increased respiratory burst activity of monocytes and polymorphonuclear leukocytes in psoriasis

We studied the respiratory burst activity of peripheral blood monocytes and polymorphonuclear leukocytes (PMN) in eleven patients with psoriasis and eleven healthy controls, using zymosan particles to activate the phagocytes in vitro. The activation of the phagocytes was measured in a luminol-enhanced chiluminescence (CL) assay. We found a significantly higher respiratory burst activity of both monocytes and PMN in patients with psoriasis compared with the control subjects. The percentages of monocytes in psoriatics did not differ from those of the controls. The higher amount of zymosan-induced CL activity generated in the patient group was unrelated to the age of the individual. Our data indicate increased metabolic reactivity of both monocytes and PMN in psoriasis.