Distribution of circulating mononuclear cells in short-term PUVA-treated psoriatic patients and healthy subjects.

Peripheral blood mononuclear cells (PBMC), as defined by monoclonal antibodies (OKT3, OKT4, OKT8, OK 1, Leu 7, Leu 11b) were determined in 10 psoriatic patients and in 10 healthy subjects before and after administration of short-term PUVA therapy. A comparison of the mean baseline percentages of the two groups showed a statistically significant increase in Leu 7+ cells (p less than 0.001) as well as a slight increase in OKM1 and OKT8 positive cells in the psoriatic subjects. After 21 exposures, these subsets showed a reduction towards control values, while a significant increase in OKT3 and OKT4 positive cells (p less than 0.01) could be observed only in the control group. These results indicate that short-term PUVA therapy is associated with changes in PBMC subpopulations. This modification, however, does not necessarily imply a disturbance of immune system function, including natural killer activity.