Expression of soluble sCD163 in serum of psoriatic patients is modulated by Goeckerman therapy.

BACKGROUND CD163 is the monocyte/macrophage receptor for haptoglobin-haemoglobin complexes. The aim of this study was to assess the kinetics in the expression of CD163 on monocytes and the concentration of soluble sCD163 in serum of psoriatic patients in order to examine the effect of Goeckerman therapy. METHODS sCD163 was measured in 71 patients before and after therapy, and in 57 healthy donors. A subgroup of 40 patients and 25 controls was used to assess the expression of membrane CD163. sCD163 was evaluated by ELISA. Flow cytometry method was used to determine the expression of membrane CD163 on monocytes, expressed as mean fluorescence index (MFI). RESULTS Before therapy, the serum level of sCD163 was significantly higher in our patients than in controls (P=0.0154). However, we observed a profound decrease in sCD163 in our patients after therapy (P=0.0037). Similar to sCD163, pre-treatment expression of CD163 on monocytes was significantly more enhanced in patients than that in controls (P=0.0078). There was a trend towards down-regulation of the expression after therapy, nonetheless, the change was not statistically significant compared to the values before therapy (P=0.8666). This was also confirmed by comparison with controls which displayed lower expression of CD163 than patients after therapy (P=0.0019). The disease activity, expressed as PASI score, was significantly decreased in our patients by GT (P=0.0001). CONCLUSIONS While sCD163 level in psoriatic patients was diminished after GT therapy, CD163 expression on monocytes was altered only to a minor extent.