Abstract:

Objective To investigate the mRNA expressions of IFN-gamma receptor and TNF-alpha receptor in peripheral blood mononuclear cells （PBMCs） of patients with psoriasis vulgaris and their role in the pathogenesis of psoriasis. Methods Fifty patients with psoriasis vulgaris （37 cases of active psoriasis and 13 cases of stable psoriasis） and 24 healthy human controls were included in this study. PBMCs were isolated from blood samples obtained from all patients and controls. The mRNA expressions of IFN-gamma receptor and TNF-alpha receptor in PBMCs were detected by RT-PCR. The disease severity in patients was evaluated by psoriasis area and severity index （PASI）. Results The mRNA expressions of IFN-gamma receptor and TNF-alpha receptor were observed in the PBMCs of all subjects. The mRNA expression levels of IFN-gamma receptor were 0.72 ± 0.17 in healthy controls, 1.11 ± 0.55 in all patients with psoriasis, 1.13 ± 0.57 in patients with active psoriasis and 1.03 ± 0.52 in patients with stable psoriasis, respectively. A significant increase was observed in the expression levels of IFN-gamma receptor mRNA in all psoriatic patients and in patients with active psoriasis compared with those in healthy controls （both P < 0.05）, but there was no significant difference between the healthy controls and patients with stable psoriasis （P > 0.05）. The expression levels of TNF-alpha receptor mRNA were 2.05 ± 1.34 in healthy controls, 2.70 ± 3.80 in all psoriatic patients, 2.90 ± 4.40 in patients with active psoriasis, 2.14 ± 1.05 in patients with stable psoriasis, respectively; there was no significant difference between psoriatic patients and healthy controls （P > 0.05）. However, no correlation was found between the mRNA expression of IFN-gamma receptor, that of TNF-alpha receptor, and disease severity in psoriatic patients. Conclusions The mRNA expression of IFN-gamma receptor in PBMCs is up-regulated in patients with psoriasis vulgaris, which is unrelated to the activity of psoriasis.