Expression of programmed death-1, IL-22 and CRP in the peripheral blood mononuclear cells (PBMCs) of patients with psoriasis

Objective: To investigate the expressions and significance of Programmed death-1 (PD-1), IL-22 and CRP in PBMCs of patients with psoriasis. Methods: Sera and PBMCs were obtained from the venous blood samples from 52 patients with psoriasis vulgaris and 30 normal human controls. Reverse transcription- realtime quantitative polymerase chain reaction (FQ-RT-PCR) was used to examine PD-1 mRNA expression in peripheral blood monocytes. Flow cytometry (FCM) was used to detect PD-1 expression rate after activation. Automatic immune analysis machine was used to detect serum CRP level. The levels of IL-22 in culture supernatant of PBMCs were assayed by ELISA. The levels of CRP were assayed by automatic immune analysis machine. Results: (1)In the patients with psoriasis and controls, the relative expression level of PD-1 mRNA in PBMCs was 10.51±3.20 and 7.18±2.44 respectively (P<0.01). (2)After activation, the percentage of PD-1 on T cell was 5.06±3.31 and 7.99±4.09 respectively (P<0.01). (3)ELISA revealed that the level of IL-22 protein in the patients and controls was (124.02±24.44) ng/L and (58.29±20.35) ng/L respectively (P<0.01). (4)Serum CRP was (4.53±2.49) mg/dL and (0.34±0.17) mg/dL respectively (P<0.01). Conclusion: The costimulating factor PD-1 plays a negative role on T cell responses, it maybe correlated to the pathogenesis of psoriasis.