RESUMO
Objective To investigate the expressions and significance of IL-22 and related cytokines (IL-23pl9 and IL-6) in sera and PBMCs of patients with psoriasis. Methods Sera and PBMCs were obtained from the venous blood samples from 58 patients with psoriasis vulgaris and 20 normal human controls. The PBMCs were subjected to culture for 5 hours followed by the collection of cells and culture supernatant. Then,quantitative real-time RT-PCR was used to examine the mRNA expressions of IL-22, IL-23pl9 and IL-6 in PBMCs, enzyme-linked immunosorbent assay (ELJSA) to detect the level of IL-22 protein in the sera and culture supernatant of PBMCs. Results In the patients with psoriasis and controls, the relative expression level in PBMCs was 4.48 ± 2.64 and 2.35 ± 0.91 respectively for IL-22 mRNA, 6.07 ± 4.09 and 2.61 ± 1.46 respectively for IL-23pl9 mRNA, 3.87 ± 1.49 and 1.48 ± 0.62 respectively for IL-6 mRNA; significant differences were observed between the two groups in all the above parameters (all P < 0.01). ELISA revealed that the level of IL-22 protein in the patients and controls was (86.23 ± 25.58) ng/L and (43.67 ± 14.82) ng/L respectively in the sera (P< 0.01), (119.11 ± 21.51) ng/L and (57.70 ± 13.17) ng/L respectively in the culture supernatant of PBMCs (P< 0.01). Conclusion There is an overexpression of IL-22 in the PBMCs and sera of patients with psoriasis, implying that IL-22 is involved in the pathogenesis of psoriasis.