The objective of this study is to find the expression of IL-17A in the inflammatory infiltrating cells in the plaques as an important factors in the pathological progression in moderate to severe psoriasis.

The material that was obtained from 50 patients with moderate and severe psoriasis was inspected by an indirect immunofluorescence assay to assess the composition of cell infiltrate and the type of IL-17A-producing cells in the foci of lesion. The markers of dendritic cells (CD11c), lymphocytes (CD3), neutrophilic granulocytes (Mpo), and mast cells (Trp) were used for the determination. The proliferative activity of basal keratinocytes (Ki-67), the co-expression of IL-17A, Mpo, and Trp and the expression of IL-17A, were also evaluated.

The results of the study suggested that a positive association was established between the count of neutrophilic granulocytes in the infiltrate, the number of neutrophils expressing IL-17A and the expression of IL-17A with the extent of the disease along with the severity of the patients condition.

Thus, the study concluded that neutrophilic granulocytes along with their expression of IL-17A play significant roles in the pathogenesis of psoriasis.

Source: Smolyannikova VA, Karamova AE, Nefedova MA. Rol IL-17A i neĭtrofilnykh granulotsitov v patogeneze psoriaza [Role of IL-17A and neutrophilic granulocytes in the pathogenesis of psoriasis]. Arkh Patol. 2020;82(1):30-37. doi:10.17116/patol20208201130