Abstract:

Objective To explore effects of p40 homodimer (p40) on T helper 17 cells in peripheral blood of patients with psoriasis. Methods Bone marrow cells of C57BL/6 mice were isolated and differentiated into bone marrow derived dendritic cells (BMDCs), and then BMDCs were cocultured with CD4+ T cells to differentiate in vitro into Th0 and Th17 cells. Fluorescence-activated cell sorting (FACS) was used to analyze IL-17 secretion and T cell proliferation in the presence or absence of  (p40)2. In addition, periphera blood mononuclear cells (PBMCs) from psoriasis patients and healthy donors were isolated and cultured with or without (p40)2. The IL-17 level in the culture supernatant was measured by ELISA. Results FACS analysis showed that (p40)2 had no obvious effect on Th0 cell proliferation whereas Th17 cell proliferation was significantly enhanced with high percentage of Th17 differentiation by adding (p40)2. In ELISA assay, the IL-17 concentration from cultures of PBMCs from psoriasis patients was significantly elevated upon adding (p40)2. In contrast, (p40)2 had little effect in augmenting the IL-17 level in healthy donors (P>0.05). Conclusion Cytokine (p40)2 plays a significant role in the pathogenesis of psoriasis by specifically promoting Th17 responses, which provides a possible explanation of the effectiveness of p40 monoclonal antibodies in treating psoriasis patients.

Key words: p40 homodimer, T helper 17 cell, psoriasis