We observed that TNF-α-treated HaCaTs-derived exosomes can accelerate the psoriasis process by delivering AGAP2-AS1 to promote CD4+ T cell differentiation towards Th1 and Th17 cells and secretion of more inflammatory factors such as IFN-γ and IL-17A, which affect the immune microenvironment. This evidence concerns the gene IL17A and psoriasis.