Abstract: LI Xin-hua, AN Peng, LI Jun-qin, HOU Rui-xia, LIU Rui-feng, ZHAO Xin-cheng, YAN Xin, YANG Yuan-wen, YIN Guo-hua, ZHANG Kai-ming. Department of Dermatology, Taiyuan Central Hospital, Taiyuan 030009, China Corresponding authors: ZHANG Kai-ming, Email: zhangkaiming@sina.com; YIN Guo-hua, Email: yinguohua1999 @sina.com 【Abstract】 Objective To detect the expression of the Notch signaling pathway, and a downstream target gene of the pathway, Hes-1, in peripheral blood T cells of patients with psoriasis vulgaris. Methods Peripheral blood samples were collected from patients with psoriasis vulgaris and healthy human controls, followed by the isolation, culture, amplification and purification of peripheral blood T cells. Then, mRNA was extracted from the T cells and reversed to cDNA. Real time fluorescent quantitative PCR （RFQ-PCR） was performed to determine the expressions of Notch 1, Notch 2 and Hes-1 genes. Results The expression intensity of Notch 1, Notch 2 and Hes-1 genes in peripheral blood T cells from patients with psoriasis was 1.8391, 1.8423 and 2.5123 times that from the healthy human controls, respectively. Conclusions The overexpression of genes involved in the Notch signaling pathway may participate in the activation of peripheral blood T cells, which appears to be closely associated with the pathogenesis of psoriasis.