Abstract: Zhu Teng, Jin Hongzhong Department of Dermatology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China Corresponding author: Jin Hongzhong, Email: jinhongzhong@263.net 【Abstract】 Objective To determine the of programmed cell death 1 receptor （PDCD1）, its ligands and downstream nuclear factor kappa B （NF-κB） in peripheral blood mononuclear cells （PBMC） of patients with generalized pustular psoriasis （GPP）. Methods The total RNA was extracted from 9 GPP patients and 10 healthy controls separately by using Trizol, and reverse transcription PCR （RT-PCR） was performed to determine the mRNA of PDCD1, programmed cell death 1 ligand 1 （PD-L1）, PD-L2 and NF-κB. Enzyme-linked immunosorbent assay （ELISA） was conducted to the serum levels of interleukin-27 （IL-27）, IL-22 and IL-4 in the peripheral blood of 23 GPP patients and 24 healthy controls. Results The mRNA of PDCD1 was significantly lower in the GPP group （3.13 ± 4.62） than in the healthy control group （23.70 ± 15.33, t = 3.40, P < 0.05）. However, the mRNA of PD-L1 and PD-L2 was significantly higher in the GPP group than in the healthy control group （PD-L1: ［5.70 ± 3.07］ × 10-4 vs. ［2.00 ± 1.98］ × 10-4, t = 2.96, P < 0.05; PD-L2: ［0.95 ± 0.71］ × 10-4 vs. ［0.16 ± 0.20］ × 10-4, t = 3.38, P < 0.05）. There was no significant difference in the mRNA of NF-κB between the GPP group and the healthy control group （P > 0.05）. The GPP group also showed significantly higher levels of IL-27, IL-22 and IL-4 compared with the healthy control group （all P < 0.001）. Conclusion PDCD1 and its ligands were abnormally expressed in the PBMC of patients with GPP, and may play an important role in the occurrence and development of GPP.

Key words: Psoriasis, Programmed cell death 1 receptor, Programmed cell death 1 ligand 2 protein, Antigens, CD274, NF-kappa B