rhPDCD5 suppresses pro-inflammatory cytokine secretion and proliferation and induces apoptosis of activated lymphocytes from rats with collagen-induced arthritis / 南方医科大学学报

ABSTRACT

OBJECTIVE@#To investigate the effect of recombinant human PDCD5 (rhPDCD5) treatment in a rat model of bovine II collagen (CII)-induced arthritis (CIA) on inflammatory cytokine secretion, proliferation and apoptosis of activated lymphocytes and explore the mechanisms of rhPDCD5-induced immunosuppression on activated lymphocytes.@*METHODS@#Female Wistar rats were randomly divided into normal control group, CIA+ ovalbumin (OVA) group, CIA+ rhTNFR Fc group, and CIA+rhPDCD5 group. The rats in the latter 3 groups received intraperitoneal injections of OVA (14 mg/kg), rhTNFR Fc (3.5 mg/kg) or rhPDCD5 (14 mg/kg) from day 2 to day 26 following CII injection. On day 28, the spleens of the rats were harvested for preparing single cell suspensions of splenocytes, which were activated by CII (20μg/mL) or anti-CD3 (1μg/mL)+ anti-CD28 (2μg/mL) for 48 h and 72 h. The production of interferon-γ(IFN-γ) and interleukin-17A (IL-17A) by the activated lymphocytes was determined by ELISA of the culture supernatants. The proliferation and apoptosis of the activated lymphocytes were assessed using [H]-thymidine incorporation assay and flow cytometry, respectively.@*RESULTS@#Compared with those in CIA + OVA group, IFN-γand IL-17A secretions by the activated lymphocytes from rhPDCD5-treated CIA rats significantly decreased. RhPDCD5 treatment of the CIA rats obviously suppressed the proliferation and promoted apoptosis of the lymphocytes activated by CII or by anti-CD3 + anti-CD28.@*CONCLUSIONS@#rhPDCD5 reduces pro-inflammatory cytokine secretion, inhibits the proliferation and promotes activation-induced cell death of activated CD4 lymphocytes to produce immunosuppression in rat models of CIA.