ABSTRACT
Objective To investigate the effect of CD40siRNA on the pathologic changes and T helper lymphocyte (Th)-17 cells of myocardium and IL-17,IL-23 of serum in rats with experimental autoimmune myocarditis (EAM).Methods Forty 6-8 week old healthy male Lewis rats with body weight of 185-210 g were divided into EAM group,CD40siRNA group,siRNA group,and normal control group randomly,with 10 rats in each group.The rats in EAM group,CD40siRNA group and siRNA group were induced by immunization with cardiac C protein and completed Freund adjuvant in double foot pads.The rats in normal control group were injected with PBS buffer in double foot pads.On the 8th day after immunization,the rats in CD40siRNA group were injected with CD40 siRNA expression vector,and the rats in siRNA group were injected with siRNA expression vector.The rats were sacrificed on day 21 after inoculation.The histopathologic changes were observed by light microscope and the myocardial histopathology scores were calculated.The expression of RORC mRNA of myocardium was detected by real-time quantitative polymerase chain reaction (RTPCR).Enzyme linked immunoabsorption assay was used to determine the serum level of IL-17 and IL-23.Results Compared with EAM group,the myocardial histopathology score(2.34 ±0.60 vs 3.40 ±0.35,P ＜0.05),the expression ofRORC mRNA(2.13 ±0.28 vs 2.93 ±0.36,P ＜0.05) and the serum level of IL-17 (114.38 ± 8.29 vs 148.70 ± 5.04,P ＜ 0.05) and IL-23 (107.00 ± 7.69 vs 136.98 ± 23.16,P ＜ 0.05) were significantly lower in CD40 siRNA group.Conclusions It is suggested that CD40 siRNA expression vector might reduce myocardial injury by inhibiting Th-17 activation and down-regulating the expression of IL-17 and IL-23.
ABSTRACT
Objective To construct the RNA interference (RNAi) vector targeting the CD40 gene in rats.Methods Effective target sequences that target at CD40 gene were designed,then the oligonucleotide sequences after annealing of the complementary strands were synthetized,the DNA fragments were connected to the GV118 vectors by double digestion with HpaI and XhoI,and the lentiviral vectors which expressed short hairpin RNA were constructed.The lentiviral vectors were identified by PCR and DNA sequencing.Western blot was employed to sort the best interfering targets exogenously,and lentiviral packaging as well as assaying viral titer were also accomplished.Results CD40 siRNA was successfully inserted into the lentiviral vectors and the lentiviral vector was packaged into 293T cells.The determination of virus titer was 2.0 × 1012 TU/L.Conclusions The RNA interference lentiviral vector targeting the CD40 gene in rats was constructed successfully,which will provide the foundation for further exploring the pathogenesis of viral myocarditis and novel therapies in future.