The Expression Of SOCS3 And SOCS5 In The TH1/TH2 Immune Imbalance Of RSV-infected Bronchial Epithelial Cell

Objective:Respiratory syncytial virus (RSV) is one of the most common viral pathogens causing severe lower respiratory tract infections in infants and young children,more and more epidemiology information show the close relationship between RSV-infected in infants and young and asthma in the old. The imbalance of Thl/Th2 is a key mechanism of airway inflammation and airway hyperresponsiveness,and whether or not the suppressor of cytokine signaling (SOCS)which have an effect up on Thl/Th2 cytokines balance is associated to asthma is still unknown.The experiment is to investigate the mechanism of immune imbalance of sustainable RSV-infected bronchial epithelial cell cultured with lymphocytes by observing the expression of Thl/Th2 cytokines as well as SOCS3 and SOCS5 ,and produce evidence of TH1/TH2 immune imbalance mechanism and the important role of SOCS for the better clinical treatment.Methods:RSV were inoculated on confluent Hela cell in culture flask, harvested and stored at-70℃as affection reached to 100%. Same protocol was performed to obtain the virus-free medium which were used as a negative control. The virulence of RSV was measured by TCID50 method.(1)To establish the sustainable RSV-infected model by serial passage of the bronchial epithelial cell which were infected with 0.0001 MOI RSV suspension and observe the expression of RSV protein in the model as well as the control group which were infected with non-RSV suspension by immunofluorescence.(2) To separate human peripheral blood lymphocytes acquired from health infants and young children aged from 1 month to 2 years in xiangya hospital and observe the expression of IFN-r and IL-4 in the supernatant of co-culture of above two group cells and T lymphocytes by enzyme-linked immunosorbent assay(ELASE).(3) To observe the expression of SOCS3 and SOCS5mRNA in lymphocytes by Real-time PCR and discuss the relationship with the TH immune imbalance.Results:(1) Immunofluorescence:There were flake fluorescence in the cytoplasm of bronchial epithelium cells infected by RSV.(2) ELISA: Compared with control group, the expression of IFN-r decreased significantly in RSV-infected group (t=-15.266,p<0.01) as well as IFN-r/IL-4 (t=-9.96,p<0.01),whereas the expression of IL-4 increased significantly in RSV-infected group (t=11.40,p<0.01).(3) Real-time PCR.:Compared with control group, the expression of SOCS3mRNA increased significantly in RSV-infected group (t=4.104,p<0.01),whereas the expression of SOCS5mRNA decreased significant in RSV-infected group (t=-7.417,p<0.01)Conclusion:(1) The sustainable RSV-infected bronchial epithelial cell could present typical high secretion of Th2.(2) RSV-infection could increse the expression of SOCS3mRNA in lymphocytes,in contrary,decrease the expression of SOCS5mRNA and may result in Th 1 / Th2 cytokines imbalance.