Transcription factors in spinal dorsal root ganglion in rats recurrently infected with respiratory syncytial virus / 中南大学学报(医学版)

ABSTRACT

Objective To elucidate intracellular transcription factor activation of C_7～T_5 dorsal root ganglia in rats recurrently infected with respiratory syncytial virus (RSV). Methods Eighty 1～2 weeks old Sprague-Dawley rats were randomly divided into 2 groups a control group and a RSV-infection group. The rats in the RSV-infection group were infected with 5 ×10~5 U/mL RSV once a week and the rats in the control group were treated with culture medium without RSV. Airway response was measured after 8 weeks. Lung tissue was submitted for HE staining and in situ hybridization. The C_7～T_5 dorsal root ganglia were obtained for the preliminary screening of the intracellular transcription factors by TranSignal~(TM) protein/DNA combo array. Nuclear protein of C_7～T_5 dorsal root ganglia were extracted and submitted to Western blot. Results Airway response in the RSV-infection group was higher than that in the control group (P＜0.05). HE staining showed inflammatory cell infiltration, and in situ hybridization demonstrated positive RSV RNA in the RSV-infection rat lung which was not present in the control group, thus validating the efficacy of our model. TranSignalTM protein/DNA combo array screening showed that 55 transcription factors increased by at least 2 folds in the C_7～T_5 DRG cells of the RSV-infection group. The transcription factors Smad and interferon regulatory factor (1 or 2) were the 2 most upregulated transcription factors identified by combo array screening (59 and 43 fold increase compared with the control, respectively). Western blot confirmed Smad(1/2/3) and IRF-1 upregulate while IRF-2 remained unchanged. Conclusion Respiratory syncytial virus infection results in airway hyperresponsiveness and transcription factor activation in C7～T5 spinal adorsal root ganglia in rats, which may contribute to airway nerve network dysfunction and airway hyperresponsiveness.