Connective tissue growth factor and pulmonary allograft fibrosis in rats / 中南大学学报(医学版)

ABSTRACT

OBJECTIVE@#To investigate the role of connective tissue growth factor (CTGF) in pulmonary allograft fibrosis in rats.@*METHODS@#The lungs of 20 Wistar rats were transplanted into 20 Sprague-Dawley(SD) rats. Ten allograft lungs were harvested 1 week postoperatively (acute rejection group,AR); the other 10 allografts were harvested 6 weeks postoperatively (chronic rejection group,CR); and ten normal Wistar rats served as a control group(normal lung, NL). Paraffin embedded sections of the harvested lung specimens were stained with hematoxylin and eosin (HE), Van Gieson (VG) for the examination of tissue morphology under the microscope. The scores of lung fibrosis were measured and the wet/dry ratio of the lung specimens was evaluated. The CTGF expression was determined by immunohistochemical method.@*RESULTS@#The wet/dry ratios of lung decreased gradually(AR group vs. control group 3.48+/-0.47 vs. 4.67+/-0.51, P<0.05; CR group vs. AR group 2.85+/-0.52 vs. 3.48+/-0.47, P<0.05). The transplanted lungs showed massive lymphocytic infiltration, interstitial fibrosis, destroyed alveolus architecture, obliterative bronchiolitis, and lung tissue consolidation. These pathological changes were more severe in the CR group than in the AR group, but there were no such changes in the control group (scores of pulmonary fibrosis NH, 0.00+/-0.00; AR, 0.98+/-0.47; CR, 2.35+/-0.52; AR vs. NH, P<0.01; CR vs. AR, P<0.01). CTGF was not expressed in the normal rat lungs (0.00+/-0.00); however, it was detected in the lung allograft after the operation. The CTGF expression in the CR group was significantly higher than that in the AR group (P<0.01).@*CONCLUSION@#The expression of CTGF protein is related to the transplanted pulmonary fibrosis,and is involved in the pathogenesis of transplanted pulmonary fibrosis.