In vivo gene transfer into the lung Application in lung transplantation and therapeutic potential of HGF

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In vivo gene transfer into the lungThe aims of this study are 1) to determine the effect of retransfection of HVJ liposome system and 2) to compare the distribution of gene expression in the transtracheal and transplanted approaches in the setting of lung transplantation. Methods: Plasmid DNA of β-galactosidase (β-gal) were co-encapsulated in liposomes with high mobility group 1 (HMG1) protein, and were introduced into lung tissues by HVJ-mediated membrane fusion. Two groups of SD rats received intratracheal instillation of 0.3 ml of HVJ liposome solution containing 30μg of β-gal gene once on Day 0 (Group Tb-1, n = 4) and 3 times on Day 0-2 (Group Tb-3, n = 4). In another group, (Group Tx n = 3) orthotopic left lung transplantation was performed All isografts were flushed with PBS solution of 20 ml and preserved for 4 hours. HVJ-liposome complex (1.0 ml) containing β-gal gene was added to the flushing solution just before harvesting. Respective controls received HVJ-liposome with empty … More gene cassettes in a corresponding fashion. Two days after administration of β-gal gene, the transfected lungs were fixed and stained with X-Gal. The gene expression and distribution in the lung tissue was quantified by counting the staining cells. Results: There were no gene expression in the control animals. Three repetitive administrations via airway increased the expression in alveolar or airway epithelial cells by 2- to 4 fold compared to the single administration, indicating that the repeated transfection using HVJ-liposome system did not result in reduction of gene transfer efficiency without any inflammatory reaction. Compared to the transtracheal approach, successful gene transfer into the pulmonary endothelial cells using flushing solution as well as moderate degree of transfection into the airway and alveolar cells.Therapeutic potential of HGFHepatocyte growth factor (HGF) was initially identified as a potent mitogen for mature hepatocytes. Recent extensive and diverse studies have demonstrated that HGF has "tropic" roles in regeneration and maintenance First, HGF is a growth factor which promotes cell recovery following damage such as that associated with ischemia and drug toxicity. Second, in an experimental model of fulminant hepatic failure, HGF abrogated Fas-induced hepatocyte damage by eliciting of anti-apoptotic effect. Increased level of anti-apoptic protein BAG-1 (Bcl-2 functional partner) was also found to be associated with increased expression of HGF receptor, which: prevents cell death. Third, HGF may have therapeutic potential by its antifibtotic effects for the liver-fibrosis/cirrhosis, chronic glomelurosclerosis and pulmonary fibrosis.We first investigated the possible role of HGF on compensatory lung growth in mice. The endogenous HGF level in plasma peaked with 2.5 fold increase at day 3 after pneynibectiny, prior to the peak of the PCNA index at day 5. The expression and protein level of HGF in the remaining lungs also increased during this period. The PNCA index was significantly higher at day 3 in the recombinant human (rH)-HGF-treated group and was significantly lower in the antibody (a)-HGF group than in the corresponding controls. These results suggest that the supplement of HGF may accelerate postoneumonectomy compensatory alveolar regeneration while neutralizing HGF may delay this process. Less