RECOMBINANT VIRAL AND NON-VIRAL VECTORS CONTAINING THE HUMAN UROKINASE PLASMINOGEN ACTIVATOR GENE AND ITS UTILIZATION IN THE TREATMENT OF VARIOUS TYPES OF HEPATIC, RENAL, PULMONARY, PANCREATIC AND CARDIAC FIBROSIS AND HYPERTROPHIC SCARS

摘要

Hepatic cirrhosis is considered a severe health problem in Mexico, since it is the third mortality cause in working-age people and there is no 100% effective treatment. Cirrhosis is characterized by an exacerbated increase of collagen in liver parenchyma, replacing the hepatocytes and thus provoking liver failure. This is one of the reasons why we have used a gene therapy through specific delivery to cirrhotic livers of the gene of human urokinase plasminogen activator (huPA), which activates mechanisms that induce the degradation of excess cellular matrix and stimulate hepatocyte proliferation, obtaining thus a fast re-establishment of the liver function. In the instant invention, the modified human uPA gene was inserted in the adenoviral vector (pAd-ΔhuPA), because it is not secreted and does not provoke hypercoagulation or spontaneous internal bleedings. Moreover, data from the bio-distribution essay with an adenoviral vector with reporter gene β-gal have shown liver specificity as the target organ of the vector. Using ELISA, huPa protein was detected in liver homogenates (4500 pg/ml) in animals treated with pAd-ΔhuPA and was also intracellularly detected through immunochemistry in liver cuts (80% positive cells). huPa induced a dramatic fibrosis reduction (85%) on day 10 of vector administration, compared to control cirrhotic rats and 55% hepatocyte proliferation increase. Liver function tests (ALT, AST, alkaline phosphatase and bilirubin) dropped to nearly normal levels and hepatocyte proliferation was observed. Because of the two beneficial event cascades, gene therapy with modified huPA can be developed as a definite potential treatment for patients with liver cirrhosis.