Adenovirus-mediated overexpression of human transforming growth factor-beta 1 in rat cardiac fibroblasts, myocytes and smooth muscle cells

Transforming growth factor-beta 1 (TGF-beta 1) is known to regulate cardiac cell function and its overexpression in the heart is thought to contribute to the development of cardiac hypertrophy and fibrosis. We wished to develop a high efficiency gene transfer method that could be used both in vitro and in vivo and result in the overexpression of TGF-beta 1. For this purpose, we constructed a replication-deficient human adenovirus 5 vector encoding for human TGF-beta 1 and used for control purposes an adenovirus lacZ vector, The adenovirus 5 construct was capable of infecting neonatal rat cardiac myocytes, fibroblasts and VSMCs, Of the three cell types, cardiac myocytes appear more susceptible to infection by the adenovirus 5 construct as assessed through beta-galactosidase staining. Infection of cardiac fibroblasts, myocytes and VSMCs with the hTGF-beta 1 adenovirus leads to the expression of hTGF-beta 1 mRNA and enhanced levels of bioactive and total TGF-beta 1 protein. Infection with hTGF-beta 1 adenovirus also results in enhanced levels of collagen type III gene expression in VSMCs and fibroblasts whereas in cardiac myocytes it leads to increased levels for sarcomeric and beta-actin. Thus, this adenoviral Vector might be used for the exploration of in vivo effects of altered levels of cardiac TGF-beta 1. (C) 1996 Academic Press Limited