GENE-TRANSFER BY ADENOVIRUS IN SMOOTH-MUSCLE CELLS

We report adenovirus-mediated gene transfer into airway smooth muscle cells in cultured cells and organ-cultured tracheal segments. Incubati on of cultured rat tracheal myocytes with virus (5 x 10(8) pfu/ml) for 6 h resulted in beta-galactosidase expression in 94.8 +/- 2.5% of cel ls (n = 4). Following incubation of thin (less than 200 mu m diameter) equine trachealis muscle segments with virus in organ culture (5 x 10 (8)-5 x 10(10) pfu/ml) the average expression of the Lac Z gene was ap proximately 19 +/- 10% (n = 9). Expression was markedly improved, howe ver, in segments from neonatal rats (13-21 days). In two experiments i n which the mucosa and serosa were removed, nearly all cells expressed beta-galactosidase, whereas in a third experiment in which the tissue was not dissected, about 40% of cells were stained. Viral infection h ad no effect on tension development of strips following organ culture. In vitro gene transfer may provide a useful method to alter protein e xpression and examine the effect of this alteration on excitation/cont raction coupling in smooth muscle.