Adenovirus-mediated gene expression in isolated rat pancreatic acini and individual pancreatic acinar cells

In this study we have examined the feasibility of using replication-deficient recombinant adenoviral vectors to transfer and express genes in pancreatic acinar cells in vitro. We infected primary cultures of both isolated pancreatic acini and individual acinar cells with a recombinant adenovirus containing the coding sequence for β-galactosidase. Our data demonstrate that recombinant adenoviruses readily infect pancreatic acinar cells in vitro. Close to 100% infection and maximal β-galactosidase expression were obtained, when acini or acinar cells were infected with 5 x 106 or 106 plaque-forming units (pfu) of virus per millitre of acini or acinar cell suspension, respectively. Examination of the time-course of β-galactosidase expression showed that there was a lag of approximately 6 h before β-galactosidase levels increased. Thereafter β-galactosidase expression increased rapidly. By 20 h post-infection β-galactosidase activity had increased from undetectable levels to 2.5-3.0 units/mg of cellular protein. Acini/acinar cells maintained a robust secretory response after adenoviral infection. The cholecystokinin-octapeptide (CCK8) dose/response curves for amylase secretion for acini and acinar cells infected with 5 x 105 and 1 x 105 pfu/ml of virus, respectively, were biphasic, with maximal amylase secretion being stimulated by 1 nM CCK8. In addition, the dose/response curves were identical to those obtained from control, sham-infected, acini/acinar cells. Our findings indicate that replication-deficient recombinant adenoviral vectors will be excellent tools to transfer and express genes in isolated pancreatic acini or acinar cells.