CYTOKINE PRODUCTION BY CULTURED HUMAN BRONCHIAL EPITHELIAL-CELLS INFECTED WITH A REPLICATION-DEFICIENT ADENOVIRAL GENE-TRANSFER VECTOR OR WILD-TYPE ADENOVIRUS TYPE-5

Exposure of animals to adenoviral gene transfer vectors has been assoc iated with respiratory tract inflammation. The pathogenesis of this in flammation is unclear. One hypothesis is that viral vectors directly i nduce production of inflammatory cytokines by host cells in, the airwa ys. We exposed cultured human lung cells to an adenovirus-5-based vect or containing the cytomegalovirus promoter and lacZ reporter gene (Ad. CMV.lacZ) and to wild-type adenovirus 5 (wtAd5) and measured subsequen t release of cytokines into cell culture supernatants. Inoculation of human bronchial epithelial (HBE) cells with Ad.CMV, lacZ at 10(1) to 1 0(4) plaque-forming units (pfu)/cell resulted in dose-related expressi on of lacZ by both X-gal staining and immunohistochemistry but did not increase release of interleukin (IL)-8 or IL-6 at 24, 48, or 96 h aft er inoculation. In the same cultures, tumor necrosis factor-alpha indu ced marked increases in release of both IL-8 and IL-6 at 24 and 48 h a fter stimulation. Similar data were observed in the BEAS-2B HBE cell l ine. HBE cells incubated with wtAd5 at doses of 10(1) to 10(3) pfu/cel l did not release increased amounts of IL-6 or IL-8 up to 48 h after i noculation, though wild-type respiratory syncytial virus (3 pfu/HBE ce ll) infection resulted in increases in both cytokines. Human alveolar macrophages obtained by bronchoalveolar lavage also showed no increase s in cytokine release after incubation with Ad.CMV.lacZ, though relati vely little gene transfer occurred in macrophages. These data do not s upport a role for direct induction of airway epithelial or alveolar ma crophage inflammatory cytokines in the pathogenesis of inflammation as sociated with exposure of airways to adenovirus or to adenoviral gene transfer vectors.