Adenoviral gene delivery can inactivate Kupffer cells: role of oxidants inNF-kappa B activation and cytokine production

Kupffer cells play a significant role in the pathogenesis of several Liver diseases; therefore, a potential therapeutic strategy would be to inactivat e the Kupffer cell with a gene-delivery system. Although recombinant adenov irus provides robust, transgene expression in parenchymal cells, whether ad enovirus transduces Kupffer cells is unclear. Thus, the purpose of this stu dy was to evaluate this possibility. In animals infected with adenovirus, K upffer cells were identified positively to express adenoviral transgenes by immunohisto-chemical techniques and Western blot analysis, indicating that Kupffer cells are transduced in vivo. Indeed, isolated Kupffer cells were transduced in vitro with recombinant adenovirus in a dose-dependent manner. Moreover, adenoviral transduction of Kupffer cells was blocked by inhibito rs of alphaV beta5 integrin, the co-receptor for adenovirus binding, suppor ting the hypothesis that adenovirus transduces Kupffer cells via an alphaV beta5 integrin-dependent mechanism, Indeed, it is shown here that Kupffer c ells express alphaV beta5 integrins, In a functional assay, infection of is olated Kupffer cells with adenovirus containing superoxide dismutase or I k appaB alpha super-repressor blunted LPS-induced nuclear transcription facto r kappa B (NF-kappaB) activation and tumor necrosis factor alpha (TNF-alpha ) production but not IL-10 production. Moreover, superoxide production was blocked by expression of superoxide dismutase, These data support the hypot hesis that LPS-induced NF-kappaB activation and TNF-alpha production in Kup ffer cells are oxidant-dependent. These findings suggest that Kupffer cell- targeted approaches may be a potential therapeutic strategy against many in flammatory diseases including early alcohol-induced liver injury.