RESUMO
The immune response of liver transplant recipients was modulated via adenovirus-mediated transduction of the cold-preserved liver with sequences encoding CTLA4Ig. Transplanted allografts demonstrated rapid transient local expression and recombinant protein production shortly after revascularization, resulting in intact liver function, indefinite survival of the recipient, and the development of donor-specific unresponsiveness. Lymphocytic infiltration of the graft was mainly of the T helper 2 (Th2) subset and was not associated with injury to primary cellular targets of the alloimmune response. These findings demonstrate a successful outcome of a feasible and potentially clinically relevant system of gene delivery of sequences encoding proteins capable of inhibiting the alloimmune response.
Assuntos
Adenoviridae/genética , Antígenos de Diferenciação/genética , Sobrevivência de Enxerto , Imunoconjugados , Transplante de Fígado/métodos , Transplante Homólogo/imunologia , Abatacepte , Animais , Antígenos CD , Antígenos de Diferenciação/metabolismo , Aspartato Aminotransferases/metabolismo , Antígeno CTLA-4 , Criopreservação , Técnicas de Transferência de Genes , Fígado/fisiologia , Transplante de Fígado/imunologia , Perfusão , Ratos , Ratos Endogâmicos ACI , Ratos Endogâmicos BN , Ratos Endogâmicos Lew , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Transdução GenéticaRESUMO
Inherited and acquired disorders of the liver are attractive targets for gene therapy. Hepatic cells are susceptible targets for shuttle vectors because of a diversity of protein and viral receptors and accessibility of a selective afferent blood supply. Preservation of existing hepatic cell integrity and metabolic function is of paramount importance for successful whole animal gene therapy trials. In this report, we examine hepatic cell function and integrity following adenovirus-mediated reporter gene transfer to the liver in vivo. E1-deleted, replication-defective adenovectors encoding the LacZ gene driven by the human CMV promoter were delivered to the liver by isolated portal perfusion. The gene transfer rate, as determined by specific histochemical staining, approached 30% with recombinant protein detectable by Western blot throughout the course of study. Hepatic cell integrity as assessed by histology and hepatic enzyme profile (serum aspartate aminotransferase, gamma-glutamyl transpeptidase) demonstrated normal cellular architecture and no significant difference between transfected liver and controls. Hepatic synthetic and metabolic function, as determined by albumin levels, prothrombin time, and bilirubin, were similar between the two study groups. This study demonstrates that efficient adenovirus-mediated gene transfer and expression in the rat liver do not compromise hepatic cell metabolism and integrity.