Genetic manipulation of the pancreas: cell and gene therapy approaches for type 1 diabetes

摘要: La diabetes de tipo 1 resulta la destruccion autoinmune las celulas s pancreaticas, que conduce a una falta en produccion insulina y consiguiente hiperglucemia. terapia sustitutiva con inyecciones subcutaneas permite los pacientes llevar un vida activa, sin embargo esta es imperfecta no evita aparicion graves complicaciones secundarias. El transplante pancreas o islotes pancreaticos se ha realizado exito algunos pacientes, escasez donantes impide pueda aplicar todos individuos diabeticos. Por ello, gran cantidad esfuerzos han centrado diferenciacion madre, embrionarias adultas, s. Las medula osea (BMC) poseen propiedades celula madre adulta ademas son faciles obtener, por ello propuesto como fuente alternativa para formacion nuevas factor crecimiento I (IGF-I) participa regeneracion muscular e incrementa atraccion BMC el musculo danado. Ademas, expresion IGF-I especificamente ratones diabeticos capaz regenerar masa Asi, primer objetivo este trabajo fue estudiar capacidad atraer diferenciar s, tanto sanos Con finalidad transplanto transgenicos expresaban proteina verde fluorescente (GFP) constitutivamente, IGF-I. Los resultados obtenidos demostraron ni sobreexpresion induccion mediante estreptozotocina fueron causa suficiente pancreaticas in vivo. Estos datos sugerian del endocrino observada era mediada BMC, indicando replicacion preexistentes bien partir precursores hematopoyeticos mecanismos actuarian IGF-I. La intentando curar estrategias genica, hasta momento conseguido ninguna efectiva. recuperacion completa paciente diabetico requeriria Una aproximacion conseguir manipulacion genetica vivo, expresar factores induzcan neogenesis contrarrestar respuesta inmune. Sin embargo, riesgo inducir pancreatitis al manipular elevado, escasos intentos modificar geneticamente organo fecha. aproximaciones transferencia genica vivo necesarias avanzar desarrollo diabetes. En hemos estudiado eficiencia diferentes vectores virales vias administracion transducir perros. lugar, observamos transducidas eficientemente adenovirus inyectados via sistemica cuales les habia cerrado circulacion hepatica. Este resultado obtenido adenovirales primera generacion tambien obtuvo cuando usamos ultima generacion, llamados gutless. Ademas adenovirales, estudio adenoasociados serotipo 8 (AAV8). demostro AAV8 conducto pancreatico mas efectiva estos endovenosa intraperitoneal. El perro presenta estructura lobular vascularizacion similar humano, constituye buen modelo ensayar pancreas. transferir genes animales sometidos clamp circulatorio vasos pancreaticos. Adenovirus gen marcador s-galactosidasa inyectaron vena pancreaticoduodenal mantuvo durante 10 minutos. Usando tecnica consiguio acinares, ductales evidencias dano pancreatico. Esta ensayo diabetico. Por consiguiente, metodologia descrita puede ser usada ya sea perros, biologia desarrollar terapeuticas mellitus otras enfermedades pancreaticas. ______________________________________________________________ Type is characterized by progressive destruction of pancreatic ?-cells, resulting insulin deficiency and hyperglycemia. Insulin replacement therapy allows diabetic patients to lead active lives, but this imperfect does not prevent development severe secondary complications. Transplantation tissue or islets has been performed successfully limited numbers patients. However, the shortage donors primary obstacle that prevents treatment from becoming more widespread. Therefore, many efforts have focused on differentiating embryonic adult stem cells into s-cells. Bone marrow (BMCs) are an important source easily procurable proposed as alternative Insulin-like growth factor-I participates skeletal muscle regeneration enhances recruitment BMCs at sites injury. In addition, expression s-cells transgenic mice regenerates s-cell mass. Therefore one objectives study was investigate whether could increase differentiation under steady-state conditions after STZ treatment. To end, s-actin/GFP donor were transplanted mice. Our experiments demonstrated overexpression STZ-induced damage sufficient recruit differentiate GFP-labelled indicating these did contribute endocrine observed These data suggest replication pre-existing and/or non-BMC precursors most likely mechanism for IGF-I-mediated regeneration. Diabetes long targeted, yet unsuccessfully, being curable with gene therapy. Recovery type requires regeneration. One approach do so genetically engineering express factors induce counteract immune response. difficult manipulate serious concern, which made effective transfer organ elusive. Thus, new approaches delivery required. we examined different viral vectors routes administration rodents also large animals, determine efficient method deliver exogenous First, efficiently transduced s-galactosidase systemic injection adenoviral clamped hepatic circulation. This true both first generation well helper-dependent vectors. addition adenoviruses, compared ability AAV transduce intravascular, intraperitoneal intraductal delivery, last route administration. Like human pancreas, canine compact, vascularization structure. It therefore suitable model assess strategies. Here dogs circulation clamped. Adenoviruses carrying (s-gal) injected pancreatic-duodenal vein released min later. showed s-gal-positive throughout evidence damage. s-gal expressed mainly acinar cells, ducts islets. exocrine dog found be healthy dogs. Thus, methodology described herein may used interest murine islet biology develop other disorders.