ABSTRACT
Reactive oxygen species (ROS) production by phagocytes is an important mechanism to kill invading microorganisms. Neutrophils from individuals with chronic granulomatous disease (CGD) do not produce ROS, thereby rendering these individuals more susceptible to infection. CGD results from mutations in the genes encoding essential subunits of respiratory burst NADPH oxidase, the enzyme complex necessary for the production of these reactive molecules. The absence of phagocyte ROS results in recurrent fungal and bacterial infections and inflammatory granulomas, associated with significant morbidity and mortality. Currently, the curative treatment is the allogenic bone marrow transplant (BMT); nevertheless, this therapy has some disadvantages including the HLA incompatibility, the immunosupression due to the myeloablative conditions necessary for the transplant and the high risk to develop graft vs. host disease. As an alternative to BMT the ex vivo gene therapy in hematopoietic stem cells has been intensely studied. Although this option could be the most appropriate treatment, it can give rise to other kinds of adverse effects. The genetic features of CGD have made it a very attractive candidate to be cured with gene therapy. This review summarizes and discusses the current advances about gene therapy and its application to CGD.
El sistema nadph oxidasa de las células fagocíticas es un complejo enzimático encargado de producir anión superóxido durante la respuesta contra los microorganismos. Mutaciones en los genes que codifican para las proteínas de este sistema son responsables de la Enfermedad Granulomatosa Crónica (EGC) que es una inmunodeficiencia primaria caracterizada por la presencia de infecciones recurrentes debidas a un grupo específico de microorganismos, principalmente oportunistas. Actualmente el tratamiento para la mayoría de los pacientes con EGC está dirigido a la prevención o al control de los procesos infecciosos, pero no a la curación de la enfermedad. El tratamiento curativo consiste en el trasplante alogénico de médula ósea (TMO); sin embargo, este método enfrenta dificultades como la incompatibilidad de HLA, la inmunosupresión debida a las condiciones mieloablativas necesarias para el trasplante y el riesgo de desarrollar la enfermedad injerto contra hospedero. Como una alternativa al TMO, ha surgido la terapia génica ex vivo en células progenitoras hematopoyéticas. Las características genéticas de la EGC le han permitido convertirse en un modelo para el estudio de la terapia génica ex vivo. En este artículo se describen y analizan los resultados que hasta la fecha se han obtenido en el campo de la terapia génica aplicada a la EGC.
Subject(s)
Genetic Therapy , NADPH Oxidases , Granulomatous Disease, Chronic , Genetic VectorsABSTRACT
Through genetic recombination technique, the rat glial cell line-derived neurotrophic factor (rGDNF) cDNA was in-serted into polylinker site of retroviral vector pLXSN, to generate a recombinant plasmid pLXSN-GDNF as transfer vector. Therecombinant plasmid was verified with restriction analysis, PCR, dot blot hybridization and Southern blot hybridization. The re-sults showed that GDNF cDNA was cloned correctly into retroviral vector pLXSN, recombinant retroviral vector was construct-ed. It is concluded that the eukaryotic cell expression vector was constructed successfully for gene therapy of Parkinson's,Alzheimer's and other central nervous system diseases.
ABSTRACT
Murine tumor necrosis factor(mTNF)cDNA was inserted into the polylinker site of MNSM retroviral vector to create pMNSM-SV40-mTNF. Albumin enhancer/promoter (Alb e/p) sequence was used to replace SV40 early region promoter of pMNSM-SV40-mTNF vector to create pMNSM-Alb e/p-mTNF recombinant retroviral vector. The retroviral constructs were introduced into amphotropic retroviral packaging cells PA317. Production of the recombinant retroviruses was accomplished by the lipofectamine-mediated gene transfer procedure. The murine tumor cells were infected with the retroviruses in the presence of polybrene. Dot hybridization of total RNA from modified tumor cell with mTNF cDNA probe and mTNF bioassay demonstrated that transcription and expression of mTNF gene drived by Alb e/p were markedly high in the hepatoma cells which produced albumin, and inhibited in the non-hepatoma tumor cells. The hepatoma cells modified with mTNF gene lost its tumorgenicity and significantly inhibited the growth of the parental hepatoma in vivo. High-titer MNSM-Alb e/p-mTNF retroviruses or the high-titer retroviruses producing packaging cells, after intra-tumoral injection, specifcally inhibited the growth of the hepatoma, and significantly prolonged the survival period of the hepatoma-loaded mice. Biopsy and immunohistochemical assay of the hepatoma during in vivo gene therapy, showed the occurrence of extensive tumor necrosis, bleeding, and CD8+, CD25+, CD4+ lymphocytic infiltration and fibrosis.
ABSTRACT
To construct retroviral vector carrying human interleukin-3 c0mplementary DNA(HuIL-3 cDNA) under control of human a-fetoprotein gene enhancer core sequence and human SV4O pro-moter. Methods and Results: HuIL-3 cDNA was inserted into polylinker site of retroviral vector pMNSMto construct retr0viral vector pMNS-IL-3, in which the transcription of HuIL-3 cDNA was drived by SV40early region promoter. Human Q-fetoprotein gene enhancer core sequence was released from plasmidpGEM. 7Zf-AFPe and inserted into the polylinker site of pMNSM. Then human interleukin-3 cDNA wasinserted int0 p0lylinker site to construct retroviral vector pMNSA-IL-3, in which HuIL-3 cDNA transcrip-tion was drived by SV40 early region promoter and enhanced by human a-fetoprotein enhancer core se-quence- Conclusion: The vectors are of significance for hepatoma-specific gene therapy.