Gene therapy
-
Local gene transfer of the human Lim mineralization protein (LMP), a novel intracellular positive regulator of the osteoblast differentiation program, can induce efficient bone formation in rodents. To develop a clinically relevant gene therapy approach to facilitate bone healing, we have used primary dermal fibroblasts transduced ex vivo with Ad. LMP-3 and seeded on a hydroxyapatite/collagen matrix prior to autologous implantation. ⋯ LMP-3-modified dermal fibroblasts into a rat mandibular bone critical size defect model results in efficient healing, as determined by X-rays, histology and three-dimensional microcomputed tomography (3DmuCT). These results demonstrate the effectiveness of the non-secreted intracellular osteogenic factor LMP-3 in inducing bone formation in vivo. Moreover, the utilization of autologous dermal fibroblasts implanted on a biomaterial represents a promising approach for possible future clinical applications aimed at inducing new bone formation.
-
In this review, we summarize the work published over the last 2 years using genetic modifications of animals in the field of xenotransplantation. Genetic engineering of the donor has become a powerful tool in xenotransplantation, both for the inactivation of one particular porcine gene and for the addition of human genes with the goal of overcoming xenogeneic barriers. We summarize the work relative to the knockout of the alpha1,3-galactosyltransferase gene, followed by genetic engineering aimed at reducing the humoral and cellular immune response, complement activation and coagulation. Finally, we report on the genetic modification of pigs to reduce porcine endogenous retrovirus infection risk in the xenogeneic context.
-
Autologous or allogenic tumour cells have long been used in the fight against cancer as vaccines to awaken the patient's immune system. On the other hand, oncolytic viruses have emerged in recent years as powerful therapeutic tools for selectively killing tumour cells. ⋯ The present review focuses on how to overcome these limitations on oncolytic virus delivery, at least in part, through the use of tumour-derived or in vitro transformed carrier cells. On the basis of existing evidence, novel strategies are proposed for using such cell vehicles, alone or in combination, both as virus factories and as anticancer vaccines.
-
To dissect the molecular basis of the neuroimmune response associated with the genesis of inflammatory (nociceptive) pain, we constructed a herpes simplex virus-based gene transfer vector to express the antiinflammatory cytokine interleukin-10 (IL-10), and used it to examine the effect of IL-10 expression in activated microglial cells in vitro, and in inflammatory pain in vivo. IL-10 reduced the phosphorylation of p38 mitogen-activated protein kinase (MAPK) and decreased the expression of full-length membrane spanning tumor necrosis factor-alpha (mTNFalpha) following lipopolysaccharide stimulation of microglia in vitro. IL-10 also reduced intracellular cleavage of mTNFalpha and release of the soluble cleavage product sTNFalpha. ⋯ Local release of IL-10 achieved by gene transfer reduced the number of spontaneous flinches in the early and delayed phases of the formalin test of inflammatory pain. The effect of IL-10 on nocisponsive behavior correlated with a block in phosphorylation of p38 and reduced expression of 26 kDa mTNFalpha in spinal microglia. The results emphasize the key role played by membrane TNFalpha in the spinal neuroimmune response in pain caused by peripheral inflammation.
-
The ability to manipulate mitochondrial DNA (mtDNA) heteroplasmy would provide a powerful tool to treat mitochondrial diseases. Recent studies showed that mitochondria-targeted restriction endonucleases can modify mtDNA heteroplasmy in a predictable and efficient manner if it recognizes a single site in the mutant mtDNA. However, the applicability of such model is limited to mutations that create a novel cleavage site, not present in the wild-type mtDNA. ⋯ Scal recognizes five sites in the NZB mtDNA but only three in BALB mtDNA. Our results showed that changes in mtDNA heteroplasmy were obtained by the expression of mitochondria-targeted ScaI in both liver, after intravenous injection, and in skeletal muscle, after intramuscular injection. Although mtDNA depletion was an undesirable side effect, our data suggest that under a regulated expression system, mtDNA depletion could be minimized and restriction endonucleases recognizing multiple sites could have a potential for therapeutic use.