In vitro myelination by oligodendrocyte precursor cells transfected with the neurotrophin‐3 gene

Abstract

Oligodendrocyte precursor cells require exogenous neurotrophin-3 (NT-3) for differentiation into oligodendrocytes. We transfected precursor cells with the gene for NT-3 and looked for changes in their development into myelin-forming cells. The expression of NT-3 in transfected cells was demonstrated by reverse transcription followed by PCR as well as by Northern blots. Direct synthesis of the neurotrophin product and its release to the culture supernatants were also shown by specific ELISA. Transfection converts precursor cells into actively dividing cells that can incorporate 3H-thymidine into DNA. In the absence of growth factors, a parallel increase in the survival of the transfected cultures was also demonstrated by the MTT test. The final demonstration of biological changes in transfected versus untreated cells was a 10-fold increase in myelin basic protein production observed in Western blots and the direct observation by phase-contrast and electron microscopy of myelin membranes in cocultures with hippocampal neurons. We discuss the future use of this transfected cells in regeneration and functional recovery in experimental models of multiple sclerosis.

Functional Recovery in Traumatic Spinal Cord Injury after Transplantation of Multineurotrophin-Expressing Glial-Restricted Precursor Cells

“…Oligodendrocytic differentiation of the grafted D15A-GRPs was twofold greater than that seen with EGFP-GRPs, consistent with in vitro oligodendrocyte differentiation data. Myelination by GRPs of cultured neurons was significantly increased by NT3 (Yan and Wood, 2000;Rubio et al, 2004). D15A most likely promotes remyelination by directly enhancing the differentiation and myelination capacity of endogenous and grafted GRPs.…”

Grafts of Brain-Derived Neurotrophic Factor and Neurotrophin 3-Transduced Primate Schwann Cells Lead to Functional Recovery of the Demyelinated Mouse Spinal Cord

“…In the spinal cord, these adult OPCs proliferate in response to demyelination (Carroll and Jennings, 1994;Keirstead et al, 1998;Redwine and Armstrong, 1998;Reynolds et al, 2001), and it is well documented that an array of growth factors, including BDNF and NT-3, increases their proliferation and survival in vitro (McMorris and McKinnon, 1996;Rubio et al, 2004). Previous studies based on ex vivo gene transfer (McTigue et al, 1998) or direct injection of NT-3 (Jean et al, 2003) showed that NT-3 promotes a fivefold increase in the number of proliferating OPCs after injury.…”

Neurotrophin-3 gene modified mesenchymal stem cells promote remyelination and functional recovery in the demyelinated spinal cord of rats

“…NT-3 induces OPC proliferation and survival in both in vitro and in vivo studies [12,14,15]. In vitro studies demonstrate that NT-3 promotes OPC maturation and myelination [16,17]. In experimental demyelination models, NT-3 was shown to promote remyelination [18] and functional recovery [19] by enhancing OPC proliferation and differentiation.…”