GDNF gene delivery via the p75(NTR) receptor rescues injured motor neurons.

The retrograde axonal transport mechanism of motor neurons has been exploited to deliver the gene encoding Glial cell line-derived neurotrophic factor (GDNF) into the central nervous system to provide trophic support following injury. A nonviral gene delivery system, consisting of a monoclonal antibody (MC192) that binds the neurotrophic receptor, p75(NTR), coupled to poly-L-lysine, was constructed and used to deliver the gene via a receptor-mediated mechanism. The MC192-poly-l-lysine/pGDNF complex was injected into the hind limb of newborn rats to allow gene expression within motor neurons prior to sciatic nerve transection.

Distribution and localization of pro-brain-derived neurotrophic factor-like immunoreactivity in the peripheral and central nervous system of the adult rat.

The precursors for neurotrophins are proteolytically cleaved to form biologically active mature molecules which activate their receptors p75NTR and trks. A recent study showed that the precursor for nerve growth factor (NGF) can bind to p75NTR with a high affinity and induces apoptosis of neurons in vitro. Mutation in Val66Met of brain-derived neurotrophic factor (BDNF) results in reduction in hippocampal function in learning and in the dysfunction of intracellular BDNF sorting and secretion.

Improved non-viral transfection of glial and adult neural stem cell lines and of primary astrocytes by combining agents with complementary modes of action.

Background: Rational design of gene vectors for therapeutic applications requires understanding of transfection mechanisms. In this study, multiple transfection assays revealed complementary mechanisms between two commonly used transfection agents. This finding was then exploited to produce improved transfection outcomes.

Hybrid tetanus toxin C fragment-diphtheria toxin translocation domain allows specific gene transfer into PC12 cells.

To study the mechanism by which genes can efficiently be transferred into specific cell types, we have constructed several novel, single-chain multicomponent proteins by recombining the nontoxic C fragment of tetanus toxin and the translocation domain of diphtheria toxin together with the DNA-binding fragment of GAL4 transcription factor, for transportation of plasmid DNA into neuronal cells. The C fragment of tetanus toxin provided neuronal selectivity, the translocation domain of diphtheria toxin permitted endosomal escape, and the GAL4 domain provided binding to DNA. To assess the cellular tasks of each component in gene transfer, different combinations of these fragments were produced by polymerase chain reaction, expressed in Escherichia coli, and purified under native conditions from the soluble proteins.