Combinations of gene therapy, tissue transplantation and pharmacotherapeutic techniques in visual system repair

[Truncated abstract] Neurons in the adult mammalian brain and spinal cord have a poor ability of self repair following injury. Damage to the central nervous system (CNS) therefore results in irreversible functional deficits and new therapeutic methods need to be developed that enhance the survival and the regrowth of damaged nerve fibres. This thesis reveals the complexity of neuronal repair, but also presents data on novel combinatory CNS treatments that may lead to new improved clinical therapeutic strategies. The mammalian visual system is extensively used for studies on the basic cellular and molecular mechanisms involved in CNS injuries. In the retina, only retinal ganglion cells (RGCs) project axons to the brain which makes it an ideal system to study survival and regenerative responses following axonal damage to centrally derived neurons. The extent of RGC survival can be quantified by immunofluorescence, and by transplanting a peripheral nerve onto the cut optic nerve (PN-ON graft) the animal model also allows assessment of RGC regeneration abilities. Using this model, survival and regenerative factors can be determined and various new treatments can be quantitatively compared. Furthermore, several clinical trials have recently begun in attempts to treat human inherited or acquired eye diseases by using recombinant adeno-associated viral (rAAV) vectors to deliver protective or missing genes to retinal cells. Hence, it is also of great clinical ophthalmological value to study neuroprotection and repair in experimental visual system models. New vector systems are being developed and it is important to find improved ways of using this promising gene therapy strategy to treat blindness. In the first part of this thesis, seven recombinant (r)AAV vector variants were studied and their efficiency and specificity to deliver genes to retinal cells were evaluated.