Design and application of compartmentalized platforms for neurobiological research

Design And Application of Compartmentalized Platforms for Neurobiological Research Conventional culture systems remain inadequate for comprehensive understanding of injury and regeneration in peripheral neurons that extend axons over long distances and through varying extracellular microenvironments. Therefore, a highly tailorable in vitro system, that allows studying in different in vitro models that mimics axonal injury, regeneration and nerve transplants is required. This dissertation presents the development and application of novel compartmentalized in vitro cell culture platforms, where cell bodies are cultured on one side and axons are allowed to grow to the other side through microchannels that connect the two fluidically isolated compartments. These devices enable the manipulation of local environments and a more complete understanding of axonal degeneration and localized and site of action of toxic, neuroprotective, and neurotropic effects of agents in peripheral axons. First, regenerative effects of members of the glial cell-line derived nerve growth factor (GDNF) family of ligands (GFLs) were investigated in a microfluidic physical injury model and GDNF was most potent in promoting axon outgrowth after axotomy. Next, the first high throughput compartmentalized microfluidic platform (HTCMP) is developed, which is an innovative model for in vitro assays in drug screening, where distal axonal degeneration can be modeled by manipulating compartments independently. HTCMP is tested and implemented in drug screening, in order to identify therapeutic candidates for axonal protection from Paclitaxel induced peripheral neuropathy (PIPN). Flucinolone Acetonide (FA) is identified as a neuroprotective compound in vitro and validated in vivo that it demonstrates axonal protection from PIPN as well as relieving neuropathic pain. FA can be co- or pre administered before the injury to peripheral axons takes place, so that PIPN may be prevented. Finally, compartmentalized microfluidic platforms that mimics the isolated in vivo environment, are used in an in vitro model of stem cell replacement therapy for nerve injuries, and it is demonstrated that that the axons of mESC (mouse embryonic stem cell) derived motor neurons are myelinated by mESC derived oligodendrocytes. Keywords: compartmentalized microfluidic culture platform, chemotherapy induced peripheral neuropathy, Paclitaxel, GDNF, Flucinolone Acetonide, high throughput drug screening, myelination; embryonic stem cells (ESCs); mouse ESCs derived motor neurons; mouse ESCs derived oligodendrocytes.