(28o) Optimization of Functionalized Hydrogels for iPSC-Derived Midbrain Dopaminergic Neuron Culture

Despite the high prevalence and burden of neurological disorders, there are only a small number of drugs approved for treatment, and they offer limited efficacy. In vitro models of the human central nervous system, especially those derived from human induced pluripotent stem cells (iPSCs), provide a unique opportunity to study mechanisms of neurodegenerative disease propagation, which can assist with the development of candidate therapeutics. To build more representative three-dimensional models of the human brain, our lab previously developed a peptide-functionalized gelatin hydrogel that enhances iPSC-derived glutaminergic neuron maturity and synaptic connectivity by mimicking bio-instructive cues that are relevant to neural development. Moving forward, we seek to utilize this hydrogel to develop models of specific brain regions afflicted by disease. We are specifically interested in Parkinson’s disease (PD), which is a hypokinetic neurodegenerative disorder pathologically characterized by loss of midbrain dopaminergic neurons (mDANs). Current gold standard animal models of PD do not mimic the natural progression of this disease and cannot be used for temporal investigations. Therefore, we are developing an in vitro model by iPSC-derived mDANs with our hydrogel to better capture the pathology of PD. We are optimizing the composition of conjugated peptides, the mechanical properties of the hydrogel, and neuron seeding density to achieve maximum cell viability, neurite projection, and synaptic connectivity (as determined by electrophysiological measurements, immunostaining, and viral tracing). Optimization of iPSC-derived mDANs in hydrogels is the first step to developing a novel in vitro model of PD to study disease propagation and screen therapeutic candidates.