Final Report Summary - REPROPARK (New experimental therapeutic approaches for Parkinson’s disease by direct DA neuronal reprogramming)
In ReproPark, we devised an innovative system to combine CRISPR/Cas9 gene targeting with direct neuronal reprogramming in order to specifically inactivate gene function only during the process of neuronal cell conversion. This represents a convenient and efficient single-step procedure to generate induced neurons with a targeted gene inactivation.
This program allowed us to explore new systems to culture human neurons to model brain circuits and synapse specificity. For this goal, we established long-term cultures of human neurons in a microfluidic platform to reconstitute the nigro-striatal pathway and the formation of functional DA synapses. The generation of functional in vitro circuitries with defined post- and pre-synaptic neuronal elements provides an accurate and sophisticated system to investigate both physiological and pathological processes. Further refinement of these technologies will lead to more elaborated designs to accommodate multiple neuronal populations for faithful and systematic modeling of complex brain networks.
Finally, ReproPark provided the first ever study describing the transplantation of iDA neurons in vivo, their functional integration in host brain networks and sustain a symptomatic rescue in PD mice. Thus, this work provides proof that direct neuronal reprogramming offers a method for obtaining stable and transplantable DA neurons suitable for cell replacement in a PD animal model. Moreover, we showed that DREADD technology can be efficiently applied to control activity of iNeurons in vivo. This combination is of extreme interest for DA cell replacement research and could pave the way for pharmacological approaches aimed at exerting efficient and noninvasive control of the grafted neuronal implant.