Abstract
Integration of stem cell-derived cells into native cellular environment remains a challenge in the field. This study developed novel methods to co-culture neural stem cell-derived spiral ganglion-like neurons (ScNs) and mouse auditory cochlear nucleus (CN) neurons to understand whether ScNs of the peripheral nervous system (PNS) synapse with CN neurons of the central nervous system (CNS). ScNs were obtained from neural stem cells that were derived from transgenic mouse pre-labeled with enhanced green fluorescent protein (EGFP), whereas CN neurons were from postnatal mouse primary cultures. ScNs and CN neurons were co-cultured for 4–6 days in the absence or presence of astrocyte-conditioned medium (ACM). Class III β-tubulin (TUJ1)-expressing connections were found between ScNs and CN neurons. Expression of the synaptic vesicle marker SV2 was significantly increased along connections between ScNs and CN neurons in the presence of ACM. Immunodepletion and knockout studies indicated that thrombospodin-1 played an important role in ACM-exerted synaptogenic effects. Newly-generated synapse-like structures expressed glutamatergic marker VGluT1, pre- and post-synaptic proteins. Synaptic vesicle recycling studies suggested functional synaptic vesicle retrieval. These results reveal that stem cell-derived PNS neurons are able to form functional connections with native CNS neurons, which is critical for stem cell-based neural pathway regeneration.
Highlights
Stem cell-based replacement has been suggested for regenerative medicine for a couple of decades
Because cochlear nucleus (CN) neurons were expected to co-culture with stem cell-derived spiral ganglion-like neurons (ScNs), nerve growth factor (NGF) was added to the culture medium to support the survival of CN neurons
We developed a novel stem cell-based co-culture system to understand whether mouse stem cell-derived peripheral nervous system (PNS) neurons were able to form synaptic connections with mouse central nervous system (CNS) neurons
Summary
Stem cell-based replacement has been suggested for regenerative medicine for a couple of decades. These studies suggest that SGN-like neurons can be generated from pluripotent and multipotent stem cells It remains unclear whether stem cell-derived neurons are able to integrate into the native auditory system, which at least includes neurite connections, myelination, and neural circuit function. The PNS-CNS connection of the auditory system resides within the bony temporal bone, which largely limits the access for in vivo research To address these complicated issues, it is helpful to establish an in vitro stem cell-based co-culture model. Previous studies indicated that astrocyte conditioned medium (ACM) and thrombospodin-1 (TSP1) were able to stimulate synapse formation of CNS neurons in vitro[16,17], which was supported by a recent report in the application of ACM to ScN cultures[10]. We utilize our newly-developed co-culture system to determine whether ACM and TSP1 induce synaptogenesis between ScNs and CN neurons
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
