title: Functional Maturation of Human Stem Cell-Derived Neurons in Long-Term Cultures.
abstract: Differentiated neurons can be rapidly acquired, within days, by inducing stem cells to express neurogenic transcription factors. We developed a protocol to maintain long-term cultures of human neurons, called iNGNs, which are obtained by inducing Neurogenin-1 and Neurogenin-2 expression in induced pluripotent stem cells. We followed the functional development of iNGNs over months and they showed many hallmark properties for neuronal maturation, including robust electrical and synaptic activity. Using iNGNs expressing a variant of channelrhodopsin-2, called CatCh, we could control iNGN activity with blue light stimulation. In combination with optogenetic tools, iNGNs offer opportunities for studies that require precise spatial and temporal resolution. iNGNs developed spontaneous network activity, and these networks had excitatory glutamatergic synapses, which we characterized with single-cell synaptic recordings. AMPA glutamatergic receptor activity was especially dominant in postsynaptic recordings, whereas NMDA glutamatergic receptor activity was absent from postsynaptic recordings but present in extrasynaptic recordings. Our results on long-term cultures of iNGNs could help in future studies elucidating mechanisms of human synaptogenesis and neurotransmission, along with the ability to scale-up the size of the cultures.
authors.affiliation: Department of Biophysical Chemistry, Max Planck Institute of Biophysics, Frankfurt, Germany.
authors.forename: Rebecca S
authors.identifier: http://orcid.org/0000-0002-9574-5712
authors.initials: RS
authors.lastname: Lam
authors.affiliation: Department of Biophysical Chemistry, Max Planck Institute of Biophysics, Frankfurt, Germany.
authors.forename: Felix M
authors.initials: FM
authors.lastname: Töpfer
authors.affiliation: Department of Biophysical Chemistry, Max Planck Institute of Biophysics, Frankfurt, Germany.
authors.forename: Phillip G
authors.initials: PG
authors.lastname: Wood
authors.affiliation: Center for Regenerative Therapies Dresden, TU-Dresden, Germany.
authors.forename: Volker
authors.initials: V
authors.lastname: Busskamp
authors.affiliation: Department of Biophysical Chemistry, Max Planck Institute of Biophysics, Frankfurt, Germany.
authors.forename: Ernst
authors.initials: E
authors.lastname: Bamberg
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000166:cytology / Q000378:metabolism / Q000528:radiation effects; D051792:Basic Helix-Loop-Helix Proteins / Q000378:metabolism; D002454:Cell Differentiation / Q000528:radiation effects; D002478:Cells, Cultured; D055724:Electrophysiological Phenomena / Q000528:radiation effects; D019706:Excitatory Postsynaptic Potentials / Q000528:radiation effects; D006801:Humans; D057026:Induced Pluripotent Stem Cells / Q000166:cytology* / Q000378:metabolism / Q000528:radiation effects; D008027:Light; D009419:Nerve Tissue Proteins / Q000378:metabolism; D055495:Neurogenesis / Q000528:radiation effects; D009474:Neurons / Q000166:cytology* / Q000378:metabolism / Q000528:radiation effects; D051381:Rats; D018092:Kainic Acid Receptors / Q000378:metabolism; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism; D013569:Synapses / Q000378:metabolism / Q000528:radiation effects; D016704:Synapsins / Q000378:metabolism; D013997:Time Factors
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D009419:Nerve Tissue Proteins; D018092:Kainic Acid Receptors; D016194:Receptors, N-Methyl-D-Aspartate; D016704:Synapsins; C105389:NEUROG1 protein, human; C491183:NEUROG2 protein, human