title: Synaptic inputs from stroke-injured brain to grafted human stem cell-derived neurons activated by sensory stimuli.
abstract: Transplanted neurons derived from stem cells have been proposed to improve function in animal models of human disease by various mechanisms such as neuronal replacement. However, whether the grafted neurons receive functional synaptic inputs from the recipient's brain and integrate into host neural circuitry is unknown. Here we studied the synaptic inputs from the host brain to grafted cortical neurons derived from human induced pluripotent stem cells after transplantation into stroke-injured rat cerebral cortex. Using the rabies virus-based trans-synaptic tracing method and immunoelectron microscopy, we demonstrate that the grafted neurons receive direct synaptic inputs from neurons in different host brain areas located in a pattern similar to that of neurons projecting to the corresponding endogenous cortical neurons in the intact brain. Electrophysiological in vivo recordings from the cortical implants show that physiological sensory stimuli, i.e. cutaneous stimulation of nose and paw, can activate or inhibit spontaneous activity in grafted neurons, indicating that at least some of the afferent inputs are functional. In agreement, we find using patch-clamp recordings that a portion of grafted neurons respond to photostimulation of virally transfected, channelrhodopsin-2-expressing thalamo-cortical axons in acute brain slices. The present study demonstrates, for the first time, that the host brain regulates the activity of grafted neurons, providing strong evidence that transplanted human induced pluripotent stem cell-derived cortical neurons can become incorporated into injured cortical circuitry. Our findings support the idea that these neurons could contribute to functional recovery in stroke and other conditions causing neuronal loss in cerebral cortex.
authors.affiliation: Laboratory of Stem Cells and Restorative Neurology, Lund Stem Cell Center, University Hospital, BMC B10, 221 84, Lund, Sweden.
authors.forename: Daniel
authors.initials: D
authors.lastname: Tornero
authors.affiliation: Bogomoletz Institute of Physiology, and State Institute of Genetic and Regenerative Medicine, 01024, Kyiv, Ukraine.
authors.forename: Oleg
authors.initials: O
authors.lastname: Tsupykov
authors.affiliation: Neuronano Research Center, Lund University, Scheelevägen 2, 223 81, Lund, Sweden.
authors.forename: Marcus
authors.initials: M
authors.lastname: Granmo
authors.affiliation: Laboratory of Stem Cells and Restorative Neurology, Lund Stem Cell Center, University Hospital, BMC B10, 221 84, Lund, Sweden.
authors.forename: Cristina
authors.initials: C
authors.lastname: Rodriguez
authors.affiliation: Laboratory of Stem Cells and Restorative Neurology, Lund Stem Cell Center, University Hospital, BMC B10, 221 84, Lund, Sweden.
authors.forename: Marita
authors.initials: M
authors.lastname: Grønning-Hansen
authors.affiliation: Neuronano Research Center, Lund University, Scheelevägen 2, 223 81, Lund, Sweden.
authors.forename: Jonas
authors.initials: J
authors.lastname: Thelin
authors.affiliation: Bogomoletz Institute of Physiology, and State Institute of Genetic and Regenerative Medicine, 01024, Kyiv, Ukraine.
authors.forename: Ekaterina
authors.initials: E
authors.lastname: Smozhanik
authors.affiliation: Laboratory of Stem Cells and Restorative Neurology, Lund Stem Cell Center, University Hospital, BMC B10, 221 84, Lund, Sweden.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Laterza
authors.affiliation: Laboratory of Stem Cells and Restorative Neurology, Lund Stem Cell Center, University Hospital, BMC B10, 221 84, Lund, Sweden.
authors.forename: Somsak
authors.initials: S
authors.lastname: Wattananit
authors.affiliation: Laboratory of Stem Cells and Restorative Neurology, Lund Stem Cell Center, University Hospital, BMC B10, 221 84, Lund, Sweden.
authors.forename: Ruimin
authors.initials: R
authors.lastname: Ge
authors.affiliation: Laboratory of Stem Cells and Restorative Neurology, Lund Stem Cell Center, University Hospital, BMC B10, 221 84, Lund, Sweden.
authors.forename: Jemal
authors.initials: J
authors.lastname: Tatarishvili
authors.affiliation: Developmental and Regenerative Neurobiology, Department of Experimental Medical Science, Wallenberg Neuroscience Center and Lund Stem Cell Center, Lund University, BMC A11, 221 84, Lund, Sweden.
authors.forename: Shane
authors.initials: S
authors.lastname: Grealish
authors.affiliation: Institute of Reconstructive Neurobiology, Life and Brain Center, University of Bonn, and German Center for Neurodegenerative Diseases (DZNE), Sigmund-Freud-Straße 25, D-53127, Bonn, Germany.
authors.forename: Oliver
authors.initials: O
authors.lastname: Brüstle
authors.affiliation: Bogomoletz Institute of Physiology, and State Institute of Genetic and Regenerative Medicine, 01024, Kyiv, Ukraine.
authors.forename: Galina
authors.initials: G
authors.lastname: Skibo
authors.affiliation: Developmental and Regenerative Neurobiology, Department of Experimental Medical Science, Wallenberg Neuroscience Center and Lund Stem Cell Center, Lund University, BMC A11, 221 84, Lund, Sweden.
authors.forename: Malin
authors.initials: M
authors.lastname: Parmar
authors.affiliation: Neuronano Research Center, Lund University, Scheelevägen 2, 223 81, Lund, Sweden.
authors.forename: Jens
authors.initials: J
authors.lastname: Schouenborg
authors.affiliation: Laboratory of Stem Cells and Restorative Neurology, Lund Stem Cell Center, University Hospital, BMC B10, 221 84, Lund, Sweden.
authors.forename: Olle
authors.initials: O
authors.lastname: Lindvall
authors.affiliation: Laboratory of Stem Cells and Restorative Neurology, Lund Stem Cell Center, University Hospital, BMC B10, 221 84, Lund, Sweden.
authors.forename: Zaal
authors.initials: Z
authors.lastname: Kokaia
mesh_terms: D000200:Action Potentials; D000344:Afferent Pathways / Q000502:physiology; D000818:Animals; D001921:Brain / Q000166:cytology / Q000648:ultrastructure; D001930:Brain Injuries / Q000209:etiology / Q000601:surgery*; D002461:Cell Line, Transformed; D002540:Cerebral Cortex / Q000378:metabolism / Q000473:pathology / Q000648:ultrastructure; D004195:Disease Models, Animal; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D006801:Humans; D057026:Induced Pluripotent Stem Cells / Q000502:physiology* / Q000637:transplantation*; D008239:Lysine / Q000031:analogs & derivatives / Q000378:metabolism; D008297:Male; D009474:Neurons / Q000502:physiology / Q000648:ultrastructure; D010751:Phosphopyruvate Hydratase / Q000378:metabolism; D051381:Rats; D011923:Rats, Nude; D017207:Rats, Sprague-Dawley; D020521:Stroke / Q000150:complications; D013569:Synapses / Q000502:physiology* / Q000648:ultrastructure; D020651:Ventral Thalamic Nuclei / Q000166:cytology
chemical_list: D010751:Phosphopyruvate Hydratase; C013411:biocytin; D008239:Lysine
keywords: functional integration; stem cells; stroke; synapses; transplantation