Feasibility of Three-Dimensional Placement of Human Therapeutic Stem Cells Using the Intracerebral Microinjection Instrument.
OBJECTIVE
The ability to safely place viable intracerebral grafts of human-derived therapeutic stem cells in three-dimensional (3D) space was assessed in a porcine model of human stereotactic surgery using the Intracerebral Microinjection Instrument (IMI) compared to a conventional straight cannula.


METHODS
Two groups of healthy minipigs received injections of the human stem cell line, NSI-566, into the right hemisphere and cell suspension carrier media into the left hemisphere. Group A received all injections using a straight, 21-gauge stainless steel cannula. Group B received all injections using the IMI, whereby radial distribution of injections was achieved via angular extension of a 196-micron diameter cannula from a single overlying penetration of the guide cannula. Each animal received six 20 µL intracerebral-injections within each hemisphere: three in a radial distribution, covering a 180° arc with each injection separated by a 60° arc distance, within both frontal cortex and basal ganglia. H&E and immunocytochemistry (HuNu and GFAP) were used to identify implanted cells and to assess tissue response.


RESULTS
The presence of surviving cells in appropriate brain regions demonstrated that the IMI is capable of accurately delivering viable human-derived stem cells safely in a 3D array at predetermined sites within the pig brain. In addition, qualitative evaluation of the target tissue suggests efficient delivery with decreased surgical trauma.


CONCLUSIONS
In contrast to traditional straight cannulas, the IMI enables the delivery of multiple precise cellular injection volumes in accurate 3D arrays. In this porcine large animal model of human neurosurgery, the IMI reduced surgical time and appeared to reduce neural trauma associated with multiple penetrations that would otherwise be required using a conventional straight delivery cannula.
Department of Neurosurgery, Aarhus University Hospital, Aarhus, Denmark.
Andreas Nørgaard
AN
Glud
Department of Neurosurgery, Institute of Clinical Medicine, Aalborg University Hospital, Aalborg, Denmark.
Carsten Reidies
CR
Bjarkam
Department of Psychiatry, Laboratory for Neural Reconstruction, McLean Hospital, Harvard Medical School, Boston, MA, USA.
Nima
N
Azimi
Neuralstem Inc., Rockville, MD, USA.
Karl
K
Johe
Department of Neurosurgery, Aarhus University Hospital, Aarhus, Denmark.
Jens Christian
JC
Sorensen
Department of Psychiatry, Laboratory for Neural Reconstruction, McLean Hospital, Harvard Medical School, Boston, MA, USA. mcunningham@mclean.harvard.edu.
Miles
M
Cunningham
D000818:Animals; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology; D000070642:Brain Injuries, Traumatic / Q000000981:diagnostic imaging / Q000601:surgery*; D004195:Disease Models, Animal; D053595:Embryonic Stem Cells / Q000502:physiology*; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D006801:Humans; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D008845:Microinjections / Q000379:methods*; D010751:Phosphopyruvate Hydratase / Q000378:metabolism; D033581:Stem Cell Transplantation / Q000379:methods*; D013552:Swine; D013556:Swine, Miniature
D005904:Glial Fibrillary Acidic Protein; D010751:Phosphopyruvate Hydratase
Functional neurosurgery; minimal invasive surgery; stem cell transplantation; stereotaxy; sus scrofa domesticus