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. 2016 Oct 20;13(5):585–600. doi: 10.1007/s13770-016-9115-0

Functional recovery not correlated with axon regeneration through olfactory ensheathing cell-seeded scaffolds in a model of acute spinal cord injury

Haktan Altinova 1,2,3,4,✉, Sven Möllers 5, Ronald Deumens 2,3,6, Jose Gerardo-Nava 2,3, Tobias Führmann 7, Sabien Geraldine Antonia van Neerven 8, Ahmet Bozkurt 8,9, Christian Andreas Mueller 4, Hans Joachim Hoff 1, Ingo Heschel 10, Joachim Weis 2,3, Gary Anthony Brook 2,3
PMCID: PMC6170848  PMID: 30603440

Abstract

The implantation of bioengineered scaffolds into lesion-induced gaps of the spinal cord is a promising strategy for promoting functional tissue repair because it can be combined with other intervention strategies. Our previous investigations showed that functional improvement following the implantation of a longitudinally microstructured collagen scaffold into unilateral mid-cervical spinal cord resection injuries of adult Lewis rats was associated with only poor axon regeneration within the scaffold. In an attempt to improve graft-host integration as well as functional recovery, scaffolds were seeded with highly enriched populations of syngeneic, olfactory bulb-derived ensheathing cells (OECs) prior to implantation into the same lesion model. Regenerating neurofilament-positive axons closely followed the trajectory of the donor OECs, as well as that of the migrating host cells within the scaffold. However, there was only a trend for increased numbers of regenerating axons above that supported by non-seeded scaffolds or in the untreated lesions. Nonetheless, significant functional recovery in skilled forelimb motor function was observed following the implantation of both seeded and non-seeded scaffolds which could not be correlated to the extent of axon regeneration within the scaffold. Mechanisms other than simple bridging of axon regeneration across the lesion must be responsible for the improved motor function.

Key Words: Collagen, Scaffold, Olfactory ensheathing cells, Spinal cord injury, Functional recovery

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