Partial recovery of proprioception in rats with dorsal root injury following human olfactory bulb cell transplantation

We transplanted human olfactory bulb OECs (hOECs) mixed with collagen into a unilateral transection of four dorsal roots (C6-T1) in a rat model. By mixing with collagen, we could maximise the limited numbers of hOEC from an olfactory bulb biopsy and optimise cavity-filling. Cyclosporine was administered daily to prevent immune rejection. Forelimb proprioception was assessed weekly in a vertical climb task. Half of the rats receiving hOEC transplants showed some functional improvement (‘responders’) over six weeks of the study whilst the other half did not (‘non-responders’) and performed similarly to ‘injured only’ rats. Transplanted cells were seen at both 1 week and 6 weeks after surgery; many were concentrated within the lesion cavity but others were found with elongated processes in the overlying connective tissue. There were some fibres in the injury area associated with transplanted cells which were immunostained for neurofilament and TUJ1. We compared responder and non-responder rats with regard to...