Miah Mahjabeen, Ferretti Patrizia, Choi David
Spinal Repair Unit, Department of Brain Repair and Rehabilitation, UCL Queen Square Institute of Neurology, London, United Kingdom.
Developmental Biology and Cancer Department, UCL Great Ormond Street Institute of Child Health, London, United Kingdom.
Front Cell Neurosci. 2021 Nov 17;15:781489. doi: 10.3389/fncel.2021.781489. eCollection 2021.
Olfactory ensheathing cells (OECs) are specialized glia cells of the olfactory system that support the continual regeneration of olfactory neurons throughout adulthood. Owing to their pro-regenerative properties, OECs have been transplanted in animal models of spinal cord injuries (SCI) and trialed in clinical studies on SCI patients. Although these studies have provided convincing evidence to support the continued development of OEC transplantation as a treatment option for the repair of SCI, discrepancies in the reported outcome has shown that OEC transplantation requires further improvement. Much of the variability in the reparative potential of OEC transplants is due to the variations in the cell composition of transplants between studies. As a result, the optimal cell preparation is currently a subject of debate. Here we review, the characterization as well as the effect of the cell composition of olfactory cell transplantation on therapeutic outcome in SCI. Firstly, we summarize and review the cell composition of olfactory cell preparations across the different species studied prior to transplantation. Since the purity of cells in olfactory transplants might affect the study outcome we also examine the effect of the proportions of OECs and the different cell types identified in the transplant on neuroregeneration. Finally, we consider the effect of the yield of cells on neuroregeneration by assessing the cell dose of transplants on therapeutic outcome.
嗅鞘细胞（OECs）是嗅觉系统中的特殊神经胶质细胞，在成年期支持嗅觉神经元的持续再生。由于其促进再生的特性，嗅鞘细胞已被移植到脊髓损伤（SCI）的动物模型中，并在脊髓损伤患者的临床研究中进行了试验。尽管这些研究提供了令人信服的证据来支持将嗅鞘细胞移植作为脊髓损伤修复的治疗选择继续发展，但报告结果的差异表明嗅鞘细胞移植需要进一步改进。嗅鞘细胞移植修复潜力的很大一部分差异是由于不同研究之间移植细胞组成的变化。因此，最佳细胞制备方法目前仍是一个有争议的话题。在这里，我们综述了嗅细胞移植的细胞组成特征及其对脊髓损伤治疗结果的影响。首先，我们总结并回顾了移植前不同研究物种的嗅细胞制剂的细胞组成。由于嗅移植中细胞的纯度可能会影响研究结果，我们还研究了移植中嗅鞘细胞比例和不同细胞类型对神经再生的影响。最后，我们通过评估移植细胞剂量对治疗结果的影响来考虑细胞产量对神经再生的作用。
