Axonal signalling and the making of olfactory ensheathing cells: a hypothesis.
Axonal signalling and the making of olfactory ensheathing cells: a hypothesis.
复制标题
轴突信号传导和嗅觉鞘细胞的形成：一个假设。
作者：
K. Wewetzer;G. Brandes
嗅鞘细胞（OECs）是嗅觉系统的雪旺细胞样胶质细胞，在实验条件下促进神经修复。这是一个有争议的问题，在多大程度上OEC类似于许旺细胞，以及它们是否具有特定的属性。虽然嗅鞘细胞的特点主要是关于其移植后的再生效果，其细胞的身份和所涉及的调节因子仍然模糊。本文的目的是定义OEC和许旺细胞的身份在分子方面，并讨论参与在体外和体内确定的关键因素。不同的OEC功能，如神经元接触的低亲和力神经营养因子受体p75（NTR）的下调是明显的，在体内生理条件下，而OEC获得雪旺细胞样表型和上调p75（NTR）的表达在体外和移植到受损的脊髓。这可能表明OEC表型的建立依赖于特定的轴突刺激。在这篇综述中，我们假设嗅鞘细胞和许旺细胞具有可塑性的细胞表型，获得独特的功能，只有在特定的相互作用与他们的天然neuronal partner.This概念是一致的，在体外和体内以前的研究结果，并可能是相关的研究，使用嗅鞘细胞和许旺细胞的神经系统修复。
Olfactory ensheathing cells (OECs) are Schwann cell-like glial cells of the olfactory system that promote neural repair under experimental conditions. It is a matter of debate in how far OECs resemble Schwann cells and whether they possess specific properties. Although OECs have been characterized mainly with respect to their regenerative effects after transplantation, both their cellular identity and the regulating factors involved have remained vague. The aim of this article is to define OEC and Schwann-cell identity in molecular terms, and to discuss crucial factors that are involved in determination in vitro and in vivo. Distinct OEC features such as the down-regulation of the low affinity neurotrophin receptor p75(NTR) by neuronal contact are apparent in vivo under physiological conditions, whereas OECs acquire a Schwann cell-like phenotype and up-regulate p75(NTR) expression in vitro and following transplantation into the lesioned spinal cord. This might indicate that establishment of the OEC phenotype depends on specific axonal stimuli. In this review we hypothesize that OECs and Schwann cells possess malleable cellular phenotypes that acquire distinct features only upon specific interaction with their natural neuronal partner.This concept is consistent with previous findings in vitro and in vivo, and might be relevant for studies that use OECs and Schwann cells for nervous system repair.