Nazareth Lynnmaria, Tello Velasquez Johana, Lineburg Katie E, Chehrehasa Fatemeh, St John James A, Ekberg Jenny A K
School of Biomedical Sciences, Queensland University of Technology, Brisbane, 4000 Queensland, Australia; Eskitis Institute for Drug Discovery, Griffith University, Nathan, 4111 Queensland, Australia.
Eskitis Institute for Drug Discovery, Griffith University, Nathan, 4111 Queensland, Australia.
Mol Cell Neurosci. 2015 Mar;65:92-101. doi: 10.1016/j.mcn.2015.03.005. Epub 2015 Mar 6.
The rodent olfactory systems comprise the main olfactory system for the detection of odours and the accessory olfactory system which detects pheromones. In both systems, olfactory axon fascicles are ensheathed by olfactory glia, termed olfactory ensheathing cells (OECs), which are crucial for the growth and maintenance of the olfactory nerve. The growth-promoting and phagocytic characteristics of OECs make them potential candidates for neural repair therapies such as transplantation to repair the injured spinal cord. However, transplanting mixed populations of glia with unknown properties may lead to variations in outcomes for neural repair. As the phagocytic capacity of the accessory OECs has not yet been determined, we compared the phagocytic capacity of accessory and main OECs in vivo and in vitro. In normal healthy animals, the accessory OECs accumulated considerably less axon debris than main OECs in vivo. Analysis of freshly dissected OECs showed that accessory OECs contained 20% less fluorescent axon debris than main OECs. However, when assayed in vitro with exogenous axon debris added to the culture, the accessory OECs phagocytosed almost 20% more debris than main OECs. After surgical removal of one olfactory bulb which induced the degradation of main and accessory olfactory sensory axons, the accessory OECs responded by phagocytosing the axon debris. We conclude that while accessory OECs have the capacity to phagocytose axon debris, there are distinct differences in their phagocytic capacity compared to main OECs. These distinct differences may be of importance when preparing OECs for neural transplant repair therapies.
啮齿动物的嗅觉系统包括用于检测气味的主嗅觉系统和检测信息素的副嗅觉系统。在这两个系统中，嗅觉轴突束都被嗅觉胶质细胞包裹，这些细胞被称为嗅觉鞘细胞（OECs），它们对嗅觉神经的生长和维持至关重要。OECs的促生长和吞噬特性使其成为神经修复疗法（如移植以修复受损脊髓）的潜在候选者。然而，移植具有未知特性的混合胶质细胞群体可能会导致神经修复结果的差异。由于副OECs的吞噬能力尚未确定，我们比较了副OECs和主OECs在体内和体外的吞噬能力。在正常健康动物中，副OECs在体内积累的轴突碎片比主OECs少得多。对新鲜解剖的OECs的分析表明，副OECs所含的荧光轴突碎片比主OECs少20%。然而，当在体外添加外源轴突碎片进行检测时，副OECs吞噬的碎片比主OECs多近20%。在手术切除一个嗅球后，主嗅觉和副嗅觉感觉轴突发生降解，副OECs通过吞噬轴突碎片做出反应。我们得出结论，虽然副OECs有吞噬轴突碎片的能力，但与主OECs相比，它们的吞噬能力存在明显差异。在为神经移植修复疗法准备OECs时，这些明显差异可能很重要。
