Endo Takeshi, Kadoya Ken, Kawamura Daisuke, Iwasaki Norimasa
Department of Orthopaedic Surgery, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan.
Exp Physiol. 2019 Oct;104(10):1447-1454. doi: 10.1113/EP087634. Epub 2019 Aug 11.
What is the central question of this study? Although the factors secreted from Schwann cells that promote axonal growth in the peripheral nervous system have been well studied, the effect of cell-contact factors on Schwann cells remains to be determined. What is the main finding and its importance? This study demonstrates that Schwann cells stimulate neurite outgrowth by direct contact with neurites and by secreting factors. Notably, the effect of cell-contact factors in neurite outgrowth is comparable to that of secreted factors, indicating that the identification of cell surface molecules on Schwann cells that promote neurite outgrowth could lead to development of a new therapy for peripheral nervous system injury.
Schwann cells (SCs) play a variety of roles in the regeneration process after injury to the peripheral nervous system. The factors secreted from SCs that promote axonal growth have been well studied. However, the involvement of cell-contact factors on SCs remains to be determined. Here, we demonstrate a significant contribution of a cell-contact mechanism in the effect of SCs on promotion of neuronal outgrowth. Neurite outgrowth of adult sensory neurons from dorsal root ganglia was quantified during co-culture with adult SCs. Direct contact of SCs with neurons was eliminated by culturing SCs on an insert placed in the same well; this resulted in a 51% reduction in the length of neurite outgrowth. In addition, when dorsal root ganglion neurons were cultured on sparsely seeded SCs, neurons that made contact with SCs on their neurites had 118% longer neurites than neurons that lacked contacts with SCs. Collectively, these findings provide evidence that SCs stimulate neurite outgrowth via direct contact with neurites in addition to secreting factors. The identification of cell surface molecules on SCs that promote neurite outgrowth could lead to development of a new therapy for peripheral nervous system injury.
本研究的核心问题是什么？尽管雪旺细胞分泌的促进周围神经系统轴突生长的因子已得到充分研究，但细胞接触因子对雪旺细胞的影响仍有待确定。主要发现及其重要性是什么？本研究表明，雪旺细胞通过与神经突直接接触和分泌因子来刺激神经突生长。值得注意的是，细胞接触因子在神经突生长中的作用与分泌因子相当，这表明鉴定雪旺细胞上促进神经突生长的细胞表面分子可能会带来一种针对周围神经系统损伤的新疗法。
雪旺细胞（SCs）在周围神经系统损伤后的再生过程中发挥着多种作用。雪旺细胞分泌的促进轴突生长的因子已得到充分研究。然而，细胞接触因子对雪旺细胞的影响仍有待确定。在此，我们证明了细胞接触机制在雪旺细胞促进神经元生长的作用中具有重要贡献。在与成年雪旺细胞共培养期间，对来自背根神经节的成年感觉神经元的神经突生长进行了量化。通过将雪旺细胞培养在置于同一孔中的插入物上来消除雪旺细胞与神经元的直接接触；这导致神经突生长长度减少了51%。此外，当背根神经节神经元培养在稀疏接种的雪旺细胞上时，其神经突与雪旺细胞接触的神经元的神经突长度比未与雪旺细胞接触的神经元长118%。总的来说，这些发现提供了证据，表明雪旺细胞除了分泌因子外，还通过与神经突直接接触来刺激神经突生长。鉴定雪旺细胞上促进神经突生长的细胞表面分子可能会带来一种针对周围神经系统损伤的新疗法。
