Hong Thomas, Wood Ian, Hunter Daniel A, Yan Ying, Mackinnon Susan E, Wood Matthew D, Moore Amy M
Washington University School of Medicine, St. Louis, MO, USA.
Hand (N Y). 2021 Mar;16(2):157-163. doi: 10.1177/1558944719849115. Epub 2019 May 29.
Management of painful neuromas continues to challenge clinicians. Controlling axon growth to prevent neuroma has gained considerable traction. A logical extension of this idea is to therefore develop an approach to control and arrest axon growth. Given the limits in axonal regeneration across acellular nerve allografts (ANAs), these constructs could provide a means to reliably terminate axon regeneration from an injured nerve. The purpose of this study was to determine if attaching an ANA to an injured nerve could provide a means to control and limit axon regeneration in a predictable manner. Twenty (20) adult rats received a sciatic nerve transection, where only the proximal nerve was repaired using an ANA of variable length (0.5, 2.5, and 5.0 cm) or left unrepaired (control). The nerves were harvested 5 weeks post-operatively for gross and histomorphometric analysis. The extent of myelinated axons in regenerated tissue was quantified. At 5 weeks, limited axon regeneration within the ANAs was observed. All lengths of ANAs lead to reduced myelinated axon numbers in the most terminal tissue region compared to untreated injured nerve ( = .002). Additionally, ANA length 2.5 cm or greater did not contain any axons at the most terminal tissue region. This study demonstrates a proof of concept that ANAs attached to the proximal end of an injured nerve can limit axon growth in a controlled manner. Furthermore, the extent of axon growth from the injured nerve into the ANA is dependent on the ANA length.
疼痛性神经瘤的治疗仍然是临床医生面临的挑战。控制轴突生长以预防神经瘤已受到广泛关注。因此，这种想法的合理延伸是开发一种控制和阻止轴突生长的方法。鉴于脱细胞神经同种异体移植物（ANA）在轴突再生方面的局限性，这些构建体可以提供一种可靠地终止受损神经轴突再生的方法。本研究的目的是确定将ANA连接到受损神经上是否可以提供一种以可预测的方式控制和限制轴突再生的方法。二十只成年大鼠接受坐骨神经横断术，仅使用不同长度（0.5、2.5和5.0厘米）的ANA修复近端神经或不进行修复（对照）。术后5周收获神经进行大体和组织形态计量分析。对再生组织中有髓轴突的程度进行量化。在5周时，观察到ANA内轴突再生有限。与未治疗的受损神经相比，所有长度的ANA在最末端组织区域均导致有髓轴突数量减少（P = 0.002）。此外，2.5厘米或更长的ANA在最末端组织区域不包含任何轴突。本研究证明了一个概念验证，即连接到受损神经近端的ANA可以以可控的方式限制轴突生长。此外，从受损神经向ANA的轴突生长程度取决于ANA的长度。
