Division of Pediatric General and Thoracic Surgery, Center for Fetal and Placental Research, Cincinnati Children's Hospital Medical Center (CCHMC), Cincinnati, Ohio.
Department of Biomedical Engineering, Structural Tissue Evaluation and Engineering Laboratory, University of Cincinnati, Cincinnati, Ohio.
J Surg Res. 2019 Oct;242:62-69. doi: 10.1016/j.jss.2019.04.035. Epub 2019 May 6.
Current therapeutic materials for spina bifida repair showed a limited number of options in the market, and none of them have all the requirements as the ideal patch. In fact, sometimes the surgical procedures pose substantial challenges using different patches to fully cover the spina bifida lesion. For this purpose, a tailored patch made of poly (L-lactic acid) and poly (ε-caprolactone) blend was designed and validated in vitro to accomplish all these requirements but was never tested in vivo.
In our present study, the designed patch was analyzed in terms of rejection from the animal when implanted subcutaneously and as a dural substitute in the spinal cord. Inflammatory reaction (Iba1), astrogliosis (GFAP), was analyzed and functional interaction with spinal cord tissue assessing the (%motor-evoked potentials /compound motor action potential) by electrophysiology.
No evidence of adverse or inflammatory reactions was observed in both models of subcutaneous implantation, neither in the neural tissue as a dural substitute. No signs of astrogliosis in the neural tissue were observed, and no functional alteration with improvement of the motor-evoked potential's amplitude was detected after 4 wk of implantation as a dural substitute in the rat spinal cord.
Designed patch used as a dural substitute will apparently not produce inflammation, scar formation, or tethering cord and not induce any adverse effect on regular functions of the spinal cord. Further studies are needed to evaluate potential improvements of this novel polymeric patch in the spinal cord regeneration using spina bifida models.
目前用于修复脊柱裂的治疗材料在市场上选择有限，没有一种材料具有作为理想补丁的所有要求。事实上，有时使用不同的补丁来完全覆盖脊柱裂病变会给手术带来很大的挑战。为此，设计并验证了一种由聚（L-乳酸）和聚（ε-己内酯）共混物制成的定制补丁，以满足所有这些要求，但从未在体内进行过测试。
在本研究中，分析了设计的补丁在皮下植入时从动物体内排斥的情况，以及作为脊髓硬脑膜替代物的情况。通过电生理学分析了炎症反应（Iba1）和星形胶质细胞增生（GFAP），并评估了与脊髓组织的功能相互作用，评估了（%运动诱发电位/复合运动动作电位）。
在皮下植入的两种模型中，均未观察到不良反应或炎症反应的证据，在作为硬脑膜替代物的神经组织中也未观察到。在神经组织中未观察到星形胶质细胞增生的迹象，在作为大鼠脊髓硬脑膜替代物植入 4 周后，也未检测到运动诱发电位幅度的功能改变。
作为硬脑膜替代物使用的设计补丁显然不会引起炎症、瘢痕形成或束缚脊髓，也不会对脊髓的正常功能产生任何不良影响。需要进一步研究来评估这种新型聚合物补丁在使用脊柱裂模型进行脊髓再生方面的潜在改进。
