Corneal wound healing and nerve regeneration

 描述(申请人提供)：角膜神经对于角膜的健康以及保护眼睛免受外界因素的影响都很重要。这些神经主要是伤害性感觉，编码对机械刺激、温度变化和/或化学刺激的不适和疼痛。疾病、感染和眼科手术都会损害角膜神经，造成疼痛、干眼、反复侵蚀、浑浊甚至失明等长期后果。然而，在临床实践中还没有有效的治疗方法来治疗神经功能障碍，我们将使用我们的猫的准分子激光屈光性角膜切削术(PRK)后角膜伤口愈合的模型，并结合体内和体外的方法来研究控制成人角膜损伤后神经再生的基本机制。我们的初步数据显示，不同神经层(间质、基底丛、上皮)的再神经支配明显异常，局部抗纤维化药物对神经再生的主要调节作用。这些数据表明，肌成纤维细胞对再生神经和/或与其相关的神经胶质细胞(非髓鞘雪旺细胞-NMSCs)具有抑制作用，这导致我们提出以下中心假设：对角膜大伤口的反应发生的肌成纤维细胞转化直接抑制神经再生。因此，在早期伤口愈合反应中阻断肌成纤维细胞的分化对于恢复角膜上皮和基质的正常神经支配至关重要。我们将通过以下方法验证这一假设：目的1-评估PRK后肌成纤维细胞分化对角膜神经再生和NMSCs的影响；目的2-评估阻断肌成纤维细胞分化对PRK后角膜神经再生和NMSCs的影响；目的3-角膜创伤情况。拟议的实验评估异常的角膜再神经支配对角膜光学的长期影响；以及目标4-在体外表征角膜成纤维细胞、肌成纤维细胞和感觉神经元之间的相互作用，并验证肌成纤维细胞通过Sema3A抑制轴突生长的假说。对伤口愈合过程中神经再生、神经-肌成纤维细胞的相互作用及其分子机制的系统研究对于开发新的治疗策略以促进最佳神经再生和确保眼表的长期健康至关重要。

 DESCRIPTION (provided by applicant): Corneal nerves are important for the health of the cornea, as well as for protecting the eye from outside elements. These nerves are predominantly nociceptive, coding discomfort and pain in response to mechanical stimulation, temperature change and/or chemical stimulation. Disease, infection and ocular surgery can all damage corneal nerves, with long-term consequences in terms of pain, dry eye, recurrent erosions, opacity and even blindness. Yet, there are no effective therapies in clinical practice fo treating nerve dysfunction in the will use our cat model of corneal wound healing after photorefractive keratectomy (PRK) and a combination of in vivo and in vitro approaches to study the basic mechanisms controlling adult, corneal nerve regeneration post-injury. Our preliminary data show clear abnormalities of re-innervation in different nerve layers (stroma, sub-basal plexus, epithelium) and major modulation of nerve regeneration by topical anti-fibrotics. These data suggest an inhibitory influence of myofibroblasts on regenerating nerves and/or their associated glia (non-myelinating Schwann cells - NMSCs), leading us to propose the following central hypothesis for this renewal application: myofibroblast transformation that occurs in response to large corneal wounds directly inhibits nerve regeneration. Thus, blocking myofibroblast differentiation during the early wound healing response is critical for restoring normal corneal innervation to the epithelium and stroma. We will test this hypothesis by: Aim 1 - assessing the impact of myofibroblast differentiation on corneal nerve regeneration and NMSCs after PRK; Aim 2 - assessing the effect of blocking myofibroblast differentiation on corneal nerve regeneration and NMSCs after PRK; Aim 3 - context of corneal wounds. The proposed experiments assessing the long-term impact of abnormal corneal re-innervation on corneal optics; and Aim 4 - characterizing the interactions between corneal fibroblasts, myofibroblasts and sensory neurons in vitro and testing the hypothesis that myofibroblasts inhibit neurite outgrowth via Sema3A. The proposed, systematic characterization of nerve regeneration, nerve-myofibroblast interactions and their molecular mechanisms during wound healing are critical for the development of new therapeutic strategies to treat corneal wounds with an eye to promoting optimal nerve regeneration and ensuring long-term health of the ocular surface.