Torricelli Andre A M, Marino Gustavo K, Santhanam Abirami, Wu Jiahui, Singh Arun, Wilson Steven E
Cole Eye Institute, Cleveland Clinic, Cleveland, OH, United States; University of Sao Paulo, Sao Paulo, Brazil.
Cole Eye Institute, Cleveland Clinic, Cleveland, OH, United States.
Exp Eye Res. 2015 May;134:33-8. doi: 10.1016/j.exer.2015.03.016. Epub 2015 Mar 19.
The epithelial basement membrane (BM) is a specialized extracellular matrix that has been shown to have a critical role in corneal development, wound healing, and disease. Although the epithelial BM contributes to corneal homeostasis, relatively little is know about non-epithelial production of its components that may be important in defective regeneration of the epithelial basement membrane associated with opacity after photorefractive keratectomy. The purpose of the current study was to investigate stromal production of corneal epithelial BM proteins in wounded human corneas using immunohistochemistry. A total of five unwounded control eyes and five 30-min epithelial-wounded corneas were obtained from fresh corneoscleral buttons removed from human eyes enucleated due to choroidal melanoma with normal anterior segments. In the wounded corneas, an eight mm patch of central corneal epithelium and epithelial BM was removed with a Beaver blade when the patient was under general anesthesia. Immunohistochemical analyses were performed to detect perlecan and nidogen-2 proteins-important components of the epithelial BM lamina lucida and lamina densa zones. Perlecan and nidogen-2 proteins were detected in the BM itself and at low levels in keratocytes in all unwounded corneas. After epithelial injury, both perlecan and nidogen-2 were expressed at high levels in stromal keratocytes, including superficial keratocytes in the early phases of apoptosis. Thus, after epithelial and epithelial BM injury, stromal keratocytes contribute important perlecan and nidogen-2 components to the regenerating epithelial BM.
上皮基底膜（BM）是一种特殊的细胞外基质，已被证明在角膜发育、伤口愈合和疾病中起关键作用。尽管上皮BM有助于角膜稳态，但对于其成分的非上皮来源知之甚少，而这些成分可能在与屈光性角膜切除术后混浊相关的上皮基底膜再生缺陷中起重要作用。本研究的目的是使用免疫组织化学方法研究受伤人角膜中角膜上皮BM蛋白的基质产生情况。从因脉络膜黑色素瘤且前段正常而摘除的人眼新鲜角膜巩膜纽扣中获取了总共五只未受伤的对照眼和五只上皮损伤30分钟的角膜。在受伤的角膜中，当患者处于全身麻醉状态时，用 Beaver 刀片切除直径8毫米的中央角膜上皮和上皮BM。进行免疫组织化学分析以检测核心蛋白聚糖和巢蛋白-2蛋白，它们是上皮BM透明层和致密层的重要成分。在所有未受伤的角膜中，核心蛋白聚糖和巢蛋白-2蛋白在BM本身以及角膜细胞中低水平表达。上皮损伤后，核心蛋白聚糖和巢蛋白-2在基质角膜细胞中均高表达，包括凋亡早期的浅层角膜细胞。因此，上皮和上皮BM损伤后，基质角膜细胞为再生的上皮BM提供重要的核心蛋白聚糖和巢蛋白-2成分。
