Sheridan Carl M, Rice Deborah, Hiscott Paul S, Wong David, Kent David L
Department of Ophthalmology, School of Clinical Sciences, University of Liverpool, Liverpool, United Kingdom.
Invest Ophthalmol Vis Sci. 2006 Apr;47(4):1642-5. doi: 10.1167/iovs.05-0779.
Recent evidence suggests that vasculogenesis as well as angiogenesis occurs throughout the body during neovascularization. The recruitment of circulating stem cells is a key feature of vasculogenesis. The purpose of the present study was to determine whether markers of endothelial progenitor cells (EPCs) are present in choroidal neovascularization (CNV) secondary to age-related macular degeneration (AMD).
Surgically excised CNV (n = 9) membranes from patients with AMD were probed with immunohistochemical techniques using the following monoclonal antibodies: AC133 a putative marker of EPCs and hematopoietic stem cells (HSCs); the endothelial cells markers CD31, CD34, and von Willebrand factor (vWF); and cytokeratins and CD68, markers for retinal pigment epithelium (RPE) and macrophages, respectively. After secondary antibody amplification, reactions were visualized with fast red substrate.
Six of nine specimens demonstrated cells positive for AC133 that were all found within predominantly cellular regions of the specimens. In the avascular fibrous stromal core of all specimens, the predominant cells were RPE cells and macrophages. The peripheral component of all CNV membranes was highly vascular and showed varying immunoreactivity for all endothelial markers. The greatest immunoreactivity for endothelial markers was observed with CD34 and vWF and least for CD31.
These findings support animal studies that vasculogenesis, in addition to angiogenesis, may contribute to the neovascularization that occurs in AMD.
最近有证据表明，在新生血管形成过程中，血管生成以及血管新生在全身各处都会发生。循环干细胞的募集是血管生成的一个关键特征。本研究的目的是确定在年龄相关性黄斑变性（AMD）继发的脉络膜新生血管（CNV）中是否存在内皮祖细胞（EPC）标志物。
使用以下单克隆抗体，通过免疫组织化学技术对手术切除的AMD患者的CNV（n = 9）膜进行检测：AC133，一种假定的EPC和造血干细胞（HSC）标志物；内皮细胞标志物CD31、CD34和血管性血友病因子（vWF）；以及细胞角蛋白和CD68，分别为视网膜色素上皮（RPE）和巨噬细胞的标志物。二抗放大后，用固红底物使反应显色。
9个标本中有6个显示AC133阳性细胞，均位于标本的主要细胞区域内。在所有标本的无血管纤维基质核心中，主要细胞是RPE细胞和巨噬细胞。所有CNV膜的周边部分血管丰富，对所有内皮标志物均表现出不同程度的免疫反应性。内皮标志物的免疫反应性以CD34和vWF最强，CD31最弱。
这些发现支持了动物研究的结果，即除血管新生外，血管生成可能也参与了AMD中发生的新生血管形成。
