Chan Candy K, Pham Lucia N, Chinn Cynthia, Spee Christine, Ryan Stephen J, Akhurst Rosemary J, Hinton David R
Department of Pathology, The Arnold and Mabel Beckman Macular Research Center at the Doheny Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, California 90033, USA.
Invest Ophthalmol Vis Sci. 2004 Feb;45(2):441-7. doi: 10.1167/iovs.03-0869.
Heterogeneity of the extent of angiogenesis induced by exogenous growth factors may be determined by genetic influences. Because angiogenesis is the formation of new vessels from preexisting ones, strain-related influences on naïve resting limbal vessel phenotype and gene expression were determined in mice having divergently low and high angiogenic responses.
Resting limbal vessel surface area and density and extent of bFGF-induced corneal angiogenesis were determined in C57BL/6J, BALB/cJ, F1 intercross identical with C57BL/6J X 129S3/SvIM, and 129S3/SvIM mouse strains by quantitative three-dimensional reconstruction confocal microscopy. Strain-related influences on pro- and antiangiogenic gene expression in naïve cornea were determined by quantitative real-time RT-PCR.
The strain-dependent rank order of resting limbal vessel surface area and resting vessel density paralleled bFGF-induced neovascularization: 129S3/SvIM > BALB/cJ, F1 > C57BL/6J (P < 0.0006). Pigment epithelium-derived factor (PEDF) was increased more than 67-fold compared to Ang-2 in resting cornea of both C57BL/6J and 129S3/SvIM strains (P < 0.0001; P < 0.0001), suggesting a strongly antiangiogenic environment. The corneas of the C57BL/6J mice demonstrated 1.8-, 1.5-, and 1.7-fold increased mRNA levels for Flt-1, VEGF, and bFGF, respectively (P < 0.02; P < 0.04; P < 0.02); however, TSP-1 expression was increased 2.4-fold compared with 129S3/SvIM (P < 0.0004).
Strain-dependent differences in the resting limbal vessel surface area and density correlated with heterogeneity in the extent of bFGF-induced angiogenesis. Differences in pro- and antiangiogenic gene expression levels in resting cornea may influence vascular limbal phenotype during quiescence and may predict susceptibility to angiogenesis-dependent diseases.
外源性生长因子诱导的血管生成程度的异质性可能由基因影响决定。由于血管生成是从已有的血管形成新血管，因此在血管生成反应分别极低和极高的小鼠中，确定了品系相关对原始静止角膜缘血管表型和基因表达的影响。
通过定量三维重建共聚焦显微镜，测定C57BL/6J、BALB/cJ、与C57BL/6J×129S3/SvIM相同的F1杂交种以及129S3/SvIM小鼠品系中静止角膜缘血管表面积、密度以及碱性成纤维细胞生长因子（bFGF）诱导的角膜血管生成程度。通过定量实时逆转录聚合酶链反应（RT-PCR）确定品系相关对原始角膜中促血管生成和抗血管生成基因表达的影响。
静止角膜缘血管表面积和静止血管密度的品系依赖性排序与bFGF诱导的新生血管形成情况平行：129S3/SvIM＞BALB/cJ、F1＞C57BL/6J（P＜0.0006）。在C57BL/6J和129S3/SvIM品系的静止角膜中，色素上皮衍生因子（PEDF）比血管生成素-2（Ang-2）增加超过67倍（P＜0.0001；P＜0.0001），表明存在强烈的抗血管生成环境。C57BL/6J小鼠的角膜中，Flt-1、血管内皮生长因子（VEGF）和bFGF的mRNA水平分别升高1.8倍、1.5倍和1.7倍（P＜0.02；P＜0.04；P＜0.02）；然而，与129S3/SvIM相比，血小板反应蛋白-1（TSP-1）表达升高2.4倍（P＜0.0004）。
静止角膜缘血管表面积和密度的品系依赖性差异与bFGF诱导的血管生成程度的异质性相关。静止角膜中促血管生成和抗血管生成基因表达水平的差异可能影响静止期角膜缘血管表型，并可能预测对血管生成依赖性疾病的易感性。
