Demetriades Anna M, Deering Tye, Liu Hansheng, Lu Lili, Gehlbach Peter, Packer Jonathan D, Mac Gabhann Feilim, Popel Aleksander S, Wei Lisa L, Campochiaro Peter A
Department of Ophthalmology, The Johns Hopkins University, School of Medicine, Baltimore, MD, USA.
J Ocul Pharmacol Ther. 2008 Feb;24(1):70-9. doi: 10.1089/jop.2007.0061.
In this study, we investigated the penetration of various proteins into the mouse eye after a periocular injection of the protein or an adenoviral vector (Ad) expressing the protein.
At several time points after the injection, the retina, retinal pigmented epithelium/choroid, and sclera were dissected and enzyme-linked immunosorbent assays were performed.
After a periocular injection of AdsFlt-1.10, AdTGFbeta.10, or AdPEDF.11, choroidal levels of pigment epithelium-derived factor (PEDF) and transforming growth factor-beta (TGF-beta) were not significantly different from scleral levels, and choroidal levels of sFlt-1 (soluble Flt-1 or soluble VEGF receptor 1) were only moderately reduced from scleral levels, indicating that each of these proteins penetrate the sclera well. In contrast, retinal levels of each of the three proteins were low compared to choroidal levels, suggesting poor penetration into the retina. Levels of PEDF in the choroid peaked 2 h after a periocular injection of PEDF protein and returned to baseline between 6 and 24 h, and peak levels in the retina were 8.6% of peak choroidal levels. Levels of green fluorescent protein, a protein unlikely to have any binding sites in mouse tissues, peaked in the choroid 2 h after the periocular injection and were undetectable by 4 h, while peak levels in the retina were 64.3% of peak choroidal levels.
These data suggest that size and binding characteristics of proteins are likely to influence their ability to penetrate the eye from the periocular space, but in general, proteins as large as 50-75 kDa penetrate well into the choroid, but not into the retina. Periocular injections are feasible for the treatment of choroidal neovascularization with proteins or vectors that express them, but additional investigations are needed before they can be considered for treatment of retinal diseases.
在本研究中，我们研究了在眼周注射蛋白质或表达该蛋白质的腺病毒载体（Ad）后，各种蛋白质在小鼠眼中的穿透情况。
在注射后的几个时间点，解剖视网膜、视网膜色素上皮/脉络膜和巩膜，并进行酶联免疫吸附测定。
在眼周注射AdsFlt-1.10、AdTGFbeta.10或AdPEDF.11后，脉络膜中色素上皮衍生因子（PEDF）和转化生长因子-β（TGF-β）的水平与巩膜水平无显著差异，而脉络膜中sFlt-1（可溶性Flt-1或可溶性血管内皮生长因子受体1）的水平仅比巩膜水平适度降低，表明这些蛋白质中的每一种都能很好地穿透巩膜。相比之下，与脉络膜水平相比，这三种蛋白质在视网膜中的水平较低，表明其穿透视网膜的能力较差。眼周注射PEDF蛋白后，脉络膜中PEDF的水平在2小时达到峰值，并在6至24小时之间恢复到基线水平，视网膜中的峰值水平为脉络膜峰值水平的8.6%。绿色荧光蛋白在小鼠组织中不太可能有任何结合位点，眼周注射后2小时在脉络膜中达到峰值，4小时后无法检测到，而视网膜中的峰值水平为脉络膜峰值水平的64.3%。
这些数据表明，蛋白质的大小和结合特性可能会影响其从眼周间隙穿透眼睛的能力，但一般来说，高达50-75 kDa的蛋白质能很好地穿透脉络膜，但不能穿透视网膜。眼周注射对于用蛋白质或表达它们的载体治疗脉络膜新生血管是可行的，但在考虑将其用于治疗视网膜疾病之前，还需要进行更多的研究。
