McGill Trevor J, Bohana-Kashtan Osnat, Stoddard Jonathan W, Andrews Michael D, Pandit Neelay, Rosenberg-Belmaker Lior R, Wiser Ofer, Matzrafi Limor, Banin Eyal, Reubinoff Benjamin, Netzer Nir, Irving Charles
Casey Eye Institute, Oregon Health & Science University (OHSU), Portland, OR, USA.
Department of Neuroscience, Oregon National Primate Research Center, OHSU, Beaverton, OR, USA.
Transl Vis Sci Technol. 2017 Jun 14;6(3):17. doi: 10.1167/tvst.6.3.17. eCollection 2017 Jun.
Retinal pigment epithelium (RPE) dysfunction underlies the retinal degenerative process in age-related macular degeneration (AMD), and thus RPE cell replacement provides an optimal treatment target. We characterized longitudinally the efficacy of RPE cells derived under xeno-free conditions from clinical and xeno-free grade human embryonic stem cells (OpRegen) following transplantation into the subretinal space of Royal College of Surgeons (RCS) rats.
Postnatal (P) day 20 to 25 RCS rats ( = 242) received a single subretinal injection of 25,000 (low)-, 100,000 (mid)-, or 200,000 (high)-dose xeno-free RPE cells. BSS+ (balanced salt solution) (vehicle) and unoperated eyes served as controls. Optomotor tracking (OKT) behavior was used to quantify functional efficacy. Histology and immunohistochemistry were used to evaluate photoreceptor rescue and transplanted cell survival at 60, 100, 150, and 200 days of age.
OKT was rescued in a dose-dependent manner. Outer nuclear layer (ONL) was significantly thicker in cell-treated eyes than controls up to P150. Transplanted RPE cells were identified in both the subretinal space and integrated into the host RPE monolayer in animals of all age groups, and often contained internalized photoreceptor outer segments. No pathology was observed.
OpRegen RPE cells survived, rescued visual function, preserved rod and cone photoreceptors long-term in the RCS rat. Thus, these data support the use of OpRegen RPE cells for the treatment of human RPE cell disorders including AMD.
Our novel xeno-free RPE cells minimize concerns of animal derived contaminants while providing a promising prospective therapy to the diseased retina.
视网膜色素上皮（RPE）功能障碍是年龄相关性黄斑变性（AMD）视网膜退行性病变的基础，因此RPE细胞替代是一个理想的治疗靶点。我们纵向表征了在无动物源条件下从临床级和无动物源级人类胚胎干细胞（OpRegen）获得的RPE细胞移植到皇家外科学院（RCS）大鼠视网膜下间隙后的疗效。
出生后（P）20至25天的RCS大鼠（n = 242）接受单次视网膜下注射25,000（低）、100,000（中）或200,000（高）剂量的无动物源RPE细胞。平衡盐溶液（BSS+）（赋形剂）和未手术的眼睛作为对照。使用视动跟踪（OKT）行为来量化功能疗效。组织学和免疫组织化学用于评估60、100、150和200日龄时光感受器的挽救情况和移植细胞的存活情况。
OKT以剂量依赖的方式得到挽救。在P150之前，细胞治疗组眼睛的外核层（ONL）明显比对照组厚。在所有年龄组的动物中，移植的RPE细胞在视网膜下间隙均被识别，并整合到宿主RPE单层中，且通常含有内化的光感受器外段。未观察到病理学变化。
OpRegen RPE细胞在RCS大鼠中存活、挽救了视觉功能并长期保存了视杆和视锥光感受器。因此，这些数据支持使用OpRegen RPE细胞治疗包括AMD在内的人类RPE细胞疾病。
我们新型的无动物源RPE细胞在最大程度减少对动物源污染物担忧的同时，为患病视网膜提供了一种有前景的前瞻性治疗方法。
