Seiler M J, Aramant R B
Department of Ophthalmology and Visual Sciences, University of Louisville Medical School, KY 40292.
Brain Res Dev Brain Res. 1994 Jul 15;80(1-2):81-95. doi: 10.1016/0165-3806(94)90092-2.
The purpose of this study was to compare the development of photoreceptor and glial cells in human embryonic retinal transplants with the development of normal human embryonic retina (13-20 weeks postconception). Human embryonic retinal cells (donor age 6-11 weeks postconception) were transplanted to the retinas of adult immunosuppressed rat hosts. Host animals were killed when the transplants were of 13-37 weeks total age (donor age+survival time after surgery). Immunohistochemistry was performed with antibodies specific for neuron-specific enolase (NSE), synaptophysin (SYN), cone-specific opsins, rhodopsin, rod alpha-transducin, S-antigen, vimentin, cellular retinaldehyde-binding protein (CRALBP) and glial fibrillary acidic protein (GFAP). With regards to photoreceptors, NSE and SYN immunoreactive cones were seen in transplants from 14-16 weeks of age, but cone opsin immunoreactivity was not seen until 25 weeks. Developing graft rods became S-antigen immunoreactive at 17-18 weeks. At 20 weeks, inner segments and some cell somas of graft rods stained faintly for alpha-transducin and rhodopsin. At 31 and 37 weeks, inner and outer rod segments were intensely labelled for the rod-specific antigens. The grafts exhibited areas of varying maturation with different staining intensities. Concerning the glial cells, vimentin immunoreactivity was seen in the earliest transplants studied (total age 14-16 weeks), but only in stages older than 19 weeks was the immunoreactivity of graft Müller cells comparable in intensity to those of the host retina. Host Müller cells were immunoreactive for GFAP near the lesion site at all times. At 20 weeks, some GFAP immunoreactive processes were seen inside the graft, apparently coming from the host retina. At 25 weeks, faintly stained Müller cells intrinsic to the graft were observed, indicating a gliosis within the graft. Graft Müller cells were first seen to express CRALBP immunoreactivity at 19-20 weeks and, at 25 weeks, intense immunoreactivity was seen in the transplant, mostly in regions near the host. In the transplants only the Müller cells were stained, whereas both Müller and retinal pigment epithelium cells were CRALBP immunoreactive in the host retina. The development of human embryonic retinal transplants appears to parallel approximately normal in utero development. Transplant cones, rods and Müller cells all express their cell-specific proteins. The photoreceptors develop both inner and outer segments and contain several essential proteins for processing light. The transplants can reach a degree of maturity comparable to newborn retina.
本研究的目的是比较人类胚胎视网膜移植中光感受器和神经胶质细胞的发育与正常人类胚胎视网膜（受孕后13 - 20周）的发育情况。将人类胚胎视网膜细胞（供体年龄为受孕后6 - 11周）移植到成年免疫抑制大鼠宿主的视网膜中。当移植体的总年龄为13 - 37周（供体年龄 + 手术后存活时间）时，处死宿主动物。使用针对神经元特异性烯醇化酶（NSE）、突触素（SYN）、视锥细胞特异性视蛋白、视紫红质、视杆α - 转导蛋白、S - 抗原、波形蛋白、细胞视黄醛结合蛋白（CRALBP）和胶质纤维酸性蛋白（GFAP）的特异性抗体进行免疫组织化学分析。关于光感受器，在14 - 16周龄的移植体中可见NSE和SYN免疫反应性视锥细胞，但直到25周才可见视锥视蛋白免疫反应性。发育中的移植视杆在17 - 18周时变为S - 抗原免疫反应性。在20周时，移植视杆的内节和一些细胞体对α - 转导蛋白和视紫红质染色微弱。在31周和37周时，视杆内、外节被视杆特异性抗原强烈标记。移植体表现出不同成熟程度的区域，染色强度各异。关于神经胶质细胞，在最早研究的移植体（总年龄14 - 16周）中可见波形蛋白免疫反应性，但仅在19周以上阶段，移植的米勒细胞的免疫反应强度才与宿主视网膜的相当。宿主米勒细胞在病变部位附近始终对GFAP呈免疫反应性。在20周时，在移植体内可见一些GFAP免疫反应性突起，显然来自宿主视网膜。在25周时，观察到移植体固有的微弱染色的米勒细胞，表明移植体内存在胶质增生。移植的米勒细胞在19 - 20周时首次被观察到表达CRALBP免疫反应性，在25周时，在移植体中可见强烈的免疫反应性，主要在靠近宿主的区域。在移植体中只有米勒细胞被染色，而在宿主视网膜中米勒细胞和视网膜色素上皮细胞均为CRALBP免疫反应性。人类胚胎视网膜移植的发育似乎大致与子宫内的正常发育平行。移植的视锥细胞、视杆细胞和米勒细胞均表达其细胞特异性蛋白。光感受器发育出内节和外节，并含有几种处理光的必需蛋白。移植体可达到与新生视网膜相当的成熟程度。
