Wojciechowski Anita Blixt, Englund Ulrica, Lundberg Cecilia, Warfvinge Karin
Wallenberg Retina Center, Department of Ophthalmology, Lund University Hospital, S-221 84 Lund, Sweden.
Stem Cells. 2002;20(2):163-73. doi: 10.1634/stemcells.20-2-163.
The potential use of in vitro-expanded precursor cells or cell lines in repair includes transplantation of such cells for cell replacement purposes and the activation of host cells to provide "self-repair." Recently, we have reported that cells from the brain-derived cell line RN33B (derived from the embryonic rat medullary raphe and immortalized through retroviral transduction of the temperature-sensitive mutant of the simian virus 40 ([SV40] large T-antigen) survive for at least 4 weeks, integrate, and differentiate after subretinal grafting to normal adult rats. Here, we demonstrate that grafts of these cells survive for at least 4 months after subretinal transplantation to adult, normal immunosuppressed rats. Implanted cells integrate into the retinal pigment epithelium and the inner retinal layers, and the anterior part of the optic nerve. In addition, the RN33B cells migrate within the retina, occupying the whole retina from one eccentricity to the other. A large fraction of the grafted cells differentiate into glial cells, as shown by double labeling of the reporter genes LacZ or green fluorescent protein, and several glial markers, including oligodendrocytes. However, the cells did not differentiate into retinal neurons, judging from their lack of expression of retinal neuronal phenotypic markers. A significant number of the implanted cells in the host retina were in a proliferative stage, judging from proliferative cell nuclear antigen and SV40 large T-antigen immunohistochemistry. To conclude, the cells survived, integrated, and migrated over long distances within the host. Therefore, our results may be advantageous for future design of therapeutic strategies, since such cells may have the potential of being a source of, for example, growth factor delivery in experimental models of retinal degeneration.
体外扩增的前体细胞或细胞系在修复中的潜在用途包括移植此类细胞以进行细胞替代，以及激活宿主细胞以实现“自我修复”。最近，我们报道了源自脑源性细胞系RN33B的细胞（该细胞系源自胚胎大鼠延髓中缝，通过猿猴病毒40（[SV40]）大T抗原温度敏感突变体的逆转录病毒转导而永生化）在视网膜下移植到正常成年大鼠后至少存活4周，并整合和分化。在此，我们证明，将这些细胞视网膜下移植到成年正常免疫抑制大鼠后，移植细胞至少存活4个月。植入的细胞整合到视网膜色素上皮、视网膜内层以及视神经前部。此外，RN33B细胞在视网膜内迁移，从一个偏心度占据整个视网膜到另一个偏心度。如报告基因LacZ或绿色荧光蛋白与包括少突胶质细胞在内的几种神经胶质细胞标志物的双重标记所示，大部分移植细胞分化为神经胶质细胞。然而，从它们缺乏视网膜神经元表型标志物的表达来看，这些细胞没有分化为视网膜神经元。从增殖细胞核抗原和SV40大T抗原免疫组织化学判断，宿主视网膜中大量植入细胞处于增殖阶段。总之，这些细胞在宿主体内存活、整合并远距离迁移。因此，我们的结果可能有利于未来治疗策略的设计，因为此类细胞可能具有成为例如视网膜变性实验模型中生长因子递送来源的潜力。
