Biology Faculty, Lomonosov Moscow State University.
Acta Naturae. 2011 Oct;3(4):66-72.
The use of stem cell technologies in retinal defect reparation therapy has produced beneficial results. Nowadays, numerous protocols exist which provide a neural differentiation of the stem cells transplanted into the retina. However, questions concerning the functional replacement of the missing retinal neurons by transplanted cells thus far remain unanswered. The organotypic culture protocol was used in this study in order to prove the possibility of transdifferentiation of bone marrow stromal cells (MMSCs) and neural stem/progenitor cells (NSPCs) from EGFP-positive mice and the functional integration of these cells. This technique enables a detailed characterization of cell behavior post-transplantation. Using atomic force microscopy, we reliably demonstrated the difference (p < 0.01) between the thickness of the outgrowths formed by glial and endothelial retina cells and the thickness of neurites and neuro-like transplanted MMSC outgrowths. MMSCs are also shown to form synapses up to 2.5 ± 0.06 µm in diameter on day 4 after the transplantation. Following electrical stimulation (20V, 0.5Hz, 200ms), clear depolarization of retinal neurons and their outgrowths is detected. It is shown that some of these GFP+ MMSCs, which changed their morphology after the transplantation in retinal explants to neuro-like MMSCs, are capable of depolarizing after exogenous stimulation.
干细胞技术在视网膜缺损修复治疗中的应用已经取得了有益的成果。如今，有许多方案可以提供将干细胞移植到视网膜后的神经分化。然而，关于移植细胞对缺失的视网膜神经元的功能替代问题，目前仍未得到解答。本研究采用器官型培养方案，以证明骨髓基质细胞（MMSC）和表皮生长因子阳性（EGFP+）小鼠来源的神经干细胞/祖细胞（NSPC）的转分化以及这些细胞的功能整合的可能性。该技术能够详细描述移植后细胞的行为。通过原子力显微镜，我们可靠地证明了神经胶质和内皮视网膜细胞形成的突起的厚度与神经突和类似神经元的移植 MMSC 突起的厚度之间存在差异（p<0.01）。还显示 MMSC 可以在移植后第 4 天形成直径达 2.5±0.06μm 的突触。在进行电刺激（20V，0.5Hz，200ms）后，检测到视网膜神经元及其突起的明显去极化。结果表明，在视网膜外植体中，一些形态在移植后发生变化的 GFP+MMSC 在受到外源性刺激后能够去极化。
