허혈손상망막에 이식된 성체줄기세포의 소재 및 운명

To investigate the differentiation potency of be engraft mesenchymal stem cells to the retinal cell population through the retina ischemia-reperfusion injury model of rat. Ischemic injury model was made by an elevation of intra-ocular pressure in young adult Sprague-Dawely rats. Adult stem cells of third passages labeled with DiI were applied by an intravitreous injection at 3, 5, and 7 days after the ischemia-reperfusion injury(PI), respectively, cared for 2 weeks, and in case of 7 days PI group were also cared for 4 and 6 weeks. For specification of engraft stem cells, immunofluorescent staining by antibodies against retinal neuronal marker molecules was done. Retinal ischemia led to reduce in both thickness and cell number, principally in the inner retina and to a lesser extent in the outer retina. DiI labeled stem cells were migrated and well associated with host retina tissue by 7 days PI. The retinas of stem cell engraft group were thicker than those of the ischemia group, however, and edematous caused maybe by cell suspension solution volume compared to those of normal control group. Stem cells were located mainly in the ganglion cell layer of 7 days PI engraft group, even though there was no co-localization of DiI and neuronal markers. These results suggest that stem cells influence endogenous neuroprotective mechanisms rather than differentiation into any retinal cell population against neuronal degeneration followed by ischemia injury. It has also been suggested that tissue-specific carriers are necessary for successful transplantation of stem cells into degenerated neral retinas.