Subretinal Transplantation Of Müller Glia With Neural Stem Cell Properties Delay Photoreceptor Degeneration And Functional Deterioration In Rats

Objective The purpose of this study was to investigate whether subretinal transplantation of M(u|¨)ller cells with neural stem cell properties can rescue photoreceptor degeneration in RCS rat.Methods The mixed neurotoxins solution containing N-methyl-D-aspartate(NMDA),kainate,fibroblast growth factor-2(FGF2) and insulin was intravitreally injected in the right eyes of 10 6-week-old Vneversity College(VC) rats to activate M(u|¨)ller cells and the physical salt solution was injected in the left eyes as control. One week later,the activated M(u|¨)ller cells were gathered,cultured and purified.After being labeled with DAPI,the activated M(u|¨)ller cells were transplanted into subretinal space of the right eyes of 8 6-week-old RCS rats,and the left eyes received unactivated M(u|¨)ller cells as homotype control in 3 RCS rats and PBS as negtive control eyes in 3 RCS rats.The histologic assessment and electroretinogram(ERG) were carried out at the 1st,3rd,5th and 7th week after injection.Results Fluorescence-activated cell sorting(FACS) showed that the puritied M(u|¨)ller cells labeled by glutamine synthetase was above 96.07%,and 53.47% of cells presented positive fluorescene staining for nestin.Four to five layer of survival M(u|¨)ller cells were seen in the retina of transplantation zone and only one layer in non-transplantation zone under the light microscope.The numbers of survival photoreceptors in transplantation eyes of M(u|¨)ller cells were significantly increased than those of control eyes(P<0.01).The a-wave amplitudes of electrophysiology showed a statistically significant difference among the active cells injection group,unactive cells injection group and negative control group at 1,5 and 7 weeks after injection(P<0.01),and those of b wave were significantly different among the active cells injection group, unactive cells injection group and negative control group at 1,3,5 and 7 weeks after injection(P<0.01).Conclusion Subretinal transplantation of M(u|¨)ller glia with neural stem cell properties can effectivelly delay photoreceptor degeneration and functional deterioration time in RCS rats,which offer a new method of treating the retinal degenerative disease.