title: Characterization and survival of long-term implants of human retinal pigment epithelial cells attached to gelatin microcarriers in a model of Parkinson disease.
abstract: Previous studies have demonstrated that the intrastriatal implantation of human retinal pigment epithelial cells attached to gelatin microcarriers (hRPE-GM) ameliorates behavioral deficits in animal models of Parkinson disease. However, there are only sparse data on cell survival in the host. In this study, we characterized a variety of retinal pigment epithelial (RPE)-specific markers in vitro and used these markers to investigate the long-term survival of hRPE-GM implants. Sprague-Dawley rats (n = 22) were unilaterally lesioned with 6-hydroxydopamine (6-OHDA) and implanted with hRPE-GM without immunosuppression. Rats were euthanized at 48 hours, 7 days, 4 weeks, and 5 months postimplant and immunohistochemically processed using the following antibodies: 1) human-specific nuclear mitotic apparatus protein (NuMA-Ab2), 2) epithelial-specific extracellular matrix metalloproteinase inducer (EMMPRIN), 3) RPE cell-specific RPE65, and the inflammation markers 4) glial fibrillary acidic protein and 5) ED1 (rat CD68). Our analysis revealed NuMA-, EMMPRIN-, and RPE65-immunoreactive cells at different times postimplant. The morphologic features of hRPE cell implants (at 48 hours and 5 months) were confirmed by electron microscopy. Furthermore, despite evidence of chronic inflammation at the later time point, there is an appreciable number of surviving hRPE cells. This study suggests that hRPE-GM implants can survive in the absence of immunosuppression and can be potentially used as an alternative for treating Parkinson disease.
authors.affiliation: Department of Medicine/Neurology and the Pacific Parkinson's Research Centre, University of British Columbia, 2221 Wesbrook Mall, Vancouver, BC, Canada. joflores@interchange.ubc.ca
authors.forename: Joseph
authors.initials: J
authors.lastname: Flores
authors.forename: Ivan L
authors.initials: IL
authors.lastname: Cepeda
authors.forename: Michael L
authors.initials: ML
authors.lastname: Cornfeldt
authors.forename: John R
authors.initials: JR
authors.lastname: O'Kusky
authors.forename: Doris J
authors.initials: DJ
authors.lastname: Doudet
mesh_terms: D000818:Animals; D002470:Cell Survival; D017690:Cell Transplantation / Q000379:methods*; D003342:Corpus Striatum / Q000473:pathology* / Q000503:physiopathology / Q000601:surgery; D004195:Disease Models, Animal; D005780:Gelatin / Q000627:therapeutic use; D006801:Humans; D008297:Male; D046529:Microscopy, Electron, Transmission / Q000379:methods; D008863:Microspheres; D009419:Nerve Tissue Proteins / Q000378:metabolism; D010300:Parkinson Disease / Q000209:etiology / Q000503:physiopathology / Q000601:surgery*; D010857:Pigment Epithelium of Eye / Q000502:physiology / Q000637:transplantation / Q000648:ultrastructure; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D014183:Transplantation, Heterologous / Q000379:methods*
chemical_list: D009419:Nerve Tissue Proteins; D005780:Gelatin