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001-es BibID:BIBFORM037061
Első szerző:Froen, Rebecca C.
Cím:Pigment epithelial cells isolated from human peripheral iridectomies have limited properties of retinal stem cells / Froen R. C., Johnsen E. O., Petrovski G., Berényi E., Facskó A., Berta A., Nicolaissen B., Moe M. C.
Dátum:2011
ISSN:1755-375X
Megjegyzések:PURPOSE: The identification of cells with properties of retinal progenitor cells (RPCs) in the adult human ciliary margin (CM) prompted a number of studies of their proliferative and differentiation potential. One of the remaining challenges is to find a feasible method of isolating RPCs from the patient's eye. In the human CM, only the iris pigment epithelium (IPE) is easily obtained by a minimally invasive procedure. In the light of recent studies questioning the existence of RPCs in the adult mammalian CM, we wanted to assess the potential of the adult human IPE as source of RPCs. METHODS: The IPE were isolated from peripheral iridectomies during glaucoma surgery, and IPE and ciliary body (CB) epithelium were also isolated from post-mortem tissue. Cells were cultivated in sphere-promoting conditions or as monolayers. Whole-tissue samples, undifferentiated and differentiated cells were studied by immunocytochemistry, RT-PCR and transmission electron microscopy. RESULTS: The adult human IPE, like the CB, expressed markers of RPCs such as Pax6, Sox2 and Nestin in vivo. Both sphere-promoting and monolayer cultures preserved this phenotype. However, both IPE/CB cultures expressed markers of differentiated epithelial cells such as Claudin, microphtalmia-associated transcription factor (MITF) and Cytokeratin-19. Ultrastructurally, IPE spheres displayed epithelial-like junctions and contained mature melanosomes. After induced differentiation, IPE-derived cells showed only partial neuronal differentiation expressing beta-III-tubulin, Map-2 and Rhodopsin, whereas no mature glial markers were found. CONCLUSION: Proliferative cells with some properties of RPCs can be isolated from the adult human IPE by peripheral iridectomies. Yet, many cells retain properties of differentiated epithelial cells and lack central properties of somatic stem cells.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Acta Ophthalmologica. - 89 : 8 (2011), p. 635-644. -
További szerzők:Johnsen, Erik O. Petrovski, Goran (1975-) (orvos) Berényi Erika Facskó Andrea (1953-) (szemész) Berta András (1955-) (szemész, gyermekszemész) Nicolaissen, Bjorn Moe, Morten C.
Internet cím:Intézményi repozitóriumban (DEA) tárolt változat
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001-es BibID:BIBFORM037065
Első szerző:Johnsen, Erik O.
Cím:Activation of neural progenitor cells in human eyes with proliferative vitreoretinopathy / Johnsen E. O., Froen R. C., Albert R., Omdal B. K., Sarang Z., Berta A., Nicolaissen B., Petrovski G., Moe M. C.
Dátum:2012
ISSN:0014-4835
Megjegyzések:In addition to the ability for self-renewal and functional differentiation, neural stem/progenitor cells (NSCs) can respond to CNS injuries by targeted migration. In lower vertebrates, retinal injury is known to activate NSCs in the ciliary marginal zone (CMZ). Cells expressing markers of NSCs are also present in the ciliary body epithelium (CE) and in Müller glia in the peripheral retina (PR) of the adult human eye. However, these cells seem to be quiescent in the adult human eye and recent reports have shown that CE cells have limited properties of NSCs. In order to further clarify whether NSCs exist in the adult human eye, we tested whether NSC-like cells could be activated in eyes with proliferative vitreoretinopathy (PVR). The PR and CE were studied for NSC-associated markers in human enucleated control eyes and eyes with confirmed PVR, as well as in a mouse model of PVR. Furthermore, cells isolated from vitreous samples obtained during vitrectomies for retinal detachment were directly fixed or cultured in a stem cell-promoting medium and compared to cells cultured from the post-mortem retina and CE. In situ characterization of the normal eyes revealed robust expression of markers present in NSCs (Nestin, Sox2, Pax6) only around peripheral cysts of the proximal pars plana region and the PR, the latter population also staining for the glial marker GFAP. Although there were higher numbers of dividing cells in the CE of PVR eyes than in controls, we did not detect NSC-associated markers in the CE except around the proximal pars plana cysts. In the mice PVR eyes, Nestin activation was also found in the CE. In human PVR eyes, proliferation of both non-glial and glial cells co-staining NSC-associated markers was evident around the ora serrata region. Spheres formed in 7/10 vitreous samples from patients with PVR compared to 2/15 samples from patients with no known PVR, and expressed glial - and NSC-associated markers both after direct fixation and repetitive passages. In conclusion, the adult human eye may harbor two different populations of neuroepithelial stem/progenitor cells; a non-glial population located in the proximal pars plana around peripheral cysts in addition to a population with Müller glia characteristics. Yet, we only found that the glial population was able to respond to retinal injury by targeted migration into the vitreous.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Experimental Eye Research. - 98 (2012), p. 28-36. -
További szerzők:Froen, Rebecca C. Albert Réka (1986-) Omdal, Bente K. Sarang Zsolt (1976-) (mikrobiológus) Berta András (1955-) (szemész, gyermekszemész) Nicolaissen, Bjorn Petrovski, Goran (1975-) (orvos) Moe, Morten C.
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DOI
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