title: Development of the fetal neural retina in vitro and in ectopic transplants in vivo.
abstract: Investigation of the developmental potential of immature tissues is important for novel approaches to human regenerative medicine. Development of the fetal neural retina has therefore been investigated in two experimental systems. Retinas were microsurgically isolated from 20-days-old rat fetuses and cultivated in vitro for 12 days or transplanted in vivo under the kidney capsule of adult males for as long as 6 months. Shedding of the photoreceptor outer segment which is a process occurring at the terminal stage of photoreceptor differentiation was observed in culture by transmission electron microscopy (TEM). In transplants, no photoreceptors were found although markers of terminal neural and glial differentiation (e,g. synaptophysin, chromogranin and glial fibrilary acidic protein--GFAP) along with the molecules involved in the process of differentiation (guidance molecule semaphorin IIIA and chondroitin sulfate proteoglycan) were expressed. Semaphorin was differentially expressed being absent from older transplants. Proliferating cell nuclear antigen and nestin (marker of undifferentiated neural cells) were still weakly expressed even in six-months-old transplants. We could conclude that in both our experimental systems fetal neural retina proceeded to differentiate further on. However, even in long-term ectopic transplants a small population of cells still retained the potential for proliferation and has not yet reached the stage of terminal differentiation.
authors.affiliation: Department of Biology, School of Medicine, University of Zagreb, Zagreb, Croatia.
authors.forename: Ana
authors.initials: A
authors.lastname: Katusić
authors.forename: Gordana
authors.initials: G
authors.lastname: Jurić-Lekić
authors.forename: Natasa
authors.initials: N
authors.lastname: Jovanov-Milosević
authors.forename: Maja
authors.initials: M
authors.lastname: Vlahović
authors.forename: Davor
authors.initials: D
authors.lastname: Jezek
authors.forename: Ljiljana
authors.initials: L
authors.lastname: Serman
authors.forename: Nino
authors.initials: N
authors.lastname: Sincić
authors.forename: Biljana
authors.initials: B
authors.lastname: Veljanovska
authors.forename: Floriana
authors.initials: F
authors.lastname: Bulić-Jakus
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D016332:Fetal Tissue Transplantation; D007668:Kidney; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D012160:Retina / Q000166:cytology / Q000196:embryology / Q000378:metabolism / Q000637:transplantation*; D040121:Semaphorin-3A / Q000378:metabolism; D016042:Transplantation, Heterotopic
chemical_list: D040121:Semaphorin-3A