Abstract
Purpose: :
The human RPE is a polar organized, highly specialized epithelium. To maintain its functions multiple interactions among the RPE–cells and the neighboring tissues are necessary and play an important role in the pathology of innummerous diseases of the posterior segment. This study aims to investigate whether a perfusion tissue culture of the human retina–RPE–choroidea complex could be a suitable model to study these diseases in vitro.
Methods: :
Human retina–RPE–choroidea–tissue was isolated from patients after enucleation because of various reasons. Written consent was obtained prior to surgery. After removal of the anterior segment and the vitreous the choroidea–RPE–retina complex was separated from the sclera and transferred immediately into a gradient tissue culture chamber (Minucells&Minutissue, Bad Abbach, Germany) kept at 37°C and perfused with DMEM and Ham's F12 1:1, supplemented with 10% human serum, 25mM HEPES and 1% penicillin–streptomycin, 110mg/l sodium–pyruvat for five days at a perfusion rate of 3ml/h on both the apical and the basal segment. Structural preservation and morphology of the cultured tissue were compared to findings at baseline by light microscopy.
Results: :
At baseline a regular histology of the retina–RPE–choroidea complex was noted. After cultivation for five days no structural alterations of the choroidea were noted. RPE–cells were vital, showing the typical polar organisation with nuclei in the basal and melanosomes in the apical cell compartment. Directed to the subretinal space the RPE–cells were rounded and appeared slightly swollen with intact cell–to–cell contacts. Except minor alterations at the inner and outer photoreceptor segments the architecture of the retinal structures was well preserved.
Conclusions: :
Overall, after cultivation for five days the morphological integrity of the human retina–RPE–choroidea complex was well preserved. Organotypic differentiation is maintained by the existence of connections with the neighboring tissue and specialized cell–to–cell contacts. Thus, human retina–RPE–choroidea may be an useful in vitro model to investigate diseases of the posterior segment, i. e. AMD.
Keywords: retinal pigment epithelium • retinal culture • age-related macular degeneration