The Translocation of an Autologous Free RPE and Choroid Graft: An Organ Culture

Abstract

Abstract: : Purpose:Preliminary clinical results in patients with ARMD treated with the translocation of an autologous full–thickness graft consisting of retinal pigment epithelium (RPE), Bruch’s membrane, choriocapillaris and choroid are promising. An animal model with pigs showed a revascularized and viable graft after translocation. This study aims to investigate whether a perfusion organ culture is a suitable model to study the revascularization of this graft. Methods: RPE and underlying choroid were prepared from the sclera in freshly enucleated porcine eyes. After damaging the recipient RPE and Bruch’s membrane, we positioned an autologous RPE–choroid–graft on top of this damaged area. We than secured the recipient with translocated graft in a holding ring (Minusheet©), which was placed in a two–compartment tissue culture container (Minucell & Minutissue). We provide a continuous perfusion with separate media at the superior and inferior side of the specimen. We kept the tissue 3 to 5 days in culture. Tissue sections were evaluated after histo– and immunohistochemical staining. Results: The recipient and graft showed normal organotypic features for 4 days in perfusion culture. Proliferating RPE–cells from the recipient onto the patch could be seen. The 5 specimens did not show vessels infiltrating from the recipient into the graft. Conclusions: As active angiogenesis with revascularization of the graft was not observed, these preliminary results can not confirm if this perfusion organ culture model is suitable to study the revascularization process of the graft. Other processes, like behaviour of the recipients Bruch’s membrane underneath the graft and proliferation of RPE cells, can be studied in the organotypic normal specimen.

Keywords: age-related macular degeneration • transplantation • pathology: experimental