Purchase this article with an account.
Sunghee Estelle Park, Wenli Yang, Dwight Stambolian, Dan Dongeun Huh; Microengineered model of the RPE-choroid complex for the study of AMD. Invest. Ophthalmol. Vis. Sci. 2019;60(9):1340.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Studying the pathophysiology of AMD in vitro requires the ability to model the RPE-choroid complex in the outer layer of the retina (Fig. 1A). Here we present a unique bioengineering approach based on microphysiological culture of primary and iPSC-derived human retinal cells to mimic this important tissue-tissue interface.
Our model was constructed in a PDMS device for co-culture of RPEs and perfusable blood vessels (Figs. 1B,C). An ECM hydrogel scaffold containing human vascular endothelial cells and fibroblasts was created in the lower compartment of the device to induce self-assembly of endothelial cells to 3D vascular networks. Primary human RPEs or iPS-derived RPEs were cultured in the upper compartment to form a confluent epithelial monolayer. Following P values were used: *P < 0.05, **P < 0.01, and ***P < 0.001 (n = 3).
The endothelial cells organized themselves into perfusable blood vessels (Figs. 1D-F). After 21 days of culture, the engineered vessels induced significant increase in the expression of ZO-1, RPE pigmentation and the production of basal deposits and basement membrane protein (Figs. 1G-J).We then used RPEs differentiated from iPSCs with the goal of developing a pathophysiological model of AMD. Patient cells spontaneously showed hypopigmentation and downregulation of RPE65 expression (Figs. 2A-D). The number and size of drusen-like deposits were significantly increased in comparison to the control group established using normal cells (Fig. 2E). In addition, the patient-derived cells showed increased barrier permeability (Fig. 2H). Finally, decreased phagocytic activities and increased VEGF and PEDF secretions were observed in AMD (Figs. 2I-K).
The microengineered 3D cell culture model presented in this study demonstrates our ability to model the RPE-choroid complex. This system may serve as a robust research platform for studying the development and progression of AMD.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.
(A) RPE-choroid complex. (B,C) Primary human RPEs with blood vessels in the device. (D-F) Perfusability of the vessels. (G-J) Tight junction, pigmentation, drusen and basement membrane protein productions. Scale bars: (C,D,F-I) = 50 µm, (E) = 100 µm.
(A) Dark granules in iPS-RPEs. (B,C) RPE65 and ZO-1 expressions. (D-G) Pigmentation, laminin production and drusen formation. (H) Barrier function. (I,I’) Phagocytosis. (J,K) VEGF and PEDF concentrations. Scale bars: (A,C-G) = 50 µm, (B) = 25 µm, (I) = 10 µm.
This PDF is available to Subscribers Only