Generation of a three-dimensional retinal-like structure using a laminin-111-modified alginate layer

Area of Science:

• Ophthalmology
• Developmental Biology
• Stem Cell Biology

Background:

• Increasing prevalence of incurable visual impairments necessitates novel therapeutic strategies.
• Understanding retinal development is crucial for regenerative medicine approaches.
• Current methods for retinal progenitor cell differentiation require optimization.

Purpose of the Study:

• To develop a 3D co-culture system for retinal progenitor cells (RPCs) with retinal pigment epithelium (RPE) cells.
• To mimic the in vivo retinal environment to promote RPC differentiation.
• To investigate the role of RPE cells in supporting RPC development.

Main Methods:

• Utilized a 3D culture system with modified alginate substrate for human embryonic stem cell-derived RPCs on an RPE layer.
• Analyzed RPC characteristics at RNA and protein levels under hypoxic and normoxic conditions.
• Examined 3D retinal-like structures using H&E staining and Matrigel supplementation.

Main Results:

• Hypoxic conditions maintained naïve RPC characteristics, with higher expression of RAX, LHX2, and PAX6.
• Matrigel addition supported RPE survival, simulating the subretinal space.
• RPCs in the 3D co-culture exhibited enhanced differentiation into neural tube-like structures and higher photoreceptor marker expression.

Conclusions:

• The 3D co-culture system effectively promotes retinal progenitor cell differentiation.
• RPE-secreted factors appear to induce neural tube-like structure formation in RPCs.
• This model offers a promising platform for studying retinal development and advancing preclinical/clinical applications for vision restoration.