Optimizing the Survival of hESC-Derived RPE Cells Using Layer-by-Layer in Vivo Self-Assembly

Abstract

Retinal pigment epithelial (RPE) cell transplants have served as a cell therapy for treating retinal degenerative diseases. However, how to optimize the survival and engraftment of RPE cells is a great challenge. Here, we established human embryonic stem cells-derived RPE cells, then used layer-by-layer (LbL) self-assembly to coat RPE cells. Cells were assessed for cell survival, immunogenicity, and function in vitro and in vivo. LbL-RPE cell cultures, IFN-γ ELISIA, a mixed lymphocyte reaction assay, and a T-cell rejection assay indicated that a LbL coating optimized survival, function, and immunogenicity of RPE cells. LbL-RPE cell transplants into Royal Collage of Surgeons (RCS) rats showed in vivo self-assembly to optimize cells engraftment, and decreased immunogenicity as judged by the lack of a robust invasion of the transplant area by Iba1⁺ cells, CD3⁺ T cells, or MHC class II⁺ cells compared to untreated RPE cell transplants (immunosuppression was not used during the 5-wk study). Electroretinogram recordings also showed higher B wave amplitudes in RCS rats with LbL-RPE cell transplants. We demonstrate transplanted LbL in vivo self-assembly RPE cells enhance cell survival and engraftment optimizing immunogenicity and visual function. Thus, LbL in vivo self-assembly may be suite for treating retinal degenerative disease.