Paired pre- and post-transplant human immunoprofiling identifies an IFN-γ-JAK1 axis limiting stem-cell-derived RPE engraftment.

Abstract

Neovascular age-related macular degeneration is a major cause of irreversible blindness, and current therapies do not restore photoreceptors or retinal pigment epithelium (RPE). Human embryonic stem-cell-derived RPE (hESC-RPE) transplantation represents a potential regenerative strategy, but immune rejection limits durable engraftment. Here, we combine immune profiling of blood, aqueous humor, and retinal tissue with allogeneic co-cultures and humanized models to define determinants of graft vulnerability and assess a graft-directed intervention. We identify a Th1-skewed, IFN-γ-rich immune milieu across the circulation and eye and show that IFN-γ-JAK1 signaling promotes an immunogenic state in hESC-RPE, marked by increased HLA expression and antigen presentation features. Brief ex vivo conditioning with ruxolitinib attenuates this response while preserving epithelial properties. In humanized retinal degeneration models, conditioned grafts show reduced T/natural killer (NK)-cell infiltration, prolonged survival, and improved visual function without chronic systemic immunosuppression, supporting ex vivo JAK inhibition as a feasible adjunct to RPE cell therapy.