Single cell transcriptomic analysis of proliferative diabetic retinopathy fibrovascular membranes reveals AEBP1 as fibrogenesis modulator.
The management of preretinal fibrovascular membranes, a devastating complication of advanced diabetic retinopathy (DR), remains challenging. We characterized the molecular profile of cell populations in these fibrovascular membranes to identify new therapeutic targets. Preretinal fibrovascular membranes were surgically removed from patients and submitted for single cell RNA (scRNA) sequencing. Differential gene expression was implemented to define the transcriptomic profile of these cells and revealed the presence of endothelial, inflammatory, and stromal cells. Endothelial cell re-clustering identified subclusters characterized by non-canonical trascriptomic profile, and active angiogenesis. Deeper investigation of the inflammatory cells showed a subcluster of macrophages expressing pro-angiogenic cytokines, presumably contributing to angiogenesis. The stromal cell cluster included a pericyte-myofibroblast transdifferentiating subcluster, indicating the involvement of pericytes in fibrogenesis. Differentially expressed gene analysis showed that Adipocyte Enhancer-binding Protein 1, AEBP1, was significantly upregulated in myofibroblast clusters, suggesting that this molecule may have a potential role in transformation. Cell culture experiments with human retinal pericytes (HRP) in high glucose condition confirmed the molecular transformation of pericytes towards myofibroblastic lineage. siAEBP1 transfection in HRP reduced the expression of profibrotic markers in high glucose.  In conclusion, AEBP1 signaling modulates pericyte-myofibroblast transformation, suggesting that targeting AEBP1 could prevent scar tissue formation in advanced DR. Overall design: Preretinal fibrovascular membranes were surgically removed from patients and submitted for single cell RNA (scRNA) sequencing.