Corneal Nerve Regeneration via MSC‐Derived EVs: Tissue Source and Culture Dimensionality Dictate miRNA Cargo and Therapeutic Efficacy

Why It Matters

Demonstrating that 3D‑cultured MSC‑EVs can more effectively restore corneal nerves provides a cell‑free therapeutic avenue for treating ocular injuries, potentially reducing reliance on invasive surgeries and improving visual outcomes.

Key Takeaways

• 3D culture boosts EV therapeutic potency.
• Corneal MSC EVs outperform bone marrow EVs.
• miRNA cargo varies by tissue source and dimensionality.
• 3D EVs enhance corneal nerve reinnervation in mice.
• Small RNA sequencing links EV miRNAs to ECM remodeling.

Pulse Analysis

The cornea’s dense network of sensory nerves is essential for epithelial health and clear vision, yet trauma, surgery, or degenerative disease can sever these fibers, leading to persistent defects and vision loss. Conventional treatments rely on topical drugs or surgical grafts, which often fail to fully restore neural function. In recent years, extracellular vesicles (EVs) secreted by mesenchymal stem cells have emerged as a promising cell‑free platform because they carry bioactive proteins, lipids, and RNAs that can modulate repair processes without the safety concerns of live cell transplantation.

To pinpoint the most potent EV formulation for corneal nerve repair, the study isolated vesicles from human corneal (Co‑MSC) and bone‑marrow (BM‑MSC) sources cultured under both two‑dimensional (2D) monolayers and three‑dimensional (3D) spheroids. Characterization by nanoparticle tracking, ExoView profiling, and Western blot confirmed comparable size distributions while revealing distinct surface marker patterns. Functional assays showed that all EVs encouraged neurite extension in primary trigeminal ganglion neurons, but 3D‑derived vesicles produced significantly longer outgrowths and accelerated reinnervation in a mouse corneal abrasion model. Small‑RNA sequencing demonstrated that 3D culture reshapes miRNA cargo, enriching pathways linked to neurotrophic signaling and extracellular‑matrix remodeling.

These findings have immediate relevance for biotech firms developing ocular therapeutics, as they highlight culture dimensionality as a scalable lever to boost EV efficacy without genetic manipulation. By selecting corneal‑derived MSCs and employing 3D bioreactors, manufacturers can generate vesicles enriched in miRNAs that simultaneously temper inflammation and promote axonal growth, addressing two critical barriers to nerve regeneration. The study also establishes a blueprint for rational EV design: integrate tissue‑specific cues and three‑dimensional culture to tailor cargo for targeted pathways. Future clinical trials will determine whether this cell‑free approach can replace or complement existing corneal nerve repair strategies.