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Non-pigmented ciliary epithelium derived extracellular vesicles uptake mechanism by the trabecular meshwork
Saray Tabak1, Uzi Hadad2, Sofia Schreiber-Avissar1
1Clinical Biochemistry and Pharmacology Department, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
Summary
Extracellular vesicles (EVs) from the Non-Pigmented Ciliary Epithelium deliver signals to Trabecular Meshwork cells, influencing Wnt-TGFβ2 signaling via endocytosis-dependent pathways involving surface proteins.
Area of Science:
- Ophthalmology
- Cell Biology
- Biotechnology
Background:
- Extracellular vesicles (EVs) in aqueous humor act as signaling mediators in glaucoma.
- EVs are promising for drug delivery and bio-therapeutics due to their intercellular transport capabilities.
- The precise signaling pathways of EVs in the ocular drainage system remain unclear.
Purpose of the Study:
- To investigate the internalization mechanisms of Non-Pigmented Ciliary Epithelium (NPCE)-derived EVs in Trabecular Meshwork (TM) cells.
- To elucidate how NPCE-derived EVs deliver signals to TM cells within the ocular drainage system.
Main Methods:
- EVs were isolated from NPCE and characterized for size and concentration.
- Internalization studies involved Proteinase-K treatment to remove surface proteins and examination of energy-dependent uptake.
- Uptake inhibitors for endocytosis and phagocytosis, alongside Wnt-TGFβ2 signaling analysis, were employed.
Main Results:
- NPCE EVs significantly decreased p-GSK3β and β-catenin levels in TM cells.
- Reduced uptake of Proteinase-K-treated EVs correlated with attenuated Wnt-TGFβ2 protein expression.
- Endocytosis inhibitors abolished the decrease in Wnt-TGFβ2 proteins, while phagocytosis inhibitors caused partial inhibition.
Conclusions:
- NPCE EVs mediate Wnt-TGFβ2 signaling in TM cells through their surface proteins.
- The process is active and primarily dependent on endocytosis-driven routes.
- Understanding these mechanisms is crucial for developing EV-based glaucoma therapies.
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