Collagen Crosslinking for Keratoconus: Cellular Signaling Mechanisms

Area of Science:

• Ophthalmology
• Biomedical Engineering
• Cell Biology

Background:

• Collagen crosslinking (CXL) is a standard treatment for progressive keratoconus (KC).
• Patients with thin corneas (<400 µm) often do not qualify for CXL.
• The molecular mechanisms of CXL in KC remain incompletely understood.

Purpose of the Study:

• To investigate the in vitro molecular effects of CXL on normal and thin corneal stromal cells.
• To model CXL's impact on extracellular matrix (ECM) constructs derived from healthy (HCFs) and keratoconus (HKCs) cells.

Main Methods:

• Primary HCFs and HKCs were cultured to form 3D ECM constructs.
• CXL was applied to thin (week 2) and normal (week 4) ECM constructs.
• Protein analysis was performed to assess molecular changes, including Wnt signaling pathway components and specific biomarkers.

Main Results:

• CXL modulated Wnt signaling (Wnt7b, Wnt10a) and α-smooth muscle actin (SMA) expression.
• Prolactin-induced protein (PIP), a KC biomarker candidate, was upregulated by CXL in HKCs.
• CXL upregulated PGC-1 and downregulated SRC and Cyclin D1 in HKCs.

Conclusions:

• CXL influences key molecular pathways and biomarkers in corneal cells, including those relevant to KC.
• These findings offer insights into the complex mechanisms underlying CXL efficacy in KC.
• Further research is needed to fully elucidate factors affecting CXL outcomes.