Stromal fibroblast-bone marrow-derived cell interactions: implications for myofibroblast development in the cornea

Area of Science:

• Cell Biology
• Tissue Engineering
• Ophthalmology

Background:

• Myofibroblasts are crucial for tissue repair and remodeling.
• Understanding the cellular origins and regulation of myofibroblasts is vital for regenerative medicine.
• Corneal stromal fibroblasts and bone marrow-derived cells are potential precursors for myofibroblast generation.

Purpose of the Study:

• To investigate if co-culturing mouse corneal stromal fibroblasts and bone marrow-derived cells enhances myofibroblast generation.
• To determine whether these interactions are mediated by paracrine (soluble factors) or juxtacrine (direct cell contact) mechanisms.
• To identify the role of transforming growth factor-beta (TGF-β) in this process.

Main Methods:

• Co-culture of GFP-labeled mouse corneal stromal fibroblasts and bone marrow-derived cells using Primaria plates (juxtacrine) and Transwell System plates (paracrine).
• Quantification of alpha-smooth muscle actin (α-SMA)-positive myofibroblasts.
• Inhibition studies using anti-TGF-β neutralizing antibody (a-LAP) and TGF-β receptor kinase inhibitor (LY-364947).

Main Results:

• Co-culture significantly increased myofibroblast generation compared to single-cell cultures (p<0.001).
• Juxtacrine interactions led to a higher percentage of myofibroblast generation than paracrine interactions.
• Both corneal fibroblasts and bone marrow-derived cells could differentiate into myofibroblasts.
• TGF-β inhibition significantly reduced myofibroblast generation, confirming its role.

Conclusions:

• Mouse corneal stromal fibroblast and bone marrow-derived cell interactions augment myofibroblast generation.
• Juxtacrine signaling is a more potent mechanism than paracrine signaling in this context.
• TGF-β acts as a paracrine mediator regulating myofibroblast differentiation from both cell types.