Is Keratoconus an Inflammatory Disease? The Implication of Inflammatory Pathways

ABSTRACT

Purpose

Keratoconus is considered a non-inflammatory condition. Recently however, increased proinflammatory cytokines have been detected in the tears of keratoconic patients and clinical and immunohistochemical observations reported infiltration of matured dendritic cells and leukocytes. Our laboratory utilized cytokine antibody arrays to elucidate the inflammatory aspects of keratoconus.

Methods

Protein was extracted from 42 corneal buttons (14 keratoconic and 28 non-keratoconic) and incubated with cytokine antibody arrays scanning 120 cytokines. Mann Whitney U test with a p-value of <0.05 was considered significant.

Results

Pathways for wound healing, neuroprotection, angiogenesis, and inflammation were activated in keratoconic samples with 23 cytokines showing significant elevation. Fifteen were expressed only in keratoconus with 8 cytokines elevated 1.7–42-fold.

Conclusion

This study identified elevated inflammatory pathways covering immune responses in keratoconus. Our results support the evidence for inflammatory pathway activation in keratoconus and a possible redefinition of keratoconus as a chronic inflammatory corneal disease.

KEYWORDS:

• Keratoconus
• inflammation
• cytokines
• corneae
• human

Acknowledgments

The authors want to thank both the people who donated their tissues and their families for their selfless contribution to this research.

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper

Additional information

Funding

This work was supported by the Save Sight Society of New Zealand (2006).