Kidney Week

Abstract: SA-PO350

Deletion of the Mitochondrial Complex-IV Co-Factor Heme A:Farnesyltransferase Causes FSGS and Interferon Response

Session Information

• Glomerular Diseases: Immunology and Inflammation - III
  October 27, 2018 | Location: Exhibit Hall, San Diego Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Glomerular Diseases

• 1202 Glomerular Diseases: Immunology and Inflammation

Authors

• Baek, Jea-Hyun, Biogen Inc., Cambridge, Massachusetts, United States

Jea-Hyun Baek,

• Gomez, Ivan G., Biogen Inc., Cambridge, Massachusetts, United States

Ivan G. Gomez,

• Wada, Yukihiro, Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan

Yukihiro Wada,

• Roach, Allie M., Biogen Inc., Cambridge, Massachusetts, United States

Allie M. Roach,

• Mahad, Don J., University of Edinburgh, Edinburgh, United Kingdom

Don J. Mahad,

• Duffield, Jeremy Stuart, Biogen Inc., Cambridge, Massachusetts, United States

Jeremy Stuart Duffield,

Background

Mutations in mitochondrial DNA as well as in nuclear-encoded mitochondrial proteins have been reported to cause tubulointerstitial kidney diseases and focal segmental glomerulosclerosis (FSGS). More recently, genes and pathways affecting mitochondrial turnover and permeability have been implicated in adult onset FSGS. Furthermore, dysfunctioning mitochondria may be capable of engaging intracellular innate immune sensing pathways.

Methods

To determine the impact of mitochondrial dysfunction in FSGS and secondary innate immune responses, we generated Cre/loxP transgenic mice to create loss-of-function deletion mutation of the Complex IV assembly co-factor heme A:farnesyltransferase (COX10) restricted to cells of the developing nephrons.

Results

These mice develop severe, early onset FSGS with innate immune activation, and die prematurely with kidney failure. Mutant kidneys showed loss of glomerular and tubular epithelial function, epithelial apoptosis and in addition a marked interferon response. In vitro modeling of Cox10 deletion in primary kidney epithelium compromises oxygen consumption, ATP generation, and induces oxidative stress. In addition, loss of Cox10 triggers a selective interferon response, which may be caused by the leak of mitochondrial DNA into the cytosol activating the intracellular DNA sensor, STING.

Conclusion

This new animal model provides a mechanism to study mitochondrial dysfunction in vivo and demonstrates a direct link between mitochondrial dysfunction and intracellular innate immune response.

Funding

• Other NIH Support – Biogen