Kidney Week

Abstract: FR-PO745

Heterozygous Inactivation of PKD1 in Miniature Pigs Induces Embryonic Cyst Formation and Progressive Autosomal Dominant Polycystic Kidney Disease (ADPKD)

Session Information

• Cystic Kidney Diseases: Clinical/Translational
  November 08, 2019 | Location: Exhibit Hall, Walter E. Washington Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Genetic Diseases of the Kidneys

• 1001 Genetic Diseases of the Kidneys: Cystic

Authors

• Daniel, Emily A., University of Kansas Medical Center, Kansas City, Kansas, United States

Emily A. Daniel,

• Raman, Archana, University of Pennsylvania, Philadelphia, Pennsylvania, United States

Archana Raman,

• Ward, Christopher J., KUMC, Kansas City, Kansas, United States

Christopher J. Ward,

• Reif, Gail, University of Kansas Medical Center, Kansas City, Kansas, United States

Gail Reif,

• Rogers, Christopher S., Exemplar Genetics, Coralville, Iowa, United States

Christopher S. Rogers,

• Fields, Timothy A., University of Kansas Medical Center, Kansas City, Kansas, United States

Timothy A. Fields,

• Rowe, Peter S. N., University of Kansas Medical Center, Kansas City, Kansas, United States

Peter S. N. Rowe,

• Calvet, James P., University of Kansas Medical Center, Kansas City, Kansas, United States

James P. Calvet,

• Wallace, Darren P., University of Kansas Medical Center, Kansas City, Kansas, United States

Darren P. Wallace,

Background

Murine models do not faithfully recapitulate important features of human ADPKD or its dominant inheritance. Gene editing and somatic cell nuclear transfer in large animals have provided superior models for human genetic disorders that have improved our understanding of disease mechanisms and the translational value of pre-clinical studies for novel therapies. Porcine anatomy, development, physiology, genetics and body size are like those of humans. We generated a new ADPKD model in the Yucatan miniature pig to monitor renal cyst formation in utero and postnatal PKD progression.

Methods

Gene targeting methods were used to insert a blasticidin cassette into intron 30 of PKD1, which resulted in a null allele, and somatic cell nuclear transfer to generate PKD1^+/- cloned pigs. Breeding colonies were established to generate PKD1^+/- and wildtype littermates. Kidneys were collected at embryonic days 30, 60, 90, newborn (~120 embryonic days) and 3, 6, 9 and 12 months postnatal to evaluate cyst development. Embryonic kidneys were imaged by micro-CT and larger kidneys were sectioned using a tissue slicer for measurement of cystic index. Thin tissue sections were stained with antibodies to AQP-2 to identify collecting ducts and PCNA, a marker of cell proliferation.

Results

Embryonic PKD1^+/- pig kidneys had sporadic cysts and cystic dilations that appeared to form in clusters, consistent with the proposed mechanism of early cyst development in human ADPKD. The number of cysts and total cystic area progressively increased after birth; however, changes in kidney weight relative to body weight were not significantly different between PKD1^+/- and wildtype pigs. Many, but not all, cysts stained positive for AQP-2, indicating the involvement of multiple segments of the nephron. There were increased PCNA-positive cells in cystic epithelia compared to non-cystic tissue in embryonic and adult PKD1^+/- kidneys.

Conclusion

Our results demonstrate that inactivation of one PKD1 allele induces renal cyst formation in utero and progressive ADPKD in a new porcine model ADPKD.

Funding

• NIDDK Support –