Consistent detection of bovine papillomavirus in lesions, intact skin and peripheral blood mononuclear cells of horses affected by hoof canker

Equine Vet J. 2011 Mar;43(2):202-9. doi: 10.1111/j.2042-3306.2010.00147.x.


Reasons for performing the study: Equine hoof canker is a chronic proliferative pododermatitis of as yet unknown aetiology. Like equine sarcoid disease, canker is a therapy-resistant disorder characterised by hyperkeratosis, acanthosis and a marked tendency to recur.

Hypothesis: There is an association of sarcoid-inducing bovine papillomaviruses of types 1 and 2 (BPV-1, BPV-2) with hoof canker disease.

Methods: Using PCR-based techniques, we assessed canker tissue, intact skin and/or peripheral blood mononuclear cells (PBMCs) of 25 canker-affected horses for the presence of sarcoid-associated BPV-1 and -2.

Results: Conventional PCR revealed BPV-1/-2 DNA in 24/24 canker, 12/13 skin and 10/11 PBMC DNA isolates. Using inverse PCR, full-length BPV episomes were detected in 1/5 canker specimens. Sequencing of viral early and late genes amplified from canker, intact skin and PBMC DNA of 2 cases revealed an overall identity of 98% to BPV-1. Viral DNA loads amounted to ≤16 copies per cell in canker tissue and intact skin, and to ≤0.35 copies per PBMC, as determined by quantitative PCR. Using RT-PCR, the viral major oncogene E5 was shown to be transcribed in 2/4 canker tissue specimens and 5/7 PBMC isolates. Immunocapture PCR from 7 canker and 6 skin extract supernatants revealed capsomere-associated viral DNA in one canker and one skin sample. Hoof tissue, skin and PBMCs collected from 13 individuals with no signs of canker or BPV-related malignancies scored negative throughout the experiments.

Conclusion: These findings suggest that the observed presence of BPV-1/-2 in canker-affected horses is not coincidental but indicative of an active contribution to hoof canker disease.

Potential relevance: The use of antivirals and/or immune modulators may help improving canker therapy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Bovine papillomavirus 1 / isolation & purification*
  • DNA, Viral / isolation & purification
  • Foot Diseases / veterinary*
  • Foot Diseases / virology
  • Hoof and Claw / virology*
  • Horse Diseases / virology*
  • Horses
  • Leukocytes, Mononuclear / virology
  • Papillomavirus Infections / veterinary*
  • Papillomavirus Infections / virology
  • Skin / virology*
  • Viral Proteins / chemistry
  • Viral Proteins / isolation & purification


  • DNA, Viral
  • Viral Proteins