EXPERIMENTALLY INDUCED DISEASE An Experimental Dermal Oedema Model for Apx Toxins of Actinobacillus pleuropneumoniae

Soutter, Francesca; Priestnall, Simon L; Catchpole, Brian; Rycroft, Andrew N

Abstract

In-vivo models of Actinobacillus pleuropneumoniae (App) infection in pigs are required for the development of vaccines and investigations of pathogenicity. Existing models cause severe respiratory disease with pulmonary oedema, dyspnoea and severe thoracic pain, and careful monitoring and early intervention with euthanasia is, therefore, needed to avoid unnecessary suffering in experimental animals. As a potential replacement for the existing respiratory infection model, an in-vivo protocol was evaluated using intradermal or subcutaneous injection of different App strains and Apx toxins into the abdominal skin of pigs. High concentrations of serovar 1 and serovar 10 App induced diffuse visible dermal oedema and inflammation. Injection of Apx toxins alone did not adequately produce macroscopic lesions, although an influx of inflammatory cells was seen on histopa-thology. ApxI-producing strains of App induced more inflammation than ApxII-and ApxIII-producing strains. Induction of skin lesions by injection of App or Apx toxins was not sufficiently repeatable or discrete for a robust experimental model that could be used for assessment of novel interventions.

Citation

Soutter, F., Priestnall, S. L., Catchpole, B., & Rycroft, A. N. (2022). EXPERIMENTALLY INDUCED DISEASE An Experimental Dermal Oedema Model for Apx Toxins of Actinobacillus pleuropneumoniae. Journal of Comparative Pathology, https://doi.org/10.1016/j.jcpa.2022.04.004

• Journal Article Type: Article
• Acceptance Date: Apr 27, 2022
• Online Publication Date: May 30, 2022
• Publication Date: May 30, 2022
• Deposit Date: Jun 1, 2022
• Publicly Available Date: Jun 21, 2022
• Journal: Journal of Comparative Pathology
• Print ISSN: 0021-9975
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• DOI: https://doi.org/10.1016/j.jcpa.2022.04.004
• Keywords: Actinobacillus pleuropneumoniae; animal model; skin; toxin