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Updated: Jul 18, 2026
Non-invasive In Vivo Fluorescence Optical Imaging of Inflammatory MMP Activity Using an Activatable Fluorescent Imaging Agent
Published on: May 8, 2017
Matrix metalloproteinase mRNA expression in canine anal furunculosis lesions
A K House1, B Catchpole, S P Gregory
1Department of Veterinary Clinical Sciences, Royal Veterinary College, University of London, Hawkshead Lane, North Mymms, Hertfordshire AL9 7TA, United Kingdom. ahouse@rvc.ac.uk
Abstract:
Although the aetiology of anal furunculosis (AF) in dogs is poorly understood, there is evidence for an underlying immune dysfunction. This is illustrated by the presence of a T helper type 1 cytokine mRNA profile in AF lesions and the clinical response to ciclosporin therapy. Expression of MMPs 2, 9 and 13 were evaluated in AF lesional biopsies by real-time quantitative RT-PCR. There was significantly increased expression of both MMP-9 and MMP-13 mRNA in AF biopsies compared to controls (p<0.001) but no significant difference in MMP-2 mRNA expression. Since MMP-9 and MMP-13 are primarily produced by macrophages, these data suggest that ulceration could be the result of aberrant activation of this cell type in the tissues. It is feasible that such pathological macrophage activity occurs in response to interferon-gamma secreted by T helper type 1 cells. This could explain why the lesions resolve following treatment with the immunosuppressive drug ciclosporin.
Insights
Anal furunculosis (AF) in dogs involves immune dysfunction, with increased MMP-9 and MMP-13 in lesions. This suggests pathological macrophage activity, potentially explaining AF
Area of Science:
- Veterinary Immunology
- Canine Dermatology
Background:
- Anal furunculosis (AF) in dogs is poorly understood, but immune dysfunction is suspected.
- A T helper type 1 (Th1) cytokine mRNA profile is observed in AF lesions.
- Clinical improvement with ciclosporin suggests an immune-mediated component.
Purpose of the Study:
- To investigate the expression of matrix metalloproteinases (MMPs) in canine AF lesions.
- To explore the potential role of macrophages and Th1 cytokines in AF pathogenesis.
Main Methods:
- Real-time quantitative RT-PCR was used to evaluate MMP-2, MMP-9, and MMP-13 mRNA expression in AF biopsies.
- Biopsies from dogs with AF were compared to control samples.
Main Results:
- Significantly increased MMP-9 and MMP-13 mRNA expression was found in AF biopsies compared to controls (p<0.001).
- No significant difference in MMP-2 mRNA expression was observed between groups.
- Elevated MMPs suggest macrophage involvement in tissue ulceration.
Conclusions:
- Aberrant activation of macrophages, possibly stimulated by Th1-secreted interferon-gamma, may cause ulceration in AF.
- These findings support the rationale for using immunosuppressive therapy like ciclosporin in treating AF.
