Short communicationPeripheral blood mononuclear cell responses to Dermatophagoides farinae in canine atopic dermatitis
Introduction
Atopic dermatitis is a well-recognised chronic inflammatory skin disease of humans (Rothe and Grant-Kels, 1996) and dogs (Scott et al., 1995). The relative risk of atopic dermatitis is strongly correlated to the house dust mite exposure (Cooper, 1994). Between 40 and 80% of human patients have house dust mite specific serum IgE and positive skin tests (Halbert et al., 1995), and approximately 60% of atopic dogs have positive skin tests to the house dust mite allergens (Sture et al., 1995). The major house dust mite species in temperate areas are Dermatophagoides farinae and Dermatophagoides pteronyssinus. D. pteronyssinus prefers more humid conditions than D. farinae and is the most common species in the UK (Thomas et al., 1998). Despite this, skin test reactions to D. farinae are more frequent than to D. pteronyssinus in atopic dogs in the UK (Sture et al., 1995).
Canine atopic dermatitis has been viewed as an IgE/mast cell-mediated disease (Scott et al., 1995). However, IgE production is dependent on the allergen-specific CD4+ TH-cells (Lydyard and Grossi, 1998) and infiltration of CD4+ and CD8+ lymphocytes is observed in lesional atopic skin in both dogs (Olivry et al., 1997) and humans (Leung, 2000). Several studies in humans have demonstrated PBMC proliferation to the crude Dermatophagoides extracts and purified allergens (reviewed in Leung, 2000). Despite this, investigation of PBMC responses in atopic dogs has been limited. One unpublished report suggested that PBMCs from atopic dogs had a proliferative response to the crude D. pteronyssinus extract and major allergens identified on Western blots (Shaw, 2000), but responses to D. farinae were not investigated.
The aim of this study, therefore, was to determine if allergen-specific T-cells were involved in the pathogenesis of canine atopic dermatitis by investigating PBMC responses to D. farinae in dogs with atopic dermatitis that were skin test positive to D. farinae, skin test negative to D. farinae and healthy dogs.
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Study population
Dogs with atopic dermatitis were recruited from the Dermatology Clinic at the University of Edinburgh Hospital for Small Animals. Diagnosis was based on compatible history and clinical signs, and exclusion of other causes of pruritus (Willemse, 1986, Nuttall et al., 1998). Coat brushings, skin scrapings and trial therapy were used to eliminate the possibility of ectoparasite infestation. All dogs underwent a 6 weeks, home cooked diet trial to eliminate the food intolerance. Seborrhoea,
Results and discussion
To our knowledge, this study documents for the first time the presence of circulating Dermatophagoides farinae specific T-cells in canine atopic dermatitis. PBMCs from D. farinae positive atopic dogs showed greater proliferation to all concentrations of the D. farinae extract than PBMCs from either D. farinae negative atopic dogs or healthy dogs (Fig. 1). Optimum proliferation was seen with 50 micrograms/ml D. farinae. At this concentration, there was significantly greater proliferation of
Acknowledgements
The authors are grateful for the help and assistance shown by Dr. K.L. Thoday, Mr. A.W. Carter and Mr. P. Fosythe of the Dermatology Service at the University of Edinburgh Hospital for Small Animals, Prof. H.R.P. Miller and Mrs. E. Thornton of the Department of Veterinary Clinical Studies and Dr. G.F. Hoyne, Dr. S.E.M. Howie, Dr. N. Savage and Ms. G. Hall of the Respiratory Medicine Unit, Immunobiology Group, MRC Centre for Inflammation Research. This study was funded by The Wellcome Trust.
References (30)
Atopic dermatitis: recent trends in pathogenesis and therapy
J. Invest. Dermatol.
(1994)- et al.
Proliferative responses of peripheral blood mononuclear cells from normal dogs with autoimmune haemolytic anaemia to red blood cell antigens
Vet. Immunol. Immunopathol.
(1997) - et al.
Atopic dermatitis: is it an allergic disease?
J. Am. Acad. Dermatol.
(1995) - et al.
Molecular mechanisms of CD8+ T cell-mediated delayed hypersensitivity: implications for allergies, asthma and autoimmunity
J. Allergy Clin. Immunol.
(1999) CD8+ T-cells in atopic disease
Curr. Op. Immunol.
(1998)- et al.
The lymphocyte stimulation test in veterinary immunology
Vet. Immunol. Immunopathol.
(1982) Atopic dermatitis: new insights and opportunities for therapeutic intervention
J. Allergy Clin. Immunol.
(2000)- et al.
Characterisation and cloning of a major high molecular weight house dust mite allergen (Der f15) for dogs
Vet. Immunol. Immunopathol.
(2001) The TH1/TH2 paradigm in allergy
Immunotechnology
(1998)- et al.
Revisiting the TH1/TH2 paradigm
Scand. J. Immunol.
(1999)
Functional and phenotypic analysis of in vitro stimulated canine peripheral blood mononuclear cells
Vet. Immunol. Immunopathol.
Atopic dermatitis: an update
J. Am. Acad. Dermatol.
Canine atopic dermatitis: the prevalence of positive intradermal skin tests at two sites in the north and south of Great Britain
Vet. Immunol. Immunopathol.
Biphasic response against aeroallergen in atopic dermatitis showing a switch from an initial TH2 response to a TH1 response in situ: an immunocytochemical study
J. Allergy Clin. Immunol.
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