Abstract
Objective—To investigate the role of Felis domesticus allergen I (Feld I) in the pathogenesis of eosinophilic granuloma complex (EGC) in cats.
Animals—7 healthy cats and 6 cats with EGC.
Procedure—Epidermis was removed from 4 areas. Rubber stoppers filled with Feld I, saline (0.9% NaCl) solution, and PBS solution were glued to the skin lesions and removed 48 hours later. Fluid within each stopper was collected. Biopsy specimens were obtained at each site, snap frozen, and stored at –70 C. Total and differential numbers of cells in fluid were counted. Biopsy specimens were stained by use of monoclonal antibodies against feline CD4, CD8 and CD3. Data were analyzed by use of multivariate repeated-measures analysis.
Results—Healthy cats had a significant increase in number of CD3+ cells, compared with number of CD4+ and CD8+ cells, and Feld I caused a significant increase in number of CD3+ cells, compared with PBS or saline solutions. Cats with EGC had a significant increase in number of CD3+ cells, compared with number of CD4+ and CD8+ cells, and Feld I caused a significant increase in number of CD3+ and CD4+ cells, compared with PBS or saline solutions. Cats with EGC had an increased CD4+ response, a significantly decreased CD8+ response, and a significantly increased CD4-to-CD8 ratio compared with healthy cats.
Conclusions and Clinical Relevance—The increased CD4+ response, significantly decreased CD8+ response, and significantly increased CD4-to-CD8 ratio are comparable to results in atopic people and allergic cats. Therefore, Feld I could be an autoallergen responsible for chronic inflammatory reactions in cats with EGC. (Am J Vet Res 2002;63:338–341)
