T-helper 1, T-helper 2 and immunosuppressive cytokines in canine atopic dermatitis

Atopic dermatitis is a common inflammatory skin disease of humans and dogs. Human atopic dermatitis is associated with T-helper (Th) 2 type responses, although Th1 cytokines are present in chronic lesions. This study used semi-quantitative reverse transcriptase polymerase chain reactions to determine the expression of gene transcripts for immunosuppressive cytokines (transforming growth factor beta [TGFβ] and interleukin [IL]-10), Th2 type cytokines (IL-4 and IL-6) and Th1 type cytokines (interferon gamma [IFNγ], tumour necrosis factor alpha [TNFα], IL-2 and IL-12) in lesional atopic, non-lesional atopic and healthy canine skin. Canine atopic dermatitis was associated with over-expression of IL-4 mRNA and reduced transcription of TGFβ compared to healthy skin (ANOVA, p