title: Review: Lymphocytes, cytokines, chemokines and the T-helper 1-T-helper 2 balance in canine atopic dermatitis.
abstract: BACKGROUND
  The development of atopic dermatitis (AD) and other cutaneous hypersensitivities involves the activation and differentiation of allergen-specific lymphocytes. Although hypersensitivity is often considered to be a 'T-helper 2-polarized' lymphocyte response, recent evidence suggests that clinical disease is associated with the development of multiple lymphocyte phenotypes.
  
  
  OBJECTIVE
  The purpose of this paper is to review recent advances in the understanding of the roles of lymphocytes, cytokines and noncytokine factors in the pathogenesis of canine AD.
  
  
  METHODS
  Citation databases, abstracts and proceedings from international meetings published between 2001 and 2013 were reviewed in this update. Where necessary, older articles were included for background information.
  
  
  RESULTS
  The development of canine AD is associated with changes in both cutaneous and circulating lymphocyte populations. These lymphocyte responses are characterized by the production of a complex variety of cytokines, including not only T-helper 2 but also T-helper 1, T-helper 17 and regulatory T-cell responses. In addition, microarray gene expression analysis has enabled the identification of a number of noncytokine factors that appear to be associated with atopic inflammation. These include the calcium-binding protein S100A8, serum amyloid A and a number of protease inhibitors, as well as genes involved in epidermal barrier formation, innate immunity receptors, cell cycle proteins and apoptosis.
  
  
  CONCLUSIONS
  The development of AD in dogs is characterized by the development of a delicate balance between a variety of T-cell phenotypes and inflammatory mediators, including cytokines, chemokines and noncytokine factors.
authors: Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, 1909 Skip Bertman Drive, Baton Rouge, LA, 70803, USA.
authors: Cherie M
authors: CM
authors: Pucheu-Haston
authors: Petra
authors: P
authors: Bizikova
authors: Rosanna
authors: R
authors: Marsella
authors: Domenico
authors: D
authors: Santoro
authors: Tim
authors: T
authors: Nuttall
authors: Melissa N C
authors: MN
authors: Eisenschenk
mesh_terms: D000818:Animals; D018925:Chemokines / Q000235:genetics / Q000378:metabolism; D016207:Cytokines / Q000235:genetics / Q000378:metabolism*; D003876:Dermatitis, Atopic / Q000276:immunology / Q000378:metabolism / Q000662:veterinary*; D004283:Dog Diseases / Q000276:immunology* / Q000378:metabolism; D004285:Dogs; D008214:Lymphocytes / Q000502:physiology*; D006377:T-Lymphocytes, Helper-Inducer / Q000145:classification / Q000502:physiology*
chemical_list: D018925:Chemokines; D016207:Cytokines