Atopic dermatitis cytokine expression

In chronic lichenified atopic dermatitis skin lesions, fewer IL-4 and IL-13 mRNA-expressing cells are present, but greater numbers of IL-5, GM-CSF, IL-12, and IFN-y mRNA-expressing cells are detected. The rise in IL-5 expression during the transition from acute to chronic atopic dermatitis likely plays a role in the prolongation of eosinophil survival and function. Some of the other cytokines mentioned above support the function of macrophages and promote the Th-1-type... 

Keratinocytes secrete a unique profile of chemo-kines and cytokines after exposure to proinflam-matory cytokines. Keratinocyte-derived thymic stromal lymphopoietin (TSLP) may be of particular importance in atopic dermatitis This protein is undetectable in normal skin or non-lesional skin in patients with atopic dermatitis, but is highly expressed in acute and chronic atopic dermatitis lesions [18]. TSLP instructs human dendritic cells to create a Th-2-permissive microenvironment by inducing the expression of OX40L which triggers the differentiation of inflammatory Th-2 cells [48]. 

Howell MD, Kim BE, Gao P, Grant AV, Boguniewicz M, Debenedetto A, Schneider L, Beck LA, Barnes KC, Leung DY Cytokine modulation of atopic dermatitis filaggrin skin expression. J Allergy Clin Immunol 2007 120 150-155. 

Hamid Q, Boguniewicz M, Leung DYM Differential cytokine gene expression in acute vs chronic atopic dermatitis. J Clin Invest 1994 94 870-876. 

The traditional mainstays of topical treatment for AD have been the topical corticosteroids. It is interesting to note, however, that steroids are not believed to have any effects on histamine release from human mast cells [116, 117]. A direct comparative study of the mechanism of steroids versus tacrolimus has not been performed. However, in preliminary work done by Fujisawa Laboratories in the United States utilizing sequential punch biopsies from patients with atopic dermatitis treated with either steroids or tacrolimus topically, some differences were noted in the patterns of cytokine expression between the two treatments (M. Kobayashi, personal communication, 2000). Additional studies will need to be performed before clear conclusions can be drawn. 

Taha RA, Leung DYM, Ghaffar O, Boguniewicz M, Hamid Q. In vivo expression of cytokine receptor mRNA in atopic dermatitis. J Allergy CUn Immunol 1998 102(2) 245-250. 

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