Superantigen-induced cytokine expression in organ-cultured human skin.

Bacterial superantigen such as staphylococcal enterotoxin B (SEB) induced strong ICAM-1 expression in organ-cultured human keratinocytes. Other superantigens (SEA, SEC1, SEC2) but not mite antigen (Dermatophagoides) also induced ICAM-1 expression both at protein and mRNA level. In contrast to ICAM-1, vascular endothelial cell expression of VCAM-1 was only demonstrated at mRNA level following ICAM-1 expression in keratinocytes. Patterns of cytokine expression in keratinocytes were variable. TNF alpha was strongly expressed in keratinocytes both at protein and mRNA level, while IL1 beta and IL1 alpha were only demonstrated at mRNA level. These results clearly demonstrated that bacterial superantigen could induce cell adhesion molecule expression in keratinocytes through the induction of various cytokines and play an important role in the induction of refractory eczematous lesions in atopic dermatitis.