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PubMed · 10515840

Tumor necrosis factor-alpha and interleukin-1alpha decrease the adherence of Streptococcus pyogenes to cultured keratinocytes.

G L Darmstadt·P Fleckman·C E Rubens
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Abstract

We hypothesized that the primary epidermal cytokines, tumor necrosis factor (TNF)-alpha and interleukin (IL)-1alpha, which are produced after skin injury, modulate bacterial adherence and the initiation of group A streptococcal skin infections. Streptococcus pyogenes binds preferentially to highly differentiated keratinocytes in vitro, simulating the superficial human skin infection, impetigo, and providing a model system for testing this hypothesis. Exposure of keratinocytes to 10 ng/mL TNF-alpha for 20 h decreased adherence to undifferentiated and differentiated keratinocytes by 33% and 38%, respectively. Treatment with 1 ng/mL IL-1alpha decreased adherence to undifferentiated and differentiated keratinocytes by 23% and 18%, respectively. Exposure to both cytokines simultaneously produced an additive 50% reduction in adherence. These data suggest that TNF-alpha and IL-1alpha may play a role in cutaneous host defense by impeding streptococcal adherence and decreasing its ability to form a nidus of infection in the skin.

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Bacterial AdhesionCells, CulturedHumansIntercellular Adhesion Molecule-1Interleukin-1KeratinocytesStreptococcus pyogenesTumor Necrosis Factor-alphaJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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G L Darmstadt, P Fleckman, C E Rubens. 1999. Tumor necrosis factor-alpha and interleukin-1alpha decrease the adherence of Streptococcus pyogenes to cultured keratinocytes.. https://doi.org/10.1086/315066

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