Abstract
Healthy human skin provides an effective mechanical as well as immunologic barrier
against pathogenic microorganisms with keratinocytes as the main cell type in the
epidermis actively participating and orchestrating the innate immune response of the
skin. As constituent of the outermost layer encountering potential pathogens they
have to sense signals from the environment and must be able to initiate a differential
immune response to harmless commensals and harmful pathogens. Staphylococci are among
the most abundant colonizers of the skin: Whereas Staphylococcus epidermidis is part of the skin microbiota and ubiquitously colonizes human skin, Staphylococcus aureus is only rarely found on healthy human skin, but frequently colonizes the skin of
atopic dermatitis (AD) patients. This review highlights recent advances in understanding
how keratinocytes as sessile innate immune cells orchestrate an effective defense
against S. aureus in healthy skin and the mechanisms leading to an impaired keratinocyte function in
AD patients.
Abbreviations:
AMP (antimicrobial peptides), AD (atopic dermatitis), ECM (extracellular matrix), FPR2 (formyl-peptide receptor 2), HMGB1 (High-Mobility-Group-Box 1), LPP (lipopeptides), MAMP (microbe-associated molecular pattern), MyD88 (myeloid differentiation factor 88), NRF2 (nuclear factor erythroid 2–related factor 2), ROS (reactive oxygen species), RTK (receptor-tyrosine kinase), TLR (toll-like receptors), PSM (phenol-soluble modulins)Keywords
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Biography
Katharina Bitschar is a PhD student at the University Hospital Tübingen in the Department of Dermatology supervised by Prof. Dr. Birgit Schittek. Her research focuses on the influence of commensal staphylococci on a Staphylococcus aureus skin infection. Thereby she is especially interested in how keratinocytes, as initial sensors of microbes, differentially trigger an adequate immune response that either leads to commensal tolerance or pathogen defense.
Article info
Publication history
Published online: June 09, 2017
Accepted:
June 7,
2017
Received in revised form:
June 2,
2017
Received:
May 30,
2017
Identification
Copyright
© 2017 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.
