Role of Formyl Peptide Receptor 2 and Toll-Like Receptor 2 in Skin Barrier Function and Atopic Dermatitis

The skin acts as a barrier against external threats and plays an important role in tissue repair. Skin cells, including keratinocytes, sense microbe-associated molecular pattern molecules released by members of the bacterial microbiome, and the cellular responses control central processes of skin homeostasis or inflammation. How the combination and amount of different microbe-associated molecular patterns modulate skin cell functions is not yet fully understood. Here, we review the current knowledge of the responses of skin cells to microbe-associated molecular patterns, focusing on Toll-like receptor 2 and formyl peptide receptor 2, two of the most important receptors for sensing the skin microbiome.