We are only beginning to understand how changes in skin microbiome composition are causes for, or consequences of, inflammatory skin diseases.

The lamellar membranes in the stratum corneum represent a barrier for loss of internal, or intrusion of external, molecules. At the same time, it is a source of lipid-derived nutrients and antimicrobials with crucial roles in microbiome–host interaction. The full range of lipid-hydrolytic enzymes and of fatty acid resistance mechanisms awaits further analysis.