Atopic Dermatitis Microbes Profiled by Sequencing in Pediatric Patients

In a paper appearing in Cell Host & Microbe, a team from the Massachusetts Institute of Technology and other centers in the US, Mexico, and Germany describe Staphylococcus aureus adaptations found in nearly two dozen children with moderate to severe atopic dermatitis. Using samples from atopic dermatitis-affected and -unaffected skin sites from 23 children, the investigators sequenced 1,499 S. aureus genomes, identifying stable lineages in individual children, coupled with relatively rapid de novo mutation S. aureus lineage sweeps involving multiple body sites in a given patient. In the process, they also saw several examples atopic dermatitis-associated S. aureus microbes carrying capD gene mutations that interfered with the production of a capsule that usually surrounds the bacterial cell wall — a pattern that was overrepresented in atopic dermatitis cases in a subsequent analysis. "Together, our results highlight the potential of de novo mutations for altering bacterial competitiveness in microbiomes, highlight the power of mutation tracking for identifying new potential therapeutic directions, and suggest that whole-genome resolution may be required for predicting the impact of microbial stains on complex diseases," they write.