Acne vulgaris, which occurs in 44-95% of teenagers of varying ethnicities, represents a natural, transient inflammatory interaction of adolescent facial skin with new microbes and enhanced production of an oily substance called sebum, according to a new paper published in the journal Trends in Immunology. Model of dynamic interactions between the skin immune system (SIS) and its microbial/chemical milieu in human facial skin: (A) infancy — before...