Researchers from National Institutes of Health in US found that millions of naturally occurring commensal bacteria in the skin collectively known as the skin microbiota contribute to protective immunity by interacting with the immune cells in the skin.
The study was published in journal Science.
The investigators colonised germ-free mice (mice bred with no naturally occurring microbes in the gut or skin) with the human skin commensal Staphylococcus epidermidis.
The team observed that colonising the mice with this one species of good bacteria enabled an immune cell in the mouse skin to produce a cell-signaling molecule needed to protect against harmful microbes.
The researchers subsequently infected both colonised and non-colonised germ-free mice with a parasite. Mice that were not colonised with the bacteria did not mount an effective immune response to the parasite, mice that were colonised did.
The study demonstrated that skin health relies on the interaction of commensals and immune cells, the researchers said in a statement.
The study was led by investigators in the laboratories of Yasmine Belkaid at the National Institute of Allergy and Infectious Diseases, in collaboration with Julie Segre at the National Human Genome Research Institute, and Giorgio Trinchieri, and Heidi Kong at the National Cancer Institute.