Cutaneous Leishmaniasis Induces a Transmissible Dysbiotic Skin Microbiota that Promotes Skin Inflammation

• Published in: Cell host & microbe Vol. 22; no. 1; pp. 13 - 24.e4
• Main Authors: Gimblet, Ciara, Meisel, Jacquelyn S., Loesche, Michael A., Cole, Stephen D., Horwinski, Joseph, Novais, Fernanda O., Misic, Ana M., Bradley, Charles W., Beiting, Daniel P., Rankin, Shelley C., Carvalho, Lucas P., Carvalho, Edgar M., Scott, Phillip, Grice, Elizabeth A.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 12-07-2017
• Subjects: Animals; cutaneous inflammation; Disease Models, Animal; dysbiosis; Dysbiosis - etiology; Dysbiosis - immunology; Humans; Hypersensitivity; Inflammation - immunology; Inflammation - microbiology; leishmania; Leishmania braziliensis - pathogenicity; Leishmania major - immunology; Leishmania major - pathogenicity; Leishmaniasis, Cutaneous - complications; Leishmaniasis, Cutaneous - microbiology; Mice; Mice, Inbred C57BL; microbiota; Microbiota - immunology; Microbiota - physiology; skin; Skin - immunology; Skin - microbiology; Skin - parasitology; Staphylococcus - immunology; Staphylococcus - pathogenicity; Streptococcus - immunology; Streptococcus - pathogenicity; microbiota; skin; cutaneous inflammation; leishmania; dysbiosis
• ISSN: 1931-3128; 1934-6069
• DOI: 10.1016/j.chom.2017.06.006

Skin microbiota can impact allergic and autoimmune responses, wound healing, and anti-microbial defense. We investigated the role of skin microbiota in cutaneous leishmaniasis and found that human patients infected with Leishmania braziliensis develop dysbiotic skin microbiota, characterized by increases in the abundance of Staphylococcus and/or Streptococcus. Mice infected with L. major exhibit similar changes depending upon disease severity. Importantly, this dysbiosis is not limited to the lesion site, but is transmissible to normal skin distant from the infection site and to skin from co-housed naive mice. This observation allowed us to test whether a pre-existing dysbiotic skin microbiota influences disease, and we found that challenging dysbiotic naive mice with L. major or testing for contact hypersensitivity results in exacerbated skin inflammatory responses. These findings demonstrate that a dysbiotic skin microbiota is not only a consequence of tissue stress, but also enhances inflammation, which has implications for many inflammatory cutaneous diseases.
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•Leishmania infection alters the skin microbiota of both humans and mice•Dysbiosis is characterized by a dominance of Staphylococcus and/or Streptococcus•Naive mice acquire dysbiosis when co-housed with leishmania-infected mice•Acquiring a dysbiotic microbiota prior to infection exacerbates skin inflammation
The role of skin commensal microbes in dermal cellular responses is largely unknown. Gimblet et al. investigate the role of the skin microbiota during cutaneous leishmaniasis. Leishmania infection creates a dysbiotic skin microbiota that is transmissible to naive skin. Additionally, dysbiosis prior to infection or injury exacerbates skin inflammation.