A perturbed skin microbiome resulting from cutaneous leishmaniasis can be ‘contagious’, promoting skin inflammation in other subjects, researchers from the University of Pennsylvania report online in Cell Host & Microbe (June 29, 2017).
In their research, the investigators found that human patients infected with Leishmania braziliensis develop imbalances in the microbiota on their skin - dysbiosis – characterized by increases in the abundance of Staphylococcus or Streptococcus bacteria.
When they examined the same type of Leishmania infection in mice, they not only found similar dysbiosis related to the disease severity, but that dysbiosis was not limited to the leishmaniasis lesion site. It could be transmitted to distant, unaffected skin, or even to other mice in the same enclosure who did not have leishmaniasis.
“To my knowledge, this is the first case where anyone has shown that a pre-existing skin microbiome can influence the outcome of an infection or a disease,” Dr. Elizabeth Grice, co-senior author and assistant professor in the departments of Dermatology and Microbiology in Penn’s Perelman School of Medicine, said in a press release. “This opens the door to many other avenues of research.”
‘Contagion’ of an altered microbiome state was of particular interest, note the authors.
“The transmission of dysbiosis in the skin from one animal to another is a key finding,” said Phillip Scott, PhD, professor of immunology in the Department of Pathobiology in Penn’s School of Veterinary Medicine and co-senior author on the study, in the release. “And the fact that we saw similar patterns of dysbiosis in humans suggests there could be some very practical implications of our work when it comes to treating people with leishmaniasis.”
The investigators hope to see whether the sharing of perturbed microbiota happens not just in mouse cages but also in households.
“I think an important next step will be to see if this sharing of microbiota occurs in people, and whether that could be a factor in affecting the severity of infections in humans,” Dr. Grice said.