A special guest post from Ashley Bateman.
Roller derby players share their skin microbes during play
Single-celled organisms are intimately associated with multicellular organisms across the tree of life, and human beings are no exception. Making up 90% of our cellular composition, these invisible passengers (our microbiome) contribute to our health and well-being in crucial ways, including aiding our digestion, the education of our immune system, and resistance to pathogens. Despite this importance, we still lack a fundamental understanding of where our host-associated microbes actually come from. We know that infants are born practically sterile; early-life events such as birth mode can contribute to the types of microbial species found on an individual, but these events cannot adequately explain the majority of spatiotemporal variation observed over a host’s lifetime. To be able to accurately describe the processes that drive host-associated microbial community dynamics, we must have an informed understanding of the role of dispersal in structuring host-associated microbial communities.
Where do they come from? How do they get there? Do these changes (if any) last?
The Green Lab at the University of Oregon-Eugene attempted to answer some of these questions in our latest publication “Significant changes in the skin microbiome mediated by the sport of Roller Derby”, released today by PeerJ. We decided to use Roller Derby as a model system to investigate the role of contact in dispersing skin microbial communities between hosts. We have known for a long time that pathogens can be transmitted via direct contact; could not our commensal microbial communities be shared in this way?
We swabbed the upper arms (a frequent contact point between players during a bout) of players belonging to 3 geographically distinct derby teams and characterized the skin microbiome of each player using 16s rRNA gene Illumina sequencing. We found that each team’s upper arm microbiome was significantly different from one another before play, and that this difference decreased after bouts were played. Not only did teams’ skin microbiomes become less different from one another after play, but the differences were driven in part “by the presence of unique indicator taxa that are commonly associated with human skin, gut, mouth, and respiratory tract.” There were also environmental bacteria associated with soil and plants found in the skin samples.
Although we weren’t able to show a direct link between contact and transfer of specific microbial taxa, the best explanation of the data seems to be that contact between these players during a one-hour bout effectively resulted in homogenization of their upper arm skin microbiomes.
So much yet to explore! As a 2nd year graduate student in the Green Lab I hope to address some of the questions that the Roller Derby paper has brought to our attention. My dissertation research is gearing up to understand the role of dispersal on our skin microbiome. Are some skin sites more amenable to changes than others? Can we pick up host-associated microbes not just from other individuals, but from objects that other individuals have touched? Can we pick up non-host-associated microbes? If we can pick them up, how long do they stick around? How do they participate in the functions attributed to the skin microbiome?
Hope to keep up the fantastic momentum that has been launched by this latest publication – if you have any thoughts or comments, feel free to contact me at email@example.com, or via Twitter: @microbesrock
And you can check out a stop-motion video I made on the skin microbiome here: