Gut microbiota density influences host physiology and is shaped by host and microbial factors.

Unlabelled: To identify factors that regulate gut microbiota density and the impact of varied microbiota density on health, we assayed this fundamental ecosystem property in fecal samples across mammals, human disease, and therapeutic interventions. Physiologic features of the host (carrying capacity) and the fitness of the gut microbiota shape microbiota density. Therapeutic manipulation of microbiota density in mice altered host metabolic and immune homeostasis.

Microbiotas from Humans with Inflammatory Bowel Disease Alter the Balance of Gut Th17 and RORγt Regulatory T Cells and Exacerbate Colitis in Mice.

Microbiota are thought to influence the development and progression of inflammatory bowel disease (IBD), but determining generalizable effects of microbiota on IBD etiology requires larger-scale functional analyses. We colonized germ-free mice with intestinal microbiotas from 30 healthy and IBD donors and determined the homeostatic intestinal T cell response to each microbiota. Compared to microbiotas from healthy donors, transfer of IBD microbiotas into germ-free mice increased numbers of intestinal Th17 cells and Th2 cells and decreased numbers of RORγt Treg cells.

Participating more, participating better: Health benefits of adaptive leisure for people with disabilities.

Background: Increasing participation in recreational leisure activities (RLA) could be an effective vehicle for social inclusion and improvement - people's with disabilities health. Unfortunately, many barriers limit their participation in RLA. Interventions to improve access to RLA are often limited to therapeutic or adaptive sports in rehabilitation.