Universal Dynamics of Human Microbial Ecosystems

Our body is colonized by trillions of microbes, known as the human microbiome, living with us in a complex ecological system. Those micro-organisms play a crucial role in determining our health and well-being, and there are ongoing efforts to develop tools and strategies to control these ecosystems. In this talk I address a simple but fundamental question: are the microbial ecosystems in different people governed by the same host-independent ecological principles, represented by a characteristic (i.e. €œuniversal) mathematical model? Answering this question determines the feasibility of general therapies and control strategies for the human microbiome. I will introduce our novel methodology that distinguishes between two scenarios: host-independent and host-specific underlying dynamics. This methodology has been applied to study different body sites across healthy subjects. We also analyzed the gut microbial dynamics of subjects with recurrent Clostridium difficile infection (rCDI) and the same set of subjects after fecal microbiota transplantation (FMT). The results can fundamentally improve our understanding of forces and processes shaping human microbial ecosystems, paving the way to design general microbiome-based therapies.