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arXiv · 1404.6668

Host-to-host variation of ecological interactions in polymicrobial infections

Sayak Mukherjee·Kristin E. Weimer·Sang-Cheol Seok·Will C. Ray·C. Jayaprakash·Veronica J. Vieland·W. Edward Swords·Jayajit Das
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Abstract

Host-to-host variability with respect to interactions between microorganisms and multicellular hosts are commonly observed in infection and in homeostasis. However, the majority of mechanistic models used in analyzing host-microorganism relationships, as well as most of the ecological theories proposed to explain co-evolution of host and microbes, are based on averages across a host population. By assuming that observed variations are random and independent, these models overlook the role of inter-host differences. Here we analyze mechanisms underlying host-to-host variations, using the well-characterized experimental infection model of polymicrobial otitis media (OM) in chinchillas, in combination with population dynamic models and a Maximum Entropy (MaxEnt) based inference scheme. We find that the nature of the interactions among bacterial species critically regulates host-to-host variations of these interactions. Surprisingly, seemingly unrelated phenomena, such as the efficiency of individual bacterial species in utilizing nutrients for growth and the microbe-specific host immune response, can become interdependent in a host population. The latter finding suggests a potential mechanism that could lead to selection of specific strains of bacterial species during the coevolution of the host immune response and the bacterial species.

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Sayak Mukherjee, Kristin E. Weimer, Sang-Cheol Seok, Will C. Ray, C. Jayaprakash, Veronica J. Vieland, W. Edward Swords, Jayajit Das. 2014-04-26. Host-to-host variation of ecological interactions in polymicrobial infections. https://doi.org/10.1088/1478-3975%2F12%2F1%2F016003

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