Manipulation of host and parasite microbiotas: Survival strategies during chronic nematode infection

Copyright © 2018 The Authors, some rights reserved. Intestinal dwelling parasites have evolved closely with the complex intestinal microbiota of their host, but the significance of the host microbiota for metazoan pathogens and the role of their own intestinal microbiota are still not fully known.Wehave found that the parasitic nematode Trichuris muris acquired a distinct intestinalmicrobiota from its host, which was required for nematode fitness. Infection of germ-free mice and mice monocolonized with Bacteroides thetaiotaomicron demonstrated that successful T. muris infections require a host microbiota. Following infection, T. muris-induced alterations in the host intestinal microbiota inhibited subsequent rounds of infection, controlling parasite numbers within the host intestine. This dual strategy could promote the long-Term survival of the parasite within the intestinal niche necessary for successful chronic nematode infection.The Bioimaging Facility microscopes used in this study were purchased withgrants from the UK Biotechnology and Biological Sciences Research Council, the WellcomeTrust, and the University of Manchester Strategic Fund. This work was supported by WellcomeTrust grant WT 100290MA awarded to R.K.G. and by UK Biotechnology and BiologicalSciences Research Council grant BB/J014478/1 and Medical Research Council grant G1100076both awarded to I.S.R. and R.K.G. R.K.G. also acknowledges the Wellcome Trust Centrefor Cell Matrix Research Centre Award 203128/Z/16/Z