The gut nematode worm Heligmosomoides polygyrus compromises cellular immunity to West Nile virus in mice.
IMAGE: JANICE MURRAY AND MAIZELS LABORATORY/UNIVERSITY OF EDINBURGH
The immune system regularly encounters an array of bacteria, viruses, and multicellular organisms such as fungi and helminths. It remains unclear how the disparate responses mounted by the immune system are coordinated and the extent to which they affect one another. Desai et al. report that mice infected with the intestinal helminth Heligmosomoides polygyrus bakeri were more prone to die during West Nile virus (WNV) coinfection. Coinfected animals had alterations in their gut mucosa that allowed translocation of commensal gut bacteria and induced failure of the anti-WNV CD8 T cell response. Helminth-derived succinate triggered tuft cells in the gut to produce type 2 cytokines. The cytokines were detected by intestinal epithelium and triggered gut barrier defects. Future studies are needed to tease out whether coinfections with other flavivirus–helminth combinations cause similarly detrimental immune synergies.
Cell 184, P1214 (2021).