Helminth-induced reprogramming of the stem cell compartment inhibits type 2 immunity

Karo-Atar et al. demonstrate direct regulation of the intestinal stem cell compartment by an enteric helminth, resulting in expansion of fetal-like stem cells and inhibition of secretory cells. They establish how a helminth parasite co-opts a tissue development program to counter type 2 immune-mediated expulsion. Enteric helminths form intimate physical connections with the intestinal epithelium, yet their ability to directly alter epithelial stem cell fate has not been resolved. Here we demonstrate that infection of mice with the parasite Heligmosomoides polygyrus bakeri (Hpb) reprograms the intestinal epithelium into a fetal-like state marked by the emergence of Clusterin-expressing revival stem cells (revSCs). Organoid-based studies using parasite-derived excretory-secretory products reveal that Hpb-mediated revSC generation occurs independently of host-derived immune signals and inhibits type 2 cytokine-driven differentiation of secretory epithelial lineages that promote their expulsion. Reciprocally, type 2 cytokine signals limit revSC differentiation and, consequently, Hpb fitness, indicating that helminths compete with their host for control of the intestinal stem cell compartment to promote continuation of their life cycle.