SUMMARY
The intestinal parasite, Cryptosporidium, is a major contributor to global child mortality and causes opportunistic infection in immune deficient individuals. Innate resistance to Cryptosporidium, which specifically invades enterocytes, is dependent on the production of IFN-γ, yet whether enterocytes contribute to parasite control is poorly understood. In this study, utilizing the natural mouse pathogen, Cryptosporidium tyzzeri, we show that epithelial-derived IL-18 synergized with IL-12 to stimulate innate lymphoid cell (ILC) production of IFN-γ. This innate IFN-γ was required for early parasite control. Loss of STAT1 in enterocytes, but not dendritic cells or macrophages, antagonized early parasite control. Transcriptional profiling of enterocytes from infected mice identified an IFN-γ signature and enrichment of anti-microbial effectors like IDO, GBP and IRG. Deletion experiments identified a role for Irgm1/m3 in parasite control. Thus, enterocytes promote ILC production of IFN-γ that acts on enterocytes to restrict the growth of C. tyzzeri.
Competing Interest Statement
The authors have declared no competing interest.
Footnotes
This work was supported in part by funding from the Bill and Melinda Gates Foundation (OPP1183177) to BS and through grants from the U.S. National Institutes of Health to BS & CAH (R01AI148249), R21 AI139895 to CAH, and fellowships and career awards to JG (T32AI055400), AS (K99AI137442), and AG (T32A1055400) and a Swiss National Science Foundation fellowship (191774) to SB.