Enteric tuft cells coordinate timely expulsion of the tapeworm Hymenolepis diminuta from the murine host by coordinating local but not systemic immunity

PLoS Pathog. 2024 Jul 31;20(7):e1012381. doi: 10.1371/journal.ppat.1012381. eCollection 2024 Jul.

Abstract

Recognizing that enteric tuft cells can signal the presence of nematode parasites, we investigated whether tuft cells are required for the expulsion of the cestode, Hymenolepis diminuta, from the non-permissive mouse host, and in concomitant anti-helminthic responses. BALB/c and C57BL/6 mice infected with H. diminuta expelled the worms by 11 days post-infection (dpi) and displayed DCLK1+ (doublecortin-like kinase 1) tuft cell hyperplasia in the small intestine (not the colon) at 11 dpi. This tuft cell hyperplasia was dependent on IL-4Rα signalling and adaptive immunity, but not the microbiota. Expulsion of H. diminuta was slowed until at least 14 dpi, but not negated, in tuft cell-deficient Pou2f3-/- mice and was accompanied by delayed goblet cell hyperplasia and slowed small bowel transit. Worm antigen and mitogen evoked production of IL-4 and IL-10 by splenocytes from wild-type and Pou2f3-/- mice was not appreciably different, suggesting similar systemic immune reactivity to infection with H. diminuta. Wild-type and Pou2f3-/- mice infected with H. diminuta displayed partial protection against subsequent infection with the nematode Heligmosomoides bakeri. We speculate that, with respect to H. diminuta, enteric tuft cells are important for local immune events driving the rapidity of H. diminuta expulsion but are not critical in initiating or sustaining systemic Th2 responses that provide concomitant immunity against secondary infection with H. bakeri.

MeSH terms

  • Animals
  • Female
  • Hymenolepiasis* / immunology
  • Hymenolepiasis* / parasitology
  • Hymenolepis diminuta* / immunology
  • Hyperplasia / immunology
  • Hyperplasia / parasitology
  • Intestine, Small / immunology
  • Intestine, Small / parasitology
  • Intestine, Small / pathology
  • Mice
  • Mice, Inbred BALB C*
  • Mice, Inbred C57BL*
  • Mice, Knockout
  • Tuft Cells

Grants and funding

S. Rajeev is a recipient of the Univ. Calgary Eye’s High Doctoral and the Maria Fotaki International doctoral scholarships for international students, Alberta Graduate Excellence Scholarship and the H. Koopman’s Memorial Award for stipend support. S. Li is a recipient of a Natural Science and Engineering Research Council of Canada (NSERC) graduate studentship, Beverly Phillip’s Graduate Scholarship through the Snyder Institute for Chronic Diseases, a H. Koopman’s Memorial Award and a Univ. Calgary Eyes High Doctoral Recruitment Scholarship for stipend support. This research was supported by an NSERC discovery grant (RGPIN-2017-03826) to D. McKay. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.