Fig. 1. Symbiotic protozoa or helminths increase intestinal tuft cell abundance.

(A) DCLK1⁺ tuft cell frequency in the small intestine (SI) of WT BIH and WT JAX mice. (B) Hemtoxylin and eosin-stained SI sections from WT BIH and WT JAX mice (scale bar, 50 μm) (left). A higher magnification of the WT BIH section is shown on the right (scale bar, 20 μm). (C) SEM micrograph of protozoa isolated from WT BIH mice (scale bar, 4 μm). (D) Tm abundance in stool DNA (Tm 28S rRNA relative to Eubacteria 16S rRNA), determined by qPCR (ND, not detectable). (E) Representative SI images from uninfected and Tm-colonized mice and (F) tuft cell frequency. (G) Representative SI images from uninfected and helminth-colonized mice and (H) tuft cell frequency. DCLK1 is shown in green, E-cadherin in red, and DAPI (4′,6-diamidino-2-phenylindole) in blue [scale bars in (E) and (G), 100 μm]. Each symbol represents an individual mouse, and all data are representative of two [(D), (F), and (H)] or three (A) independent experiments. Tm infection was 17 days in (E) and (F). In (G) and (H), Hp infection was 21 days, Ts infection was 15 days, and Nb infection was 8 days. Data are plotted as means with SD. Four stars, P < 0.0001; three stars, P = 0.0001; one-way analysis of variance (ANOVA) or Mann-Whitney test.