Figure 2.

Sterne infection reduces the gut-associated population of type 2 innate lymphoid cells (ILC2) and their secretion of interleukin 5 (IL-5). A/J mice were orally gavaged with 10⁹ spores of the Sterne strain of Bacillus anthracis, and the ILC2 population was analyzed at indicated time points. A, Frequency of ILC2 in the colon. B, Transcriptional expression of Tslp in colonic tissues. C, Activity of mitogen-activated protein kinases in colonic ILC2 was analyzed by flow cytometry. Gray tinted line, isotype control; black line, phosphate-buffered saline (PBS) group; green line, 1 hour; magenta line, 3 hours; blue line, 6 hours Sterne-infected colonic cells isolated from A/J mice. D, Frequency of IL-5⁺ ILC2 in the colon. Left panel shows representative plots and compiled data from three independent experiments. E, Frequency of interleukin 13 (IL-13)⁺ ILC2 in the colon. Left panel shows representative plots and compiled data from 3 independent experiments. Data represent observations from 4 independent experiments and are shown as mean ± standard error of the mean. *P < .05 and **P < .01, compared with the PBS group.