Figure 1. ILC2s Increases in the Heart, and Cardiac Function Is Changed following IL-33 Treatment.

(A) Representative images of H&E-stained heart sections of the median mice treated with either PBS or IL-33. Areas marked by rectangles are shown as enlarged images in the right panels. Bars: 1 mm (left) and 100 μm (right).

(B) Representative M-mode pictures of animals treated with PBS or IL-33. Bars: blue, 1 mm; white, 0.1 s. LVESD, left ventricular end-systolic diameter; LVEDD, left ventricular end-diastolic diameter.

(C and D) Ejection fraction (EF) (C) and fractional shortening (FS) (D) of WT mice treated with PBS or IL-33.

(E and F) Isovolumetric relaxation time (IVRT) (E) and myocardial performance indexes (MPI) (F) of the heart from mice treated with PBS or IL-33 were assessed by Doppler echocardiography on day 9 post-PBS or IL-33 treatment.

(G) Total number of heart-infiltrating CD45⁺ leukocytes was determined by flow cytometry.

(H–J) Number of (H) ILC2s, (I) eosinophils, and (J) mast cells in the hearts. Absolute cell counts per heart were calculated using counting beads for flow cytometry (see Method Details).

(K) Image of the right ventricle of the heart from Rag2^−/− mice treated with IL-33. Green and red dots represent KLRG1⁺ ILC2s (white arrows) and SiglecF⁺ eosinophils (red arrowheads), respectively. Scale bar: 500 μm. Data are representative of three independent experiments.

Data are displayed as the means. Unpaired t test (C–J) was used for statistical analysis. *p < 0.05; **p < 0.01; ***p < 0.001.

See also Figures S1 and S2 and Video S1.