IL-33 enhances LPS-mediated cytokine production by macrophages.

<p>TGC-induced peritoneal macrophages derived from B6J-WT mice (A–D) and B6N-WT and -IL-33^−/− mice (E) were cultured in the presence and absence of 100 ng/ml LPS, with and without 100 ng/ml IL-33, for 9, 24 and/or 48 h. (A, E) The levels of IL-6 in the culture supernatants by ELISA. (B) The percentage of PI-positive cells by flow cytometry. (C) LDH levels in the culture supernatants. (D) The number of IL-33-secreting cells by ELISPOT. Data show the mean +/± SEM (n = 3 [A] or 4 [B–E]). *p<0.05 vs. the indicated group (A) or Medium (B–E), and ^†p<0.05 vs. 24 h (C, D) or WT (E). P+I = PMA+ionomycin.</p

IL-33 induces TRAF6-dependent cytokine production by mast cells.

<p>BMCMCs obtained from B6J-WT mice (A) and B6J-WT and -TLR4^−/− mice (B; left panels) and FLCMCs obtained from B6J-WT and -TRAF6^−/− mice (B; right panels) were cultured in the presence of various concentration of rmIL-33 (A) or in the presence and absence of 100 ng/ml rmIL-33 for 6 h (for TNF measurement) and 24 h (for IL-6 and IL-13 measurement). The levels of IL-6, IL-13 and/or TNF in the culture supernatants were determined by ELISA. Data show the mean + SD (n = 3). *p<0.05 vs. WT.</p

Inhibitory effects of anti-IL-33 mAbs on LPS-mediated macrophage activation by paracrine IL-33 stimulation.

<p>(A, B) TGC-induced peritoneal macrophages derived from B6J-WT mice were cultured in the presence of 100 ng/ml LPS, with and without 40 µg/ml of several anti-ST2 mAbs (A), several anti-IL-33 mAbs (B) or control IgG (A, B) for 24 and 48 h. (C) B6J-WT BMCMCs were cultured in the presence of 1 µg/ml anti-DNP IgE (SPE-7), with and without 40 µg/ml of several anti-IL-33 mAbs or control IgG for 24 and 48 h. The levels of IL-6 or IL-13 in the culture supernatants were measured by ELISA. Data show the mean + SEM ([A] n = 7, [B] n = 8 [C] n = 4). *p<0.05 vs. Rat IgG (A) or Mouse IgG (B).</p

Effects of anti-ST2 mAbs on cytokine production by IL-33-stimulated BMCMCs.

<p>B6J-WT BMCMCs were stimulated with 0–1,000 ng/ml (A) or 100 ng/ml (B) rmIL-33 in the presence of 40 µg/ml of several anti-ST2 mAbs or isotype control rat IgG for 24 h. The levels of IL-6 and IL-13 in the culture supernatants were determined by ELISA. Data show the mean + SEM (n = 3). *p<0.05 vs. rat IgG+IL-33. The expression of ST2 on the cell surface of BALB-WT and ST2^−/− BMCMCs was determined using several distinct anti-ST2 mAb clones. Representative data by flow cytometry are shown (C). Shaded area indicates isotype-matched control IgG staining, and bold line indicates anti-ST2 mAb staining.</p