Figure 1. IL-33 is upregulated in hepatic fibrosis.

(A) Serum IL-33 (n=11/group; ***p<0,001) in healthy controls or cirrhosis patients was determined by ELISA. (B) Serum IL-33 protein concentrations in control mice or mice with TAA or CCL₄ induced liver fibrosis. (n=5/group; **p<0.01; ***p<0.001) were determined. (C) Representative images of liver sections from CCL₄, TAA, S. mansoni infected and control treated mice stained for IL-33 by immunohistochemistry. Scale bars 50μm. (D) 2,5μg of mcIL-33 expression or control vector (mock) was HD injected into mice. Mice were analyzed 4 weeks later. Liver sections were stained for IL-33 protein, with HE or, for visualization of collagen, with Sirius red. (E) IL-33 serum concentrations in mcIL-33 treated mice (***p<0,001) were determined by ELISA. Scale bars 100μm (IL-33 staining) or 200μm (HE and Sirius Red). (F) Total hepatic collagen of indicated mice was quantified by hydroxyproline assay (n=9-10/group: ***p<0.001)). (G) mRNAs of selected fibrosis associated genes in liver total RNA were quantified by qPCR. (n=9-10/group; ***p<0.001; *p<0,05). Data are representative of at least two different experiments with similar results. (H) CD1 mice infected with ~ 30 S. mansoni cercaria were HD injected with mcIL-33 at week 3 after infection. 3 weeks later mice were sacrificed and organ weights were determined. Hepatic collagen content was determined by hydroxyproline quantification. (n=5/group; **p<0.01; *p<0.05). Data are representative of 2 different experiments with similar results.