Deficiency in ST2 leads to pronounced microfilaremia and increased adult worm length.

<p>A, microfilariae count per 50 μl of peripheral blood of ST2-ko mice and wild type (WT) controls throughout <i>L. sigmodontis</i> infection. B, microfilarial burden in the thoracic cavity 60 days post <i>L. sigmodontis</i> infection. C, percentage of ST2-ko mice and WT controls that develop patent infections. D, embryogram of female worms 60dpi (6 mice per group and two female worms per mouse). E, adult worm burden in ST2-ko mice and WT controls 35, 60 and 100 dpi, (F and G) length of male and female <i>L. sigmodontis</i> worms in WT and ST2-ko mice during infection. A and C show pooled data from three independent experiments with a minimum of 8 mice per group. B shows pooled data from two independent experiments and E-G show representative data of two independent experiments with a minimum of 6 mice per group. Differences were tested for statistical significance by Mann-Whitney-U-test, *p<0.05.</p

Reduced Th2 cytokine production after in vitro restimulation of thoracic cavity cells of acute, but not chronically <i>L. sigmodontis</i> infected ST2-ko mice.

<p>Isolated cells from the thoracic cavity of individual <i>L. sigmodontis</i> infected wild type (WT) or ST2-ko mice were cultured in vitro with either <i>L. sigmodontis</i> antigen (LsAg, left panel) or ConA (right panel). IL-4 (A,B), IL-5 (C,D), IL-10 (E,F), IFNγ (G,H), IL-33 (I,J) and IL-25 (K,L) within the culture supernatants were measured on days 35, 60 or 100 post infection. Data is representative for two independent experiments with at least 5 mice per group. Differences were tested for statistical significance by Mann-Whitney-U-test, *p<0.05, **p<0.01.</p

Absence of the ST2 receptor does not change thoracic cavity IL-4, IL-5, IL-13, IL-25, IL-33 and IFNγ levels during <i>L. sigmodontis</i> infection.

<p>Local concentrations of IL-4 (A), IL-5 (B), IL-13 (C), IL-25 (D), IL-33 (E) and IFNγ (F) in the thoracic cavity lavage prior to infection (day 0) and 35, 60, and 100 days post <i>L. sigmodontis</i> infection of wild type (WT) and ST2-ko mice. Data is representative for two independent experiments with at least 5 mice per group. Differences were tested for statistical significance by Mann-Whitney-U-test.</p

ST2-ko mice have reduced thoracic cavity cell numbers throughout <i>L. sigmodontis</i> infection.

<p>Cell populations within the thoracic cavity were assessed by flow cytometry in wild type (WT) and ST2-ko mice prior to infection (day 0, only Fig. 6A) and after 35, 60 and 100 days post <i>L. sigmodontis</i> infection (Fig. 6B–F). Total number of cells within the thoracic cavity lavage (A), macrophages (B), CD4⁺ T-cells (C), B-cells (D), eosinophils (E) and neutrophils (F) are shown. Data shown is representative for two independent experiments with at least 5 mice per group. Differences were tested for statistical significance by Mann-Whitney-U-test, *p<0.05, **p<0.01.</p

ST2-ko mice have a delayed splenic clearance of transferred microfilariae.

<p>Kinetics of blood microfilariae numbers in ST2-ko mice and wild type (WT) controls after i.v. inoculation of 50,000 microfilariae (A). Blood microfilariae counts in splenectomized and sham-treated ST2-ko mice and WT controls one hour after inoculation with 50,000 microfilariae per mouse (B). Differences were tested for statistical significance by Mann-Whitney-U-test, *p<0.05. Representative data shown in (A) is from two independent experiments with at least 6 mice per group.</p