Exposure protocol of CS and HDM or PBS (adapted from [4]).

<p>The shaded region represents CS or air exposure.</p

Effect of CD44 on hyaluronic acid and osteopontin levels upon combined HSM/CS exposure.

<p>HA (A) and OPN (B) levels in BALF of WT and CD44 KO mice that were exposed for 3 weeks to PBS/air, PBS/CS, HDM/air or HDM/CS. *p<0.05, **p<0.01, ***p<0.005; n = 8–10 mice/group.</p

Effect of CD44 on lymph node cytokine production upon combined HDM/CS exposure and HDM restimulation.

<p><b>A-E:</b> Cytokine levels in supernatant of mediastinal lymph node cell cultures from WT and CD44 KO mice that were exposed for 3 weeks to PBS/air, PBS/CS, HDM/air or HDM/CS, upon restimulation with HDM. <b>A-C</b>: Th2 cytokines (IL-4, IL-5 and IL-13). <b>D:</b> Th1 cytokine (IFN-γ). <b>E:</b> Th17 cytokine (IL-17). *p<0.05, **p<0.01, ***p<0.005; n = 8–10 mice/group.</p

Effect of CD44 on airway wall eosinophilia upon combined HDM/CS exposure.

<p>Quantification of eosinophils in airway wall in WT and CD44 KO mice (<b>A</b>). Congo Red staining was used to identify eosinophils in bronchial wall (<b>B</b>). *p<0.05, **p<0.01, ***p<0.005; n = 8–10 mice/group.</p

Effect of CD44 on proinflammatory mediator production upon combined HDM/CS exposure.

<p>Proinflammatory mediator levels in lungs of WT and CD44 KO mice. IL-1β (A) and IL-33 (B) protein levels and CXCL1 (C) and CCL11 (D) mRNA expressions. *p<0.05, **p<0.01, ***p<0.005; n = 10 mice/group.</p

Effect of CD44 on goblet cell formation upon combined HDM/CS exposure.

<p>Quantification of mucus producing cells in WT and CD44 KO mice (<b>A</b>). Periodic acid-Schiff (PAS) stain was used to identify goblet cells in the airway mucosa (<b>B-F</b>).ⱡ: Figure representative of PBS/Air and PBS/CS of WT and CD44 KO mice. *p<0.05, **p<0.01, ***p<0.005; n = 8–10 mice/group.</p

Histology of the joints in WT and TNF^ΔARE mice.

<p>H&E staining of the ankle joints of <b>(A)</b> air-exposed WT mice, <b>(B)</b> CS-exposed WT mice, <b>(C)</b> air-exposed TNF^ΔARE mice and <b>(D)</b> CS-exposed TNF^ΔARE mice. <b>(E)</b> Histological score of inflammation in the joints of WT and TNF^ΔARE mice. Histological inflammation is increased in TNF^ΔARE mice compared to WT mice (p < 0,005). Data are expressed as mean ± SEM. * p<0.05, ** p<0.01, *** p<0.001.</p

Histologic score to quantify the degree of ileal inflammation.

<p>PMN: polymorphonuclear cells. ML: mononuclear leukocytes. Hpf: high power field. Scoring scheme adapted from Kontoyiannis et al, 2002.</p><p>Histologic score to quantify the degree of ileal inflammation.</p

Inflammatory gene expression in lung tissue and BAL fluid of WT and TNF^ΔARE mice.

<p>mRNA expression of <b>(A)</b> Tnf-α, <b>(C)</b> Tnfr1, <b>(D)</b> Tnfr2, <b>(E)</b> Ccl2, <b>(F)</b> Cxcl1 and <b>(G)</b> Cxcl2 in lung tissue of WT and TNF^ΔARE mice exposed to air or CS during 2 weeks. <b>(B)</b> Protein levels of TNF-α in BAL fluid of WT and TNF^ΔARE mice exposed to air or CS during 2 weeks. mRNA expression of <b>(H)</b> Tnf-α, <b>(J)</b> Tnfr1, <b>(K)</b> Tnfr2, <b>(L)</b> Ccl2, <b>(M)</b> Cxcl1 and <b>(N)</b> Cxcl2 in lung tissue of WT and TNF^ΔARE mice exposed to air or CS during 4 weeks. <b>(I)</b> Protein levels of TNF-α in BAL fluid of WT and TNF^ΔARE mice exposed to air or CS during 4 weeks. Expression levels are relative to the expression of 3 reference genes (hypoxanthine phosphoribosyltransferase 1 (Hprt1), glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and transferring receptor protein 1 (Tfrc)). Values are expressed as mean ± SEM. * p<0.05, ** p<0.01, *** p<0.001.</p

Mean clinical arthritis score in WT and TNF^ΔARE mice.

<p>Clinical arthritis score during the course of <b>(A)</b> 2 weeks (WT vs. TNF^ΔARE: p < 0,005) and <b>(B)</b> 4 weeks CS exposure (WT vs. TNF^ΔARE: p < 0,005).</p