Airway responsiveness, lung cell infiltration and OVA-specific IgE serum levels.

<p>Mice (n = 8) were sensitized with OVA/Alum and received 3 OVA or PBS inhalation challenges. TLR-2 agonist (20 µg per mouse in PBS) or PBS was administered intranasally 1 hour before each challenge. Asthma manifestations were measured one day after the last challenge. A: Airway responsiveness to increasing doses of methacholine was measured by whole-body plethysmography and is expressed as enhanced pause (PenH) (gray symbols: PBS-challenged groups, white symbols: OVA-challenged groups, squares: Pam3Cys-treated groups, triangles: PBS-treated groups). B, C: total (B) and differential (C) cell counts in the BAL of OVA-challenged mice. D: OVA-specific IgE levels in the serum of OVA-challenged mice. (E) Lung tissue cytokines measured in lung homogenates of PBS or Pam3Cys (P3C) treated mice as indicated. All values are displayed as average ± SEM (panels A–D) or individual values (dots)+mean (bar) (panel E). Significance is indicated (*) when p<0.05.</p

Airway responsiveness, lung cells infiltration and OVA-specific IgE serum levels.

<p>Mice (n = 8) were sensitized with OVA/Alum and received a first series of 3 OVA inhalation challenges, during which TLR-2 agonist (20 µg per mouse in PBS) or PBS was administered intranasally 1 hour before challenge. After 3 weeks, mice received a second series of 3 inhalation challenges (OVA or PBS). Asthma manifestations were measured one day after the last challenge. A: Airway responsiveness to increasing doses of methacholine was measured by whole-body plethysmography and is expressed as enhanced pause (PenH) (gray symbols: PBS-challenged groups, white symbols: OVA-challenged groups, squares: Pam3Cys-treated groups, triangles: PBS-treated groups). B: total cell counts in the BAL of PBS and OVA-challenged mice as indicated. C: differential cell counts in the BAL of OVA-challenged mice only. D: OVA-specific IgE levels in pre-challenge and post-challenge sera of OVA-challenged mice. (E) Lung tissue cytokines measured in lung homogenates of PBS or Pam3Cys (P3C) treated mice after OVA challenge at timepoint 1 (left-hand panel) or at timepoint 2 (right-hand panel) as indicated. All values in panels A–D are displayed as average ± SEM, panel E displays individual values (dots)+mean (bar). Significance is indicated (*) when p<0.05.</p

Time schedule of the experimental procedures.

<p>Days of sensitization, OVA/PBS challenges, Pam3Cys/PBS treatments and lung function measurements/section are indicated for both the short protocol (A) and the long-term protocol (B).</p

Airway responsiveness, BAL cell counts and composition, and OVA-specific IgE serum levels.

<p>Mice (n = 8) were sensitized with OVA/Alum and received 4 OVA or PBS inhalation challenges. TLR-2 agonist (20 µg per mouse in PBS) or PBS was administered intranasally 1 hour before the 2 first challenges. Asthma manifestations were measured one day after the last challenge. A: Airway responsiveness to increasing doses of methacholine was measured by whole-body plethysmography and is expressed as enhanced pause (PenH) (gray symbols: PBS-challenged groups, white symbols: OVA-challenged groups, squares: Pam3Cys-treated groups, triangles: PBS-treated groups). B, C: total (B) and differential (C) cell counts in the BAL of PBS and OVA-challenged mice as indicated. D: OVA-specific IgE levels in the serum of PBS and OVA-challenged mice as indicated. All values are displayed as average ± SEM.</p

Par-2-deficiency does not influence the inflammatory response after HDM exposure.

<p>Total cell counts and mononuclear, eosinophil and neutrophil fractions in BALF from Wt or Par-2 deficient mice after chronic exposure to PBS or HDM (Greer/Citeq). BALF cells were counted 24 hours after the last PBS/HDM exposure. Total cell count after PBS and (A) HDM Greer exposure or (B) HDM Citeq exposure, Mononuclear cell count (%) after PBS and (C) HDM Greer exposure or (D) HDM Citeq exposure, Eosinophil cell count (%) after PBS and (E) HDM Greer exposure or (F) HDM Citeq exposure, Neutrophil cell count (%) after PBS and (G) HDM Greer exposure or (H) HDM Citeq exposure. Median levels are shown (n = 7–8 mice per group). *p<0.05 and **p<0.01 between PBS and HDM exposed mice or differences between Wt and Par-2 deficient mice.</p

The protease content in HDM is responsible for the IgE but not the IgG1 response.

<p>Allergic sensitization response after HDM exposure in Wt and Par-2 deficient mice. Total IgE, HDM-specific IgE and HDM-specific IgG1 ELISA measurements were performed in serum collected 24 hours after the last PBS/HDM exposure. Measurements of total IgE after PBS and (A) HDM Greer exposure or (B) HDM Citeq exposure, HDM-IgE after PBS and (C) HDM Greer exposure or (D) HDM Citeq exposure, HDM-IgG1 after PBS and (E) HDM Greer exposure or (F) HDM Citeq exposure. Median levels are shown (n = 6–8 mice per group). *p<0.05, **p<0.01 and ***p<0.001 between PBS and HDM exposed mice or between Wt and Par-2 deficient mice.</p

Par-2 deficiency affects IL-17 but not KC or IFNγ production after HDM exposure.

<p>ELISA measurements were performed in homogenized lung lysates from lungs collected 24/HDM exposure. Measurements of KC after PBS and (A) HDM Greer exposure or (B) HDM Citeq exposure, IL-17 after PBS and (C) HDM Greer exposure or (D) HDM Citeq exposure, and IFNγ after PBS and (E) HDM Greer exposure or (F) HDM Citeq exposure. Median levels are shown (n = 6–8 mice per group). *p<0.05 and **p<0.01 between PBS and HDM exposed mice.</p