HDM exposure increases sensitivity to methacholine.

<p>Adult female BALB/c mice were exposed to 25 μg of HDM protein (or control) daily for 10 days. On day 9 they were infected with 1×10⁸ TCID₅₀ HRV-1B or inactivated virus. Measurements were made 48 hours after infection. The dose of methacholine required to elicit a 150% increase in respiratory system resistance (B), tissue damping (C) and tissue elastance (H) was significantly lower in mice exposed to HDM compared to those not exposed to HDM. There was no effect of HRV-1B, or the combination of the two insults on sensitivity to MCh. * indicates a significant effect of HDM-exposure. <i>n</i> = 8 to 10 per treatment. Data are mean ± standard deviation.</p

Baseline lung function as measured by the forced oscillation technique of mice exposed to HDM, infected with HRV or both.

<p>a  =  effect of HDM, b  =  combined effect of HRV and HDM. Data are mean ± standard deviation.</p

Exacerbation of bronchoalveolar neutrophilia by the combination of HDM exposure and HRV-1B infection.

<p>Adult female BALB/c mice were exposed to 25 μg of HDM protein (or control) daily for 10 days. On day 9 they were infected with 1×10⁸ TCID₅₀ HRV-1B or inactivated virus. Samples were harvested 48 hours after infection. HDM exposure induced an increase in bronchoalveolar lavage total cells (A), macrophages (B) and neutrophils (C). HRV-1B infection alone increased total cellular inflammation (A). There was an additive effect of HDM exposure and HRV-1B infection on bronchoalveolar neutrophilia (C) * indicates a significant difference between groups. <i>n</i> = 8 to 10 per treatment. Data are mean ± standard deviation.</p

HDM exposure results in increased total IgE and HDM-specific IgG₁.

<p>Adult female BALB/c mice were exposed to 25 μg of HDM protein (or control) daily for 10 days. On day 9 they were infected with 1×10⁸ TCID₅₀ HRV-1B or inactivated virus. Samples were harvested 48 hours after infection. HDM exposure resulted in increased total IgE (A) and HDM-specific IgG₁ (B), however there were no effects of HRV-1B infection, or the combination of HDM exposure and HRV-1B infection on serum antibodies. * indicates a significant difference between groups. <i>n</i> = 8 to 10 per treatment. Data are mean ± standard deviation.</p

HDM exposure results in increased MIP-2 and decreased IFNα and IL-13.

<p>Adult female BALB/c mice were exposed to 25 μg of HDM protein (or control) daily for 10 days. On day 9 they were infected with 1×10⁸ TCID₅₀ HRV-1B or inactivated virus. Samples were harvested 48 hours after infection. HDM exposure increased bronchoalveolar lavage MIP-2 (A), and decreased IFNα (B) and IL13 (C). There was no effect of HDM exposure on BAL protein (D), nor were there any effects of HRV-1B infection alone, or combined effects of HDM exposure and HRV-1B infection on any of these parameters. * indicates a significant difference between groups. <i>n</i> = 8 to 10 per treatment. Data are mean ± standard deviation.</p