Figure 5
From: Cholera toxin B suppresses allergic inflammation through induction of secretory IgA
Intrapulmonary administration of cholera toxin B (CTB) reduces allergic airway inflammation and bronchial hyperreactivity in already sensitized mice. Mice were ovalbumin (OVA)-sensitized by two injections of OVA/alum 1 week apart. At day 17, the mice were challenged by three OVA aerosols. Before each aerosol, the mice were intratracheally instilled with phosphate-buffered saline (PBS) or CTB. (a) BAL cell differential counts were determined by flowcytometry. (b) Mediastinal lymph node cells were cultured with OVA (10 mg/ml) for 4 days. Cytokine production was determined by enzyme-linked immunosorbent assay (ELISA) (c) At 1 day after challenge, bronchial hyperreactivity was measured by invasive measurements of dynamic airway resistance (Flexivent system) in response to increasing concentrations of intravenously administered methacholine (Sigma) during mechanical ventilation. (d) Chemokine production (TARC and MDC) in BAL supernatant was determined by ELISA. (e) Wild-type and pIgR−/− mice were OVA-sensitized. At day 17, the mice were PBS or OVA challenged. Before each aerosol, the mice were instilled with PBS or CTB. BAL cell differential counts were determined by flowcytometry. Data are mean±s.e.m, n=6 to 8 mice in each group. *P<0.05, **P<0.01, ***P<0.001. Data from one representative experiment out of two or three are shown.
