FIG. 1.

Filaria-induced AHR in C57BL/6, IL-4^−/−, and IFN-γ^−/− mice. C57BL/6, IL-4^−/−, and IFN-γ^−/− mice were immunized three times s.c. with soluble B. malayi Ag. Ten days after the last immunization, mice were injected i.v. with 200,000 live Mf. AHR was measured as the force of tracheal smooth muscle contraction (in grams), with increased sensitivity to cholinergic agonists reflecting the severity of inflammation. Each data point represents the mean for eight mice combined from two experiments (standard deviations were <10%). P < 0.05 for C57BL/6 versus IFN-γ^−/− mice, and for C57BL/6 versus IL-4^−/− mice at 10⁻³ to 10⁻⁵ M ACh and carbachol.