Figure 1.

Transglutaminase 2 (TG2) deficiency attenuates airway hypersensitivity. (A) Wild-type (WT) and TG2 deficient (TG2^−/−) mice were immunized with ovalbumin (OVA) plus aluminum hydroxide (alum) and intranasally challenged with OVA. (B) Immunohistochemistry of TG2 expression in the lungs from WT mice. Sections were prepared 24 h after intranasal OVA challenge (original magnification, ×400). (C) Representative photographs of lungs from WT and TG2^−/− mice after sensitization and challenge with PBS or OVA. Sections were stained with hematoxylin and eosin (original magnification, ×100). (D) Airway responsiveness was measured in sensitized and challenged mice. Pause was recorded for 3 min after aerosol methacholine treatment. The results for each group are expressed as means ± standard errors (n = 5).