Issues

Platelet-activating factor plays a dominant role in anaphylaxis. The lung from an ovalbumin-sensitized/challenged wild-type mouse displays airway constriction, airway epithelium folding, alveolar wall thickening, and alveolar distortion (top). In contrast, platelet-activating factor receptor–deficient mice show little anaphylactic symptoms in the lung (bottom). Hematoxylin and eosin staining and histologic analysis were performed by Dr. Takahide Nagase, Department of Geriatrics, The University of Tokyo, Tokyo, Japan. See related article in this issue by Ishii et al., pp. 1779–1788.