On the cover: Proteinase 3 protein (brown) was expressed in severely inflamed gingival epithelial cells surrounded by intercellular bridge, and strongly expressed in infiltrating segmented cells (the epithelial prickled cell layer of gingival tissue is shown), suggesting that the proteinase 3 could be a target Ag of antineutrophil cytoplasmic Abs. Uehara et al. Proinflammatory cytokines induce proteinase 3 as membrane-bound and secretory forms in human oral epithelial cells and antibodies to proteinase 3 activate the cells through protease-activated receptor-2. 4179.