Disappearance of HEV-like vessels in the gastric mucosa after eradication of H. pylori. Gastric mucosa infected with H. pylori was examined before and 2 months after treatment to eradicate H. pylori. (A) Before treatment, HEV-like vessels detected by MECA-79 and HECA-452 antibodies were abundant, and large numbers of mononuclear cells (lymphocytes) were present around these vessels. (B) After eradication of H. pylori, HEV-like vessels were no longer present and very few mononuclear cells were present. CD34 was used for a marker of vascular endothelial cells. HE, hematoxylin and eosin, Bar = 100 μm. Adapted with permission from Kobayashi, M.; Mitoma, J.; Nakamura, N.; Katsuyama, T.; Nakayama, J.; Fukuda, M. Proc. Natl. Acad. Sci. USA, 2004, 101(51), 17807–17812, Copyright 2004 National Academy of Science, USA.