PATTERN OF ADHESION MOLECULE EXPRESSION ON VASCULAR ENDOTHELIUM IN HELICOBACTER-PYLORI-ASSOCIATED ANTRAL GASTRITIS

Background & Aims: The inflammatory response in Helicobacter pylori-as sociated gastritis (HAG) is characterized by an intense infiltrate of granulocytes and lymphocytes. The emigration of white blood cells into sites of inflammation is mediated by receptors on endothelial cells a nd on blood leukocytes. The aim of this study was to characterize endo thelial adhesion molecule expression in HAG leading to leukocyte infil tration. Methods: Endothelially expressed adhesion molecules were stud ied in situ by immunohistochemical analysis of antral mucosal biopsy s pecimens from 20 control patients, 10 of whom had chemical gastritis, 10 normal mucosa, and 44 HAG. Adjacent biopsies were used to evaluate messenger RNA (mRNA) transcripts for the respective adhesion molecule and its inducing cytokines, Results: Constitutive expression of P-sele ctin was found in all groups, Intercellular adhesion molecule 1 (ICAM- 1) was up-regulated in patients with HAG and chemical gastritis in con trast to normal controls. Vascular adhesion molecule 1 (VCAM-1) was on ly found within lymphoid aggregates present in HAG, Neither mRNA trans cripts nor the protein product of E-selectin were detected in normal o r inflamed mucosa, although mRNA of the E-selectin-inducing cytokines, tumor necrosis factor a and interleukin 1 beta, were found, Conclusio ns: Data suggest a major role of ICAM-1 and VCAM-1 in leukocyte-endoth elial interaction in HAG without E-selectin up-regulation showing a un ique pattern within the gastrointestinal tract, in contrast to observa tions made in inflammatory bowel disease.