In this study, we examined lymphocyte homing receptor and vascular addressin expression in a case of primary gastric B-cell lymphoma of mucosa- associated lymphoid tissue (MALT) with a secondary intestinal spread. We compared the findings with that observed in B cells of normal MALT and MALT acquired as a consequence of Helicobacter pylori-associated gastritis and other low-grade gastric B-cell MALT lymphomas. The neoplastic B cells in the gastric tumor were α4β7-, CD62L+, whereas the intestinal secondary was α4β7+, CD62L-. Incubation of isolated tumor cells from the stomach by H. pylori generated T-cell-dependent proliferation of neoplastic B cells and induced expression of α4β7 integrin similar to the in o testinal tumor. These observations indicate that reversal of homing receptor profile in the gastric tumor by antigen specific stimulation may be responsible for secondary intestinal dissemination. In normal stomach and normal MALT, α4β7 and CD62L expression reflected the differentiation of the B cell. Plasma cells were α4β7+, CD62L-, whereas a subset of memory B cells were α4β7+, CD62L+. Homing receptor expression in MALT lymphoma B cells was heterogeneous, however, in line with their memory B-cell phenotype in the majority of cases, the neoplastic B cells were α4β7-, CD62L+. Neoplastic plasma cells were always α4β7+, CD62L-. The venules in normal gastric mucosa expressed mucosal addressin cell adhesion molecule-1 but not peripheral lymph node addressin. In normal MALT, H. pylori-associated follicular gastritis and MALT lymphomas high endothelial venules coexpressed mucosal addressin cell adhesion molecule-1 and peripheral lymph node addressin. These findings suggest expression of lymphocyte homing receptors by B cells and vascular addressins by mucosal venules are similar in normal MALT and MALT lymphomas, and factors controlling normal mucosal B-cell traffic are also operational in MALT lymphomas.
|Original language||English (US)|
|Number of pages||9|
|Journal||American Journal of Pathology|
|State||Published - Nov 1 1997|
ASJC Scopus subject areas
- Pathology and Forensic Medicine