In:
American Journal of Physiology-Gastrointestinal and Liver Physiology, American Physiological Society, Vol. 275, No. 4 ( 1998-10-01), p. G681-G688
Abstract:
The vacuolating toxin A (VacA) is one of the most important virulence factors in Helicobacter pylori-induced damage to human gastric epithelium. Using human gastric epithelial cells in culture and broth culture filtrate from a VacA-producing H. pylori strain, we studied 1) the delivery of VacA to cells, 2) the localization and fate of internalized toxin, and 3) the persistence of toxin inside the cell. The investigative techniques used were neutral red dye uptake, ultrastructural immunocytochemistry, quantitative immunofluorescence, and immunoblotting. We found that VacA 1) is delivered to cells in both free and membrane-bound form (i.e., as vesicles formed by the bacterial outer membrane), 2) localizes inside the endosomal-lysosomal compartment, in both free and membrane-bound form, 3) persists within the cell for at least 72 h, without loss of vacuolating power, which, however, becomes evident only when NH 4 Cl is added, and 4) generally does not degrade into fragments smaller than ∼90 kDa. Our findings suggest that, while accumulating inside the endosomal-lysosomal compartment, a large amount of VacA avoids the main lysosomal degradative processes and retains its apparent molecular integrity.
Type of Medium:
Online Resource
ISSN:
0193-1857
,
1522-1547
DOI:
10.1152/ajpgi.1998.275.4.G681
Language:
English
Publisher:
American Physiological Society
Publication Date:
1998
detail.hit.zdb_id:
1477329-6
SSG:
12
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