Kamiya S, Kai M, Ozawa A, Kobayashi H, Shirai T, Harasawa S, Miwa T
Department of Microbiology, Kyorin University School of Medicine, Mitaka, Japan.
Eur J Gastroenterol Hepatol. 1994 Dec;6 Suppl 1:S23-7.
We sought a good indicator cell line to use in detecting the vacuolating toxin produced by Helicobacter pylori and in examining the characteristics of the toxin.
Using five cell lines [baby hamster kidney (BHK-21), human amnion (FL), human uterine cancer (HeLa), rabbit kidney (RK-13) and African green monkey kidney (Vero)], cytotoxicity assays were performed with 33 H. pylori strains. To analyse the proteins produced by toxigenic and non-toxigenic strains, immunoblotting was done with the sera of patients with gastroduodenal diseases.
When RK-13, FL, Vero, BHK-21 and HeLa cells were used for the assay, 73, 61, 27, 27 and 21% of strains, respectively, were toxigenic. The vacuolating toxin is sensitive to heat at 70 degrees C. By immunoblot analysis, under non-denaturing conditions, immune sera recognized proteins with molecular weights of 600,000 and 500,000 in the toxigenic but not in the non-toxigenic strains.
H. pylori produces vacuolating toxin, which is a heat-sensitive protein at 70 degrees C and is easily detectable by cytotoxicity assay using the RK-13 cell line. Toxigenic H. pylori strains produce various proteins, including this toxin, which are recognized by sera from patients with gastroduodenal diseases.
