Clostridium difficile, the causative agent of antibiotic-associated pseudomembranous colitis, produces two toxins, A and B (1). Toxin A is both an enterotoxin and cytotoxin, whereas toxin B is a highly potent cytotoxin (2,3,4). Toxin A has been cloned and sequenced by our research team (5) and later by Sauerborn and von Eichel-Streiber (6). The entire coding region of toxin B and 398 bp of the ...

The genotypes of 78 strains of Helicobacter pylori from Calcutta, India (55 from ulcer patients and 23 from more-benign infections), were studied, with a focus on putative virulence genes and neutral DNA markers that were likely to be phylogenetically informative. PCR tests indicated that 80 to 90% of Calcutta strains carried the cag pathogenicity island (PAI) and potentially toxigenic vacAs1 a...

A bacterial agglutination assay, a toxin-neutralizing assay, and an enzyme-linked immunosorbent assay (ELISA) were used to compare antibodies against intestinal Aeromonas strains in serum samples from healthy carriers (n = 6), from patients with acute (n = 15) or chronic (n = 8) gastroenteritis, from patients with gastroenteritis caused by other enteropathogenic bacteria (n = 3), and from healt...

The Shiga toxigenic Escherichia coli (STEC) O113:H21 strain 98NK2, which was responsible for an outbreak of hemolytic uremic syndrome, secretes a highly potent and lethal subtilase cytotoxin that is unrelated to any bacterial toxin described to date. It is the prototype of a new family of AB 5 toxins, comprising a single 35-kilodalton (kD) A subunit and a pentamer of 13-kD B subunits. The A sub...

BACKGROUND IL-13 receptor (IL-13R) targeted cytotoxin, IL13-PE38QQR, has been shown to have very potent anti-tumor activity to IL-13R-expressing head and neck tumor cells in vitro and in vivo. However, its effect is limited in aggressive tumors. To further improve the anti-tumor activity and safety of IL-13 cytotoxin, we employed continuous infusion technique in animal model of head and neck ca...

Objective(s): Helicobacter pylori, a human specific gastric pathogen is a causative agent of chronic active gastritis. The vacuolating cytotoxin (VacA) is an effective virulence factor involved in gastric injury. The aim of this study was to construct a recombinant protein containing antigenic region of VacA gene and determine its antigenicity.   Materials and Methods: The antigenic region of V...

A quantitative assay for Clostridium difficile cytotoxin has been developed, based on the observation that suspended fibroblasts exposed to cytotoxin fail to adhere to plastic. A dye-binding technique was used to quantitate adherent cells, in order to obviate microscopy. Adherent BHK cells were fixed with glutaraldehyde and cell protein was stained with Coomassie blue R-250. Cell-bound dye was ...

The Shiga toxigenic Escherichia coli (STEC) O113:H21 strain 98NK2, which was responsible for an outbreak of hemolytic uremic syndrome, secretes a highly potent and lethal subtilase cytotoxin that is unrelated to any bacterial toxin described to date. It is the prototype of a new family of AB 5 toxins, comprising a single 35-kilodalton (kD) A subunit and a pentamer of 13-kD B subunits. The A sub...

BACKGROUND VacA and CagA proteins have been reported to be major virulence factors of Helicobacter pylori. However, antibodies against these proteins are frequently found in the sera of Japanese patients regardless of their gastroduodenal status. AIM To evaluate the expression of VacA and CagA proteins by H pylori strains isolated in Japan. METHODS By using specific antibodies raised agains...