Protective immunization of mice with an active-site mutant of subtilase cytotoxin of Shiga toxin-producing Escherichia coli
Date
2005
Authors
Talbot, U.
Paton, J.
Paton, A.
Editors
Advisors
Journal Title
Journal ISSN
Volume Title
Type:
Journal article
Citation
Infection and Immunity, 2005; 73(7):4432-4436
Statement of Responsibility
Ursula M. Talbot, James C. Paton, and Adrienne W. Paton
Conference Name
Abstract
We have recently described a novel AB5 cytotoxin produced by certain Shiga toxin-producing Escherichia coli strains. The A subunit of this toxin is a subtilase-like serine protease, while the B pentamer mediates binding to host cell glycolipid receptors. The subtilase cytotoxin is lethal for mice, causing extensive microvascular thrombosis as well as necrosis in the brain, kidneys, and liver. In the present study, we have immunized mice with a purified derivative of the toxin with a Ser272 Ala mutation in the A subunit which abolishes cytotoxicity. This elicited strong antibody responses, as judged by enzyme-linked immunosorbent assay, which conferred protection against intraperitoneal challenge with purified toxin. Immunized mice were also protected from weight loss resulting from oral challenge with an E. coli K-12 clone expressing the active toxin.