Anti-virulence factor in Salmonella discovered
Researchers at the University of British Columbia have discovered an anti-virulence factor in Salmonella, providing knowledge that could be used to design improved Salmonella vaccines.
Virulence factors allow a pathogen to thrive in the host and cause disease. An anti-virulence factor controls the degree of infectiveness.
The finding, published in Public Library of Science, suggests that there is a distinct pathway in Salmonella that acts as an anti-virulence factor during salmonellosis. This pathway is also involved in fine-tuning the host-pathogen balance during salmonellosis.
The research demonstrates that the pathway is activated prior to ingestion and entry into the intestine and then shut off once Salmonella penetrates the intestine.
â€œWhen the anti-virulence factor is knocked out Salmonella becomes up to 10 times more virulent,â€ says Brett Finlay, Peter Wall Prof. of Microbiology and Biochemistry at UBC and senior investigator at the Michael Smith Laboratories. â€œThe research also demonstrates that Salmonella has the ability to control its virulence even before it enters the host.â€
â€œThe pathway is designed to initially control the level of virulence and not kill the host immediately,â€ says Finlay. â€œTapering the level of infectiveness allows Salmonella to establish itself in the host and then become more virulent.â€
â€œThis research will allow us to design improved salmonella vaccines,â€ says Finlay. â€œWe will be able to better tailor the vaccine strain with the appropriate level of virulence.â€