Researchers identify key behavior of immune response to Listeria

Oct 06, 2009

A team of University of British Columbia microbiologists has identified a key defence mechanism used by the immune system against Listeria with strong implications for the future development of vaccines.

Listeria is the bacteria that causes listeriosis, a food-borne infection that caused 22 deaths in Canada in an August 2008 outbreak in meat products produced by Maple Leaf Foods.

"We know a great deal about how our body's adaptive reacts to viruses but generally very little about immune response against bacterial infections," says Wilfred Jefferies, a professor at UBC's Michael Smith Laboratories and Biomedical Research Centre.

The study, published today in the online journal , focuses on dendritic cells that help activate the immune system. Dendritic cells collect pathogen materials and present them to other parts of the immune system - such as T-cells - a mechanism called cross-presentation.

The UBC team also includes post-doctoral fellows Anna Reinicke and Genc Basha and graduate student Kyla Omilusik.

" are gatekeepers; they are small in numbers but very active in patrolling tissues that are in contact with the external environment, such as the skin," says Jefferies, who is also a member of the UBC Blood Research Centre, the Brain Research Centre and the Vancouver Coastal Health Research Institute.

"Their job is to apprehend the pathogens while avoiding getting infected," says Jefferies. "We've found that they achieve this by
sampling bits and pieces of the bacterial pathogens in the area surrounding infected cells, instead of directly approaching the bacteria."

Their research also shows that when cross-presentation is deactivated, the host becomes severely compromised in its ability to generate the appropriate T-cells to fight the Listeria infection.

"This study establishes the vital role of dendritic cell cross-presentation in fighting bacteria infections and sheds light on how we can manipulate and engage immune responses. This knowledge will ultimately aid in the design of vaccines against bacteria and other pathogens," says Jefferies.

The study was supported by funding from The Canadian Institutes of Health Research (CIHR). "Better understanding of the body's immune system is the key to develop new strategies for treating bacterial infections and for creating new vaccines for Listeria ", says Dr. Bhagirath Singh, Scientific Director at CIHR's Institute of Infection and Immunity. "Dr. Jefferies's work advances our collective effort to prevent listerosis by focusing on the way our immune defences are wired and triggered upon initial infection by invading pathogens."

More information: The paper is available at dx.plos.org/10.1371/journal.pone.0007210

Source: University of British Columbia (news : web)

Explore further: Researchers capture picture of microRNA in action

add to favorites email to friend print save as pdf

Related Stories

New origin found for a critical immune response

Mar 01, 2009

An immune system response that is critical to the first stages of fighting off viruses and harmful bacteria comes from an entirely different direction than most scientists had thought, according to a finding by researchers ...

Researchers discover novel way to develop tumor vaccines

Mar 02, 2008

Researchers at the University of Southern California (USC) have uncovered a new way to develop more effective tumor vaccines by turning off the suppression function of regulatory T cells. The results of the study, titled ...

Recommended for you

Researchers capture picture of microRNA in action

13 hours ago

Biologists at The Scripps Research Institute (TSRI) have described the atomic-level workings of "microRNA" molecules, which control the expression of genes in all animals and plants.

Blocking a fork in the road to DNA replication

15 hours ago

A team of Whitehead Institute scientists has discovered the surprising manner in which an enigmatic protein known as SUUR acts to control gene copy number during DNA replication. It's a finding that could shed new light on ...

Cell division, minus the cells

18 hours ago

(Phys.org) —The process of cell division is central to life. The last stage, when two daughter cells split from each other, has fascinated scientists since the dawn of cell biology in the Victorian era. ...

A new method simplifies the analysis of RNA structure

18 hours ago

To understand the function of an RNA molecule, similar to the better-known DNA and vital for cell metabolism, we need to know its three-dimensional structure. Unfortunately, establishing the shape of an RNA ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.