Researchers find link to severe Staph infections

Dec 23, 2008

Researchers at The University of Texas School of Public Health recently described studies that support the link between the severity of community-acquired antibiotic-resistant Staphylococcus aureus (CA MRSA) infections and the Panton Valentine leukocidin (PVL).

The Panton Valentine leukocidin is made up of two components - LukF-PV and LukS-PV - and is typically produced by community-acquired methicillin-resistant S. aureus (CA MRSA). In the United States this strain is the most common CA MRSA isolate and can cause severe skin infections, pneumonia, bloodstream infections and surgical wound infections.

This work has identified using animal models that the PVL leukotoxin can be used as a vaccine against infections caused by CA MRSA. Results from the research will be published in the December issue of Clinical Microbiology and Infection.

According to the Centers for Disease Control and Prevention, the antibiotic-resistant USA300 CA MRSA strain is typically acquired by persons through contact with the bacteria. This Staph strain is not typically associated with hospitalizations or medical procedures.

Eric Brown, Ph.D., assistant professor of infectious diseases at the UT School of Public Health and colleagues also tested the virulence of PVL in CA MRSA by using clinical strains of USA300 that did and did not contain the pore-forming toxin.

"The bacteria is not the same as it was several years ago. It has all of the weapons and toxins that other strains don't have, which makes it easier for this strain to survive efficiently inside of cells," Brown said.

"Immunity directed against LukS was more efficient in protecting mice against a USA300 infection compared to mice vaccinated with LukF-PV or alpha toxin," Brown said. His research found that LukS-PV was effective at protecting against certain types of infections reinforcing the importance of this virulence factor in the disease process. LukS-PV given through the nose protected the mice against pneumonia, conversely if administered subcutaneously it protected against skin infections.

Brown said, "The [vaccination] route and infection routes correlated with each other i.e., intranasally-immunized mice were better protected against pneumonia than subcutaneously vaccinated mice and subcutaneously-vaccinated mice were better protected against a skin infection than against pneumonia. This in part may be related to the type of immune response generated at the skin compared to the lung."

In addition, Brown and colleagues have examined the anti-PVL antibody responses in pediatric patients diagnosed with Staph infections compared to antibody responses to other USA300 virulence factors. The study found patients who had Staph infections caused by PVL-positive strains had a dominant response to the LukS and LukF proteins.

Source: University of Texas at Houston

Explore further: US orders farms to report pig virus infections

add to favorites email to friend print save as pdf

Related Stories

'Nanosponge vaccine' fights MRSA toxins

Dec 01, 2013

Nanosponges that soak up a dangerous pore-forming toxin produced by MRSA (methicillin-resistant Staphylococcus aureus) could serve as a safe and effective vaccine against this toxin. This "nanosponge vaccin ...

Recommended for you

US orders farms to report pig virus infections

1 hour ago

The U.S. government is starting a new program to help monitor and possibly control the spread of a virus that has killed millions of pigs since showing up in the country last year.

Foreigner dies of MERS in Saudi

2 hours ago

A foreigner has died after she contracted MERS in the Saudi capital, the health ministry said on announced Friday, bringing the nationwide death toll to 73.

Vietnam battles fatal measles outbreak

5 hours ago

Vietnam is scrambling to contain a deadly outbreak of measles that has killed more than 100 people, mostly young children, and infected thousands more this year, the government said Friday.

User comments : 0

More news stories

LinkedIn membership hits 300 million

The career-focused social network LinkedIn announced Friday it has 300 million members, with more than half the total outside the United States.

Magnitude-7.2 earthquake shakes Mexican capital

A powerful magnitude-7.2 earthquake shook central and southern Mexico on Friday, sending panicked people into the streets. Some walls cracked and fell, but there were no reports of major damage or casualties.

Sun emits a mid-level solar flare

The sun emitted a mid-level solar flare, peaking at 9:03 a.m. EDT on April 18, 2014, and NASA's Solar Dynamics Observatory captured images of the event. Solar flares are powerful bursts of radiation. Harmful ...