Staphylococcus aureus: Why it just gets up your nose

December 27, 2012

A collaboration between researchers at the School of Biochemistry and Immunology and the Department of Microbiology at Trinity College Dublin has identified a mechanism by which the bacterium Staphylococcus aureus (S. aureus) colonizes our nasal passages. The study, published today in the Open Access journal PLOS Pathogens, shows for the first time that a protein located on the bacterial surface called clumping factor B (ClfB) has high affinity for the skin protein loricrin.

S. aureus is a major , with the potential to cause severe invasive diseases. It is a major cause for concern in hospitals and healthcare facilities, where many infections are caused by strains resistant to commonly used antibiotics [MRSA]. Interestingly, S. aureus persistently colonizes about 20% of the human population by binding to skin-like cells within the . Being colonized predisposes an individual towards becoming infected so it is vital that we understand the mechanisms involved.

ClfB was previously shown to promote S. aureus colonization in a human nasal colonization volunteer study. This paper now identifies the mechanism by which ClfB facilitates S. aureus nasal colonization. Purified ClfB bound loricrin with high affinity and this interaction was shown to be crucial for successful colonization of the nose in a mouse model. A lacking loricrin in its skin cells allowed fewer to colonize its nasal passages than a normal mouse. When S. aureus strains that lacked ClfB were used nasal colonization could not be achieved at all. Finally it was shown that soluble loricrin could reduce binding of S. aureus to human nasal skin cells and that nasal administration of loricrin reduced S. aureus colonization of mice.

Rachel McLoughlin, the study's corresponding author and Lecturer at the School of Biochemistry and Immunology at Trinity College Dublin concludes, "Loricrin is a major determinant of S. aureus nasal colonization." This discovery therefore opens new avenues for developing therapeutic strategies to reduce the burden of nasal carriage and consequently infections with this bacterium. This is particularly important given the difficulties associated with treating MRSA infections.

More information: Mulcahy ME, Geoghegan JA, Monk IR, O'Keeffe KM, Walsh EJ, et al. (2012) Nasal Colonisation by Staphylococcus aureus Depends upon Clumping Factor B Binding to the Squamous Epithelial Cell Envelope Protein Loricrin. PLOS Pathog 8(12): e1003092. doi:10.1371/journal.ppat.1003092

Related Stories

Coffee and tea consumption reduce MRSA risk

July 15, 2011

While an apple a day may keep the doctor away, new research published in the Annals of Family Medicine say that hot tea or coffee may keep the methicillin-resistant Staphyloccus aureus, or MRSA, bug away, or at least out ...

MRSA skin infections up, linked to furunculosis

July 27, 2012

(HealthDay) -- The incidence of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) in the United States is increasing and is associated with follicular infection, most commonly folliculitis followed ...

Recommended for you

Experimental MERS vaccine shows promise in animal studies

July 28, 2015

A two-step regimen of experimental vaccines against Middle East respiratory syndrome (MERS) prompted immune responses in mice and rhesus macaques, report National Institutes of Health scientists who designed the vaccines. ...

Can social isolation fuel epidemics?

July 21, 2015

Conventional wisdom has it that the more people stay within their own social groups and avoid others, the less likely it is small disease outbreaks turn into full-blown epidemics. But the conventional wisdom is wrong, according ...

Lack of knowledge on animal disease leaves humans at risk

July 20, 2015

Researchers from the University of Sydney have painted the most detailed picture to date of major infectious diseases shared between wildlife and livestock, and found a huge gap in knowledge about diseases which could spread ...

IBD genetically similar in Europeans and non-Europeans

July 20, 2015

The first genetic study of inflammatory bowel disease (IBD) to include individuals from diverse populations has shown that the regions of the genome underlying the disease are consistent around the world. This study, conducted ...

0 comments

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.