JMM Editor's Choice: Developing vaccines against Staphylococcus epidermidis

Posted on May 7, 2019   by Microbiology Society

The Journal of Medical Microbiology (JMM) is a journal published by the Microbiology Society, focused on providing a comprehensive coverage of medical, dental and veterinary microbiology and infectious diseases, including bacteriology, virology, mycology and parasitology. This month, ​​​​Dr Kim Hardie has selected an outstanding paper from the May issue to highlight as Editor's Choice. The paper, titled 'Synthesis of conjugated PIA-rSesC and immunological evaluation against biofilm-forming Staphylococcus epidermidis' discusses strategies researchers are using to develop a conjugate vaccine against S. epidermidis.

This manuscript describes data that could provide a promising approach to fight staphylococcal infections. The authors show that immunization of mice with a conjugate of polysaccharide intracellular adhesin (PIA) with the protein carrier rSesC increases the levels of opsonic antibodies leading to a better protection against Staphylococcus epidermidis

S. epidermidis is a leading cause of morbidity and premature mortality in patients with medical device-related infections, and this could therefore be of benefit to hospitalized patients.

Synthesis of conjugated PIA–rSesC and immunological evaluation against biofilm-forming Staphylococcus epidermidis

Bacteria are able to group together and form a protective layer known as a biofilm. If these biofilms form on the surface of medical devices, bacteria can spread to patients and cause infections such as sepsis. Staphylococcus epidermidis can easily contaminate medical devices and is capable of forming biofilms on both plastic and steel.

Polysaccharide intracellular adhesin (PIA) antibiodies have potential to eliminate S. epidermidis and prevent colonization on medical devices. The study found that immunizing mice with the carrier protein rSesC and PIA protected against wild-type S. epidermidis strain 1457. According to our findings, the immunization of high-risk patients with conjugate vaccine or treatment of them using monoclonal antibodies such as IgG2a could help to eradicate bacterial biofilms. The preparation and purification of specific anti-PIA IgG2a are a possible means to inhibit medical device infections caused by S. epidermidis and S. aureus.