Article ID Journal Published Year Pages File Type
3399196 Current Opinion in Microbiology 2012 8 Pages PDF
Abstract

Staphylococcus aureus causes purulent skin and soft tissue infections (SSTIs) that frequently reoccur. Staphylococal SSTIs can lead to invasive disease and sepsis, which are among the most significant causes of infectious disease mortality in both developed and developing countries. Human or animal infections with S. aureus do not elicit protective immunity against staphylococcal diseases. Here we review what is known about the immune evasive strategies of S. aureus that enable the pathogen's escape from protective immune responses. Three secreted products are discussed in detail, staphylococcal protein A (SpA), staphylococcal binder of immunoglobulin (Sbi) and adenosine synthase A (AdsA). By forming a complex with VH3-type IgM on the surface of B cells, SpA functions as a superantigen to modulate antibody responses to staphylococcal infection. SpA also captures pathogen-specific antibodies by binding their Fcγ portion. The latter activity of SpA is shared by Sbi, which also associates with complement factors 3d and factor H to promote the depletion of complement. AdsA synthesizes the immune signaling molecule adenosine, thereby dampening innate and adaptive immune responses during infection. We discuss strategies how the three secreted products of staphylococci may be exploited for the development of vaccines and therapeutics.

► Staphylococcus aureus causes recurrent infections without eliciting immunity. ► Escape from protective immunity involves staphylococcal spa, sbi and adsA genes. ► Interference of B cell development is blocked by antibodies against protein A (SpA). ► SpA and Sbi interfere with staphylococcal opsonophagocytic killing. ► Adenosine synthase (AdsA) dampens immune responses by providing a host signal.

Related Topics
Life Sciences Immunology and Microbiology Microbiology
Authors
, , , ,