Heterogeneous in vivo expression of clumping factor A and capsular polysaccharide by Staphylococcus aureus: Implications for vaccine design

Wyeth Vaccine Research, 401 N. Middletown Road, Pearl River, NY 10965, USA.
Vaccine (Impact Factor: 3.49). 03/2009; 27(25-26):3276-80. DOI: 10.1016/j.vaccine.2009.01.062
Source: PubMed

ABSTRACT There is a clear unmet medical need for a vaccine that would prevent infections from Staphylococcus aureus (S. aureus). To validate antigens as potential vaccine targets it has to be demonstrated that the antigens are expressed in vivo. Using murine bacteremia and wound infection models, we demonstrate that the expression of clumping factor A (ClfA) and capsular polysaccharide antigens are heterogeneous and dependent on the challenge strains examined and the in vivo microenvironment. We also demonstrate opsonophagocitic activity mediated by either antigen is not impeded by the presence of the other antigen. The data presented in this report support a multiantigen approach for the development of a prophylactic S. aureus vaccine to ensure broad coverage against this versatile pathogen.

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    • "All S. aureus strains possess the genetic pathway for synthesis of either CP5 or CP8 [19]. Analysis of CP expression shows that although some strains do not express CP under in vitro growth conditions, CP expression is detected in vivo [20] [21]. ClfA is a well-conserved surface antigen that facilitates S. aureus infection by binding to fibrinogen, complement proteins, and platelets, thus mediating adhesion to host tissues [22]. "
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