Identification of vaccine candidate antigens of Staphylococcus aureus by serological proteome analysis

Abstract

In this study we applied serological proteome analysis (Klade, C. S. et al. Proteomics 2001, 1, 890-898) for identification of bacterial vaccine candidate antigens. First, approximately one hundred sera from healthy individuals and patients suffering from Staphylococcus aureus infections were screened for antibodies against staphylococcal lysates and recombinant proteins representing surface antigens. Two pools (healthy donors, patients) each consisting of five sera with the highest antiproteinaceous IgG reactivity were selected. Second, S. aureus COL was grown under different conditions and the number of antigens expressed was monitored by Western blot analysis. Third, surface proteins were enriched by digesting the bacterial cell wall under isotonic conditions and subsequent removal of protoplasts. These protein preparations were resolved by two-dimensional electrophoresis (2-DE) (pI 4-7). 2-DE immunoblotting using the preselected serum pools at 1:10 000-1:100 000 dilutions revealed a number of highly immunogenic staphylococcal proteins. Twenty-one spots were isolated by preparative 2-DE, and analysed by matrix-assisted laser desorption/ionization mass spectrometry and tandem mass spectrometry sequencing of tryptic peptides. This led to the identification of 15 proteins including known and novel vaccine candidates. Seroreactivity of several antigens including serine-aspartate repeat containing protein D, immuno-dominant staphylococcal antigen and a novel 309 amino acid lipoprotein was independently confirmed by enzyme-linked immunosorbent assay and Western blot analysis of purified recombinant proteins. In conclusion, serological proteome analysis proved to be a powerful tool for the identification of novel staphylococcal antigens, which provide a basis for rational vaccine design.

Characterization of novel LPXTG-containing proteins of Staphylococcus aureus identified from genome sequences

“…SasI was also shown to be expressed during infection because sera from convalescent patients reacted with SasI peptides displayed on the surface of E. coli (Etz et al, 2002), while SdrD was identified by serological proteome analysis (Vytvytska et al, 2002).…”

Synthetic Peptide Vaccines

“…Now, highthroughput screening methods for antigen detection in microorganism proteomes have appeared. These include SERPA technology (SERological Proteome Analysis) and antigenome analysis (Klade, 2002;Ling et al, 2004;Tedeschi et al, 2009,Vytvytska et al, 2002, Målen et al, 2008Glowalla et al, 2009;Meinke et al, 2005;Felgner et al, 2009;Fritzer et al, 2010). The first method consists in the separation of protein components of the cultivated infectious agent by two-dimensional electrophoresis followed by subsequent visualization of antigenically active proteins by immunoblotting with antibodies from sera of patients with corresponding diseases (Målen et al, 2008;Glowalla et al, 2009;Meinke et al, 2005;Felgner et al, 2009;Fritzer et al, 2010).…”

Post‐genomic vaccine development

“…A total of 60 antigenic proteins were identified [46,47] Serological proteome analysis: A surface proteins preparation from S. aureus was resolved by 2D electrophoresis and analyzed in immunoblotting using two pools, each consisting of five sera coming from healthy donors or patients. Twenty-one spots were isolated analyzed in mass spectrometry allowing the identification of 15 proteins including known and new vaccine candidates [31] Porphyromonas gingivalis Periodontal pathogen that has been implicated in the etiology of chronic adult periodontitis…”

“…Recently, advances in protein separation technologies, combined with mass spectrometry and genome sequencing, have made the elucidation of total protein components of a given cellular population a feasible task [27][28][29]. Moreover, the combination of proteomics with serological analysis has recently led to the development of a new valuable approach defined as serological proteome analysis (SERPA) for the identification of in vivo immunogens suitable as vaccine candidates (Table 2, [30,31]). …”