23] Molecular analysis of Streptococcus pyogenes adhesion

Abstract

This chapter presents a comprehensive strategy for the evaluation of known streptococcal surface proteins in adhesion to host cells and tissues. Central to the analyses is the construction of defined mutant strains that are defective in expression of the protein under analysis and the comparison of the mutant and wild-type strains in relevant in vitro models of adhesion. The in situ assay for adhesion to cells in tissue is ideal for the establishment of a defined interaction with a specific host cell or tissue. Once the host cell or tissue is identified, further analyses might utilize primary cultures of cells derived from the tissue that are representative of the target cell. The histological and biochemical characterization of adhesion to the cell in primary culture and the in situ assay may reveal the identity of the host-cell receptor, which can then be utilized to identify a clone expressing the adhesin in a genomic library of streptococcal DNA in Escherichia coli. The combination of receptor and adhesin identification and gene regulation studies proves to be rewarding in understanding the molecular pathogenesis of streptococcal infections and provide essential information for the development of novel therapeutic strategies to combat infection by Streptococcus pyogenes.