Analysis of Staphylococcus aureus Gene Expression During PMN Phagocytosis - Bacterial Pathogenesis: Methods and Protocols - page 103

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Analysis of Staphylococcus aureus Gene Expression
During PMN Phagocytosis
Jovanka M. Voyich, Dan E. Sturdevant, and Frank R. DeLeo
Summary
Staphylococcus aureus is a leading cause of human infections worldwide and causes
a variety of diseases ranging in severity from mild to life-threatening. The ability of
S. aureus to cause disease is based in part on its ability to subvert the innate immune
system. Advances in genome-wide analysis of host-pathogen interactions have provided
the necessary tools to investigate molecular factors that directly contribute to S. aureus
pathogenesis. This chapter describes methods to analyze gene expression in S. aureus
during interaction with human neutrophils.
Key Words: Staphylococcus aureus ; neutrophil; polymorphonuclear leukocytes;
microarray; gene expression; Affymetrix; transcript.
1. Introduction
Polymorphonuclear leukocytes (PMNs or neutrophils) are key effectors of
the human innate immune response against bacteria and fungi. At sites of
infection, PMNs bind and ingest bacteria by a process known as phagocytosis
(1) . Phagocytosis of bacteria elicits production of reactive oxygen species and
enriches phagocytic vacuoles with peptide microbicides (2) . Although PMNs
kill most bacteria, pathogens such as group A Streptococcus and Staphy-
lococcus aureus have evolved means to avoid destruction by neutrophils
and thereby cause human disease (3,4,5,6) . These pathogens have multiple
virulence determinants that work in concert to promote infection. Until recently,