title: The role of macrophages in the innate immune response to Streptococcus pneumoniae and Staphylococcus aureus: mechanisms and contrasts.
abstract: Macrophages are critical mediators of innate immune responses against bacteria. The Gram-positive bacteria Streptococcus pneumoniae and Staphylococcus aureus express a range of virulence factors, which challenge macrophages' immune competence. We review how macrophages respond to this challenge. Macrophages employ a range of strategies to phagocytose and kill each pathogen. When the macrophages capacity to clear bacteria is overwhelmed macrophages play important roles in orchestrating the inflammatory response through pattern recognition receptor-mediated responses. Macrophages also ensure the inflammatory response is tightly constrained, to avoid tissue damage, and play an important role in downregulating the inflammatory response once initial bacterial replication is controlled.
authors.affiliation: Department of Infection and Immunity, University of Sheffield Medical School and Sheffield Teaching Hospitals, Sheffield, United Kingdom.
authors.forename: Joby
authors.initials: J
authors.lastname: Cole
authors.affiliation: Department of Infection and Immunity, University of Sheffield Medical School and Sheffield Teaching Hospitals, Sheffield, United Kingdom.
authors.forename: Jody
authors.initials: J
authors.lastname: Aberdein
authors.affiliation: Department of Infection and Immunity, University of Sheffield Medical School and Sheffield Teaching Hospitals, Sheffield, United Kingdom.
authors.forename: Jamil
authors.initials: J
authors.lastname: Jubrail
authors.affiliation: Department of Infection and Immunity, University of Sheffield Medical School and Sheffield Teaching Hospitals, Sheffield, United Kingdom. Electronic address: d.h.dockrell@sheffield.ac.uk.
authors.forename: David H
authors.initials: DH
authors.lastname: Dockrell
mesh_terms: D000818:Animals; D006801:Humans; D007113:Immunity, Innate; D008262:Macrophage Activation; D008264:Macrophages / Q000166:cytology / Q000276:immunology*; D010587:Phagocytosis; D011008:Pneumococcal Infections / Q000276:immunology*; D013203:Staphylococcal Infections / Q000276:immunology*; D013211:Staphylococcus aureus / Q000235:genetics / Q000276:immunology*; D013296:Streptococcus pneumoniae / Q000235:genetics / Q000276:immunology*
keywords: Activation; Antimicrobicidal mechanisms; Macrophages; Pattern recognition receptors; Phagocytosis; Phagolysosomes; Staphylococcus aureus; Streptococcus pneumoniae