Open AccessMacrophage-derived LTB4 promotes abscess formation and clearance of Staphylococcus aureus skin infection in mice
Author(s) -
Stephanie Brandt,
Nathan Klopfenstein,
Soujuan Wang,
Seth Winfree,
Brian P. McCarthy,
Paul R. Territo,
Lloyd Miller,
C. Henrique Serezani
Publication year - 2018
Publication title -
plos pathogens
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.719
H-Index - 206
eISSN - 1553-7374
pISSN - 1553-7366
DOI - 10.1371/journal.ppat.1007244
Subject(s) - phagocyte , chemotaxis , leukotriene b4 , chemokine , microbiology and biotechnology , staphylococcus aureus , immunology , macrophage , innate immune system , biology , effector , ccl2 , abscess , phagocytosis , immune system , inflammation , receptor , in vitro , bacteria , biochemistry , genetics
The early events that shape the innate immune response to restrain pathogens during skin infections remain elusive. Methicillin-resistant Staphylococcus aureus (MRSA) infection engages phagocyte chemotaxis, abscess formation, and microbial clearance. Upon infection, neutrophils and monocytes find a gradient of chemoattractants that influence both phagocyte direction and microbial clearance. The bioactive lipid leukotriene B 4 (LTB 4 ) is quickly (seconds to minutes) produced by 5-lipoxygenase (5-LO) and signals through the G protein-coupled receptors LTB4R1 (BLT1) or BLT2 in phagocytes and structural cells. Although it is known that LTB 4 enhances antimicrobial effector functions in vitro , whether prompt LTB 4 production is required for bacterial clearance and development of an inflammatory milieu necessary for abscess formation to restrain pathogen dissemination is unknown. We found that LTB 4 is produced in areas near the abscess and BLT1 deficient mice are unable to form an abscess, elicit neutrophil chemotaxis, generation of neutrophil and monocyte chemokines, as well as reactive oxygen species-dependent bacterial clearance. We also found that an ointment containing LTB 4 synergizes with antibiotics to eliminate MRSA potently. Here, we uncovered a heretofore unknown role of macrophage-derived LTB 4 in orchestrating the chemoattractant gradient required for abscess formation, while amplifying antimicrobial effector functions.