Open AccessHuman platelets efficiently kill I g G ‐opsonized E . coli
Author(s) -
Riaz Anum H.,
Tasma Brian E.,
Woodman Michael E.,
Wooten R. Mark,
Worth Randall G.
Publication year - 2012
Publication title -
fems immunology & medical microbiology
Language(s) - English
Resource type - Journals
eISSN - 1574-695X
pISSN - 0928-8244
DOI - 10.1111/j.1574-695x.2012.00945.x
Subject(s) - opsonin , platelet , microbiology and biotechnology , antibody opsonization , escherichia coli , phagocytosis , biology , immunoglobulin g , immunology , sepsis , antibody , biochemistry , gene
Platelets are known contributors of hemostasis but have recently been shown to be important in inflammation and infectious diseases. Moreover, thrombocytopenia is often observed in patients with sepsis. We previously reported that platelets actively phagocytosed I g G ‐coated latex beads. In this study, the capacity of human platelets to participate in host defense against bacterial infections was determined by assessing their ability to kill E scherichia coli . Washed human platelets were incubated with unopsonized or I g G ‐opsonized E . coli and evaluated for binding and killing of E . coli . We found that although both unopsonized and I g G ‐opsonized E . coli were associated with platelets, only I g G ‐opsonized E . coli were efficiently killed unless platelets were activated by a potent agonist. The bactericidal activity was dependent on F cγ RIIA , was sensitive to cytochalasin D , but was not due to reactive oxygen metabolites. These data suggest that platelets may play an important role in protection against infection.