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Requirement for labile Zn2+ in phagocytosis by murine macrophages
Author(s) -
Williams Miguel,
Kohler Jonathan E,
Blass Amy L,
Lederer James A,
Kelly Edward,
Soybel David I
Publication year - 2010
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.24.1_supplement.lb588
Subject(s) - phagocytosis , extracellular , intracellular , internalization , chemistry , bapta , macrophage , chelation , zinc , immune system , incubation , cytoplasm , microbiology and biotechnology , receptor , immunology , biology , biochemistry , in vitro , organic chemistry
Systemic Zn 2+ deficiency impairs the ability to fight infection. We hypothesized that one mechanism of immune dysfunction in the setting of Zn 2+ deficiency is impaired phagocytosis by macrophages. Methods RAW 264.7 murine macrophages were incubated for three hours with E. coli cell walls labeled with Vybrant and pHrodo fluorescent reporters. Co‐incubation occurred in the presence or absence of two intracellular Zn 2+ chelators (high affinity TPEN 10μM, low affinity BAPTA 10μM) and one extracellular zinc chelator (DTPA 10 μM). Confirmatory experiments were performed with mouse peritoneal macrophages. Results Intracellular zinc chelators caused reduced phagocytosis vs control (TPEN: 28% ± 8; BAPTA 54% ± 14%, p < 0.02, N = 5). In contrast, chelation of extracellular zinc with DTPA had no effect. Conclusion Free cytoplasmic Zn 2+ is required for effective internalization of extracellular bacterial particles by both cultured and primary murine macrophages. Under acute conditions, intracellular stores are sufficient to optimize function.