title: Gelatinase B/MMP-9 as an inflammatory marker enzyme in mouse zymosan peritonitis: comparison of phase-specific and cell-specific production by mast cells, macrophages and neutrophils.
abstract: Neutrophil infiltration during zymosan peritonitis depends on matrix metalloproteinase-9 (MMP-9) activity as it is impaired both in MMP-9(-/-) and gelatinase inhibitor-treated animals. The producer cells of MMP-9 and their relative contribution are not known. The aim of this study was to identify and compare the cellular sources, timing and intensity of MMP-9 induction by zymosan in the murine peritoneal cavity. We detected MMP-9 mRNA in unstimulated peritoneal leukocytes and its levels increased after zymosan administration. To detect MMP-9 by flow cytometry, we selected and compared two specific monoclonal antibodies. We show that MMP-9 protein was absent in control peritoneal macrophages, whereas already at 30min of peritonitis almost all macrophages were producing the enzyme. Conversely, MMP-9 was constitutively present in unstimulated mast cells. Macrophages turned out to be prevalent MMP-9 producers in the early phase of peritonitis. During later stages macrophages kept the high expression of MMP-9 for at least 6h of inflammation. In contrast, the early phase expression of MMP-9 by neutrophils was limited albeit the highest percentage of MMP-9(+) neutrophils was observed at 2h but absolute numbers of the MMP-9 carrying neutrophils were low at that time. In contrast, during the late phase of peritonitis neutrophils became major producers of MMP-9 as they numerously infiltrated peritoneum. In conclusion, the study reports detection of MMP-9 at the single-cell level during peritonitis, demonstrates unexpectedly fast MMP-9 expression in macrophages and reveals quantitatively phase-specific contribution of mast cells, macrophages and neutrophils.
authors.affiliation: Department of Evolutionary Immunobiology, Institute of Zoology, Jagiellonian University, ul. Ingardena 6, PL-30-060 Krakow, Poland. ela.kolaczkowska@uj.edu.pl
authors.forename: Elzbieta
authors.initials: E
authors.lastname: Kolaczkowska
authors.forename: Bernd
authors.initials: B
authors.lastname: Arnold
authors.forename: Ghislain
authors.initials: G
authors.lastname: Opdenakker
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000378:metabolism; D015415:Biomarkers / Q000378:metabolism; D015153:Blotting, Western; D004195:Disease Models, Animal; D008264:Macrophages / Q000276:immunology*; D008297:Male; D008407:Mast Cells / Q000276:immunology*; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D009504:Neutrophils / Q000276:immunology*; D010538:Peritonitis / Q000139:chemically induced / Q000175:diagnosis*; D015054:Zymosan
chemical_list: D000911:Antibodies, Monoclonal; D015415:Biomarkers; D015054:Zymosan; D020780:Matrix Metalloproteinase 9