Studies of the release and turnover of a human neutrophil lipocalin.
A 24-kDa protein was purified from human neutrophil extracts and shown to be the newly discovered neutrophil gelatinase-associated lipocalin (NGAL), based on structural and immunochemical data. A specific enzyme-linked immunosorbent assay (ELISA) was developed for the determination of NGAL in human plasma and tissue fluids. Normal human plasma contains 72 micrograms l-1 of NGAL (range 40-109 micrograms l-1) in two main forms, monomer and dimer. 35S-methionine metabolic studies of human neutrophils showed that granulocyte macrophagecolony-stimulating factor (GMCSF) stimulated significant synthesis and secretion of NGAL in a dose- and time-dependent fashion. NGAL was rapidly released as monomer and dimer on incubation of heparinized whole blood with opsonized yeast, reaching a plateau corresponding to about 35% of total cell content after 30 min. Following intravenous injection of 125-iodine labelled NGAL there was a more rapid initial clearance of the monomeric than of the dimeric form; t1/2 10 min vs. 20 min. During the second phase the two forms cleared at similar rates. Severe acute peritonitis was accompanied by a 10-fold increase in NGAL plasma levels and the NGAL level in peritoneal exudates, which reached about 40 mg l-1. There was a good linear correlation between the concentrations of NGAL, leucocyte elastase and NP4 (neutrophil proteinase 4 = P3).
Axelsson
L
L
Department of Surgical Pathophysiology, University of Lund, Malmö University Hospital, Sweden.
Bergenfeldt
M
M
Ohlsson
K
K
D000208:Acute Disease; D000209:Acute-Phase Proteins; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000595:Amino Acid Sequence; D000818:Animals; D001202:Ascitic Fluid / Q000378:metabolism; D002352:Carrier Proteins / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology; D006207:Half-Life; D006801:Humans; D066298:In Vitro Techniques; D000071068:Lipocalin-2; D054834:Lipocalins; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009504:Neutrophils / Q000378:metabolism*; D015513:Oncogene Proteins; D010538:Peritonitis / Q000378:metabolism; D011518:Proto-Oncogene Proteins; D051381:Rats; D017208:Rats, Wistar; D012680:Sensitivity and Specificity
D000209:Acute-Phase Proteins; D002352:Carrier Proteins; C489506:LCN2 protein, human; D000071068:Lipocalin-2; D054834:Lipocalins; D015513:Oncogene Proteins; D011518:Proto-Oncogene Proteins; D016178:Granulocyte-Macrophage Colony-Stimulating Factor