Detection of lactoferrin and myeloperoxidase release from single neutrophils by a protein A plaque assay.
A haemolytic plaque assay was adopted to detect release of lactoferrin and myeloperoxidase (MPO) from single neutrophils. Target erythrocytes coated with protein A were bound as a monolayer by poly-L-lysine to the surface of a plastic dish. Secreted lactoferrin and MPO induced plaque formation dependent on the reaction with complement and specific antiserum producing lysis of the protein-A-coated sheep red blood cells. Lactoferrin was found to be released spontaneously from a fraction of neutrophils while MPO was released only after phagocytosis, reflecting different mechanisms for degranulation of MPO-containing azurophil and lactoferrin-containing specific granules.
D000921:Antibody-Producing Cells / Q000276:immunology / Q000378:metabolism; D003165:Complement System Proteins; D006462:Hemolytic Plaque Technique; D006801:Humans; D007781:Lactoferrin / Q000276:immunology / Q000378:metabolism*; D007782:Lactoglobulins / Q000378:metabolism*; D009504:Neutrophils / Q000276:immunology / Q000378:metabolism*; D009195:Peroxidase / Q000276:immunology / Q000378:metabolism*; D010544:Peroxidases / Q000378:metabolism*; D010587:Phagocytosis; D013205:Staphylococcal Protein A
D007782:Lactoglobulins; D013205:Staphylococcal Protein A; D003165:Complement System Proteins; D010544:Peroxidases; D009195:Peroxidase; D007781:Lactoferrin