H2O2 Release from Human Granulocytes during Phagocytosis

Histaminase release from human granulocytes

Histaminase (EC-1.4.3.6), one of the two catabolic enzymes for histamine, is contained in human granulocytes. Opsonized zymosan or the calcium ionophore A-23187 induce a dose-dependent release of histaminase from human granulocytes in vitro. Release is completed within 30 min, is temperature dependent, and requires divalent cations. Opsonized zymosan-induced histaminase release was maximal in t...

Mediators of histamine release from human platelets, lymphocytes, and granulocytes.

Lysates of mixed human leukocyte suspensions released histamine from intact human leukocytes in vitro. Microgram quantities of leukocyte lysate protein released up to 90% of the total available histamine. The mixed leukocyte lysates were separated by differential centrifugation into nuclear (800 g pellet), lysosomal (25,000 g pellet), and postlysosomal supernatant (25,000 g supernatant) fractio...

The Mobilization and Extracellular Release of Granular Enzymes from Human Leukocytes during Phagocytosis

The importance of granular (lysosomal) enzymes from neutrophils in producing the tissue damage of acute inflammation has been suggested by much indirect and some direct evidence. This study has investigated the kinetics of release and subsequent fate of granular enzymes from phagocytizing human leukocytes The following observations are made: (a) During phagocytosis, the granular enzyme lysozyme...

Phosphatidylserine externalization, “necroptotic bodies” release, and phagocytosis during necroptosis

Necroptosis is a regulated, nonapoptotic form of cell death initiated by receptor-interacting protein kinase-3 (RIPK3) and mixed lineage kinase domain-like (MLKL) proteins. It is considered to be a form of regulated necrosis, and, by lacking the "find me" and "eat me" signals that are a feature of apoptosis, necroptosis is considered to be inflammatory. One such "eat me" signal observed during ...

Relationship to Granule Release during Phagocytosis: Characterization and Chloride Movements in Human Neutrophils