title: Expression of granzyme B in peripheral blood polymorphonuclear neutrophils (PMN), myeloid cell lines and in PMN derived from haemotopoietic stem cells in vitro.
abstract: Granzyme B and perforin are the major protagonists of cytotoxicity mediated by natural killer (NK) cells or cytotoxic T cells. More recent we described the presence of granzyme B and perforin in polymorphonuclear neutrophils (PMN), a finding in discrepancy with the credo that granzyme B and perforin expression is restricted to cytotoxic T cells and NK cells. In extension of our previous study, we now provide evidence that granzyme B is not only present in mature PMN, but also in the myeloid cell lines HL-60 and U937, in CD34+ stem cells, and in PMN derived from CD34+ cells in vitro. In agreement with the "targeting by time" hypothesis we found the bulk of granzyme B in association with primary granules, in addition to a minor membrane expression. Granzyme B, on one hand might, enhance the cytotoxic potential of PMN, on the other, it may provide PMN with additional means to degrade extracellular matrices.
authors.affiliation: Institut für Immunologie der Universität Heidelberg, Im Neuenheimer Feld 305, 60120 Heidelberg, Germany.
authors.forename: Christof
authors.initials: C
authors.lastname: Wagner
authors.forename: Sabine
authors.initials: S
authors.lastname: Stegmaier
authors.forename: Gertrud Maria
authors.initials: GM
authors.lastname: Hänsch
mesh_terms: D018952:Antigens, CD34 / Q000378:metabolism; D002478:Cells, Cultured; D003594:Cytoplasmic Granules / Q000201:enzymology*; D053804:Granzymes / Q000097:blood / Q000378:metabolism*; D006801:Humans; D007694:Killer Cells, Natural / Q000201:enzymology*; D022423:Myeloid Cells / Q000201:enzymology; D009504:Neutrophils / Q000201:enzymology*; D013234:Stem Cells / Q000201:enzymology
chemical_list: D018952:Antigens, CD34; D053804:Granzymes