Spatial and temporal separation of calcium signals in myeloid cells stimulated by immune complexes.
Stimulation of large (100 microns) human myeloid cells with immune complexes resulted in Ca2+ spiking. Both global and regional changes in the intracellular cytosolic free Ca2+ concentration were detected in response to immune complex stimulation. The regional changes were mediated by release of Ca2+ from stores, whereas global changes were mediated by Ca2+ influx. They occurred independently of each other, with release of Ca2+ from intracellular Ca2+ stores being separated from transmembrane influx of Ca2+. Bromophenacyl bromide, an 1-plastin binding agent, inhibited store release without preventing transmembrane influx of Ca2+. The large size of the myeloid cells used here allowed the visualisation of the spatial and temporal separation of store release from transmembrane influx of Ca2+, providing further evidence for the existence of independent Ca2+ store release and Ca2+ influx mechanisms in these cells.
Davies
E V
EV
Department of Surgery, University of Wales College of Medicine, Heath Park, Cardiff, U.K.
Roberts
G M
GM
Hallett
M B
MB
D000936:Antigen-Antibody Complex / Q000378:metabolism / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism*; D002478:Cells, Cultured; D003432:Cross-Linking Reagents / Q000378:metabolism; D005312:Fetal Blood / Q000166:cytology; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000737:chemistry / Q000166:cytology / Q000276:immunology*; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D011961:Receptors, Fc / Q000276:immunology; D015398:Signal Transduction / Q000187:drug effects / Q000276:immunology*
D000936:Antigen-Antibody Complex; D003432:Cross-Linking Reagents; D011961:Receptors, Fc; D009240:N-Formylmethionine Leucyl-Phenylalanine; D002118:Calcium