Dynamic Ca2+ changes in neutrophil phagosomes. A source for intracellular Ca2+ during phagolysosome formation?
2000 (English)In: Cell Calcium, ISSN 0143-4160, Vol. 27, no 6, 353-362 p.Article in journal (Refereed) Published
An increase in cytosolic Ca2+ concentration periphagosomally is critical for phagolysosomal formation and neutrophil elimination of microbes. The Ca2+ increase could be achieved through release of Ca2+ from mobilized intracellular stores. Alternatively, Ca2+ that passively enter the phagosome during phagocytosis could be provided by the phagosome. Intraphagosomal Ca2+ changes in single human neutrophils was measured during phagocytosis of serum opsonized Fura-2-conjugated zymosan particles, using a digital image processing system for microspectrofluorometry. A decrease in phagosomal Ca2+ down to nanomolar concentrations was seen within minutes following phagosomal closure. Blockage of plasma membrane Ca2+ channels by econazole abolished this decrease. The fluorescence properties of Fura-2 zymosan were retained after phagocytosis and stable to pH changes, reactive oxygen species, and proteolytic enzymes. We suggest that Ca2+ ions present in the phagosome enter the cell cytosol through Ca2+ channels in the phagosomal membrane, achieving a localized Ca2+ rise that is important for phagosome processing.
Place, publisher, year, edition, pages
2000. Vol. 27, no 6, 353-362 p.
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-27858DOI: 10.1054/ceca.2000.0130Local ID: 12618OAI: oai:DiVA.org:liu-27858DiVA: diva2:248410