Bacterial phagosome acidification within IFN-gamma-activated macrophages: role of host p47 immunity-related GTPases IRGs).
Interferon-gamma IFN-gamma)-induced remodeling of the bacterial phagosome for pathogen clearance elicits the aid of a new family of GTPases termed the p47 IRGs. Members of this group reside primarily on ER-Golgi membranes before translocating to the nascent phagosome within minutes of bacterial uptake. Recruitment of p47 IRGs coincides with the acquisition of phagosome maturation and autophagy markers as well as enhanced acidification of this organelle. Here we describe a simple spectrofluorometric assay to measure luminal acidification of the bacterial phagosome within intact cells such as macrophages. This method can be applied to study the phagosomal pH pH_pg) of activated cells infected with a variety of infectious microorganisms and the roles played by members of the p47 IRG family in auto)phagolysosome biogenesis.
Tiwari
Sangeeta
S
Section of Microbial Pathogenesis, Yale University School of Medicine, Boyer Center for Molecular Medicine, New Haven, CT, USA.
Macmicking
John D
JD
D000818:Animals; D001419:Bacteria / Q000254:growth & development* / Q000276:immunology; D002478:Cells, Cultured; D020558:GTP Phosphohydrolases / Q000378:metabolism; D054884:Host-Pathogen Interactions; D007371:Interferon-gamma / Q000378:metabolism*; D008262:Macrophage Activation / Q000276:immunology; D008264:Macrophages / Q000166:cytology / Q000378:metabolism* / Q000382:microbiology; D051379:Mice; D010588:Phagosomes / Q000378:metabolism* / Q000382:microbiology; D013050:Spectrometry, Fluorescence
D007371:Interferon-gamma; D020558:GTP Phosphohydrolases; C491070:Iigp1 protein, mouse