title: Fluorescent labelling of intracellular bacteria in living host cells.
abstract: The fluorescent reagent, CellTracker, labels metabolically-active cells and was used here to label Chlamydia in vivo during their exponential phase of growth in infected cells. HeLa cells infected with C. psittaci were labelled with the CellTracker reagents between 15 and 48 h post-infection. The fluorescent label accumulated in the host-cell membrane compartment (inclusion) within which Chlamydia reside and replicate, and was also incorporated by the bacteria. Labelling with the CellTracker affected neither the growth nor the differentiation of the chlamydiae, and labelled chlamydiae isolated from infected cells were infectious. Our results demonstrate that the CellTracker could become a valuable tool for in vivo labelling of obligate intracellular parasites for which no genetic tools exist.
authors.affiliation: Unité de Biologie des Interactions Cellulaire, Institut Pasteur, URA CNRS 1960, 25 rue du Dr Roux, 75724, Paris, France. hboleti@mail.pasteur.gr
authors.forename: H
authors.initials: H
authors.lastname: Boleti
authors.forename: D M
authors.initials: DM
authors.lastname: Ojcius
authors.forename: A
authors.initials: A
authors.lastname: Dautry-Varsat
mesh_terms: D001422:Bacterial Adhesion; D001431:Bacteriological Techniques; D001896:Boron Compounds / Q000032:analysis; D002462:Cell Membrane / Q000737:chemistry / Q000382:microbiology; D002691:Chlamydophila psittaci / Q000254:growth & development* / Q000502:physiology; D005456:Fluorescent Dyes / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D008856:Microscopy, Fluorescence; D015336:Molecular Probe Techniques; D012235:Rhodamines / Q000032:analysis
chemical_list: C116572:(((4-chloromethyl)benzoyl)amino)-tetramethylrhodamine; C095489:4,4-difluoro-4-bora-3a,4a-diaza-s-indacene; D001896:Boron Compounds; D005456:Fluorescent Dyes; D012235:Rhodamines