Immunofluorescence detection of nuclear translocation of the GR in xenografts ALL-3, ALL-7, ALL-16, and ALL-19. Xenograft cells were retrieved from cryostorage and exposed to dexamethasone (1 μM) for up to 4 hours prior to cytocentrifugation onto microscope slides and staining with GR antibody. GR was detected using Cy3-labeled secondary antibody (red), and slides were counterstained with DAPI to indicate nuclei (blue). Images were captured using a fluorescent microscope equipped with a cooled CCD camera, under a 63 × oil-immersion objective. Fields shown are representative of at least 5 imaged fields.