Fig. 4.
Screening semithin cryosections by immunofluorescence. Cryosections (0.5‐μm thick) from macrophages infected for 13 days with HIV‐1BaL were immunolabeled with a rabbit antiserum against HIV‐1 MA (UP595, provided by Dr. M. Malim, King's College London) and a monoclonal antibody against CD9 (mouse monoclonal anti‐CD9, Serotec, Kidlington, Oxford, UK), and the bound antibodies were detected with goat anti‐rabbit Alexa Fluor‐594 and goat anti‐mouse Alexa Fluor‐488 secondary antibodies (Invitrogen Molecular Probes, Paisley, UK). (A) Red fluorescence. MA staining reveals an accumulation of HIV viruses in one of the cells. (B) Green fluorescence. CD9 staining. (C) Merged image shows colocalization in yellow. Scale bar = 10 μm.