Acquisition of caveolin-2 by inclusions in caveolin-1 negative FRT cells.
(A) FRT cells were infected with chlamydial organisms for 48 h. C. pneumoniae, C. psittaci, and C. trachomatis serovars A, B, E, K (not shown), as well as serovars C and F colocalized with caveolin-2. MoPn and LGV (not shown), did not colocalize with caveolin-2 in these cells. Note that only two species, the mouse pneumonitis strain (MoPn) and GPIC produce large inclusions in these cells even after 48 h infection (scale bar is 25 μm). The small inclusions nonetheless release viable progeny into the culture supernatant which could be used to infect new cells. (B) Uninfected FRT-cells stained with anti-caveolin-2 antibody to demonstrate the localization of caveolin-2 protein in the cell. Note the caveolin-2 staining (C) close to the nucleus of the cell and that there is no caveolin in the cell membrane. (N), the nucleus of the cells and the scale bar represents 10 μm. Original magnification: 600X