FIG. 2.

Bax activation during infection with Chlamydia. (A) Bax activation was measured in HeLa cells by cytofluorimetry with the anti-Bax antibody (N-20). The dotted line represents the spectrum in the absence of N-20 antibody, the solid line corresponds to Bax staining in uninfected cells incubated with N-20 and FITC-conjugated second antibody, and filled spectrum shows Bax staining in cells infected for 48 h and incubated with N-20 and second antibody. Bax activation and intracellular distribution were also evaluated by confocal microscopy. Nuclei stained with Hoechst of uninfected HeLa cells (B) or cells infected with C. psittaci for 48 h (C), showing fragmenting nuclei in infected cells, are shown. The arrowhead indicates a Chlamydia inclusion. Subcellular localization of Bax (F) and mitochondria (D) in uninfected cells is shown. Subcellular localization of Bax (G) and mitochondria (E) in cells undergoing apoptosis in infected sample is also shown.