C. pneumoniae growth inhibition by compound D7 is dose-dependent. A: compound D7 at 0.4 μM exhibited no inhibition of chlamydial growth (normal size inclusions), 2 μM exhibited partial inhibition (smaller inclusions), and 10 μM had a significant inhibitory effect (significantly reduced inclusion size) (bottom panels, left to right, respectively). DMSO controls at 0.004, 0.02, and 0.1% (top panels, left to right, respectively) did not restrict growth as indicated by inclusion size. Arrows indicate representative inclusions. B: Addition of 10 μM compound D7 to C. pneumoniae-infected HeLa cells at 1, 15 or 24 hpi resulted in small inclusions at 72 hpi. Inclusions were stained with FITC-conjugated anti-LPS monoclonal antibody containing Evan's Blue counterstain.