Fig. 7. CA125-C-TERM is transported to the cell surface of both CHO and HeLa cells as determined by confocal microscopy. CHO_MCAT-TAM2 and HeLa_MCAT-TAM2 cells, respectively, were grown on glass cover slips followed by transduction with retroviral particles encoding CA125-C-TERM or with retroviral control particles that lack a cDNA insert in the viral genome. After 3 days of incubation at 37°C, the cells were fixed with paraform aldehyde. Specimens shown in A-D represent CHO_MCAT-TAM2 cells that were not permeabilized to visualize exclusively cell-surface-localized CA125-C-TERM. Specimens shown in E-H represent Triton X-100-permeabilized HeLa_MCAT-TAM2 cells to detect intracellular CA125-C-TERM. CA125-C-TERM was visualized with the mAb OC125 (A, B, E-H). The Golgi marker p27 was detected with a polyclonal rabbit antiserum directed against a synthetic peptide that corresponds to the cytoplasmic tail of p27 (C and D) (Jenne et al., 2002). Double staining was performed using secondary antibodies coupled to Alexa-488 and Alexa-546, respectively. Specimens were analyzed with a Zeiss LSM510 confocal microscope.