Extra-and intracellular Muc16 expression by MOVCAR cells. (A) MOVCAR-10 cells were labeled with 618F (grey line) and analyzed for cell surface expression of Muc16 by flow cytometry. Isotype control is shown by dark line. (B) MOVCAR-10 cells were fixed and expression of intracellular Muc16 was detected by using the 618F antibody (grey line). Dark line shows isotype control. (C) Expression of cell surface and intracellular Muc16 in the four MOVCAR cell lines was determined by flow cytometry using the 618 F antibody. The mean fluorescence intensity for the binding of 618F to the cell surface and intracellular Muc16 is plotted after subtracting the mean fluorescence intensity for the matched isotype controls. Each measurement is a mean of two independent experiments. (D) Same as in (C) except 653F was used for detection of murine Muc16.