Expression of CCR5 and CD4 on CHO.CCR5, CHO.CCR5.CD4, and HeLa RC49 cells.

Expression was determined using FACS analysis as described in “Materials and methods.” (A) FACS analysis for the expression of CCR5. Black, negative control; bold line, CHO.CCR5 cells; dotted line, CHO.CCR5.CD4 cells; thin line, HeLa RC49. (B) FACS analysis for expression of CD4. Black, negative control; dotted line, CHO.CCR5.CD4 cells; thin line, HeLa RC49.