((([(MFI   of   cells   with   Ab-FITC   and   uncojugated   AB-MFI   of   cells   without   Ab-FITC   or   unconjugated   Ab)]*100))/(((MFI   of   cells   with   Ab-FITC   and   isotype   control-MFI   of   cells   without   Ab-FITC   or   unconjugated   Ab))))