FACS analysis of HTK expression on cell lines with MoAb, 38-1E, against the extracellular domain of HTK. (A) UT-7 cells, (B) BaF3/HTK cells, and (C) BaF3/vector cells. The cells were stained with biotinylated 38-1E (solid lines) or biotinylated 38-1E that had been incubated with a 50-fold excess molar of HTKex-Fc (broken lines), followed by FITC-conjugated streptavidin. The dotted line indicates negative controls stained with FITC-conjugated streptavidin only.