vWf-dependent rfVIII accumulation in conditioned medium of transfected CHO cells.

CHO cells transfected with expression vectors for normal (•), Ile2098Ser (⧫), Ser2119Tyr (▪), and Arg2150His (▴) fVIII were incubated for 16 hours in the presence of various concentrations of vWf, as indicated. fVIII activity was determined in a chromogenic assay. Results were expressed as the ratio between fVIII:c levels in the presence of vWf to that in the absence of vWf. One representative experiment of 3 is shown.