Radiolabeled Lp(a) binds with higher affinity than L-PLG to CHO cell surface TFPI.
(A) Left panel shows Western blot evidence of TFPI protein expression in CHO cells stably transfected with pcDNA3-TFPI plasmid compared to absent TFPI expression in parental nontransfected CHO cell line. Right panel shows specific binding of Lp(a) (5 nM) to CHO-TFPI cells compared to negligible binding of Lp(a) to a parental nontransfected CHO cell line. (B) Representative radioligand binding curves for Lp(a) and L-PLG to cell surface TFPI expressed on CHO-TFPI cells. (C) Apparent binding affinities (KD) and binding capacities (Bmax) of CHO cell surface TFPI for Lp(a) and L-PLG. Data presented are the means of at least 4 separate experiments performed in duplicate and the asterisk indicates P < .01.
