Binding of ¹²⁵I-vWF to WT or M239V in the absence of inducers. Nontransfected (NT) medium was used as a control (□). Two hundred microliters of culture media from WT-transfected cells or M239V-transfected cells, containing equivalent amounts of GPIbα antigen, was immobilized onto a nitrocellulose membrane. After blocking, ¹²⁵I-vWF (0.15 μg/mL) was passed through the membranes and a bound radioactivity of each was assessed. Although no statistically significant ¹²⁵I-vWF binding could be shown to WT (), specific spontaneous binding of ¹²⁵I-vWF was observed to the mutant recombinant fragment M239V (▪; P < .01) and ¹²⁵I-vWF, and this binding was inhibited by an anti-vWF MoAb, NMC-4 (▨). This conclusion was based on the statistical analyses of 10 independent experiments of the same kind by the use of two-way layout ANOVA. However, the statistical results shown in this figure were the consequence of Bonferroni Post-Hoc test on 1 experiment that is representative of the 10 independent experiments. This analysis showed that only the column indicated (*) was significantly (P < .01) higher than the remaining five columns. Also, comparisons of ¹²⁵I-vWF binding to M239V in two different conditions [ie, NMC-4 (−) or (+)] showed that there was a statistically significant difference. However, no differences were demonstrated in the binding to NT [NMC-4 (−) or (+)] or to WT [NMC-4 (−) or (+)]. The results shown are the mean (±SD) of triplicate determinations.