METHODS: Samples were reacted with tissue factor (TF)/phospholipids and recombinant thrombomodulin (rTM; optimal 20 nM), followed by CWA measurement. The peak ratio (with/without rTM) of the first derivative curve of clot waveform was calculated.
RESULTS: The peak ratio in healthy plasmas (n = 35) was 0.36 ± 0.13; hence, the cutoff value was set to 0.49. The peak ratios in plasmas with PC deficiency, PS deficiency, high-FVIII (spiked 300 IU/dl), and APS were higher than the cutoff values (0.79/0.97/0.50/0.93, respectively). PC-deficient plasma or PS-deficient plasma mixed with normal plasma (25%/50%/75%/100% PC or PS level) showed dose-dependent decreases in the peak ratios (PC deficient: 0.85/0.64/0.44/0.28; PS deficient: 0.69/0.53/0.40/0.25), suggesting that the peak ratio at ≤50% of PC or PS level exceeded the cutoff value. The peak ratio in FV deficiency with FV ≤25% was higher than the cutoff value. FV-deficient plasma spiked with 40 IU/dl rFV-R506Q (FVLeiden ) or rFV-W1920R (FVNara ) showed >90% peak ratios.
CONCLUSIONS: rTM-mediated TF-triggered CWA might be useful for screening PC pathway abnormality-related thrombophilia.
方法:样品与组织因子(TF)/磷脂和重组血栓调节蛋白(rTM;最佳20nM)反应,其次是CWA测量。计算凝块波形的一阶导数曲线的峰比(有/没有rTM)。
结果:健康血浆中的峰比(n=35)为0.36±0.13;因此,截止值设置为0.49。PC缺乏的等离子体中的峰比,PS缺陷,高FVIII(峰值300IU/dl),和APS均高于临界值(分别为0.79/0.97/0.50/0.93)。PC缺乏血浆或PS缺乏血浆与正常血浆混合(25%/50%/75%/100%PC或PS水平)显示出峰比的剂量依赖性降低(PC缺乏:0.85/0.64/0.44/0.28;PS缺乏:0.69/0.53/0.40/0.25),表明PC或PS水平≤50%时的峰值比率超过了临界值。FV≤25%的FV缺乏症的峰值比率高于临界值。掺入40IU/dlrFV-R506Q(FVLeiden)或rFV-W1920R(FVNara)的缺乏FV的血浆显示>90%的峰比。
结论:rTM介导的TF触发的CWA可能用于筛查PC通路异常相关的血栓形成。