von Willebrand factor-cleaving protease (VWFCP) in normal pregnancy

SÁNCHEZ LUCEROS, ANALÍA; FARÍAS, CRISTINA; AMARAL MARÍA M; KEMPFER, ANA C; CARBALLO GONZALO A; LAZZARI, MARÍA A

Bologna

Congreso; The 17th International Congress on Thrombosis; 2002

The dysfunction of VWFCP is an importantpathogenic risk factor for certain types of thrombotic microangipathies, there is Little information in physiological conditions. We studied the VWFCP activity in a cohort of 270 normal pregnant women. Mean age was 24.8 years old (14-41), 45.6% were primigravidae. All women were in good health, none had systemic diseases or abortion/fetal loss. The VWFCP was detected by dialysis with urea of Ba2+ activated purified VWF and plasma samples. The effect of VWFCP on VWF was determined by VWF:CB. VWF:Ag was performed by ELISA method using polyclonal antibody. The patients were divided according weeks of pregnancy: 6-11, 12-16, 17-23, 24-28, 29-35, 36-40 and early (up to 3 days) and late puerperium (7-20 days). The late postpartum showed the highest level of VWFCP activity, and without differences with no-pregnant women, so that it could be consider as the basal state of protease. It was observed a progressive decrease of VWFCP activity compared to the basal state, through pregnancy until early puerperium >0.001). Although this was the global tendency, the mean levels of protease were not different since 17 up to 40 weeks (Krsukal Wallis test). There was no significant correlation between protease levels and age, platelet count and VWF. There were no differences on VWFCP activities between O and no-O blood group. Up to 17 weeks, the primigravidaeVWFCP activities lower than multigravidae (p=0.006, Kruskal Wallis test). This is a noteworthy finding, considering that preeclampsia is most frequent in the first pregnancy. In summary, the VWFCP appears decline early on pregnancy (during the first trimester). The levels of VWFCP are different according to parity, up to 17 weeks at least. The establishment of this normal ranges may be useful to determine its value as early thrombotic microangiopathies marker during pregnancy.