title: PP13, maternal ABO blood groups and the risk assessment of pregnancy complications.
abstract: BACKGROUND
  Placental Protein 13 (PP13), an early biomarker of preeclampsia, is a placenta-specific galectin that binds beta-galactosides, building-blocks of ABO blood-group antigens, possibly affecting its bioavailability in blood.
  
  
  RESULTS
  We studied PP13-binding to erythrocytes, maternal blood-group effect on serum PP13 and its performance as a predictor of preeclampsia and intrauterine growth restriction (IUGR). Datasets of maternal serum PP13 in Caucasian (n = 1078) and Hispanic (n = 242) women were analyzed according to blood groups. In vivo, in vitro and in silico PP13-binding to ABO blood-group antigens and erythrocytes were studied by PP13-immunostainings of placental tissue-microarrays, flow-cytometry of erythrocyte-bound PP13, and model-building of PP13--blood-group H antigen complex, respectively. Women with blood group AB had the lowest serum PP13 in the first trimester, while those with blood group B had the highest PP13 throughout pregnancy. In accordance, PP13-binding was the strongest to blood-group AB erythrocytes and weakest to blood-group B erythrocytes. PP13-staining of maternal and fetal erythrocytes was revealed, and a plausible molecular model of PP13 complexed with blood-group H antigen was built. Adjustment of PP13 MoMs to maternal ABO blood group improved the prediction accuracy of first trimester maternal serum PP13 MoMs for preeclampsia and IUGR.
  
  
  CONCLUSIONS
  ABO blood group can alter PP13-bioavailability in blood, and it may also be a key determinant for other lectins' bioavailability in the circulation. The adjustment of PP13 MoMs to ABO blood group improves the predictive accuracy of this test.
authors.affiliation: First Department of Obstetrics and Gynecology, Semmelweis University, Budapest, Hungary. nthan@med.wayne.edu
authors.forename: Nandor Gabor
authors.initials: NG
authors.lastname: Than
authors.forename: Roberto
authors.initials: R
authors.lastname: Romero
authors.forename: Hamutal
authors.initials: H
authors.lastname: Meiri
authors.forename: Offer
authors.initials: O
authors.lastname: Erez
authors.forename: Yi
authors.initials: Y
authors.lastname: Xu
authors.forename: Federica
authors.initials: F
authors.lastname: Tarquini
authors.forename: Laszlo
authors.initials: L
authors.lastname: Barna
authors.forename: Andras
authors.initials: A
authors.lastname: Szilagyi
authors.forename: Ron
authors.initials: R
authors.lastname: Ackerman
authors.forename: Marei
authors.initials: M
authors.lastname: Sammar
authors.forename: Tibor
authors.initials: T
authors.lastname: Fule
authors.forename: Katalin
authors.initials: K
authors.lastname: Karaszi
authors.forename: Ilona
authors.initials: I
authors.lastname: Kovalszky
authors.forename: Zhong
authors.initials: Z
authors.lastname: Dong
authors.forename: Chong Jai
authors.initials: CJ
authors.lastname: Kim
authors.forename: Peter
authors.initials: P
authors.lastname: Zavodszky
authors.forename: Zoltan
authors.initials: Z
authors.lastname: Papp
authors.forename: Ron
authors.initials: R
authors.lastname: Gonen
mesh_terms: D000017:ABO Blood-Group System / Q000737:chemistry / Q000378:metabolism*; D000595:Amino Acid Sequence; D004912:Erythrocytes / Q000378:metabolism; D005260:Female; D005317:Fetal Growth Retardation / Q000097:blood / Q000175:diagnosis; D037161:Galectins / Q000097:blood* / Q000737:chemistry / Q000378:metabolism; D006630:Hispanic or Latino; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009035:Mothers; D011225:Pre-Eclampsia / Q000097:blood / Q000175:diagnosis; D011237:Predictive Value of Tests; D011247:Pregnancy; D011248:Pregnancy Complications / Q000097:blood* / Q000175:diagnosis* / Q000378:metabolism; D011257:Pregnancy Proteins / Q000097:blood* / Q000737:chemistry / Q000378:metabolism; D011487:Protein Conformation; D018570:Risk Assessment; D013379:Substrate Specificity; D044465:White People
chemical_list: D000017:ABO Blood-Group System; D037161:Galectins; C038195:LGALS13 protein, human; D011257:Pregnancy Proteins