title: Maternal anti-protein Z antibodies in pregnancies complicated by pre-eclampsia, SGA and fetal death.
abstract: OBJECTIVE
  Low maternal plasma protein Z (PZ) concentrations were reported in patients with pre-eclampsia (PE), a small for gestational age (SGA) neonate, and a fetal demise (FD). Anti-protein Z antibodies (APZ-AB) have been proposed as a possible underlying mechanism leading to low plasma PZ concentrations. The objective of this study was to determine the maternal plasma concentration of APZ-AB in women with a normal pregnancy, and patients with PE, an SGA neonate or a FD.
  
  
  METHODS
  A cross-sectional study included women in the following groups: (1) non-pregnant women (n = 45); and pregnant women with: (2) normal pregnancies (n = 70); (3) PE (n = 123); (4) SGA neonates (n = 51); and (5) a FD (n = 51). Plasma concentrations of anti-protein Z IgM and IgG antibodies were measured by ELISA. Elevated APZ-AB was defined as >75th, 90th and 95th percentile of the normal pregnancy group. Non-parametric statistics were used for analyses.
  
  
  RESULTS
  (1) Patients with an SGA neonate had a higher median maternal plasma IgG APZ-AB concentration than women with normal pregnancies (p < 0.001), and patients with PE (p < 0.001) or with a FD (p = 0.001). (2) The proportion of patients with a maternal plasma IgM APZ-AB concentration >90th percentile was higher in the SGA group than in the PE group (p = 0.01). (3) Patients with PE maternal plasma IgM APZ-AB concentration >90th percentile had a higher rate of villous thrombosis (p = 0.03) and persistent muscularization of basal plate arteries (p = 0.01) than those with IgM APZ-AB concentration <90th percentile; and (5) Patients with FD and maternal plasma IgM APZ-AB concentration >90th percentile had a higher rate of umbilical phlebitis and arteritis than those with IgM APZ-AB concentration <90th percentile (p = 0.003).
  
  
  CONCLUSIONS
  (1) Patients with SGA neonates have a higher median plasma concentration of IgG APZ-AB than normal pregnant women, or patients with PE or FD; and (2) maternal plasma IgM APZ-AB concentration >90th percentile was associated with vascular placental lesions in patients with PE, but not in those with an SGA neonate, suggesting that in a subset of patients, these antibodies can be associated with abnormal placentation and pregnancy complications.
authors: Perinatology Research Branch, NICHD/NIH/DHHS, Bethesda, Maryland, USA.
authors: Offer
authors: O
authors: Erez
authors: Roberto
authors: R
authors: Romero
authors: Edi
authors: E
authors: Vaisbuch
authors: Shali
authors: S
authors: Mazaki-Tovi
authors: Juan Pedro
authors: JP
authors: Kusanovic
authors: Tinnakorn
authors: T
authors: Chaiworapongsa
authors: Nandor Gabor
authors: NG
authors: Than
authors: Francesca
authors: F
authors: Gotsch
authors: Chong Jai
authors: CJ
authors: Kim
authors: Pooja
authors: P
authors: Mittal
authors: Samuel
authors: S
authors: Edwin
authors: Percy
authors: P
authors: Pacora
authors: Sun Kwon
authors: SK
authors: Kim
authors: Lami
authors: L
authors: Yeo
authors: Moshe
authors: M
authors: Mazor
authors: Sonia S
authors: SS
authors: Hassan
mesh_terms: D000328:Adult; D001323:Autoantibodies / Q000097:blood*; D001798:Blood Proteins / Q000276:immunology*; D003430:Cross-Sectional Studies; D005260:Female; D005313:Fetal Death / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D007231:Infant, Newborn; D007236:Infant, Small for Gestational Age / Q000276:immunology*; D010920:Placenta / Q000098:blood supply; D011225:Pre-Eclampsia / Q000276:immunology*; D011247:Pregnancy; D014652:Vascular Diseases / Q000276:immunology
chemical_list: D001323:Autoantibodies; D001798:Blood Proteins; D007074:Immunoglobulin G; D007075:Immunoglobulin M; C026080:plasma protein Z