title: Human platelet antigen antibody induction in uncomplicated pregnancy is associated with HLA sensitization.
abstract: BACKGROUND
  Alloimmunization against human platelet antigens (HPAs) during pregnancy is rare but can lead to severe bleeding disorders, such as fetal and neonatal alloimmune thrombocytopenia.
  
  
  METHODS
  In a cohort of 241 uncomplicated pregnancies, we investigated the immunogenicity of HPA mismatches and correlated HLA sensitization with HPA antibody formation. HPA antibodies were measured with a Luminex-based multiplex assay.
  
  
  RESULTS
  HPA mismatches were observed in 109 of 241 pregnancies (45%), but child-specific HPA antibodies were only found in two of 109 cases (2%), indicating a low immunogenicity. Only nine of 241 women (4%) had detectable HPA antibodies. HLA sensitization was identified as a strong and independent predictor for HPA antibody formation (hazard ratio, 10.2; 95% confidence interval, 1.8-193; p = 0.006), whereas the number of pregnancies was not.
  
  
  CONCLUSIONS
  Our observational data indicated a low immunogenicity of HPA and suggest that a broader immune response-inferred by HLA sensitization-is probably associated with HPA antibody induction.
authors.affiliation: Regional Blood Transfusion Service, Swiss Red Cross.
authors.forename: Viktoria S A
authors.initials: VSA
authors.lastname: Reiher
authors.affiliation: Transplantation Immunology and Nephrology, University Hospital Basel.
authors.forename: Gideon
authors.initials: G
authors.lastname: Hönger
authors.affiliation: Regional Blood Transfusion Service, Swiss Red Cross.|Division of Hematology, University Hospital Basel.
authors.forename: Laura
authors.initials: L
authors.lastname: Infanti
authors.affiliation: Division of Hematology, University Hospital Basel.
authors.forename: Jakob R
authors.initials: JR
authors.lastname: Passweg
authors.affiliation: Department for Obstetrics and Fetomaternal Medicine, University Hospital Basel, Basel, Switzerland.
authors.forename: Irene
authors.initials: I
authors.lastname: Hösli
authors.affiliation: Regional Blood Transfusion Service, Swiss Red Cross, Zürich, Switzerland.
authors.forename: Beat M
authors.initials: BM
authors.lastname: Frey
authors.affiliation: Regional Blood Transfusion Service, Swiss Red Cross, Zürich, Switzerland.
authors.forename: Christoph
authors.initials: C
authors.lastname: Gassner
authors.affiliation: Regional Blood Transfusion Service, Swiss Red Cross, Zürich, Switzerland.
authors.forename: Stefan
authors.initials: S
authors.lastname: Meyer
authors.affiliation: Regional Blood Transfusion Service, Swiss Red Cross.|Division of Hematology, University Hospital Basel.
authors.forename: Andreas S
authors.identifier: http://orcid.org/0000-0002-7942-6746
authors.initials: AS
authors.lastname: Buser
authors.affiliation: Regional Blood Transfusion Service, Swiss Red Cross.|Division of Hematology, University Hospital Basel.
authors.forename: Andreas
authors.initials: A
authors.lastname: Holbro
authors.affiliation: Transplantation Immunology and Nephrology, University Hospital Basel.
authors.forename: Stefan
authors.initials: S
authors.lastname: Schaub
mesh_terms: D000328:Adult; D000917:Antibody Formation / Q000276:immunology; D016824:Antigens, Human Platelet / Q000276:immunology*; D015331:Cohort Studies; D005260:Female; D006680:HLA Antigens / Q000276:immunology*; D054502:Histocompatibility, Maternal-Fetal; D006801:Humans; D011247:Pregnancy; D054098:Thrombocytopenia, Neonatal Alloimmune / Q000209:etiology
chemical_list: D016824:Antigens, Human Platelet; D006680:HLA Antigens