title: Monoclonal antibody 26 cross-reactive with β2-glycoprotein I affects human trophoblast invasion in vitro.
abstract: OBJECTIVE
  Monoclonal antibody 26 (MAb 26) raised against tetanus toxoid has documented cross-reactivity with β2-glycoprotein I. Passive introduction of this antibody in mice results in an antiphospholipid syndrome-like condition. We investigated the effects of MAb 26 on first trimester human trophoblast in vitro.
  
  
  METHODS
  Binding of MAb 26 to placental tissue trophoblast, isolated cytotrophoblast and HTR-8/SVneo cells was analyzed by immunohisto(cyto)chemistry. Possible effects on cell invasion in vitro were assessed by Matrigel assay. Effects on cell viability were assessed by MTT test. A possibility that MAb 26 induces change in levels of effector molecules important for cell invasion was investigated. Integrin subunits α1, α5 and β1, and galectin-1, were analyzed by qPCR and Western blot. Metalloproteinases -2 and -9 were assessed by gelatin zymography.
  
  
  RESULTS
  Immunohisto(cyto)chemistry showed binding of MAb 26 to placental tissue trophoblast, isolated cytotrophoblast and HTR-8/SVneo cells. The antibody had a significant inhibitory effect on cell invasion by both isolated cytotrophoblast and HTR-8/SVneo. The antibody induced significant decrease in protein levels of metalloproteinases, integrin subunit α1 and galectin-1. Cell viability was not affected.
  
  
  CONCLUSIONS
  MAb 26 reduces trophoblast invasion in vitro through decreased levels of metalloproteinases-2 and -9, integrin α1 and galectin-1.
authors.affiliation: Institute for the Application of Nuclear Energy - INEP, University of Belgrade, Serbia.
authors.forename: Tamara M
authors.initials: TM
authors.lastname: Kovačević
authors.forename: Ljiljana
authors.initials: L
authors.lastname: Radojčić
authors.forename: Nataša M
authors.initials: NM
authors.lastname: Tošić
authors.forename: Sonja T
authors.initials: ST
authors.lastname: Pavlović
authors.forename: Ljiljana M
authors.initials: LM
authors.lastname: Vićovac
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology / Q000378:metabolism*; D002460:Cell Line; D002465:Cell Movement / Q000187:drug effects* / Q000502:physiology; D002470:Cell Survival; D003429:Cross Reactions; D005260:Female; D037483:Galectin 1 / Q000378:metabolism; D006801:Humans; D051379:Mice; D011247:Pregnancy; D013745:Tetanus Toxoid / Q000276:immunology*; D014327:Trophoblasts / Q000276:immunology / Q000378:metabolism*; D053482:beta 2-Glycoprotein I / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D037483:Galectin 1; D013745:Tetanus Toxoid; D053482:beta 2-Glycoprotein I
keywords: Anti-tetanus toxoid; Anti-β(2)-glycoprotein I; Antiphospholipid syndrome; Trophoblast invasion