A murine monoclonal antibody (RV3-27) raised against isolated human placental endogenous retroviral particles and reactive with syncytiotrophoblast

J Reprod Immunol. 1994 Mar;26(2):75-95. doi: 10.1016/0165-0378(94)90033-7.

Abstract

Particles with the characteristic shape of enveloped retroviral particles and maximal specific reverse transcriptase (RTase) activity at buoyant density of 1.15-1.17 g/ml have been isolated from human first-trimester chorionic villous tissue. Murine monoclonal antibodies (mAbs) to these isolated particles were generated. One IgM mAb (RV3-27) showed granular staining of cytoplasmic structures within syncytiotrophoblast by immunohistochemistry. Immunoelectron microscopic studies have demonstrated focal localisation to small submembranous regions of syncytiotrophoblast, as well as reaction with detergent-disrupted isolated placental retroviral-like particles. The RV3-27 mAb did not stain other human tissues in this focal manner, although increased generalised cytoplasmic staining was not uncommon; also, this mAb did not react strongly with the surface or cytoplasm of a variety of human cell lines (including choriocarcinoma cells). Immunoblotting and HPLC analyses have indicated the reactive placental antigen to be a 17-25 kDa protein. It is suggested that the RV3-27 mAb may be reactive with a syncytiotrophoblast antigen encoded by an endogenous retroviral sequence.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Monoclonal / immunology*
  • Antibodies, Viral / immunology*
  • Choriocarcinoma / pathology
  • Choriocarcinoma / virology
  • Chorionic Villi / virology*
  • Extraembryonic Membranes / immunology
  • Female
  • Humans
  • Immunoglobulin M / immunology
  • Immunologic Techniques
  • Mice
  • Mice, Inbred BALB C
  • Microscopy, Electron
  • Neoplasms / pathology
  • Organ Specificity
  • RNA-Directed DNA Polymerase / analysis
  • Retroviridae / enzymology
  • Retroviridae / immunology
  • Retroviridae / isolation & purification*
  • Retroviridae / ultrastructure
  • Trophoblasts / immunology*
  • Trophoblasts / virology
  • Tumor Cells, Cultured
  • Uterine Neoplasms / pathology
  • Uterine Neoplasms / virology
  • Viral Proteins / analysis

Substances

  • Antibodies, Monoclonal
  • Antibodies, Viral
  • Immunoglobulin M
  • Viral Proteins
  • RNA-Directed DNA Polymerase