Expression of retrovirus-related antigen in pregnancy. II. Cytotoxic and blocking specificities of immunoglobulins eluted from the placenta

J Reprod Immunol. 1981 Mar;2(6):323-30. doi: 10.1016/0165-0378(81)90002-4.

Abstract

Immunoglobulins, mostly of the IgG class, were detected in eluates of the placenta of 75% of 50 healthy women in their first or second pregnancy, 92% of 30 women with more than two pregnancies, and 87% of 23 pre-eclamptic patients. The immunoglobulins were assayed for complement-dependent cytotoxicity on human and monkey cell-lines, as well as on the same cells chronically infected with either Mason-Pfizer Virus (M-P V) or Baboon Endogenous Virus (BeV). The frequency of cytotoxic reactions was very low, except with immunoglobulins from the pre-eclamptic placentae, where one third of the samples lysed virus-infected cells with occasional killing of virus-free cells. All placental immunoglobulins which were not cytotoxic were then assayed for blocking activity by testing whether they could compete with the action of anticellular sera of virus-free cells, or with the toxic effect of antiviral sera on virus producing cells. 64% of the immunoglobulins from normal placentae competed with antiviral antibodies while only 17% blocked the action of anticellular sera. The frequency of blocking immunoglobulins was no greater in eluates from pre-eclamptic placentae. The data indicate that the placenta possesses retrovirus antigen sites which bind blocking antibodies in normal pregnancy and complement-dependent cytotoxic antibodies in pre-eclampsia.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibody Specificity
  • Antigens, Viral*
  • Binding, Competitive
  • Cytotoxicity, Immunologic*
  • Female
  • Haplorhini
  • HeLa Cells / immunology
  • Humans
  • Immune Sera / pharmacology
  • Immunoglobulin A
  • Immunoglobulin G
  • Immunoglobulins
  • Papio
  • Placenta / immunology*
  • Pre-Eclampsia / immunology
  • Pregnancy
  • Rabbits
  • Retroviridae / immunology*

Substances

  • Antigens, Viral
  • Immune Sera
  • Immunoglobulin A
  • Immunoglobulin G
  • Immunoglobulins