Human IgE does not bind to human FcRn

Sci Rep. 2022 Jan 7;12(1):62. doi: 10.1038/s41598-021-03852-1.

Abstract

The neonatal Fc receptor (FcRn) is known to mediate placental transfer of IgG from mother to unborn. IgE is widely known for triggering immune responses to environmental antigens. Recent evidence suggests FcRn-mediated transplacental passage of IgE during pregnancy. However, direct interaction of FcRn and IgE was not investigated. Here, we compared binding of human IgE and IgG variants to recombinant soluble human FcRn with β2-microglobulin (sFcRn) in surface plasmon resonance (SPR) at pH 7.4 and pH 6.0. No interaction was found between human IgE and human sFcRn. These results imply that FcRn can only transport IgE indirectly, and thereby possibly transfer allergenic sensitivity from mother to fetus.

Publication types

  • Comparative Study

MeSH terms

  • Biological Transport
  • Female
  • Histocompatibility Antigens Class I / metabolism*
  • Humans
  • Hydrogen-Ion Concentration
  • Immunoglobulin E / metabolism*
  • Immunoglobulin G / metabolism
  • Maternal-Fetal Exchange
  • Placenta / metabolism*
  • Pregnancy
  • Protein Binding
  • Receptors, Fc / metabolism*
  • Surface Plasmon Resonance
  • beta 2-Microglobulin / metabolism

Substances

  • B2M protein, human
  • Histocompatibility Antigens Class I
  • Immunoglobulin G
  • Receptors, Fc
  • beta 2-Microglobulin
  • Immunoglobulin E
  • Fc receptor, neonatal