Early expression of iepsilon, CD23 (FcepsilonRII), IL-4Ralpha, and IgE in the human fetus.

Academic Article

Abstract

  • BACKGROUND: A major predictor of childhood atopy is the concentration of IgE in the cord blood, but whether the source of cord blood IgE is maternal or fetal remains unclear. OBJECTIVE: We sought to determine the pattern of in situ IgE production during ontogeny. METHODS: Ninety-seven fetal, 142 natal, and 96 childhood samples were analyzed by using reverse transcription PCR for transcription of VDJCepsilon, Iepsilon, and CD23. Thirty-eight fetal liver samples were analyzed for the IL4RA genotype. RESULTS: IL-4Ralpha, CD23a, CD23b, and sterile Iepsilon transcripts were present as early as 8 weeks' gestation. VDJCepsilon transcripts were found in second-trimester fetal liver and third-trimester cord blood, although they were rare. VDJCepsilon transcripts were more common in the blood of children 9 months and older. Sequence analysis suggested that fetal VDJCepsilon was the product of selection. All fetal livers actively transcribing Iepsilon, VDJCepsilon, and IL-4Ralpha contained at least one copy of the atopy-associated IL4RA*A1902G polymorphism. CONCLUSION: The human fetus contains B cells that are primed to undergo IgE class switching from the earliest stages of ontogeny and can produce endogenous IgE by 20 weeks' gestation. However, IgE-producing cells are rare until 9 months after birth.
  • Keywords

  • Adult, Alleles, Cell Line, Fetal Blood, Fetus, Gene Expression, Gestational Age, Humans, Immunoglobulin Constant Regions, Immunoglobulin E, Immunoglobulin Joining Region, Immunoglobulin Variable Region, Immunoglobulin epsilon-Chains, Immunoglobulin mu-Chains, Infant, Liver, Receptors, IgE, Receptors, Interleukin-4, Time Factors
  • Pubmed Id

  • 25029509
  • Author List

  • Lima JO; Zhang L; Atkinson TP; Philips J; Dasanayake AP; Schroeder HW
  • Start Page

  • 911
  • End Page

  • 917
  • Volume

  • 106
  • Issue

  • 5