Enhanced diagnostic specificity in human filariasis by IgG4 antibody assessment

J Infect Dis. 1988 Nov;158(5):1034-7. doi: 10.1093/infdis/158.5.1034.

Abstract

Phosphocholine (PC), an immunodominant molecule present on a wide range of organisms, including filariae, evokes antibody responses that lead to false-positive reactions in routine serological assays. Humans essentially do not respond to PC in the IgG4 subclass; therefore, by configuring an enzyme immunoassay to assess antibodies of the IgG4 subclass only, we were able to eliminate serological false-positive results in 32 of 34 cross-reactive sera from patients with non-filarial parasitic infections. Specificity was thus greatly enhanced with minimal loss of sensitivity. Because preadsorption of these cross-reactive sera to remove antibodies to PC eliminated only approximately 50% of the original cross-reactivity, other shared epitopes (perhaps similar to PC) are also likely to be restricted by IgG subclass.

MeSH terms

  • Animals
  • Antibodies, Helminth / analysis*
  • Antibodies, Helminth / biosynthesis
  • Antibodies, Helminth / immunology
  • Antigens, Helminth / immunology
  • Cross Reactions
  • Enzyme-Linked Immunosorbent Assay
  • Epitopes / immunology
  • False Positive Reactions
  • Filariasis / diagnosis*
  • Filarioidea / immunology*
  • Humans
  • Immunoglobulin G / analysis*
  • Immunoglobulin G / biosynthesis
  • Immunoglobulin G / immunology
  • Phosphorylcholine / immunology
  • Predictive Value of Tests

Substances

  • Antibodies, Helminth
  • Antigens, Helminth
  • Epitopes
  • Immunoglobulin G
  • Phosphorylcholine