Parasite-specific antibody and cellular immune responses in human infected with Necator americanus and Oesophagostomum bifurcum

Parasitol Res. 2001 Sep;87(9):722-9. doi: 10.1007/s004360100419.


In this study parasite-specific antibody, cellular reactivity and Thl-type or Th2-type cytokine responses were investigated in humans concurrently infected with Necator americanus and Oesophagostomum bifurcum. The prospects for O. bifurcum-specific serodiagnosis based on IgG4 and IgE were evaluated. IgG4 showed low specificity for O. bifurcum due to antigen cross-reactivity with N. americanus, while IgE specifically distinguished between hookworm and O. bifurcum, and, in doubly infected patients, levels of O. bifurcum-specific as well as N. americanus-specific IgE were significantly elevated compared to those with N. americanus mono-infections. Cellular immunity was not strictly dominated by a Thl- or Th2- type reactivity. In co-infected patients cellular unresponsiveness to parasite antigens was observed, while cellular production of tumour necrosis factor alpha (TNF-alpha) and gamma-interferon (IFN-gamma) was greater in those doubly infected. Th2-type cytokines (interleukin-5 and interleukin-10) were produced in equal amounts by peripheral blood mononuclear cells from individuals with mono- and coinfections. Such mixed Thl-type and Th2-type immune responsiveness associated with persisting gastrointestinal parasitic nematodes may reflect a state of infection at which parasite-induced inflammatory and enteropathogenic responses co-exist, and furthermore, helminth coinfection will not only suppress parasite-specific cellular responsiveness but may also direct cytokine production towards a "permissive Th1-type cytokine profile" that favours parasite persistence.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Animals
  • Antibodies, Helminth / blood
  • Antibodies, Helminth / immunology*
  • Antibody Specificity*
  • Antigens, Helminth / immunology
  • Child
  • Cytokines / metabolism
  • Female
  • Humans
  • Immunity, Cellular
  • Immunoglobulin E / blood
  • Immunoglobulin G / blood
  • Male
  • Middle Aged
  • Necator americanus / immunology*
  • Necatoriasis / complications
  • Necatoriasis / immunology*
  • Necatoriasis / parasitology
  • Oesophagostomiasis / complications
  • Oesophagostomiasis / immunology*
  • Oesophagostomiasis / parasitology
  • Oesophagostomum / immunology*
  • T-Lymphocytes / immunology
  • T-Lymphocytes / metabolism


  • Antibodies, Helminth
  • Antigens, Helminth
  • Cytokines
  • Immunoglobulin G
  • Immunoglobulin E