Cellular responses and cytokine production in post-treatment hookworm patients from an endemic area in Brazil

Clin Exp Immunol. 2004 May;136(2):334-40. doi: 10.1111/j.1365-2249.2004.02449.x.


Human hookworm infections are distributed widely in tropical areas and have a significant impact on host morbidity and human health. In the present study, we investigated the cellular responsiveness and cytokine production in peripheral blood mononuclear cells (PBMC) from Necator americanus-infected schoolchildren who had recently received chemotherapy, and compared them with non-infected endemic controls. Hookworm patients and treated, egg-negative individuals showed a lower cellular reactivity against phytohaemagglutinin (PHA) and hookworm antigen when compared with egg-negative endemic controls. The baseline production of proinflammatory tumour necrosis factor-alpha (TNF-alpha) in PBMC from infected patients and treated, egg-negative individuals was elevated. On the other hand, PHA- or hookworm antigen-induced interleukin (IL)-12 and interferon (IFN)-gamma secretion was higher in endemic controls than in hookworm patients, who either continued egg-positive or were egg-negative after treatment. Also, PBMC from endemic controls secreted more IL-5 and IL-13 than the other patient groups. Opposite to that, the spontaneous as well as the antigen-driven IL-10 secretion was lower in endemic controls when compared with the other groups. In summary, patently hookworm-infected as well as egg-negative treated patients disclosed an elevated spontaneous cellular secretion of proinflammatory TNF-alpha, a prominent secretion of regulatory Th2-type IL-10 and an impaired production of IL-12, IFN-gamma, IL-5 and IL-13.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Albendazole / therapeutic use
  • Animals
  • Anthelmintics / therapeutic use
  • Antibodies, Helminth / blood*
  • Brazil
  • Case-Control Studies
  • Child
  • Cytokines / metabolism*
  • Disease Outbreaks
  • Humans
  • Interferon-gamma / metabolism
  • Interleukin-12 / metabolism
  • Interleukin-13 / metabolism
  • Interleukin-5 / metabolism
  • Leukocytes, Mononuclear / metabolism*
  • Morbidity
  • Necator americanus*
  • Necatoriasis / drug therapy
  • Necatoriasis / immunology*
  • Parasite Egg Count
  • Statistics, Nonparametric
  • Tumor Necrosis Factor-alpha / immunology


  • Anthelmintics
  • Antibodies, Helminth
  • Cytokines
  • Interleukin-13
  • Interleukin-5
  • Tumor Necrosis Factor-alpha
  • Interleukin-12
  • Interferon-gamma
  • Albendazole