T-helper 17 cells are associated with pathology in human schistosomiasis

J Infect Dis. 2013 Jan 1;207(1):186-95. doi: 10.1093/infdis/jis654. Epub 2012 Oct 19.


Background: Schistosome infections are often clinically silent, but some individuals develop severe pathological reactions. In several disease processes, T-helper 17 (Th17) cells have been linked to tissue injuries, while regulatory T cells (Tregs) are thought to downmodulate inflammatory reactions. We assessed whether bladder pathology in human Schistosoma haematobium infection is related to the balance of Th17 cells and Tregs. We used a murine model of Schistosoma mansoni infection to further investigate whether the peripheral profiles reflected ongoing events in tissues.

Methods: We characterized T-helper cell subsets in the peripheral blood of children residing in a S. haematobium-endemic area and in the peripheral blood, spleen, and hepatic granulomas of S. mansoni-infected high-pathology CBA mice and low-pathology C57BL/6 mice.

Results: S. haematobium-infected children with bladder pathology had a significantly higher percentage of Th17 cells than those without pathology. Moreover, the Th17/Treg ratios were significantly higher in infected children with pathology, compared with infected children without pathology. Percentages of interleukin 17-producing cells were significantly higher in spleen and granulomas of CBA mice, compared with C57BL/6 mice. This difference was also reflected in the peripheral blood.

Conclusions: This is the first study to indicate that Th17 cells may be involved in the pathogenesis of human schistosomiasis.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Animals
  • Child
  • Child, Preschool
  • Cytokines / immunology
  • Female
  • Granulocytes / pathology
  • Host-Parasite Interactions / immunology
  • Humans
  • Interleukin-17 / immunology
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Inbred CBA
  • Middle Aged
  • Schistosoma haematobium / immunology*
  • Schistosoma mansoni / immunology
  • Schistosomiasis haematobia / parasitology
  • Schistosomiasis haematobia / pathology*
  • Schistosomiasis mansoni / parasitology
  • Schistosomiasis mansoni / pathology
  • Spleen / parasitology
  • Spleen / pathology
  • T-Lymphocytes, Regulatory / immunology*
  • Th17 Cells / immunology*
  • Urinary Bladder / parasitology
  • Urinary Bladder / pathology
  • Young Adult


  • Cytokines
  • Interleukin-17