title: Enhanced pro-inflammatory cytokine responses following Toll-like-receptor ligation in Schistosoma haematobium-infected schoolchildren from rural Gabon.
abstract: BACKGROUND
  Schistosoma infection is thought to lead to down-regulation of the host's immune response. This has been shown for adaptive immune responses, but the effect on innate immunity, that initiates and shapes the adaptive response, has not been extensively studied. In a first study to characterize these responses, we investigated the effect of Schistosoma haematobium infection on cytokine responses of Gabonese schoolchildren to a number of Toll-like receptor (TLR) ligands.
  
  
  METHODS
  Peripheral blood mononuclear cells (PBMCs) were collected from S. haematobium-infected and uninfected schoolchildren from the rural area of Zilé in Gabon. PBMCs were incubated for 24 h and 72 h with various TLR ligands, as well as schistosomal egg antigen (SEA) and adult worm antigen (AWA). Pro-inflammatory TNF-α and anti-inflammatory/regulatory IL-10 cytokine concentrations were determined in culture supernatants.
  
  
  RESULTS
  Infected children produced higher adaptive IL-10 responses than uninfected children against schistosomal antigens (72 h incubation). On the other hand, infected children had higher TNF-α responses than uninfected children and significantly higher TNF-α to IL-10 ratios in response to FSL-1 and Pam3, ligands of TLR2/6 and TLR2/1 respectively. A similar trend was observed for the TLR4 ligand LPS while Poly(I:C) (Mda5/TLR3 ligand) did not induce substantial cytokine responses (24 h incubation).
  
  
  CONCLUSIONS
  This pilot study shows that Schistosoma-infected children develop a more pro-inflammatory TLR2-mediated response in the face of a more anti-inflammatory adaptive immune response. This suggests that S. haematobium infection does not suppress the host's innate immune system in the context of single TLR ligation.
authors.affiliation: Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium. lemurs@itg.be
authors.forename: Lynn
authors.initials: L
authors.lastname: Meurs
authors.forename: Lucja
authors.initials: L
authors.lastname: Labuda
authors.forename: Abena Serwaa
authors.initials: AS
authors.lastname: Amoah
authors.forename: Moustapha
authors.initials: M
authors.lastname: Mbow
authors.forename: Ulysse Ateba
authors.initials: UA
authors.lastname: Ngoa
authors.forename: Daniel Adjei
authors.initials: DA
authors.lastname: Boakye
authors.forename: Souleymane
authors.initials: S
authors.lastname: Mboup
authors.forename: Tandakha Ndiaye
authors.initials: TN
authors.lastname: Dièye
authors.forename: Adrian P
authors.initials: AP
authors.lastname: Mountford
authors.forename: Joseph D
authors.initials: JD
authors.lastname: Turner
authors.forename: Peter Gottfried
authors.initials: PG
authors.lastname: Kremsner
authors.forename: Katja
authors.initials: K
authors.lastname: Polman
authors.forename: Maria
authors.initials: M
authors.lastname: Yazdanbakhsh
authors.forename: Ayola Akim
authors.initials: AA
authors.lastname: Adegnika
mesh_terms: D000293:Adolescent; D000818:Animals; D002478:Cells, Cultured; D002648:Child; D016207:Cytokines / Q000096:biosynthesis / Q000097:blood / Q000276:immunology*; D005260:Female; D006801:Humans; D018836:Inflammation Mediators / Q000276:immunology*; D007963:Leukocytes, Mononuclear / Q000378:metabolism / Q000469:parasitology; D008024:Ligands; D008297:Male; D012424:Rural Population; D012548:Schistosoma haematobium / Q000276:immunology*; D012553:Schistosomiasis haematobia / Q000276:immunology / Q000469:parasitology*; D012574:Schools; D051193:Toll-Like Receptors / Q000276:immunology*
chemical_list: D016207:Cytokines; D018836:Inflammation Mediators; D008024:Ligands; D051193:Toll-Like Receptors