title: Early interferon-gamma response against Plasmodium falciparum correlates with interethnic differences in susceptibility to parasitemia between sympatric Fulani and Dogon in Mali.
abstract: BACKGROUND
  Interethnic differences in susceptibility to malaria provide a unique opportunity to explore immunological correlates of protection. The Fulani of Sahelian Africa are known for their reduced susceptibility to Plasmodium falciparum, compared with surrounding tribes, yet the immunology underlying this is still poorly understood.
  
  
  RESULTS
  Here, we show that mononuclear cells from Fulani elicit >10-fold stronger interferon (IFN)-gamma production following a 24-h in vitro coincubation with asexual parasites than cells from sympatric Dogon. This response appears to be specific for P. falciparum among a panel of other human pathogens and is independent of the lower number of regulatory T cell counts present in Fulani. IFN-gamma responses in both tribes were inversely correlated with peripheral parasite density as quantified by nucleic acid sequenced-based amplification, but responses of Fulani remained significantly stronger than those of Dogon after adjustment for concurrent parasitemia, suggesting that hard-wired immunological differences underlie the observed protection.
  
  
  CONCLUSIONS
  These results underscore the value of early IFN-gamma responses to P. falciparum as a correlate of anti-parasite immunity, not only in this setting but also in the wider context of malaria, and support the development of malaria vaccines aimed at inducing such responses.
authors.affiliation: Department of Medical Microbiology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
authors.forename: Matthew B B
authors.initials: MB
authors.lastname: McCall
authors.forename: Joost
authors.initials: J
authors.lastname: Hopman
authors.forename: Modibo
authors.initials: M
authors.lastname: Daou
authors.forename: Boubacar
authors.initials: B
authors.lastname: Maiga
authors.forename: Victor
authors.initials: V
authors.lastname: Dara
authors.forename: Ivo
authors.initials: I
authors.lastname: Ploemen
authors.forename: Krystelle
authors.initials: K
authors.lastname: Nganou-Makamdop
authors.forename: Amadou
authors.initials: A
authors.lastname: Niangaly
authors.forename: Youssouf
authors.initials: Y
authors.lastname: Tolo
authors.forename: Charles
authors.initials: C
authors.lastname: Arama
authors.forename: J Teun
authors.initials: JT
authors.lastname: Bousema
authors.forename: Jos W
authors.initials: JW
authors.lastname: van der Meer
authors.forename: André J A M
authors.initials: AJ
authors.lastname: van der Ven
authors.forename: Marita
authors.initials: M
authors.lastname: Troye-Blomberg
authors.forename: Amagana
authors.initials: A
authors.lastname: Dolo
authors.forename: Ogobara K
authors.initials: OK
authors.lastname: Doumbo
authors.forename: Robert W
authors.initials: RW
authors.lastname: Sauerwein
mesh_terms: D000293:Adolescent; D000328:Adult; D002478:Cells, Cultured; D018920:Coculture Techniques; D004198:Disease Susceptibility / Q000208:ethnology* / Q000276:immunology; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism*; D007963:Leukocytes, Mononuclear / Q000378:metabolism* / Q000469:parasitology; D016778:Malaria, Falciparum / Q000208:ethnology* / Q000276:immunology*; D008297:Male; D008302:Mali; D018512:Parasitemia / Q000208:ethnology* / Q000276:immunology; D044382:Population Groups; D055815:Young Adult
chemical_list: D007371:Interferon-gamma