title: Changes in the levels of cytokines, chemokines and malaria-specific antibodies in response to Plasmodium falciparum infection in children living in sympatry in Mali.
abstract: BACKGROUND
  The Fulani are known to be less susceptible to Plasmodium falciparum malaria as reflected by lower parasitaemia and fewer clinical symptoms than other sympatric ethnic groups. So far most studies in these groups have been performed on adults, which is why little is known about these responses in children. This study was designed to provide more information on this gap.
  
  
  METHODS
  Circulating inflammatory factors and antibody levels in children from the Fulani and Dogon ethnic groups were measured. The inflammatory cytokines; interleukin (IL)-1beta, IL-6, IL-8, IL-10, IL-12p70, tumor necrosis factor (TNF) and the chemokines; regulated on activation normal T cell expressed and secreted (RANTES), monokine-induced by IFN-gamma (MIG), monocyte chemotactic protein (MCP)-1 and IFN-gamma-inducible protein (IP)-10 were measured by cytometric bead arrays. The levels of interferon (IFN)-alpha, IFN-gamma and malaria-specific antibodies; immunoglobulin (Ig) G, IgM and IgG subclasses (IgG1-IgG4) were measured by ELISA.
  
  
  RESULTS
  The results revealed that the Fulani children had higher levels of all tested cytokines compared to the Dogon, in particular IFN-gamma, a cytokine known to be involved in parasite clearance. Out of all the tested chemokines, only MCP-1 was increased in the Fulani compared to the Dogon. When dividing the children into infected and uninfected individuals, infected Dogon had significantly lower levels of RANTES compared to their uninfected peers, and significantly higher levels of MIG and IP-10 as well as MCP-1, although the latter did not reach statistical significance. In contrast, such patterns were not seen in the infected Fulani children and their chemokine levels remained unchanged upon infection compared to uninfected counterparts. Furthermore, the Fulani also had higher titres of malaria-specific IgG and IgM as well as IgG1-3 subclasses compared to the Dogon.
  
  
  CONCLUSIONS
  Taken together, this study demonstrates, in accordance with previous work, that Fulani children mount a stronger inflammatory and antibody response against P. falciparum parasites compared to the Dogon and that these differences are evident already at an early age. The inflammatory responses in the Fulani were not influenced by an active infection which could explain why less clinical symptoms are seen in this group.
authors.affiliation: Department of Immunology, Wenner-Gren Institute, Stockholm University, Svante Arrheniusväg 20C, 10691 Stockholm, Sweden. stephanie.bostrom@wgi.su.se
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Boström
authors.forename: Pablo
authors.initials: P
authors.lastname: Giusti
authors.forename: Charles
authors.initials: C
authors.lastname: Arama
authors.forename: Jan-Olov
authors.initials: JO
authors.lastname: Persson
authors.forename: Victor
authors.initials: V
authors.lastname: Dara
authors.forename: Boubacar
authors.initials: B
authors.lastname: Traore
authors.forename: Amagana
authors.initials: A
authors.lastname: Dolo
authors.forename: Ogobara
authors.initials: O
authors.lastname: Doumbo
authors.forename: Marita
authors.initials: M
authors.lastname: Troye-Blomberg
mesh_terms: D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood*; D002478:Cells, Cultured; D002648:Child; D002675:Child, Preschool; D016207:Cytokines / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005006:Ethnicity; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D016778:Malaria, Falciparum / Q000276:immunology*; D008297:Male; D008302:Mali; D010963:Plasmodium falciparum / Q000276:immunology*; D061350:Sympatry; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D000913:Antibodies, Protozoan; D016207:Cytokines; D007074:Immunoglobulin G; D007075:Immunoglobulin M