title: Increases in levels of schistosome-specific immunoglobulin E and CD23(+) B cells in a cohort of Kenyan children undergoing repeated treatment and reinfection with Schistosoma mansoni.
abstract: BACKGROUND
  Age prevalence curves for areas in which schistosomiasis is endemic suggest that humans develop partial immunity to reinfection beginning in early adolescence. We conducted a 2-year longitudinal study to determine whether children infected with Schistosoma mansoni develop protection-related immune responses after treatment with praziquantel and whether the development of these immune responses is accelerated by frequent treatment after reinfection.
  
  
  METHODS
  Children (8-10 years old) were tested for S. mansoni every 4 months and treated with praziquantel when positive (arm A; n=68) or were tested and treated at the end of the 2-year follow-up period (arm B; n=49).
  
  
  RESULTS
  Children in arm A who remained free of infection during follow-up had significantly higher baseline levels of schistosome-specific immunoglobulin E (IgE) than did children with > or =2 repeat diagnoses of S. mansoni infection. Children with > or =2 repeat diagnoses of S. mansoni infection had significantly increased levels of anti-schistosome IgE and CD23(+) B cells after receiving > or =3 praziquantel treatments over the course of follow-up. No increase in either parameter was seen in children who received only the baseline praziquantel treatment.
  
  
  CONCLUSIONS
  B cell activation and anti-schistosome IgE are associated with resistance to S. mansoni in children, and these immunological parameters can be increased by multiple rounds of infections and praziquantel-induced cures.
authors.affiliation: Center for Tropical and Emerging Global Diseases and Department of Microbiology, University of Georgia, Athens, Georgia 30602-3799, USA.
authors.forename: Carla L
authors.initials: CL
authors.lastname: Black
authors.forename: Erick M O
authors.initials: EM
authors.lastname: Muok
authors.forename: Pauline N M
authors.initials: PN
authors.lastname: Mwinzi
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Carter
authors.forename: Diana M S
authors.initials: DM
authors.lastname: Karanja
authors.forename: W Evan
authors.initials: WE
authors.lastname: Secor
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Colley
mesh_terms: D000818:Animals; D000871:Anthelmintics / Q000627:therapeutic use; D000909:Antibodies, Helminth / Q000097:blood*; D001402:B-Lymphocytes / Q000737:chemistry / Q000276:immunology*; D002648:Child; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood*; D007630:Kenya; D008137:Longitudinal Studies; D008297:Male; D011223:Praziquantel / Q000627:therapeutic use; D017455:Receptors, IgE / Q000032:analysis*; D012008:Recurrence; D012550:Schistosoma mansoni / Q000276:immunology*; D012555:Schistosomiasis mansoni / Q000188:drug therapy / Q000276:immunology*
chemical_list: D000871:Anthelmintics; D000909:Antibodies, Helminth; D017455:Receptors, IgE; D007073:Immunoglobulin E; D011223:Praziquantel