title: Development of antibody isotype responses to Schistosoma mansoni in an immunologically naive immigrant population: influence of infection duration, infection intensity, and host age.
abstract: We have identified the influence of host and parasite factors that give rise to characteristic antibody isotype profiles with age seen in human populations living in different areas of schistosomiasis endemicity. This is important in the immunobiology of this disease. It is also of interest in the context of human responses to chronic antigen stimulation, vaccines, allergens, and other pathogens. In populations exposed to endemic schistosomiasis, factors such as intensity and duration of infection are age dependent. They therefore confound the influence of host age on antiparasite responses. Here, we resolved these confounding factors by comparing the developing antibody responses of an immunologically naive immigrant population as they acquired the infection for the first time with those of chronically infected resident inhabitants of the same region of Schistosoma mansoni endemicity in Kenya. Recent arrival in the area strongly favored immunoglobulin G3 (IgG3) responses against the parasite. The antibody isotype responses associated with human susceptibility to reinfection after chemotherapy were elevated in those suffering high intensities of infection (IgG4 responses against worm and egg antigens) or were characteristic responses of young children irrespective of the intensity or duration of infection (IgG2 responses against egg antigen). IgE responses against the adult worm, a response associated with resistance to reinfection after chemotherapy, increased with the ages of infected individuals and were also favored in those currently suffering higher intensities of infection.
authors.affiliation: Division of Microbiology and Parasitology, Department of Pathology, University of Cambridge, Cambridge, United Kingdom.
authors.forename: C W
authors.initials: CW
authors.lastname: Naus
authors.forename: G
authors.initials: G
authors.lastname: Kimani
authors.forename: J H
authors.initials: JH
authors.lastname: Ouma
authors.forename: A J
authors.initials: AJ
authors.lastname: Fulford
authors.forename: M
authors.initials: M
authors.lastname: Webster
authors.forename: G J
authors.initials: GJ
authors.lastname: van Dam
authors.forename: A M
authors.initials: AM
authors.lastname: Deelder
authors.forename: A E
authors.initials: AE
authors.lastname: Butterworth
authors.forename: D W
authors.initials: DW
authors.lastname: Dunne
mesh_terms: D000328:Adult; D000367:Age Factors; D000818:Animals; D000909:Antibodies, Helminth / Q000276:immunology*; D000918:Antibody Specificity; D000947:Antigens, Helminth / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D004641:Emigration and Immigration; D005260:Female; D006801:Humans; D007132:Immunoglobulin Isotypes / Q000276:immunology; D007630:Kenya / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012550:Schistosoma mansoni / Q000276:immunology*; D012555:Schistosomiasis mansoni / Q000453:epidemiology / Q000276:immunology* / Q000503:physiopathology
chemical_list: D000909:Antibodies, Helminth; D000947:Antigens, Helminth; D007132:Immunoglobulin Isotypes