title: Cytokine response profiles predict species-specific infection patterns in human GI nematodes.
abstract: This study investigated associations between pre-treatment cytokine expression and infection patterns, before and after de-worming, in humans exposed to two gastrointestinal nematode species. Quantitative measures of Ascaris lumbricoides and Trichuris trichiura infection (based on faecal egg counts) were estimated immediately before and 8-9 months after treatment in a Cameroonian population. Whole blood cytokine responses to parasite-derived antigens were assayed immediately pre-treatment. An overall measure of the tendency towards species-specific infection (increasing with A. lumbricoides faecal egg counts and decreasing with T. trichiura faecal egg counts) was significantly positively related to IL-10 levels in older (14-57 year) hosts. There was a significant negative influence of IL-5 on reinfection probability in T. trichiura but not A. lumbricoides. This effect coincided with reduced reinfection success in T. trichiura compared to A. lumbricoides. T(H)2 cytokine expression by younger hosts (4-13 year) was negatively associated with contemporary A. lumbricoides faecal egg counts before treatment. Following treatment, the pre-treatment T(H)2 cytokine expression data for younger hosts (now reflecting responsiveness 8-9 months in the past) were negatively associated with T. trichiura faecal egg counts. Taken together, these observations suggest a successional interaction between T(H)2-driven immune responses and species infection over time. However, any differential effects of the measured immune responses on species-specific recruitment, maturation and mortality were superimposed upon (and outweighed by) the effects of other factors favouring coinfection.
authors.affiliation: School of Biology, Nottingham University, Nottingham NG7 2RD, UK.
authors.forename: J A
authors.initials: JA
authors.lastname: Jackson
authors.forename: J D
authors.initials: JD
authors.lastname: Turner
authors.forename: L
authors.initials: L
authors.lastname: Rentoul
authors.forename: H
authors.initials: H
authors.lastname: Faulkner
authors.forename: J M
authors.initials: JM
authors.lastname: Behnke
authors.forename: M
authors.initials: M
authors.lastname: Hoyle
authors.forename: R K
authors.initials: RK
authors.lastname: Grencis
authors.forename: K J
authors.initials: KJ
authors.lastname: Else
authors.forename: J
authors.initials: J
authors.lastname: Kamgno
authors.forename: J E
authors.initials: JE
authors.lastname: Bradley
authors.forename: M
authors.initials: M
authors.lastname: Boussinesq
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D001196:Ascariasis / Q000097:blood / Q000276:immunology; D017164:Ascaris lumbricoides / Q000472:pathogenicity; D002648:Child; D002675:Child, Preschool; D016207:Cytokines / Q000097:blood*; D005260:Female; D005767:Gastrointestinal Diseases / Q000097:blood* / Q000276:immunology; D006801:Humans; D016753:Interleukin-10 / Q000097:blood; D018793:Interleukin-13 / Q000097:blood; D015848:Interleukin-5 / Q000097:blood; D007411:Intestinal Diseases, Parasitic / Q000097:blood / Q000276:immunology; D008297:Male; D008875:Middle Aged; D009349:Nematode Infections / Q000097:blood* / Q000276:immunology; D010270:Parasite Egg Count; D013045:Species Specificity; D014257:Trichuriasis / Q000097:blood / Q000276:immunology; D014258:Trichuris / Q000472:pathogenicity
chemical_list: D016207:Cytokines; D018793:Interleukin-13; D015848:Interleukin-5; D016753:Interleukin-10