title: Peanut-specific IgE antibodies in asymptomatic Ghanaian children possibly caused by carbohydrate determinant cross-reactivity.
abstract: BACKGROUND
  The prevalence of peanut allergy has increased in developed countries, but little is known about developing countries with high peanut consumption and widespread parasitic infections.
  
  
  OBJECTIVE
  We sought to investigate peanut allergy in Ghana.
  
  
  METHODS
  In a cross-sectional survey among Ghanaian schoolchildren (n = 1604), data were collected on reported adverse reactions to peanut, peanut sensitization (serum specific IgE and skin reactivity), consumption patterns, and parasitic infections. In a subset (n = 43) IgE against Ara h 1, 2, 3, and 9 as well as cross-reactive carbohydrate determinants (CCDs) was measured by using ImmunoCAP. Cross-reactivity and biological activity were investigated by means of ImmunoCAP inhibition and basophil histamine release, respectively.
  
  
  RESULTS
  Adverse reactions to peanut were reported in 1.5%, skin prick test reactivity in 2.0%, and IgE sensitization (≥0.35 kU/L) in 17.5% of participants. Moreover, 92.4% of those IgE sensitized to peanut (≥0.35 kU/L) had negative peanut skin prick test responses. Schistosoma haematobium infection was positively associated with IgE sensitization (adjusted odds ratio, 2.29; 95% CI, 1.37-3.86). In the subset IgE titers to Ara h 1, 2, 3, and 9 were low (<1.3 kU/L), except for 6 moderately strong reactions to Ara h 9. IgE against peanut was strongly correlated with IgE against CCDs (r = 0.89, P < .0001) and could be almost completely inhibited by CCDs, as well as S haematobium soluble egg antigen. Moreover, IgE to peanut showed poor biological activity.
  
  
  CONCLUSIONS
  Parasite-induced IgE against CCDs might account largely for high IgE levels to peanut in our study population of Ghanaian schoolchildren. No evidence of IgE-mediated peanut allergy was found.
authors.affiliation: Department of Parasitology, Noguchi Memorial Institute for Medical Research, Accra, Ghana; Department of Parasitology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Abena S
authors.initials: AS
authors.lastname: Amoah
authors.affiliation: Department of Parasitology, Noguchi Memorial Institute for Medical Research, Accra, Ghana; Department of Parasitology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Benedicta B
authors.initials: BB
authors.lastname: Obeng
authors.affiliation: Department of Parasitology, Noguchi Memorial Institute for Medical Research, Accra, Ghana.
authors.forename: Irene A
authors.initials: IA
authors.lastname: Larbi
authors.affiliation: Department of Experimental Immunology and Department of Otorhinolaryngology, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Serge A
authors.initials: SA
authors.lastname: Versteeg
authors.affiliation: Department of Parasitology, Noguchi Memorial Institute for Medical Research, Accra, Ghana.
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Aryeetey
authors.affiliation: Department of Experimental Immunology and Department of Otorhinolaryngology, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Jaap H
authors.initials: JH
authors.lastname: Akkerdaas
authors.affiliation: Department of Experimental Immunology and Department of Otorhinolaryngology, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Laurian
authors.initials: L
authors.lastname: Zuidmeer
authors.affiliation: Thermo Fisher Scientific, Uppsala, Sweden.
authors.forename: Jonas
authors.initials: J
authors.lastname: Lidholm
authors.affiliation: Servicio de Alergia, Hospital Clinico San Carlos, Madrid, Spain.
authors.forename: Montserrat
authors.initials: M
authors.lastname: Fernández-Rivas
authors.affiliation: Department of Parasitology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Franca C
authors.initials: FC
authors.lastname: Hartgers
authors.affiliation: Department of Parasitology, Noguchi Memorial Institute for Medical Research, Accra, Ghana.
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Boakye
authors.affiliation: Department of Experimental Immunology and Department of Otorhinolaryngology, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Ronald
authors.initials: R
authors.lastname: van Ree
authors.affiliation: Department of Parasitology, Leiden University Medical Center, Leiden, The Netherlands. Electronic address: M.Yazdanbakhsh@lumc.nl.
authors.forename: Maria
authors.initials: M
authors.lastname: Yazdanbakhsh
mesh_terms: D000485:Allergens / Q000276:immunology; D052179:Antigens, Plant / Q000276:immunology; D010367:Arachis / Q000276:immunology*; D001491:Basophils / Q000276:immunology; D002241:Carbohydrates / Q000276:immunology*; D002648:Child; D003429:Cross Reactions; D005260:Female; D005869:Ghana / Q000453:epidemiology; D006636:Histamine Release; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood*; D008297:Male; D021183:Peanut Hypersensitivity / Q000453:epidemiology / Q000276:immunology*; D012553:Schistosomiasis haematobia / Q000453:epidemiology / Q000276:immunology*; D012882:Skin Tests
chemical_list: D000485:Allergens; D052179:Antigens, Plant; D002241:Carbohydrates; D007073:Immunoglobulin E
keywords: Adjusted odds ratio; BHR; Basophil histamine release; CCD; CRD; Component-resolved diagnostics; Cross-reactive carbohydrate determinant; EuroPrevall; IgE; IgE cross-reactivity; Peanut allergy; SEA; SPT; Skin prick test; Soluble egg antigen; Sub-Saharan Africa; aOR; basophil histamine release; cross-reactive carbohydrate determinants; helminth infections; skin prick testing