Antigenic cross-reactivity between Schistosoma mansoni and peanut: a role for cross-reactive carbohydrate determinants (CCDs) and implications for the hygiene hypothesis.
Immunology
; 150(4): 506-517, 2017 04.
Article
em En
| MEDLINE
| ID: mdl-28201853
ABSTRACT
The antigenic reactivity of constituents of Schistosoma mansoni and peanut (Arachis hypogaea) was investigated to determine whether identical antigenic epitopes possessed by both organisms provided a possible explanation for the negative correlation between chronic schistosome infection and atopy to allergens. Aqueous extracts of peanuts were probed in Western immunoblots with rabbit IgG antibodies raised against the egg, cercarial and adult worm stages of S. mansoni. Several molecules in the peanut extract were antigenically reactive with antibodies from the various rabbit anti-schistosome sera. A pair of cross-reactive peanut molecules at ~30 000-33 000 molecular weight was purified and both proteins were identified by mass spectrometric analysis as the peanut allergen Ara h 1. Anti-S. mansoni soluble egg antigen antibodies that were eluted off the peanut molecules reacted with two S. mansoni egg antigens identified by mass spectrometry as IPSE/α-1 and κ-5. Alignments of the amino acid sequences of Ara h 1 and either IPSE/α-1 or κ-5 revealed a low level of peptide sequence identity. Incubation of nitrocellulose paper carrying electrophoresed peanut molecules, six constituents of other allergic plants and S. mansoni egg antigens in a mild solution of sodium metaperiodate before probing with antibodies, inhibited most of the cross-reactivities. The results are consistent with the antigenic cross-reactive epitopes of S. mansoni egg antigens, peanut and other allergic plants being cross-reactive carbohydrate determinants (CCDs). These findings are novel and an explanation based on 'blocking antibodies' could provide an insight for the inverse relationship observed between schistosome infection and allergies.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Schistosoma mansoni
/
Esquistossomose
/
Células Th2
/
Células Th1
/
Reações Cruzadas
/
Hipersensibilidade a Amendoim
Tipo de estudo:
Prognostic_studies
Limite:
Animals
/
Humans
Idioma:
En
Revista:
Immunology
Ano de publicação:
2017
Tipo de documento:
Article