Identification and characterisation of an aspartyl protease inhibitor homologue as a major allergen of Trichostrongylus colubriformis.
Int J Parasitol
; 33(11): 1233-43, 2003 Sep 30.
Article
em En
| MEDLINE
| ID: mdl-13678638
ABSTRACT
Allergens were identified from the gastrointestinal nematode of sheep, Trichostrongylus colubriformis, by probing Western blots of infective larvae (third stage) somatic antigen with IgE purified from the serum of sheep grazed on worm contaminated pasture. A 31 kDa allergen was frequently recognised by sera from immune sheep, particularly those deriving from a line that has been genetically selected over 23 years for parasite resistance. Using a proteomic approach, the 31 kDa allergen was identified as an aspartyl protease inhibitor homologue. The entire coding sequence of T. colubriformis aspartyl protease inhibitor (Tco-api-1) was obtained and the mature protein expressed in Escherichia coli. Anti-Tco-API-1 antibodies revealed that a commonly observed 21 kDa T. colubriformis allergen species is a truncated form of Tco-API-1. Specific IgE responses to T. colubriformis aspartyl protease inhibitor were significantly correlated with the degree of resistance to nematode infection as measured by faecal egg count in sheep. Surprisingly, IgE responses to Tco-API-1 were not correlated with breech soiling (dag score), which is thought to be caused, in part, by allergic hypersensitivity to worms. Therefore, a specific IgE response to this allergen may be a suitable marker for identifying lambs at an early age that will develop strong immunity to gastrointestinal nematodes.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Doenças dos Ovinos
/
Tricostrongilose
/
Trichostrongylus
/
Alérgenos
/
Ácido Aspártico Endopeptidases
/
Antígenos de Helmintos
Tipo de estudo:
Diagnostic_studies
/
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Int J Parasitol
Ano de publicação:
2003
Tipo de documento:
Article
País de afiliação:
Nova Zelândia