Article

Protection studies with integral membrane fractions of Haemonchus contortus.

Moredun Research Institute, Edinburgh, Scotland, UK.
Parasite Immunology (impact factor: 2.6). 06/1994; 16(5):231-41. pp.231-41
Source: PubMed

ABSTRACT Techniques for targetting glycoproteins integral to the luminal membrane of the intestinal cells of Haemonchus contortus were used to isolate fractions of whole parasites with protective antigen potential. Sheep immunization trials with various candidate fractions revealed one which selectively bound to lectins with specificity for N-acetylgalactosamine and which reduced mean challenge worm burdens by up to 72% and mean faecal egg counts by up to 93%. The luminal surface of the intestines of the Haemonchus recovered from sheep immunized with this antigen were coated with host immunoglobulin, suggesting that the protective effect was due to antibodies interfering with the function of the gut. Further biochemical characterization of this fraction, which has been termed Haemonchus galactose-containing glycoprotein complex (H-gal-GP complex), showed that it could be distinguished from previously described protective antigens of this parasite and that it was only detectable in detergent extracts of the worms.

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Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

challenge worm burdens
 
fractions
 
Haemonchus galactose-containing glycoprotein complex
 
host immunoglobulin
 
intestinal cells
 
luminal surface
 
protective antigens
 
Sheep immunization trials
 
sheep immunized
 
specificity
 
targetting glycoproteins integral
 
Techniques
 
various candidate fractions
 
whole parasites
 
worms
 

W D Smith