title: The effect of different adjuvants on immune parameters and protection following vaccination of sheep with a larval-specific antigen of the gastrointestinal nematode, Haemonchus contortus.
abstract: It has recently been recognised that vaccine adjuvants play a critical role in directing the nature of a vaccine induced effector response. In the present study, several adjuvants were evaluated for their ability to protect sheep after field vaccination with the larval-specific Haemonchus contortus antigen, HcsL3. Using a suboptimal antigen dose, aluminium adjuvant was shown to reduce the cumulative faecal egg counts (cFEC) and worm burden by 23% and 25% respectively, in agreement with a previous study. The addition of Quil A to the aluminium-adjuvanted vaccine brought cFEC back to control levels. Vaccination with the adjuvant DEAE-dextran almost doubled the protection compared to the aluminium-adjuvanted vaccine resulting in 40% and 41% reduction in cFEC and worm counts compared to controls. Examination of skin responses following i.d. injection of exsheathed L3, revealed that cFEC was negatively correlated with wheal size and tissue eosinophils for the DEAE-dextran and aluminium-adjuvanted groups respectively. These studies have for the first time shown the potential of DEAE-dextran adjuvant for helminth vaccines, and discovered significant cellular correlates of vaccine-induced protection.
authors.affiliation: School of Biomedical Sciences, Monash University, Clayton, Victoria, Australia ; The ARC Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Clayton, Victoria, Australia.
authors.forename: David
authors.initials: D
authors.lastname: Piedrafita
authors.forename: Sarah
authors.initials: S
authors.lastname: Preston
authors.forename: Joanna
authors.initials: J
authors.lastname: Kemp
authors.forename: Michael
authors.initials: M
authors.lastname: de Veer
authors.forename: Jayne
authors.initials: J
authors.lastname: Sherrard
authors.forename: Troy
authors.initials: T
authors.lastname: Kraska
authors.forename: Martin
authors.initials: M
authors.lastname: Elhay
authors.forename: Els
authors.initials: E
authors.lastname: Meeusen
mesh_terms: D000276:Adjuvants, Immunologic / Q000494:pharmacology; D000277:Adjuvants, Pharmaceutic / Q000494:pharmacology*; D000818:Animals; D000909:Antibodies, Helminth / Q000276:immunology; D000947:Antigens, Helminth / Q000276:immunology*; D003637:DEAE-Dextran / Q000494:pharmacology; D005243:Feces / Q000469:parasitology; D005767:Gastrointestinal Diseases / Q000188:drug therapy / Q000276:immunology* / Q000469:parasitology; D006188:Haemonchiasis / Q000178:diet therapy / Q000276:immunology / Q000469:parasitology; D006189:Haemonchus / Q000187:drug effects / Q000276:immunology*; D007814:Larva / Q000187:drug effects / Q000276:immunology*; D009348:Nematoda / Q000187:drug effects / Q000276:immunology*; D009349:Nematode Infections / Q000188:drug therapy / Q000276:immunology / Q000469:parasitology; D010270:Parasite Egg Count / Q000379:methods; D012756:Sheep / Q000276:immunology* / Q000469:parasitology; D012757:Sheep Diseases / Q000188:drug therapy / Q000276:immunology / Q000469:parasitology; D014611:Vaccination / Q000379:methods; D014612:Vaccines / Q000276:immunology
chemical_list: D000276:Adjuvants, Immunologic; D000277:Adjuvants, Pharmaceutic; D000909:Antibodies, Helminth; D000947:Antigens, Helminth; D014612:Vaccines; D003637:DEAE-Dextran