title: Vaccination of lambs with the recombinant protein rHc23 elicits significant protection against Haemonchus contortus challenge.
abstract: Gene encoding a somatic protein of Haemonchus contortus (Hc23) known to confer significant protection against experimental haemonchosis has been cloned and expressed in a prokaryotic system. A cDNA library of H. contortus using the vector λ ZAP II was obtained. Full-length gene was amplified, cloned and expressed in Escherichia coli BL21. The recombinant protein was purified in Ni-NTA column. Recombinant protein (rHc23) had 203 aminoacids and a molecular mass of 24.15 kDa. Recombinant protein (100 μg/dose) with aluminum hydroxide as adjuvant was administered to 5-6 months age female Assaf lambs on days -42, -28 and -14. On day 0 animals were infected with 15,000 L3 of H. contortus. Vaccination with rHc23 elicited a significant protection against challenge, with >80% reductions in both fecal egg counts and average abomasal parasite burdens at the end of the experiment (45 days post challenge) besides lack of variations in packed cell volume. Results support the feasibility of vaccination against lamb haemonchosis with a recombinant product from an exposed antigen.
authors.affiliation: Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, 28040 Madrid, Spain.
authors.forename: Elshaima M
authors.initials: EM
authors.lastname: Fawzi
authors.affiliation: Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, 28040 Madrid, Spain.
authors.forename: María Elena
authors.initials: ME
authors.lastname: González-Sánchez
authors.affiliation: Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, 28040 Madrid, Spain.
authors.forename: María Jesús
authors.initials: MJ
authors.lastname: Corral
authors.affiliation: Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, 28040 Madrid, Spain. Electronic address: jmalunda@ucm.es.
authors.forename: José Ma
authors.initials: JM
authors.lastname: Alunda
authors.affiliation: Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, 28040 Madrid, Spain.
authors.forename: Montserrat
authors.initials: M
authors.lastname: Cuquerella
mesh_terms: D000018:Abomasum / Q000469:parasitology; D000276:Adjuvants, Immunologic; D000536:Aluminum Hydroxide; D000595:Amino Acid Sequence; D000818:Animals; D000947:Antigens, Helminth / Q000276:immunology*; D005243:Feces / Q000469:parasitology; D005260:Female; D015723:Gene Library; D006188:Haemonchiasis / Q000469:parasitology / Q000517:prevention & control / Q000662:veterinary*; D006189:Haemonchus / Q000276:immunology*; D008297:Male; D008969:Molecular Sequence Data; D010270:Parasite Egg Count / Q000662:veterinary; D011994:Recombinant Proteins; D012756:Sheep; D012757:Sheep Diseases / Q000469:parasitology / Q000517:prevention & control*; D014611:Vaccination / Q000662:veterinary*
chemical_list: D000276:Adjuvants, Immunologic; D000947:Antigens, Helminth; D011994:Recombinant Proteins; D000536:Aluminum Hydroxide
keywords: Cloning; DNA; Expression; Haemonchus contortus; Lambs; Recombinant antigen; Sheep; Vaccination; rHc23