title: Oral vaccination with microencapsuled strain 19 vaccine confers enhanced protection against Brucella abortus strain 2308 challenge in red deer (Cervus elaphus elaphus).
abstract: Bison (Bison bison) and elk (Cervus elaphus nelsoni) in the Greater Yellowstone Area (GYA), USA, are infected with Brucella abortus, the causative agent of bovine brucellosis, and they serve as a wildlife reservoir for the disease. Bovine brucellosis recently has been transmitted from infected elk to cattle in Montana, Wyoming, and Idaho and has resulted in their loss of brucellosis-free status. An efficacious Brucella vaccine with a delivery system suitable for wildlife would be a valuable tool in a disease prevention and control program. We evaluated Strain 19 (S19) in a sustained release vehicle consisting of alginate microspheres containing live vaccine. In a challenge study using red deer (Cervus elaphus elaphus) as a model for elk, alginate, a naturally occurring polymer combined with a protein of Fasciola hepatica vitelline protein B was used to microencapsulate S19. Red deer were orally or subcutaneously immunized with 1.5 x 10(10) colony-forming units (CFUs) using microencapsulated S19. Humoral and cellular profiles were analyzed bimonthly throughout the study. The vaccinated red deer and nonvaccinated controls were challenged 1 yr postimmunization conjunctivally with 1 x 10(9) CFUs of B. abortus strain 2308. Red deer vaccinated with oral microencapsulated S19 had a statistically significant lower bacterial tissue load compared with controls. These data indicate for the first time that protection against Brucella-challenge can be achieved by combining a commonly used vaccine with a novel oral delivery system such as alginate-vitelline protein B microencapsulation. This system is a potential improvement for efficacious Brucella-vaccine delivery to wildlife in the GYA.
authors.affiliation: Department of Veterinary Pathobiology, Texas A&M University and Texas Agricultural Experiment Station, College Station, Texas 77845-1114, USA. aarenas@cvm.tamu.edu
authors.forename: Angela M
authors.initials: AM
authors.lastname: Arenas-Gamboa
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Ficht
authors.forename: Donald S
authors.initials: DS
authors.lastname: Davis
authors.forename: Philip H
authors.initials: PH
authors.lastname: Elzer
authors.forename: Melissa
authors.initials: M
authors.lastname: Kahl-McDonagh
authors.forename: Alfredo
authors.initials: A
authors.lastname: Wong-Gonzalez
authors.forename: Allison C
authors.initials: AC
authors.lastname: Rice-Ficht
mesh_terms: D000284:Administration, Oral; D000818:Animals; D000829:Animals, Domestic; D000835:Animals, Wild; D001428:Bacterial Vaccines / Q000008:administration & dosage*; D002003:Brucella abortus / Q000276:immunology*; D002006:Brucellosis / Q000517:prevention & control / Q000635:transmission / Q000662:veterinary*; D015169:Colony Count, Microbial; D003670:Deer; D004197:Disease Reservoirs / Q000382:microbiology / Q000662:veterinary; D004339:Drug Compounding / Q000662:veterinary; D005260:Female; D011897:Random Allocation; D013045:Species Specificity
chemical_list: D001428:Bacterial Vaccines