title: Expansion of the in vitro assay for Leptospira potency testing to other serovars: case study with Leptospira Hardjo.
abstract: Evaluation of leptospiral vaccines for potency against Leptospira interrogans serovars Pomona, Icterohaemorrhagiae, Canicola, and Grippotyphosa is accomplished using the hamster potency test method described in 9 CFR 113.101-104. Applicability of this method to evaluation of bacterins developed for immunization against infection with L. interrogans serovar Hardjo or Leptospira borgpetersenii serovar Hardjo is complicated by several issues. Information from research on target host animal efficacy studies and evaluation of the immune response elicited using effective whole-cell bacterin formulations have revealed problems in relating these studies to either hamster-based or other potency testing methods. Future work on serovar Hardjo vaccines employing recombinant proteins will require preliminary testing methods in models other than the host animal. These models may also prove applicable to evaluation of potency for protein-based vaccines. Both an acute lethal infection model and a chronic infection model have been developed using two different strains of serovar Hardjo and will be described.
authors.affiliation: Infectious Bacterial Diseases Research Unit, Agricultural Research Service, USDA, National Animal Disease Center, 1920 Dayton Avenue, Ames, IA 50010, USA. Electronic address: David.Alt@ARS.USDA.GOV.
authors.forename: David P
authors.initials: DP
authors.lastname: Alt
authors.forename: Jennifer
authors.initials: J
authors.lastname: Wilson-Welder
mesh_terms: D000818:Animals; D001428:Bacterial Vaccines / Q000276:immunology* / Q000494:pharmacology*; D006224:Cricetinae; D007921:Leptospira interrogans / Q000276:immunology*; D007922:Leptospirosis / Q000097:blood / Q000276:immunology / Q000517:prevention & control / Q000662:veterinary; D013045:Species Specificity; D064166:Vaccine Potency
chemical_list: D001428:Bacterial Vaccines
keywords: Hamster; Hardjo; Leptospira; Model; Potency; Vaccine