Evaluation of a whole cell, p57- vaccine against Renibacterium salmoninarum

Diseases of Aquatic Organisms

Gregory D. Wiens¹  Jon D. Piganelli¹  John M. Christensen¹  , Jia Allen Zhang¹  Stephen L. Kaattari¹ 

关键词: Bacterial kidney disease;    Renibacterium salmoninarum;    p57;    Oral vaccine;   

DOI  :  10.3354/dao036037

学科分类：生物科学（综合）

来源: Inter-Research

【 摘 要 】

ABSTRACT: A whole cell Renibacterium salmoninarum vaccine was developed using 37°C heat treated cells that were subsequently formalin fixed; this treatment reduced bacterial hydrophobicity and cell associated p57. Coho salmonOncorhynchus kisutch were immunized with the p57^- vaccine by either a combination of intraperitoneal (ip) and intramuscular (im) injections or per os. In the first experiment, ip/im vaccination of coho salmon withp57^- cells in Freund's Incomplete Adjuvant (FIA) conferred a statistically significant increase in mean time to death after the salmon were ip challenged with 4.1 x 10⁶ colony forming units (cfu) of R. salmoninarum.There was no significant difference in response between fish immunized with R. salmoninarum cell surface extract in FIA and those immunized with extracellular protein (ECP) concentrated from culture supernatant in FIA. The ip challenge doseresulted in complete mortality of all fish by Day 43. In a second experiment, fish were orally vaccinated with p57^- R. salmoninarum cells encased in a pH protected, enteric-coated antigen microsphere (ECAM). Fish were bathchallenged with 4.2 x 10⁶ cfu ml^-1 on Day 0 and sampled at time points of 0 (pre-challenge), 50, 90, or 150 d immersion challenge. Vaccine efficacy was determined by monitoring the elaboration of p57 in the kidneys of vaccinated andcontrol fish. Fish vaccinated orally demonstrated a significantly lower concentration of p57 (p < 0.01) at Day 150 post challenge compared to fish receiving ECAMs alone. Fish receiving p57^- cells without ECAM coating also showed asignificantly lower p57 level (p < 0.03) versus control. In contrast, fish injected intraperitoneally with the p57^- cells or fish fed p57⁺ R. salmoninarum cells in ECAMs demonstrated no significant difference (p >0.05) versus controls. In summary, these studies suggest the preliminary efficacy of 37°C treatment of R. salmoninarum cells as an oral bacterial kidney disease vaccine.

【 授权许可】

Unknown