An effective live attenuated vaccine against Streptococcus agalactiae infection in farmed Nile tilapia (Oreochromis niloticus)

Publication date: Available online 18 November 2019Source: Fish &Shellfish ImmunologyAuthor(s): Defeng Zhang, Yanxia Gao, Qingyong Li, Xiaoli Ke, Zhigang Liu, Maixin Lu, Cunbin ShiAbstractStreptococcus agalactiae is an important pathogen associated with various aquatic animals, especially tilapia. Streptococcosis has greatly limited the healthy development of tilapia aquaculture in recent times. The development of novel effective vaccines is important for the prevention and control of streptococcosis in fish. We previously constructed a non-encapsulated S. agalactiae strain △cps by the in-frame deletion method. Here, we evaluated whether this mutant △cps is safe for tilapia and suitable for protection against streptococcosis. We observed that the △cps strain was non-pathogenic to tilapia, and there was no reversion of virulence when it was passaged in tilapia. Moreover, the △cps strain survived for at least 11 d in the main immune organs of tilapia. The tilapia vaccinated via intraperitoneal (IP) injection with △cps strain induced a high antibody titer, and the IgM antibody levels were significantly higher in the vaccinated group than in the control group. The vaccination protected tilapia against the S. agalactiae challenge with a relative percent survival of 90.47%. In addition, tilapia immunized with the △cps strain showed significantly higher expression level of IFN-γ, IL-1β, MyD88, IgM, and MHC-Iα in the head kidney than those in the co...
Source: Fish and Shellfish Immunology - Category: Biology Source Type: research

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Source: Acta Virologica - Category: Infectious Diseases Authors: Tags: Acta Virol Source Type: research
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Source: Acta Virologica - Category: Infectious Diseases Authors: Tags: Acta Virol Source Type: research
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Source: Journal for Immunotherapy of Cancer - Category: Cancer & Oncology Source Type: research
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Source: The Procedural Pause - Category: Emergency Medicine Tags: Blog Posts Source Type: blogs
(Duke University Medical Center) Researchers have cleared a major obstacle in the development of an HIV vaccine, proving in animal models that effective, yet short-lasting antibodies can be coaxed into multiplying as a fighting force against the virus
Source: EurekAlert! - Infectious and Emerging Diseases - Category: Infectious Diseases Source Type: news
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Source: Veterinary Microbiology - Category: Veterinary Research Source Type: research
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Source: Veterinary Microbiology - Category: Veterinary Research Source Type: research
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Source: Fish and Shellfish Immunology - Category: Biology Source Type: research
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Source: Archives of Virology - Category: Virology Source Type: research
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Source: Molecular Imaging and Biology - Category: Molecular Biology Source Type: research
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