Comparative transcriptome analysis reveals the mechanism of β-glucan in protecting rainbow trout (Oncorhynchus mykiss) from Aeromonas salmonicida infection

Fish Shellfish Immunol. 2020 Mar:98:87-99. doi: 10.1016/j.fsi.2019.12.022. Epub 2019 Dec 19.

Abstract

To study the mechanism of β-glucan in immune protection, rainbow trout were fed diets with or without 0.2% β-glucan for 42 days and then infected with Aeromonas salmonicida. After that, spleen tissues were sampled on 4- and 6-days post infection (dpi). Transcriptome analysis was compared between control group (CG, without β-glucan addition) and 0.2% β-glucan group (BG). In CG vs BG, 378 and 406 DEGs were identified on 4 dpi and 6 dpi respectively; furthermore, 46 DEGs were shared on 4 dpi and 6 dpi, enriching in GO terms, such as complement activation, inflammatory response, and metabolic process. KEGG pathway analysis revealed that some DEGs in CG vs BG were involved in immune or metabolic signaling pathways such as complement and coagulation cascades, toll-like receptor signaling pathway, NF-κB signaling pathway, antigen processing and presentation, and platelet activation on 4 or 6 dpi. DEGs, such as fgg, fgb, f5, c9, c3, c5, tlr5, and myd88, were analyzed in CG vs BG on 4 dpi and 6 dpi, implying their potential roles in β-glucan-modulated immunity. These results are beneficial to understand the mechanism of β-glucan in resisting bacteria in fish.

Keywords: Aeromonas salmonicida; Rainbow trout; Spleen; Transcriptome; β-glucan.

MeSH terms

  • Adaptive Immunity / drug effects*
  • Aeromonas salmonicida / physiology
  • Animal Feed / analysis
  • Animals
  • Diet / veterinary
  • Dietary Supplements / analysis
  • Dose-Response Relationship, Drug
  • Fish Diseases / immunology*
  • Fish Diseases / microbiology
  • Gene Expression Profiling / veterinary
  • Gram-Negative Bacterial Infections / prevention & control
  • Gram-Negative Bacterial Infections / veterinary
  • Immunity, Innate / drug effects*
  • Oncorhynchus mykiss / immunology*
  • Protective Agents / administration & dosage
  • Protective Agents / pharmacology*
  • Random Allocation
  • Spleen / drug effects
  • Spleen / immunology
  • Transcriptome*
  • beta-Glucans / administration & dosage
  • beta-Glucans / pharmacology*

Substances

  • Protective Agents
  • beta-Glucans