title: Effect of a new recombinant Aeromonas hydrophila vaccine on the grass carp intestinal microbiota and correlations with immunological responses.
abstract: Intestinal microbiota has become an integral component of the fish, and plays a key role in host metabolism, immunity and health maintenance. However, information on the immune responses after vaccine administration in relation to the intestinal microbiota is absent in fish. The present study focused on the effect of a new recombinant Aeromonas hydrophila vaccine (Aera) by using a novel functionalized, single-walled carbon nanotubes (SWCNTs) as a delivery vehicle on the intestinal microbiota of grass carp (Ctenopharyngodon idella) through the bath immunization, and further explored the immunological responses in intestine, kidney and spleen. By performing deep sequencing, a total of 81,979 valid reads and 609 OTUs obtained from 4 intestine samples were analyzed. We detected 141 genuses, most of which belonged to Firmicutes, Fusobacteria and Proteobacteria. Of note, the quantity of Aeromonas in library Aera (after 6 h Aera vaccine pretreatment, fish were transferred to tanks without SWCNTs-Aera for 28 d) and Aera-GD (6 h Aera vaccine pretreated prior to the group injected by A. hydrophila) was declined 6.5% and 14.6% compared with the control, respectively. Moreover, the expression of seven immune-related genes (IFN-I, TNF-α, CRP, IL-8, IgM, MHC I and CD8α) in the intestine, kidney and spleen of Aera treated fish was significantly enhanced, which indicated that a better tissue immune response in grass carp was induced by the SWCNTs-Aera vaccine. Therefore, a new recombinant SWCNT-Aera vaccine may represent potentially efficient and immunological role in grass carp intestine to resist A. hydrophila infection.
authors: Northwest A&F University, Yangling 712100, People's Republic of China.
authors: Lei
authors: L
authors: Liu
authors: Northwest A&F University, Yangling 712100, People's Republic of China.
authors: Yu-Xin
authors: YX
authors: Gong
authors: Northwest A&F University, Yangling 712100, People's Republic of China.
authors: Bin
authors: B
authors: Zhu
authors: Northwest A&F University, Yangling 712100, People's Republic of China.
authors: Guang-Lu
authors: GL
authors: Liu
authors: Northwest A&F University, Yangling 712100, People's Republic of China. Electronic address: wanggaoxue@126.com.
authors: Gao-Xue
authors: GX
authors: Wang
authors: Northwest A&F University, Yangling 712100, People's Republic of China. Electronic address: feiling@nwsuaf.edu.cn.
authors: Fei
authors: F
authors: Ling
mesh_terms: D016980:Aeromonas hydrophila / Q000276:immunology*; D000818:Animals; D001428:Bacterial Vaccines / Q000276:immunology*; D002347:Carps; D004269:DNA, Bacterial / Q000235:genetics / Q000378:metabolism; D005393:Fish Diseases / Q000382:microbiology / Q000517:prevention & control*; D000069196:Gastrointestinal Microbiome; D016905:Gram-Negative Bacterial Infections / Q000382:microbiology / Q000517:prevention & control / Q000662:veterinary*; D007113:Immunity, Innate; D012336:RNA, Ribosomal, 16S / Q000235:genetics / Q000378:metabolism; D014614:Vaccines, Synthetic / Q000276:immunology
chemical_list: D001428:Bacterial Vaccines; D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S; D014614:Vaccines, Synthetic
keywords: Aeromonas hydrophila; Bath immunization; Immune response; Intestine microbiome; SWCNT vaccine