Pathogenicity of non-O1/ O139 Vibrio cholerae and its induced immune response in Macrobrachium rosenbergii.

Abstract

Outbreaks of mass mortalities occurred in Macrobrachium rosenbergii farms in Gaoyou county, Jiangsu Province of China. The bacterial isolates from M. rosenbergii exhibited the same phenotypic traits and biochemical characteristics, and were identified as non-O1/O139 Vibrio cholerae according to biochemical characteristics and molecular identification. In challenge test, M. rosenbergii infected with non-O1/O139 V. cholerae GXFL1-4 developed similar pathological signs to the naturally diseased prawns, and LD50 of the strain to M. rosenbergii was 4.5 × 106 CFU/mL at 96 h post-infection. Histopathological analysis revealed that hepatopancreas and intestines of diseased M. rosenbergii exhibited obvious inflammatory responses to non-O1/O139 V. cholerae infection. Detection virulence factors of the strain GXFL1-4 showed that the bacteria produced caseinase, lipase, amylase, lecithinase and hemolysin, and carried toxR, hlyA, ompW, ompU, hap, rtxA and rtxC virulence related genes, supporting the strong virulence to M. rosenbergii. Additionally, the immune related gene expression in M. rosenbergii evaluated by qRT-PCR analysis showed that HSP70, Crustin, Lysozyme, TRL1, ALF1, Lectin, Peroxinectin, proPO and SOD immune related genes were significantly up-regulated at 6 and 12 h after infection with GXFL1-4. The results of our study suggested that non-O1/O139 V. cholerae was an etiological element in the mass mortalities of M. rosenbergii and this study provided preliminary insights into the diversity in the immune response of M. rosenbergii to the bacterial invasion.

• Authors: Xiaojian Gao, Zhen Miao, Xixi Li, Nan Chen, Wenwen Gu, Xiaodan Liu, Hui Yang, Wanhong Wei, Xiaojun Zhang
• Journal: Fish & shellfish immunology (Fish Shellfish Immunol) Vol. 92 Pg. 300-307 (Sep 2019) ISSN: 1095-9947 [Electronic] England
• PMID: 31202968 (Publication Type: Journal Article)
• Copyright: Copyright © 2019 Elsevier Ltd. All rights reserved.

Chemical References

• Arthropod Proteins

Topics

• Animals
• Arthropod Proteins (immunology)
• Immunity, Innate (genetics)
• Palaemonidae (genetics, immunology)
• Vibrio cholerae non-O1 (physiology)