China Animal Husbandry and Veterinary Medicine ›› 2023, Vol. 50 ›› Issue (7): 2906-2914.doi: 10.16431/j.cnki.1671-7236.2023.07.030

• Preventive Veterinary Medicine • Previous Articles     Next Articles

Bioinformatics Analysis and Immunogenicity Evaluation of Brucella Outer Membrane Vesicles

XU Zhenyu1,2, XU Jinfeng2,3, DENG Xiaoyu1,2, WANG Yueli1,2, HE Jinke4, XIE Shanshan1,2, WANG Zhen1,2, YI Jihai1,2, WANG Yong1,2, MIAO Yuhe5, CUI Lijin5, CHEN Chuangfu1,2   

  1. 1. College of Animal Science and Technology, Shihezi University, Shihezi 832000, China;
    2. Collaborative Innovation Center for Healthy Breeding and Prevention and Control of Human-Veterinary Diseases in Sheep, Shihezi 832000, China;
    3. Wuwei Vocational College, Wuwei 733000, China;
    4. Xinjiang Second Medical College, Karamay 835000, China;
    5. Fujian Shengwei Biotechnology Co., Ltd., Nanping 350000, China
  • Received:2022-12-09 Published:2023-06-30

Abstract: 【Objective】 The purpose of this experiment was to explore the prospects of Brucella outer membrane vesicles (OMVs) for use in subunit vaccines, prepare subunit vaccines of Brucella OMVs, and assess the immunogenicity of Brucella OMVs.【Method】 OMVs of Brucella melitensis were prepared by high-speed centrifugation, and the morphological and fractional analyses of the prepared OMVs were performed by transmission electron microscopy, SDS-PAGE and bioinformatics analysis.Mice were immunized after emulsification of OMVs using nanoadjuvant (LDH) and Freund's adjuvant, and the specific antibodies were detected by indirect ELISA method for OMVs at 7, 14, 21, 28 and 35 d after immunization, and the IgG antibody levels in serum of mice post-immunization were detected using the mouse IgG ELISA kit, so as to assess the level of humoral immunity induced by OMVs.The level of cellular immunity induced by OMVs was assessed by isolation of mouse spleen lymphocytes with cytokine (IL-4 and IFN-γ) assay and flow cytometry assay of T lymphocyte subpopulations in the peripheral blood of mice.【Result】 The OMVs were successfully extracted and purified, with diameters ranging from 20 to 160 nm.Bioinformatics analysis showed that the main constituent proteins of OMVs, OMP25, OMP31, OMP16, OMP19, BP26 and SOD were hydrophilic and antigenic proteins, and there were several B and T cell dominant.Compared with PBS group, after immunization with OMVs, the different adjuvant groups induced high levels of specific and IgG antibodies in mice (P<0.01).Meanwhile, OMVs significantly induced IFN-γ production in mouse spleen lymphocytes (P<0.05), and promoted the expression of CD4+ T cells (P<0.05).【Conclusion】 This study confirmed that Brucella OMVs of sheep species had strong immunogenicity and could induce strong humoral and cellular immune responses in mice, laid a theoretical foundation for the development of a new subunit vaccine for Brucella.

Key words: Brucella; outer membrane vesicles (OMVs); immunogenicity

CLC Number: