Evaluation of the immunogenicity of an omp A and staphylococcal target of RNAIII activating fusion protein displayed on the surface of Escherichia coli. (November 2019)

• Record Type: Journal Article
• Authors: Song, Baifen; Zhang, Jianxin; Ma, Jinzhu; Feng, Zhenyue; Yu, Liquan; Yu, Yongzhong; Cui, Yudong
• Is Part Of: Microbial pathogenesis. Volume 136(2019)
• Publication Date: 2019-11
• Subjects: Cow mastitis -- Escherichia coli surface display -- Immuno-protection -- Staphylococcus. aureus -- TRAP protein; Pathogenic microorganisms -- Periodicals; Pathology, Molecular -- Periodicals; Communicable Diseases -- microbiology -- Periodicals; Communicable Diseases -- parasitology -- Periodicals; Micro-organismes pathogènes -- Périodiques; Pathologie moléculaire -- Périodiques; Electronic journals; 616.9041
• DOI: 10.1016/j.micpath.2019.103676
• Languages: English
• ISSNs: 0882-4010

Abstract

Abstract: The purpose of this investigation was to construct a recombinant Escherichia coli strain displaying the Staphylococcus aureus target of RNAIII activating protein (TRAP) on its surface, and to investigate the strain for its immunogenicity. The lpp ' omp A and lpp ' ompA-TRA P genes were fused by the overlap polymerase chain reaction and then ligated into expression plasmid pQE30 producing pLO and pLO-TRAP. These two recombinant plasmids were transformed into E. coli XL1-Blue, resulting in XL1-Blue/pLO and XL1-Blue/pLO-TRAP, which were induced to express protein. The expressed TRAP protein was displayed on the surface of XL1-Blue as judged by whole cell ELISA, flow cytometric analysis, and laser scanning confocal microscopy using the lpp'omp A surface display system. ICR mice were intramuscularly immunized with recombinant strains XL1-Blue/pLO and XL1-Blue/pLO-TRAP as well as recombinant protein TRAP. Immunized mice were assessed for anti-TRAP antibody and lymphocytes for secreted IL-4 and IFN-γ by ELISPOT and secreted IL-17A by indirect ELISA. Immunized mice were challenged with S. aureus Newman and HLJ23-1 strains. The results showed both XL1-Blue/pLO-TRAP and TRAP protein immunized mice to produce better cellular and humoral immunity than XL1-Blue/pLO and PBS injected mice. Highlights: Staphylococcus aureus target of RNAIII activating protein (TRAP) located on the bacterial cell wall. C-terminal sequence [amino acids (aa) 155–167] of TRAP is an antigenic epitope with antibodies reactive against the epitope protective in mice infected with S. aureus. A recombinant E. coli strain displaying S. aureus TRAP on its surface was constructed and it can be as a novel, cow mastitis, candidate vaccine.