Salmonella Choleraesuis outer membrane vesicles: Proteomics and immunogenicity

Area of Science:

• Microbiology
• Immunology
• Veterinary Science

Background:

• Salmonella enterica serotype Choleraesuis (S. Choleraesuis) causes significant economic losses in swine production.
• Bacterial outer membrane vesicles (OMVs) are crucial in pathogen interactions and virulence.
• Understanding S. Choleraesuis OMVs can reveal insights into pathogenicity and host-pathogen dynamics.

Purpose of the Study:

• To purify and characterize OMVs from S. Choleraesuis strain χ3545.
• To identify proteins and lipopolysaccharide (LPS) profiles within these OMVs.
• To evaluate the immunogenicity and protective potential of S. Choleraesuis OMVs in a mouse model.

Main Methods:

• Purification and characterization of OMVs from S. Choleraesuis.
• Lipopolysaccharide (LPS) profiling and LC-MS/MS for protein identification (192 proteins identified).
• Immunization experiments in mice (intranasal and intraperitoneal routes) followed by immune response assessment and challenge.

Main Results:

• Purified OMVs contained intact LPS and were rich in outer membrane and cytoplasmic proteins, including immunoreactive and multi-drug resistance-associated proteins.
• S. Choleraesuis OMVs elicited significant humoral and mucosal immune responses in mice.
• While not providing complete protection, OMVs vaccination prolonged survival time in mice challenged with a high dose of S. Choleraesuis.

Conclusions:

• S. Choleraesuis OMVs possess immunogenic properties and can induce protective immune responses.
• OMVs may serve as a valuable component for developing novel vaccines against S. Choleraesuis.
• Further research into OMV pathogenicity and function is warranted for S. Choleraesuis.