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Evaluation of Host-Pathogen Responses and Vaccine Efficacy in Mice
Published on: February 22, 2019
Immunogenicity of iron-regulated outer membrane proteins of Pasteurella multocida B:2 in mice model
1Department of Veterinary Microbiology, CCS Haryana Agricultural University, Hisar 125 004, India.
Abstract:
The present study was conducted to investigate the role of iron-regulated outer membrane proteins (IROMP) of Pasteurella multocida B:2 in mice as potential immunogens. Outer membrane proteins extracted from P. multocida B:2 grown under normal (OMP) and iron-deficient (IROMP) conditions were subjected to discontinuous SDS-PAGE. Nine polypeptides of MW ranging from 85.1 to 16.7 kDa from OMP preparations and two additional polypeptides of MW 95.4 and 89.1 kDa from IROMP preparations were observed with bands of MW 37.2 and 34.7 kDa as major proteins. Mice were immunized twice with OMP, IROMP-enriched fractions and whole cell lysate (WCL) via subcutaneous route at day 0 and 21. Antibody titers were determined from sera collected at weekly interval and protection was studied against challenge using 10(2) cfu of P. multocida two weeks after secondary immunization via intranasal and subcutaneous routes. IROMP and OMP immunized mice provoked significant antibody responses and IROMP induced higher antibody responses. IROMP and OMP immunized mice showed protection (100%) upon intranasal challenge and a protection (84%) following subcutaneous challenge as compared to high mortality (84%) in control mice. These results indicate that OMP enriched with IROMP fractions can be superior means of immunization.
Insights
Iron-regulated outer membrane proteins (IROMP) from Pasteurella multocida B:2 show promise as immunogens. Immunization with IROMP and outer membrane proteins (OMP) induced significant antibody responses and protection against infection in mice.
Area of Science:
- Veterinary Microbiology
- Immunology
- Bacterial Pathogenesis
Background:
- Pasteurella multocida B:2 is a significant pathogen causing severe infections in animals.
- Outer membrane proteins (OMP) are crucial for bacterial-host interactions and are potential vaccine candidates.
- Iron-regulated outer membrane proteins (IROMP) may play a key role in P. multocida virulence and immune evasion.
Purpose of the Study:
- To evaluate the immunogenicity and protective efficacy of P. multocida B:2 iron-regulated outer membrane proteins (IROMP) in a mouse model.
- To compare the immune response and protection elicited by IROMP and non-regulated OMP.
Main Methods:
- Extraction and characterization of outer membrane proteins (OMP) and iron-regulated outer membrane proteins (IROMP) from P. multocida B:2 using SDS-PAGE.
- Immunization of mice with OMP, IROMP-enriched fractions, and whole cell lysate (WCL).
- Measurement of antibody titers and assessment of protection against P. multocida challenge via intranasal and subcutaneous routes.
Main Results:
- Both OMP and IROMP immunization induced significant antibody responses in mice, with IROMP eliciting higher titers.
- Mice immunized with IROMP and OMP showed 100% protection against intranasal challenge and 84% protection against subcutaneous challenge.
- Control mice exhibited high mortality (84%) following challenge, highlighting the efficacy of the OMP and IROMP vaccines.
Conclusions:
- Iron-regulated outer membrane proteins (IROMP) of P. multocida B:2 are potent immunogens.
- OMP, particularly those enriched with IROMP, represent a promising strategy for developing effective vaccines against P. multocida infections.
