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Updated: Aug 6, 2026
08:47
Opsonophagocytic Killing Assay to Assess Immunological Responses Against Bacterial Pathogens
Published on: April 5, 2019
Serum opsonins to group B meningococci
H Sjursen1, R Bjerknes, A Halstensen
1Medical Department, University of Bergen, Haukeland Hospital, Norway.
Acta Pathologica, Microbiologica, Et Immunologica Scandinavica. Section C, Immunology
|December 1, 1987
Summary
Serum antibody levels and opsonic activity against serogroup B meningococci significantly increased in patients recovering from disease and in volunteers receiving a novel vaccine. These immune responses remained elevated six weeks post-illness or immunization, indicating vaccine efficacy.
Area of Science:
- Immunology
- Microbiology
- Vaccinology
Background:
- Neisseria meningitidis serogroup B causes significant morbidity and mortality.
- Developing effective vaccines against serogroup B meningococcal disease remains a public health priority.
- Understanding the immune response to serogroup B meningococcal infections and vaccines is crucial for disease prevention.
Purpose of the Study:
- To investigate the production of serum opsonins and antibodies against serogroup B serotype 15 meningococci.
- To compare immune responses in patients recovering from meningococcal disease with those in healthy volunteers immunized with a novel vaccine.
Main Methods:
- Serum opsonic activity was assessed using a flow cytometric phagocytosis assay with fluorescein isothiocyanate-labeled Neisseria meningitidis.
- Serum antibodies to outer membrane complexes were measured via enzyme-linked immunosorbent assay (ELISA).
- Study involved 7 patients with serogroup B meningococcal disease and 7 immunized volunteers.
Main Results:
- Significant increases in serum opsonic activity were observed in patients during convalescence and in immunized volunteers compared to pre-immunization.
- Both patients and vaccinees showed marked increases in IgG, IgM, and IgA antibodies against the test strain.
- A strong positive correlation (r = 0.883) was found between serum opsonic activity and IgG antibody levels.
Conclusions:
- Convalescent sera from patients and sera from vaccinees demonstrated enhanced opsonic activity against serogroup B meningococci.
- The vaccine effectively elicited robust and sustained antibody responses, including IgG, IgM, and IgA.
- Elevated serum opsonic activity and IgG levels suggest a protective immune response following vaccination or natural infection.
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