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A novel antibody avidity methodology for rapid point-of-care serological diagnosis
Hanna Smolander1, Janne O Koskinen, Raija Vainionpää
1Laboratory of Diagnostic Microbiology, Turku University of Applied Sciences, Lemminkäisenkatu 30, 20520 Turku, Finland. hanna.smolander@helsinki.fi
Insights
A new rapid serological diagnostic method combines antibody bridging and avidity assays. This allows determining infection phase from a single serum sample, improving upon existing techniques.
Area of Science:
- Immunology
- Medical Diagnostics
Background:
- Current serological techniques often require paired samples or multiple dilutions.
- Determining the infection phase accurately is crucial for timely treatment.
Purpose of the Study:
- To introduce a novel methodology for rapid serological diagnosis.
- To combine antibody bridging assay principles with antibody avidity measurement.
- To enable infection phase determination from a single serum sample.
Main Methods:
- Developed assay methods on two immunoassay platforms: time-resolved fluoroimmunoassay and two-photon excitation fluorometry.
- Combined antibody bridging assay with antibody avidity measurement.
- Compared new methods to conventional IgG/IgM and IgG avidity techniques.
Main Results:
- The new methodology determined infection phase using a single serum dilution.
- Avidity results were independent of sample dilution and consistent across platforms.
- The method proved simple, rapid, and suitable for point-of-care testing.
Conclusions:
- The novel methodology offers a significant improvement over current serological diagnostics.
- Enables rapid, single-sample testing for infection phase determination.
- Facilitates point-of-care serodiagnostic testing with accessible analyzers.
Abstract:
A novel methodology is introduced for rapid serological diagnosis. This methodology combines the antibody bridging assay principle with the measurement of antibody avidity. The combination allows the determination of the infection phase with a single dilution of a single sample of serum. This is a significant improvement on current serological techniques which often require either paired-sample testing (IgG/IgM serology) or testing of the sample in several dilutions (IgG avidity testing). Assay methods were developed on two immunoassay platforms; the heterogeneous time-resolved fluoroimmunoassay and the separation-free two-photon excitation fluorometry. The new methods were compared to conventional class-specific IgG/IgM and IgG avidity techniques. The major findings were that the avidity results of the new methodology were independent of the sample dilution (specific antibody concentration in serum) and consistent between immunoassay platforms. This new methodology is simple, rapid, and quick to perform. It provides the possibility of running serodiagnostic tests at point-of-care with bench-top random-access analyzers.
