A rapid and highly sensitive solid-phase enzyme immunoassay specific for human fibronectin using a characterized...

Area of Science:

• Biochemistry
• Immunology
• Cell Biology

Background:

• Human fibronectin is a crucial extracellular matrix protein involved in cell adhesion, migration, and tissue repair.
• Accurate quantification of fibronectin is essential for understanding its role in physiological and pathological processes.

Purpose of the Study:

• To develop and validate a solid-phase enzyme immunoassay (EIA) for quantifying human fibronectin.
• To characterize the specificity and performance of the developed immunoassay.

Main Methods:

• Development of a sandwich enzyme immunoassay using a murine monoclonal IgG1 (f-33) as capture antibody and polyclonal rabbit anti-fibronectin as detector antibody.
• Specificity testing against fibronectin from various animal species.
• Mapping of the monoclonal antibody's epitope to the cell-binding region of fibronectin using fragment analysis, immunoblotting, and functional assays.

Main Results:

• The developed EIA demonstrated high specificity for human fibronectin, with no cross-reactivity to fibronectin from eight other species.
• The monoclonal antibody's binding site was localized to the cell-binding region of fibronectin.
• The assay achieved a detection limit of 2 ng/ml.
• Successful quantification of fibronectin in human plasma, urine, cerebrospinal fluid, and cell culture media.

Conclusions:

• A sensitive and specific solid-phase enzyme immunoassay for human fibronectin has been established.
• The assay is suitable for measuring fibronectin levels in diverse biological samples.
• The characterization of the monoclonal antibody provides insights into fibronectin structure-function relationships.