A solid phase fluorescent immunoassay for the quantitation of the C3 component of human complement

Area of Science:

• Immunology
• Biochemistry
• Clinical Chemistry

Background:

• The complement system, particularly the C3 component, plays a crucial role in immune responses.
• Accurate quantification of C3 in serum is essential for diagnosing and monitoring various diseases.

Purpose of the Study:

• To develop and validate a novel non-competitive assay for determining C3 levels in human serum.
• To establish a rapid and reproducible method for C3 measurement.

Main Methods:

• A non-competitive immunoassay utilizing specific antibodies covalently attached to polyacrylamide beads.
• Detection of C3 using a fluorescently labeled specific antibody.
• Comparison with radial immunodiffusion for validation in healthy adults.

Main Results:

• The assay provides reproducible C3 measurements in serum within the range of 20 mg/dL to 195 mg/dL in 2 hours.
• The method is sensitive, capable of measuring C3 levels as low as 125 ng/mL.
• Excellent agreement was observed between the developed fluorescent immunoassay and radial immunodiffusion.

Conclusions:

• The described non-competitive method offers a rapid, reproducible, and sensitive approach for C3 determination in human serum.
• This assay is suitable for clinical applications requiring accurate C3 quantification.
• The method demonstrates good concordance with established techniques like radial immunodiffusion.