Validation of a multi-analyte panel with cell-bound complement activation products for systemic lupus erythematosus

Area of Science:

• Immunology
• Clinical Diagnostics
• Biochemistry

Background:

• Systemic lupus erythematosus (SLE) diagnosis relies on a combination of clinical and serological markers.
• Accurate and reliable diagnostic assays are crucial for timely SLE management.
• Current diagnostic methods may have limitations in sensitivity or specificity.

Purpose of the Study:

• To analytically validate a novel multi-analyte assay panel for the diagnosis of SLE.
• To assess the performance characteristics of the assay panel, including stability and reproducibility.
• To provide clinicians with a tool to aid in SLE diagnosis.

Main Methods:

• Quantitative flow cytometry was used to measure erythrocyte-bound C4d (EC4d) and B-lymphocyte-bound C4d (BC4d).
• Immunoassays were employed for the detection of autoantibodies, including antinuclear and anti-double stranded DNA antibodies.
• Analytical validity was assessed through intra-day and inter-day coefficient of variation (CV) and post-phlebotomy stability studies.

Main Results:

• EC4d and BC4d demonstrated stability for up to 2 days at ambient temperature and 4 days at 4°C.
• Median intra-day CV ranged from 2.9% to 7.8%, and inter-day CV ranged from 7.3% to 12.4%.
• The assay panel showed a low quality control failure rate (<3%) and a positive test result incidence of 13.4% in a large cohort.

Conclusions:

• The analytical validity of the multi-analyte assay panel for SLE diagnosis has been successfully established.
• The assay panel exhibits robust performance characteristics, including stability and reproducibility.
• This validated panel offers a promising tool for assisting clinicians in the diagnosis of SLE.