Intended use

Enzyme immunoassay for the detection of autoantibodies IgG against ds DNA.

Background

Systemic lupus erythematosus (SLE) is an autoimmune-mediated, chronic inflammatory disease with variable clinical presentation, ranging from localised skin lesions to a destructive systemic disorder without cutaneous changes. Antibodies to double-stranded (ds) DNA are a well-known, specific marker for SLE with a prevalence from 50-90%, depending on disease severity. Their titre often correlates with disease activity and provides a tool for therapy control. Circulating DNA/anti-DNA immune complexes are considered to play a role in the pathogenesis of SLE. ds DNA-antibodies constitute a SLE criterion according to the American College of Rheumatology (ACR).

Technical information

The EULISA ds DNA IgG is intended for the quantitative or qualitative determination of IgG antibodies in human serum, directed against ds DNA. The immobilised antigen is a highly purified preparation of plasmid ds DNA (>90% in supercoiled state), free from chromosomal DNA and protein (histones). The test is fast (incubation time 30 / 30 / 30 minutes) and flexible (break apart wells, ready-to-use reagents). Six calibrators allow quantitative measurements; a negative and a positive control check the assay performance.

Kit components and storage of reagents

Contents of the kit

1. 1 microwell plate, coated with ds DNA and hermetically packed in a foil laminate pouch together with a desiccant bag.

2. Sample buffer, 100 mL, ready-to-use, orange coloured.

3. Wash buffer, 100 mL, 10 x-concentrate, blue coloured.

4. 6 calibrators, 2.0 mL each; 0, 6.5, 16, 40, 100 and 250 IU ds DNA antibodies (IgG)/mL, ready-to-use, gradually blue coloured.

5. Negative and positive control, 2.0 mL each, ready-to-use, green and red coloured, respectively.

6. Anti-human IgG HRP conjugate, 14 mL, ready-to-use, red coloured.

7. Substrate solution, 14 mL, ready-to-use, colourless.

8. Stop solution (0.5 M H2SO4), 14 mL, colourless, ready-to-use.

9. Directions for use

10. Lot-specific certificate of analysis

All kit components are stored at 2 - 8°C.