ENA-4 Profile ELISA Kit (Extractable Nuclear Antigen 4)

Full Name: ENA-4 Profile ELISA Kit (Extractable Nuclear Antigen 4)
Reactivity: Human
Sample Type: Plasma, Serum
Sensitivity: 84.9%

BACKGROUND

Extractable nuclear antigens (ENAs) are designed to be used to detect one or more autoantibodies that can react with cell nucleus proteins. The ENA-IgG profile is typically made up of either of extractable nuclear antigens-4 or extractable nuclear antigens-6 autoantibody tests. There are autoimmune disorders that are specifically linked with the presence of one or more anti-ENA antibodies and it is this association which can be used in the diagnosis of an autoimmune disorder and also in helping to distinguish between disorders.

INTENDED USE

Human ENA-4 profile ELISA kit is designed for detecting in-vitro quantitative profiling of IgG auto-antibodies to extractable nuclear antigens (ENA-4 profile: RNP/Sm, SS-A, SS-B, Sm) in human plasma or serum. This assay has a minimum analytical sensitivity limit of diagn. 84.9%.

Extractable nuclear antigens (ENA-4 profile): RNP/Sm, SS-A (52 and 60 kDa) and SS-B, Sm are bound to the microwells.

CONTENT

All reagents supplied need to be stored at 2 °C – 8 °C, unopened reagents will retain reactivity until expiration date. Do not use reagents beyond this date.

• Divisible Microplate: Consisting of 12 modules of 8 wells each, coated with individual highly purified SS-A, SS-B, Sm and RNP/Sm.
• Positive Control (100 U/ml).
• Negative (0 U/ml).
• Cut-Off Calibrators (25 U/ml): Specific for each individual ENA-4 antigen.
• Sample Buffer (5x).
• Enzyme Conjugate: Consisting of polyclonal rabbit anti-human IgG, labelled with horseradish peroxidase.
• TMB Substrate.
• Stop Solution: 1 M hydrochloric acid.
• Wash Solution (50x).

SENSITIVITY

The minimum detection sensitivity level of IgG antibodies to extractable nuclear antigen-4 profile (ENA-4, ENA IgG) using current ENA-4 profile ELISA kit was diagn. 84.9%. The dynamic range for this assay is to a cut-off index 1.0.

ASSAY CHARACTERISTICS

– Results Interpretation: Negative: < 1.0, Borderline: 1.0 -1.2, Positive: > 1.2.
– Specificity: Highly specific for SS-A (Ro), SS-B (La), Sm and RNP/Sm. No cross-reactivities with other antigens was observed.
– Interfering Substances: No interference with haemolytic (up to 1000 mg/dL), lipemic (up to 3 g/dL triglycerides) or bilirubin (up to 40 mg/dL) containing sera.
– Calibration: Calibrated against the internationally recognised reference sera.

REFERENCES

1. Practical evaluation of methods for detection and specificity of autoantibodies to extractablenuclear antigens. Clin Diagn Lab Immunol. (2004) 11 (2): 297-301. Orton S.M., et al.
2. [Evolution of autoantibodies profile in systemic lupus erythematosus according to age and clinical manifestations]. Ann Biol Clin (Paris). (2014) 72 (3): 351-8. French. Diallo M.S., et al.
3. Comparison of two extractable nuclear antigen testing algorithms: ALBIA versus ELISA/line immunoassay. Pathology. (2016) 48 (5): 491-7. Chandratilleke D., et al.
4. Clinical performance evaluation of a novel rapid response chemiluminescent immunoassay for the detection of autoantibodies to extractable nuclear antigens. Clin Chim Acta. (2013) 424: 141-7. Bentow C., et al.
5. Autoantibody profile in systemic sclerosis. Acta Med Iran. (2010) 48 (1): 12-20. Behmanesh F., et al.

OTHER RELATED ELISA KITS

• ENA Screen ELISA Kit
• ENA-6 Profile ELISA Kit
• ENA Combi ELISA Kit