ANA Screen 8 ELISA Kit

Sample

Serum or plasma (EDTA, citrate)

Detection Method

iELISA

Intended Use

Enzyme immunoassay for the qualitative screening of IgG antibodies against dsDNA, RNP, Sm, SS-A/Ro, SS-B/La, Scl-70, CENP-B and Jo-1 in human serum or plasma (EDTA, citrate).

Contents of Kit

1. MTP 1 Microtiter Plate, coated with a mixture of the above antigens, hermetically packed in a foil laminate pouch together with a desiccant bag. The plate consists of 12 strips, each of which can be broken into 8 individual wells.
2. SAMPLEDIL Sample Diluent, 100 mL, ready-to-use, orange coloured. Contains Tris-buffered saline (TBS), bovine serum albumin (BSA), Tween and Na-azide.
3. WASHBUF CONC Wash buffer, 100 mL, 10x-concentrate, blue coloured. Contains TBS, Tween and bromonitrodioxane.
4. CONTROL + CONTROL - Negative and Positive Control, 3.0 mL each, ready-to-use, green and red coloured, respectively. Contain TBS, BSA, Tween and Na-azide.
5. ENZCONJ IgG Enzyme Conjugate, 14 mL, ready-to-use, red coloured. Buffered solution containing stabilising protein, methylisothiazolone and bromonitrodioxane.
6. TMB SUBS TMB Substrate Solution, 14 mL, ready-to-use, colourless. Contains a buffered solution of TMB and H₂O₂. Contained in a vial impermeable to light.
7. STOP TMB Stop Solution (0.2 M H₂SO₄), 14 mL, colourless, ready-to-use. Caution: sulfuric acid is corrosive.
8. Instructions for Use
9. Lot-specific certificate of analysis

Storage

Store kit at 2 - 8°C, do not freeze. It is stable up to the expiry date stated on the label of the box. Do not use kit beyond its expiry date.

Precision

For the assessment of the test precision, the variability of results under the following conditions was determined: a. within 1 assay and between 3 assays, b. between 3 operators and c. between 2 kit lots.
a. Intra- and inter-assay variability (n = 24 and 72, respectively)

b. Operator to operator variability (n = 12)

c. Variability between 2 kit lots (n = 6)

Detection Limit

The detection limit is defined as that concentration of analyte that corresponds to the mean absorbance of sample buffer plus 3-fold standard deviation (s). It was determined as < 0,3 (ratio; n = 24).
Recommended measuring range: 0,4 < ratio < 6

General Description

Circulating autoantibodies against various intracellular antigens (antinuclear antibodies, ANA) are characteristic for systemic, autoimmune-mediated rheumatic diseases of the connective tissue (1, 2, 3, 4). These comprise Systemic Lupus Erythematosus (SLE), Mixed Connective Tissue Disease (MCTD), Sjögren's Syndrome (SS) A and B, Progressive Systemic Sclerosis (PSS, Scleroderma)/CREST Syndrome and Polymyositis (PM).
The diagnosis of the above disorders is often difficult, due to overlapping symptoms, and therefore usually supported by measuring their associated autoantibodies. 8 antigens specifically recognised by these antibodies are immobilised on the solid phase of the present enzyme-linked immunosorbent assay (ELISA): dsDNA plasmid, RNP(proteins A, C,68kDa), Sm (proteins B, B', D), SS-A/Ro(60kDa-protein), SS-B/La, Scl-70 (DNA-topoisomerase 1), CENP-B (centromere protein B), Jo-1(Histidyl-tRNA-synthetase).
The test is designed for the qualitative, summary determination of the respective autoantibodies (IgG) in human serum or plasma (cf. section 7), without the ability to discriminate between them. It is intended as initial screen test for an overall diagnosis of the above disorders. The test is fast (incubation time 30 / 30 / 30 minutes) and flexible (divisible solid phase, ready-to-use reagents). A negative and a positive control check the assay performance. The positive control also serves as calibrator for assay evaluation.
Intended Purpose
ANA Screen 8 IgG ELISA is an enzyme-linked immunosorbent assay (ELISA) intended for the qualitative, summary determination of IgG class antibodies directed against double-stranded DNA, U1-RNP complexes (proteins A, C, 68kDa), Sm, SS-A/Ro 60, SS-B/La, Scl-70 (DNA-topoisomerase 1), CENP-B (centromereprotein B) and Jo-1 (Histidyl-tRNA synthetase) in human serum or plasma samples.
Its function is the initial screening of patients with suspected systemic, inflammatory autoimmune-mediated rheumatic diseases of the connective tissue, like systemic lupus erythematosus, mixed connective tissue disease (MCTD, Sharp syndrome), Sjögren's Syndrome, Scleroderma (progressive systemic sclerosis, CREST Syndrome), polymyositis and dermatomyositis.