DISCONTINUED – Please see K023-001

REAADS Anti-Cardiolipin (aCL) IgG/IgM is an ELISA test kit for the determination of IgG/IgM anti-cardiolipin antibodies in human serum or plasma in individuals with systemic lupus erythematosus (SLE) and lupus-like disorders (anti-phospholipid syndrome).

Reagents, Storage and Stability

  • Stabilized beef heart cardiolipin (diphosphatidyl glycerol) coated microwells: 96 (12 strips of 8 breakaway wells), with frame.
  • Sample Diluent: 1 bottle (60 ml) (green solution), contains bovine calf serum. Contains sodium azide.
  • aCL IgG Calibrator Sera (1-high, 2-moderate, 3-low) (human): 3 vials (0.250 ml) see vial label for antibody concentration in GPL units. Calibrator 2 should be used when performing single point calibration. Contains sodium azide.
  • aCL IgM Calibrator Sera (1-high, 2-moderate, 3-low) (human): 3 vials (0.250 ml) see vial label for antibody concentration in MPL units. Calibrator 2 should be used when performing single point calibration. Contains sodium azide.
  • aCL IgG Positive Control Serum (human): 1 vial (0.250 ml) see vial label for expected GPL range. Contains sodium azide.
  • aCL IgM Positive Control Serum (human): 1 vial (0.250 ml) see vial label for expected MPL range. Contains sodium azide.
  • aCL Normal Control Serum (human): 1 vial (0.250 ml) see vial label for expected GPL and MPL ranges. Contains sodium azide.
  • anti-human IgG (goat) HRP-Conjugated Antibody Solution: 1 bottle (15 ml) (blue solution).
  • anti-human IgM (goat) HRP-Conjugated Antibody Solution: 1 bottle (15 ml) (red solution).
  • One Component Substrate (TMB and H2O2): 1 bottle (15 ml) ready to use.
  • Stopping Solution: 1 bottle (15 ml) (0.36 N sulfuric acid).
  • Wash Concentrate: 2 bottles (30 ml)  (33X PBS).

Store at 2 – 8°C. Do Not Freeze.

The test is performed as an indirect ELISA. Diluted serum samples, calibrator sera, and controls are incubated in cardiolipin coated microwells, allowing aCL antibodies present in the samples to react with the immobilized antigen. After the removal of unbound serum proteins by washing, antibodies specific for human IgG or IgM labeled with horseradish peroxidase (HRP) are added forming complexes with the cardiolipin bound antibodies. Two enzymeconjugated antibody solutions are provided, one specific for human IgG antibodies and one specific for human IgM antibodies. The concentration of IgG aCL antibodies and IgM aCL antibodies must be determined separately. Following another washing step, the bound enzyme-antibody conjugate is assayed by the addition of tetramethylbenzidine (TMB) and hydrogen peroxide (H2O2) as the chromogenic substrate. Color develops in the wells at an intensity proportional to the serum concentration of aCL antibodies. Results are obtained by reading the O.D. (optical density or absorbance) of each well with a spectrophotometer. Calibrator sera are provided, with the IgG and IgM aCL concentrations expressed in GPL or MPL units, respectively. These units are traceable to the internationally recognized preparations of the Phospholipid Standardization Laboratory, University of Louisville. The user has the option of running either a single point calibrator or a four-point calibration curve. For single point calibration, dividing the concentration value of the calibrator sera by the O.D. value of the calibrator provides a conversion factor (one for IgG and one for IgM aCL). The O.D. values of all the other samples are multiplied by the conversion factors to obtain IgG and IgM aCL antibody concentrations in standard units. One GPL unit is equivalent to 1 µg/ml of an affinity purified standard IgG sample, and one MPL unit is equivalent to 1 µg/ml of an affinity purified standard IgM sample. For multipoint calibration, perform a linear regression analysis with calibrator values against calibrator O.D.s. Control and patient results are determined from the calibration curve.

CATALOG #

TYPE

WELLS

FORMAT

K023-001 IgG / IgM 96 rapid format (15-15-10)
K023-002* IgG / IgM 288 rapid format (15-15-10)
K026-001 IgA 96 rapid format (15-15-10)
K026-006* IgA 288 rapid format (15-15-10)
K11139* IgG 96 extended incubations (30-30-30)
K12747* IgG 288 extended incubations (30-30-30)
K11140* IgM 96 extended incubations (30-30-30)
K12748* IgM 288 extended incubations (30-30-30)
K11141* IgA 96 extended incubations (30-30-30)
K12770* IgA 288 extended incubations (30-30-30)

* This product may require a special order. Please inquire at info@diapharma.com or 1-800-526-5224.

Anti-cardiolipin (aCL) antibodies are associated with the presence of both venous and arterial thrombosis, thrombocytopenia, and recurrent fetal loss. These autoantibodies are frequently found in patients with systemic lupus erythematosus (SLE) and other autoimmune diseases, as well as in some individuals with no apparent previous underlying disease.

What is the clinical significance when samples test positive for the anti-cardiolipin antibodies and are negative for anti-b2GPI?
The aCL assay can detect antibodies of differing specificities. This includes antibodies specific for the cardiolipin molecule itself, and antibodies that are directed against either a cofactor molecule such as b2GPI, or a special binding site created by the interaction of a cofactor with CL. Antibodies directed against CL may be associated with infectious disease, or may be specific for a different cofactor, such as prothrombin. The clinical significance of these antibodies must be assessed in conjunction with the patient’s symptoms, clinical history, and other laboratory findings. Follow-up testing of these patients is recommended in 3-6 months to confirm reactivity. Only b2GPI cofactor dependent antibodies react in the anti-b2GPI assay; these antibodies show a higher correlation with thrombosis and are more specific for the antiphospholipid syndrome.
What are some features of the REAADS anti-Cardiolipin test? The b2GPI test?
The REAADS anti-Cardiolipin test kit and the b2GPI kit are reagent-complete kits. The anti-cardiolipin kit features specific determination of IgG, IgM, and IgA aCL antibodies. The kits are convenient, cost-effective ELISA procedures which give objective, accurate, and reproducible results with short incubations at room temperature.
How does a syphilis infection affect the REAADS anti-cardiolipin test?
Patients with current or prior syphilis infections may have a positive result without increased risk of thrombosis. Anti-cardiolipin antibodies can appear transiently at low levels during many infections. If a patient first tests positive while there are clinical signs of infection, the test should be repeated after an interval of six months.
Summarize the IgG/IgM and IgA REAADS anti-cardiolipin test. What is the normal range?
The test is an indirect ELISA. Diluted serum samples, calibrator sera, and controls are incubated in cardiolipin coated microwells, allowing aCL antibodies present in the samples to react with the immobilized antigen. After their removal of unbound serum proteins by washing, antibodies specific for human IgG, IgM, or IgA labeled with HRP are added forming complexes with the CL bound antibodies. Following another washing step, the bound enzyme-antibody conjugate is assayed by the addition of TMB and H2O2 as the chromogenic substrate. Color develops in the wells at an intensity proportional to the serum concentration of aCL antibodies. The OD is read at 450 nm.

Normal ranges are less than 23 GPL (IgG per liter), less than 11 MPL (IgM per liter), and 22 APL (IgA per liter).