Beta-2-Microglobulin, 1 x 96 Assays

FOR RESEARCH USE ONLY.

Product Name: Beta-2-Microglobulin

Sample Type: Serum

# of Samples: 1X96 Assays

Intended Use: The GenWay Biotech 2-Microglobulin ELISA is intended for the quantitative determination of 2-microglobulin in human serum. This assay is for use as an aid in the diagnosis of kidney disease.

Introduction: Beta-2-microglobulin (?2-MG) is expressed by the nucleated cells of the body and on many tumor lines. Human ? 2-MG is a low molecular weight protein (MW 11600) consisting of a single polypeptide chain of 99 amino acids.1,2 It is identical to the small chain of the HLA-A, -B, and -C major histocompatibility complex antigens.3-5 In structure and amino acid sequence, it resembles the CH3 region of IgG, though it is antigenically distinct.
?2-MG is eliminated via the kidneys. After filtration through the glomeruli, it is reabsorbed and catabolized by the proximal tubular cells through endocytosis.6 It is found at low levels in the serum and urine of normal individuals. Typically only trace amounts of 2-MG are excreted in the urine and higher rates are interpreted as evidence of tubular dysfunction. Urinary excretion is markedly increased in tubulointerstitial disorders, and where aminoglycosides and anti-inflammatory compounds are present.7-9 ?2-MG is also excreted in increased amounts in the urine of patients with upper urinary tract infections10 and connective-tissue diseases such as rheumatoid arthritis and Sjogren�s syndrome.^11
Elevated serum concentrations in the presence of normal glomerular filtration rate suggest increased ?2-MG production or release. In patients with rheumatoid arthritis^12, systemic lupus erythematosus^13, sarcoidosis^14 and some viral diseases including cytomegalovirus, non-A and non-B hepatitis and infectious mononucleosis,^15,16 the ?2-MG serum level changes in relation to disease activity.
The GenWay Biotech ?2-MG ELISA provides a sensitive and reliable assay for the measurement of ?2-microglobulin in human serum. The kit features a standard range of 0.625 to 10 Ag/ml and will determine a minimum detectable concentration of 0.1 Ag/ml. The assay provides results in less than 2 hours in a microtiter plate format.

Principles of the assay: The GenWay Biotech ?2-MG ELISA test is based on the principle of a solid phase enzyme-linked immunosorbent assay (ELISA). The assay system utilizes a monoclonal anti- ?2-MG antibody for solid phase immobilization (on the microtiter wells). A sheep anti- ?2-MG antibody is in the antibody-enzyme (horseradish peroxidase) conjugate solution. The diluted test sample is allowed to react first with the immobilized antibody for 30 minutes at 37C. The sheep anti- ?2-MG-HRPO conjugate is then added and reacted with the immobilized antigen for 30 minutes at 37C, resulting in the ?2-MG molecules being sandwiched between the solid phase and enzyme-linked antibodies.
The wells are washed with water to remove unbound-labeled antibodies. A solution of TMB is added and incubated for 20 minutes at room temperature, resulting in the development of a blue color. The color development is stopped with the addition of 1N HCl, changing the color to yellow. The concentration of ?2-MG is directly proportional to the color intensity of the test sample. Absorbance is measured spectrophotometrically at 450nm.

Storage and Stability: 1. Store the unopened kit at 2-8C upon receipt and when it is not in use, until the expiration shown on the kit label. Refer to the package label for the expiration date.
2. The opened and used reagents are stable until the expiration date if stored properly at 2-8C.
3. Keep microtiter plate in a sealed bag with desiccant to minimize exposure to damp air.

Limitation of the Test: 1. Reliable and reproducible results will be obtained when the assay procedure is carried out with a complete understanding of the package insert instructions and with adherence to good laboratory practice.
2. The results obtained from the use of this kit should be used only as an adjunct to other diagnostic procedures and information available to the physician.
3. Serum samples demonstrating gross lipemia, gross hemolysis, or turbidity should not be used with this test.
4. The wash procedure is critical. Insufficient washing will result in poor precision and falsely elevated absorbance readings.