Calbiotech SSB IgG Elisa Kit

About Calbiotech SSB IgG Elisa Kit

SUMMARY AND EXPLANATION
Systemic autoimmune disease is characterized by the presence of circulating auto-antibodiesdirected to a wide variety of cellular antigens. Systemic lupus erythematosis (SLE), commonlyreferred to as Lupus is the best known of these diseases. Other possible connective tissuediseases include mixed connective tissue disease (MCTD), Sjogren syndrome, sclerodema, andpolymyositis/dermatomyositis. The majority can be diagnosed by clinical presentation and theirantibody profiles to the various antigens involved, which include dsDNA, SM, RNP, SSA, SSBScl-70, Jo1 and Histones. Therefore, immunoassays for autoantibodies are useful for diagnosticand prognostic evaluations of autoimmune disease. The 48 kd phosphoprotein known as SSB(La) is a transcription termination factor for RNA polymerase III. SSB shuttles between nucleusand cytoplasm and exists both free and as a component of the SSA/SSB ribonucleoproteincytoplasmic particle. Autoantibodies to SSB are detected by ELISA in 70-90% of primary and50% of secondary Sjgren syndrome as well as in 25% of SLE and 80% of subacutecutaneous lupus and in the majority of infants with complete heart block. SSB autoantibodies arefound only in sera determined to contain SSA autoantibodies by a sensitive method; thisprobably reflects the association of the SS-A and SS-B antigens in a macromolecular complex.

PRINCIPLE OF THE TEST
Diluted patient serum is added to wells coated with purified antigen. IgG specific antibody, ifpresent, binds to the antigen. All unbound materials are washed away and the enzymeconjugate is added to bind to the antibody-antigen complex, if present. Excess enzymeconjugate is washed off and substrate is added. The plate is incubated to allow the hydrolysis ofthe substrate by the enzyme. The intensity of the color generated is proportional to the amountof IgG specific antibody in the sample.