Technical Data
R2997
Ro/SS-A Antigen
Description:
The Ro/SS-A antigen is comprised or an acidic 60kD protein that may also be associated with a RNA ranging in size from 80 to 112 bases. The antigenic activity of the Ro/SS-A antigen appears to be independent of the RNA since the precipitin activity remains after treatment with RNase or separation from the RNA. Anti-Ro/SS-A autoantibodies were described originally as precipitating autoantibodies in sera of Sjogren's Syndrome and Systemic Lupus Erythematosus patients. The presence of autoantibodies against the Ro/SS-A antigen may be used as a diagnostic aid. Elevated levels of Anti-Ro/SS-A have been detected in as high as 96% of Sjogren's Syndrome patients, 49% of patients with Systemic Lupus Erythematosus, 83% of mothers of infants with isolated complete congenital heartblock or Neonatal Lupus Dermatitis, and over 75% of patients with Subacute Cutaneous Lupus. Recently, a strong correlation between low positive levels of Anti-Ro/SS-A and subdinical dry eyes or mouth was found in a substantial portion of an elderly population. In addition, it has been shown that 70% of patients with Ro/SS-A precipitating antibodies also have rheumatoid factor. The titer of rheumatoid factor and the concentration of Anti-Ro/SS-A have been closely correlated in Primary Sjogren's Syndrome. Recent developments in ELISA methodology have increased the sensitivity and the ability of the diagnostician to quantitate patient antibody titers.

Applications:
Suitable for use in ELISA and Immunodiffusion. Other applications not tested.

Recommended Dilution:
ELISA: 1:100
Optimal dilutions to be determined by the researcher.

Titer:
Immunodiffusion: 1:16

Other Autoantibody Activity in the Serum:
The serum exhibits no reactivity at a dilution of 1:100 when tested against purified SSB, SCL, Sm, Sm/RNP, Jo-1, mitochondrial or ribosomal antigens in an ELISA system designed to detect IgG antibody subclasses.

SSA: 9250EU/ml
SSB: 2EU/ml
SCL: 2EU/ml
Sm: 2EU/ml
Sm/RNP: 4EU/ml
Jo-1: 4EU/ml

Interpretation of Results:
Negative: <16EU/ml, Equivocal: 16-20EU/ml, Positive: >20EU/ml

Storage and Stability:
Lyophilized powder may be stored at -20C. Stable for 12 months after receipt at -20C. Reconstitute with sterile ddH2O. Aliquot to avoid repeated freezing and thawing. Store at -20C. Reconstituted product is stable for 12 months at -20C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.
TypeIsotypeCloneGrade
PabIgGPurified
SizeStorageShippingSourceHost
2ml-20CBlue IceHumanHuman
Concentration:
Not determined
Immunogen:
Ro/SS-A antigen. Autoantibody derived from human serum.
Purity:
Purified by fractionation of delipidated and defibrinated donor human serum.
Form
Supplied as a lyophilized powder in PBS, pH 7.4, 0.13M sodium chloride, 0.02% sodium azide. Reconstitute with 2ml ddH2O.
Specificity:
Recognizes human Ro/SS-A Antigen. Specificity is verified by a precipitin line of identity with the CDC-AF reference serum. This product shows no reactivity at a dilution of 1:100 when tested against purified La/SS-B, Sm, Scl-70, Sm/RNP, Jo-1, Mitochondrial or Ribosomal P antigens in an ELISA system designed to detect IgG antibody. Species Crossreactivity: bovine
Intended for research use only. Not for use in human, therapeutic, or diagnostic applications.
1. Mamula MJ, Fox OF, Yamagata H, and Harley JB. "The (Ro) SS-A Autoantigen as an Immunogen Some Anti-(Ro) SSA Antibody Binds IgG." J of Exp Med Vol 86: pg 1889-1901. 2. Rader MD, O'Brien C, Liu Y, Harley JB, and Reichlin M. "Heterogeneity of the (Ro) SSA Antigen, Different Molecular Forms in Lymphocytes and Red Blood Cells." J. Clin. Invest Vol 83: 1989, pg 1293-1298. 3. Harley JB, Kaine JL, Fox OF, Reichlin M, Gruber B. "Ro SSA Antibody and Antigen in Cogenital Complete Heart Block ((Ro) SSA and Heart Block)." University of Oklahoma, Health Science Center, Arthritis and Immunology Program, Oklahoma Medical Research Foundation, pg 1-16. 4. Harley JB, Alexander EL, Bias WB, Fox OF, et al. "Anti-(Ro) SSA and Anti-(La) SSB in Sjogren's Syndrome." Dept of Med, University of Oklahoma, Health Science Center, Arthritis and Immunology Program, Oklahoma Medical Research Foundation, pg 1-35.