The La/SS-B antigen is a 47kD ribonucleic protein that is associated with a spectrum of small RNAs (2). La/SS-B appears to be readily susceptible to proteolysis, resulting in many smaller (42, 320, and 270kD) but still immunoreactive polypeptides (3). It has been shown that the La/SS-B antigen primarily resides in the nucleus (2). It appears to be associated with RNA polymerase III transcripts (4). It has also been shown that the La/SS-B antigen shows strong conservation across species (5). Anti-La/SS-B autoantibodies were described originally as precipitating autoantibodies in sera of Sjogren's Syndrome patients and referred to as SjT.(1) A precipitin with the same properties was rediscovered later and termed La and then SS-B. Anti-La/SS-B precipitins.The presence of autoantibodies against the La/SS-B antigen has been advocated as a diagnostic aid in Sjogren's Syndrome patients (6). Autoantibodies against La/SS-B are also commonly found in Systemic Lupus Erythematosus and Subacute Cutaneous Lupus (4). In addition, there appears to be a correlation between anti-La/SS-B and the absence of nephritis in SLE patients. Studies have demonstrated that SLE patients with precipitating Anti-Ro/SS-A antibodies have a high incidence of serious nephritis (53%), while those with both Anti-Ro/SS-A and Anti-La/SS-B have a low (9%) frequency of nephritis (7).
Applications:Suitable for use in Immunodiffusion. Other applications not tested.
Recommended Dilutions:Some assay systems may require more concentrated or more diluted extract. Optimal dilutions to be determined by researcher.
Storage and Stability: Lyophilized powder may be stored at 4°C for short-term only. Reconstitute to nominal volume by adding sterile dH2O, aliquot and store at -20°C. Reconstituted product is stable for 12 months at -20°C. 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.
仕様
Size：10mg
Source Antigen：Calf thymus
Grade：Purified
Purity：Purified by a combination of protein fractionation and column chromatography.Contaminants: Most contaminating antigens have been removed by immunoadsorbent methodology.
Form：Supplied as a lyophilized powder in PBS, 0.02% sodium azide.Reconstitution: Reconstitute with 1ml dH2O. Note: Some precipitate may occur. Will not affect product performance.
Specificity：Activity: Reacts with La/SS-B antisera in immunodiffusion. No reaction is observed with antisera to nRNP, Ro/ SS-A, Sm, Scl-70, or Jo-1 in immunodiffusion. The activity of this product will vary with the assay conditions.
