Sm antibodies target spliceosome components designated U-snRNP (Uridin-rich small nuclear RiboNucleo-Proteins) that play an important role in mRNA processing. The main Sm antigen is the so-called D1 protein contained in U1, U2, U4, U5 and U6-snRNP.
Sm antibodies are diagnostic markers (ACR criterion) for SLE, with very high specificity (99 %) but low sensitivity for the disease.
Purified from bovine thymus (for more information on our antigens click here)