Serum smooth muscle autoantibodies (SMA) react with different proteins (actin, tubulin, vimentin, desmin, cytokeratins) of the cytoskeletal components (microfilaments, microtubuli, intermediate filaments). Their detection can be the hallmark of autoimmune diseases such as autoimmune hepatitis (AIH) or celiac disease; however, they can also be observed in viral diseases such as chronic hepatitis C and infectious mononucleosis. When present at high titers (> 1:80), they are considered sensitive markers of AIH, being found in up to 80% of cases. Within the spectrum of SMA, antiactin antibodies are the most specific for the diagnosis of AIH, whereas no convincing evidence of their pathogenetic or prognostic value has been provided yet. SMA of the immunoglobulin (Ig)A class with antiactin specificity have been described in a large majority of celiac patients with severe mucosal damage. The classical immunomorphologic techniques remain the gold standards for SMA testing; in addition, the new immunochemical tests with purified antigens appear to be a promising complementary approach.
Smooth Muscle Autoantibodies (Chapter 58)
MURATORI, LUIGI;
2014
Abstract
Serum smooth muscle autoantibodies (SMA) react with different proteins (actin, tubulin, vimentin, desmin, cytokeratins) of the cytoskeletal components (microfilaments, microtubuli, intermediate filaments). Their detection can be the hallmark of autoimmune diseases such as autoimmune hepatitis (AIH) or celiac disease; however, they can also be observed in viral diseases such as chronic hepatitis C and infectious mononucleosis. When present at high titers (> 1:80), they are considered sensitive markers of AIH, being found in up to 80% of cases. Within the spectrum of SMA, antiactin antibodies are the most specific for the diagnosis of AIH, whereas no convincing evidence of their pathogenetic or prognostic value has been provided yet. SMA of the immunoglobulin (Ig)A class with antiactin specificity have been described in a large majority of celiac patients with severe mucosal damage. The classical immunomorphologic techniques remain the gold standards for SMA testing; in addition, the new immunochemical tests with purified antigens appear to be a promising complementary approach.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
