What does alpha smooth muscle actin do?
Alpha-smooth muscle actin (SMA), an actin isoform that contributes to cell-generated mechanical tension, is normally restricted to cells of vascular smooth muscle, but SMA can also be expressed in certain non-muscle cells, most notably myofibroblasts.
Which cells express alpha smooth muscle actin?
Myofibroblasts. Myofibroblasts express α-smooth muscle actin (α-SMA) and have contractile and secretory properties that are central to controlling tissue architecture [6]. They express a panel of markers that have been correlated with the site of origin.
Where is alpha smooth muscle actin found?
alpha-Smooth muscle (alpha-sm) actin, an isoform typical of smooth muscle cells (SMC) and present in high amounts in vascular SMC, was demonstrated in the cytoplasm of pericytes of various rat and human organs by means of immunocytochemistry at the electron microscopic level.
Is the liver a smooth muscle?
These other tests include: A test for F-actin antibodies. F-actin is a protein found in smooth muscle tissues of the liver and other parts of the body.
What do myofibroblasts do?
Myofibroblasts are the mesenchymal cell type responsible for wound healing and tissue repair across all organs and various physiological states, including cancer [31].
What is actin a marker for?
α-Smooth muscle actin (α-SMA) is used as a marker for a subset of activated fibrogenic cells, myofibroblasts, which are regarded as important effector cells of tissue fibrogenesis.
What causes smooth muscle antibody positive?
Anti-smooth muscle antibodies (ASMAs) attack several structural proteins in smooth muscle, affecting the liver and other tissues. The presence of ASMA in the blood indicates that a person may have autoimmune hepatitis or another disease that damages the liver.
What causes a positive anti smooth muscle antibody?
Detected levels of ASMAs are reported as a titer. Positive AMSA results are greater than or equal to a dilution of 1:40. Along with autoimmune liver disease, a test that comes back positive for ASMAs may also be due to: chronic hepatitis C infection.
Where are myofibroblasts found in the body?
Location. Myofibroblasts were first identified in granulation tissue during skin wound healing. Typically, these cells are found in granulation tissue, scar tissue (fibrosis) and the stroma of tumours. They also line the gastrointestinal tract, wherein they regulate the shapes of crypts and villi.
How are myofibroblasts activated?
Myofibroblastic transcription can also be activated through non-Smad pathways such as ERK and p38 [104, 105]. Revealing a crosstalk between canonical and non-canonical TGF-β pathways, a most recent report showed that TGF-β1 induced human lung fibroblast activation through the Raf1/ERK/Smad pathway [106].
What are the anti smooth muscle antibodies?
Anti-smooth muscle antibody. Anti-smooth muscle antibody is a blood test that detects the presence of antibodies against smooth muscle. The antibody is useful in making a diagnosis of autoimmune hepatitis. Antibodies. An antibody is a protein produced by the body’s immune system when it detects harmful substances, called antigens.
What is smooth muscle AB titer?
Smooth muscle antibodies (SMA) are autoantibodies, proteins produced by the body’s immune system that recognize and attack its own actin, a protein found in smooth muscle and other tissues, especially the liver. This test detects and measures the amount ( titer) of SMA (or antibody against actin) in the blood.
What is an Actin antibody?
An actin antibody is one that reacts against one of the forms of actin, which is highly similar between different species of organisms. Its active form is as filaments. This is how it comprises part of the cytoskeleton and is involved in helping cells and muscles contract. There are three main groups in vertebrate cells — alpha, beta, and gamma.
What is the abbreviation for smooth muscle actin?
How is Smooth Muscle Actin abbreviated? SMA stands for Smooth Muscle Actin. SMA is defined as Smooth Muscle Actin very frequently.