Anti-sarcolemma

Anti-sarcolemma antibodies are a type of antibodies that can be found in certain medical conditions. They are specifically associated with cardiac muscle disorders and are often detected in patients with conditions such as Dressler's syndrome after myocardial infarction, cardiomyopathy, myocarditis, rheumatic fever, and those who have undergone cardiac surgery. These antibodies can target various antigens, including adenine nucleotide translocator protein, cardiac myosin, and tropomyosin.

Antisarcolemmal (ASAs) are a serologic hallmark of inflammatory heart muscle disease (= Myocarditis) and its sequelae (= any complication or condition that results from a pre-existing illness, injury, or medical intervention).

Myocarditis is inflammation of the heart muscle (myocardium). The inflammation can reduce the heart's ability to pump blood. Myocarditis can cause chest pain, shortness of breath, and rapid or irregular heart rhythms (arrhythmias).

Background of Anti-sarcolemmal Antibody (ASA):

Sarcolemmal, also sarcolemma, is the plasma membrane of the muscle cell and is surrounded by a basement membrane and endomysial connective tissue. Sarcolemma, together with an extracellular layer of carbohydrate and collagenous macromolecules which imparts some mechanical strength, is attached to the tendon or aponeurosis of origin and insertion at the end of the fiber. Sarcolemma is similar to the plasmalemma in biochemical composition, which consists of a lipid bilayer and a thin outer coat of polysaccharide material. The function of sarcolemma in muscle cells is generally the same as the plasma membrane in other eukaryote cells. Substantially, the sarcolemma is a kind of excitable membrane, shares many properties with the neuronal cell membrane and play critical actions in various biological activities. Anti-sarcolemmal antibodies (ASAs) are autoantibodies that have been observed and identified in lymphocyte-mediated cytotoxicity.

The Role of Anti-sarcolemmal Antibody (ASA) in Myocarditis:

Myocarditis is a kind of inflammation and damage of the heart muscle or myocardium with some symptoms, such as an abnormal heartbeat, breath, and chest pain. It has been reported that myocarditis has commonly resulted from viral infections, bacterial infections, autoimmune disorders, and toxins. Several circulating autoantibodies induced by infections have been demonstrated and they may play a crucial role in the progression and induction of myocarditis. Studies reported that ASAs (particularly anti-myolemma antibodies) are identified as a serologic hallmark of inflammatory heart muscle disease and its sequelae. Elevated IgG ASAs derived from the sera show a strong correlation with chronic Chagas myocarditis, which suggested that ASAs might be developed as indicators for myocarditis.

References:

Maisch B, Drude L, Hengstenberg C, Herzum M, Hufnagel G, Kochsiek K, Schmaltz A, Schönian U, Schwab MD. Are antisarcolemmal (ASAs) and antimyolemmal antibodies (AMLAs) "natural" antibodies? Basic Res Cardiol. 1991;86 Suppl 3:101-14. doi: 10.1007/978-3-662-30769-4_10. PMID: 1664204.

Links:

https://www.ouh.nhs.uk/immunology/diagnostic-tests/tests-catalogue/cardiac-muscle-antibodies.aspx

https://www.the-rheumatologist.org/article/know-your-labs/?singlepage=1