Table 4

Some immunohistochemical techniques currently available to assist in diagnostic problems in disorders of muscle

Antibody/AntigenMolecular specificityDiagnostic use
HLA, human major histocompatibility complex.
Dystrophin and spectrin (an essential control to monitor membrane integrity)Antibodies are available to the rod domain, C-terminus, and N-terminus, and it is recommended that all three antibodies are used to avoid the possibility of occasional false negative resultsDuchenne and Becker muscular dystrophy
Fetal myosinMyosin is a contractile muscle specific protein composed of two heavy and two light chains. The heavy chain has many isoforms some of which are developmentally regulatedMuscle regeneration
DAGS (dystrophin associated glycoproteins). Spectrin is an essential controlThe dystrophin–glycoprotein complex appears to link dystrophin to the plasma membrane and the laminin component of the extracellular matrix. Antibodies are available against the α, β, γ, and δ components of sarcoglycans of different molecular weight (50 kDa, 43 kDa, 35 kDa, and 35 kDa)Expression of different members of the complex is altered in several types of muscular dystrophy
Merosin laminin. Spectrin is an essential controlAn extracellular matrix component of the DAG complexCongenital muscular dystrophy
CD 68An intracellular glycoprotein primarily associated with cytoplasmic granules and to a lesser extent with cell membranes of macrophages, monocytes, neutrophils, basophils, and large lymphocytesMacrophages
B and T cell markersNumerous antibodies are available for the identification of lymphocyte typesInflammatory disorders and lymphomas
Immunoglobulin heavy and light chainsand complementThese are helpful in establishing whether a lesion is of lymphoid origin, reactive, or malignantIgG, IgM, and complement are particularly useful in the diagnosis of dermatomyositis
HLA class 1Expressed on the surface of most human nucleated cellsMuscular dystrophy, inflammatory myopathy, and neuromuscular disorders