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Actin, Smooth Muscle (1A4) Mouse Monoclonal Antibody


Quality Level

biological source


antibody form

culture supernatant

antibody product type

primary antibodies


1A4, monoclonal


For In Vitro Diagnostic Use in Select Regions (See Chart)


buffered aqueous solution

species reactivity



vial of 0.1 mL concentrate (202M-94)
vial of 0.5 mL concentrate (202M-95)
bottle of 1.0 mL predilute (202M-97)
vial of 1.0 mL concentrate (202M-96)
bottle of 7.0 mL predilute (202M-98)


immunohistochemistry (formalin-fixed, paraffin-embedded sections): 1:100-1:500







shipped in

wet ice

storage temp.




General description

Actin is a major component of the cytoskeleton and is present in every cell type. Actin can be resolved on the basis of its isoelectric points into three distinctive components: alpha, beta, and gamma in order of increasing isoelectric point. Anti-Smooth Muscle Actin antibody does not stain cardiac or skeletal muscle; however, it will stain myofibroblasts and myoepithelial cells. This antibody could be used together with Muscle Specific Actin to distinguish leiomyosarcoma from rhabdomyosarcoma. In most cases of rhabdomyosarcoma, this antibody gives negative results whereas Muscle Specific Actin is positive in the rhabdomyoblasts. Leiomyosarcomas are positive with both Muscle Specific Actin and Smooth Muscle Actin antibodies.







Actin, Smooth Muscle Positive Control Slides, Product No. 202S, are available for immunohistochemistry (formalin-fixed, paraffin-embedded sections).

Physical form

Solution in Tris Buffer, pH 7.3-7.7, with 1% BSA and <0.1% Sodium Azide

Preparation Note

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Other Notes

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Legal Information

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Certificate of Analysis

Certificate of Origin

Immunofluorescence studies on the structure of actin filaments in tissue culture cells.
E Lazarides
The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society, 23(7), 507-528 (1975-07-01)
P Cooke
The Journal of cell biology, 68(3), 539-556 (1976-03-01)
There are three classes of myofilaments in vertebrate smooth muscle fibers. The thin filaments correspond to actin and the thick filaments are identified with myosin. The third class of myofilaments (100 A diam) is distinguished from both the actin and...
M Kuroda
Biochimica et biophysica acta, 843(3), 208-213 (1985-12-13)
Changes of actin isomers during development and differentiation of chicken gizzard were investigated by polyacrylamide gel electrophoresis. The two-dimensional gel electrophoresis with SDS-polyacrylamide gels in the presence of urea as the second dimension clearly separated three actin isomers which appear...
Sandra Muller et al.
Scientific reports, 9(1), 7250-7250 (2019-05-12)
Native human subcutaneous adipose tissue (AT) is well organized into unilocular adipocytes interspersed within dense vascularization. This structure is completely lost under standard culture conditions and may impair the comparison with native tissue. Here, we developed a 3-D model of...
A M Gown et al.
The Journal of cell biology, 100(3), 807-813 (1985-03-01)
Injection of chicken gizzard actin into BALB/c mice resulted in the isolation of a smooth muscle-specific monoclonal antibody designated CGA7. When assayed on methanol-Carnoy's fixed, paraffin-embedded tissue, it bound to smooth muscle cells and myoepithelial cells, but failed to decorate...

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