What testing method is commonly used to identify anti-Sm antibodies in patients suspected of SLE?

What testing method is commonly used to identify anti-Sm antibodies in patients suspected of SLE?

• A. Western blot analysis
• B. Multiplex immunoassays
• C. Enzyme-linked immunosorbent assay (ELISA)
• D. Immunohistochemistry

Answer: (C)

The identification of anti-Sm antibodies, which are associated with systemic lupus erythematosus (SLE), is commonly performed using the enzyme-linked immunosorbent assay (ELISA) method. ELISA is a sensitive and specific assay that allows for the detection of antibodies in serum by utilizing an antigen coated onto a plate. In the context of anti-Sm testing, the Sm antigen is bound to the plate, and patient serum is added. If anti-Sm antibodies are present, they will bind to the antigen and can be detected through a secondary antibody that is conjugated to an enzyme, which produces a measurable signal. This method is favored for its high throughput capability and quantitative nature, allowing laboratories to effectively screen for these specific autoantibodies in a patient population. Other methods, such as Western blot analysis and immunohistochemistry, are generally less used for this specific diagnosis because they are not as efficient or widely applicable for detecting circulating antibodies in serum compared to ELISA. Multiplex immunoassays, while useful for simultaneous detection of various antibodies, are not the standard method specifically for anti-Sm antibodies.

The identification of anti-Sm antibodies, which are associated with systemic lupus erythematosus (SLE), is commonly performed using the enzyme-linked immunosorbent assay (ELISA) method. ELISA is a sensitive and specific assay that allows for the detection of antibodies in serum by utilizing an antigen coated onto a plate. In the context of anti-Sm testing, the Sm antigen is bound to the plate, and patient serum is added. If anti-Sm antibodies are present, they will bind to the antigen and can be detected through a secondary antibody that is conjugated to an enzyme, which produces a measurable signal.

This method is favored for its high throughput capability and quantitative nature, allowing laboratories to effectively screen for these specific autoantibodies in a patient population. Other methods, such as Western blot analysis and immunohistochemistry, are generally less used for this specific diagnosis because they are not as efficient or widely applicable for detecting circulating antibodies in serum compared to ELISA. Multiplex immunoassays, while useful for simultaneous detection of various antibodies, are not the standard method specifically for anti-Sm antibodies.