No, ELISA is not a biomarker, but rather a method used to detect and quantify biomarker proteins in biological samples.
ELISA (Enzyme-Linked Immunosorbent Assay) is a laboratory technique used to measure the concentration of a target molecule (e.g., a protein, peptide, antibody, or hormone) in a solution. According to the reference, "ELISAs are useful methods in detecting and quantifying biomarker proteins in serum and biological fluids." The reference also describes how the enzyme-linked sAB binds to the other epitopes to form a sandwich-like complex, and the binding of the antigen and pAB is detected using the activity of an enzyme, which changes the substrate into a colored product. So, while ELISA is used to measure biomarkers, it is not itself a biomarker. A biomarker, on the other hand, is a measurable indicator of a biological state or condition.
| Feature | ELISA | Biomarker |
|---|---|---|
| Definition | A laboratory technique used to detect and quantify substances. | A measurable indicator of a biological state or condition. |
| Function | Measures the amount of a specific substance (often a biomarker). | Indicates a specific biological state or condition (e.g., disease, exposure). |
| Example | ELISA kit used to measure levels of a specific protein. | Prostate-Specific Antigen (PSA) indicating prostate cancer. |
| Relationship | ELISA is a tool used to measure biomarkers. | Biomarkers are the targets that ELISA measures. |
