What is the Difference Between Primary and Secondary Antibody?
🆚 Go to Comparative Table 🆚The main difference between primary and secondary antibodies lies in their binding capabilities:
- Primary antibodies bind directly to a particular antigen, such as the target protein in an experiment. They are typically produced as monoclonal (mAbs) or polyclonal antibodies. Primary antibodies can be used for various purposes, such as detecting biomarkers for diseases or studying the absorption, distribution, metabolism, and excretion (ADME) of therapeutic agents.
- Secondary antibodies bind to the primary antibody instead of binding to the target antigen. They aid in the detection, sorting, or purification of target antigens. Secondary antibodies provide signal detection and amplification, as well as extended utility, since a given secondary antibody can be used with any primary antibody of the same type and host species. They are especially efficient in immunolabeling, where the primary antibody's Fab domain binds to an antigen and exposes its Fc domain to the secondary antibody.
Both primary and secondary antibodies can be either monoclonal or polyclonal antibodies. The choice between using a primary or secondary antibody depends on the antibody detection method, such as direct or indirect detection. When using secondary antibodies, it is essential to choose a primary antibody raised in a different species than the sample to avoid cross-reactivity. Additionally, the host species used to raise the secondary antibody must be different from that of the primary antibody.
Comparative Table: Primary vs Secondary Antibody
Here is a table summarizing the differences between primary and secondary antibodies:
| Feature | Primary Antibodies | Secondary Antibodies |
|---|---|---|
| Binding | Bind directly to the target antigen | Bind to the primary antibody |
| Specificity | Specific for the target antigen | Specific for the primary antibody |
| Host Species | Produced in a specific host species | Produced in a different host species than the primary antibody |
| Antibody Detection | Facilitate detection of the target antigen | Enhance detection by allowing the use of signal-producing molecules |
| Amplification | No amplification | Signal amplification due to multiple secondary antibodies binding to a single primary antibody |
Primary antibodies are generated through a combination of in vivo and in vitro technologies, such as hybridoma generation, single B cell sequencing, and polyclonal antibody sequencing. Secondary antibodies are generated by immunizing a host animal with antibodies from a different species, such as injecting rabbit antibodies into a goat to produce goat anti-rabbit antibodies. Common host species for secondary antibody production include goats, donkeys, and rabbits.
- Primary vs Secondary Immune Response
- Antiserum vs Antibody
- Immunoglobulin vs Antibody
- Monoclonal Antibodies vs Polyclonal Antibodies
- Primary vs Secondary Immunodeficiency Disorders
- Primary vs Secondary Tuberculosis
- Antigen vs Antibody
- Antibodies vs T Cells
- Primary vs Secondary Standard Solution
- Complete vs Incomplete Antibodies
- Primary vs Secondary Cells
- Primary vs Secondary Sjogren’s Syndrome
- Primary vs Secondary Lymphoid Organs
- Primary vs Secondary Cell Culture
- Neutralizing vs Binding Antibodies
- Primary vs Secondary Active Transport
- Antigen vs Antibody Test
- Primary vs Secondary Alcohol
- Primary vs Secondary Care