The key difference between monoclonal antibodies and polyclonal antibodies is that monoclonal antibodies are made using identical immune cells, while polyclonal antibodies are made using several different immune cells.
Antibodies are very large Y-shaped proteins. They are also called immunoglobulins. Antibodies are produced by B cells due to an adaptive immune response when the immune system encounters a foreign molecule. There are two types of antibodies: monoclonal antibodies and polyclonal antibodies. Monoclonal antibodies bind to the same epitope on a target antigen, while polyclonal antibodies bind to the same antigen but with different epitopes.
CONTENTS
1. Overview and Key Difference
2. What are Monoclonal Antibodies
3. What are Polyclonal Antibodies
4. Similarities – Monoclonal Antibodies and Polyclonal Antibodies
5. Monoclonal Antibodies vs Polyclonal Antibodies in Tabular Form
6. Summary – Monoclonal Antibodies vs Polyclonal Antibodies
What are Monoclonal Antibodies?
Monoclonal antibodies are made by using identical immune cells. Monoclonal antibodies bind to the same epitope on a target antigen. This means they interact with a particular epitope on the antigen. Monoclonal antibodies can be defined as a homogenous population of antibodies that are produced by a single clone of plasma B cells. Their production requires hybridoma cell lines.
Figure 01: Monoclonal Antibodies
All monoclonal antibodies can be traced back to a unique parent cell. It is possible to generate monoclonal antibodies that specifically bind to any substances. Therefore, monoclonal antibodies have become extremely useful in biochemistry, molecular biology, and medicine. Moreover, monoclonal antibodies are used in both the diagnosis and therapy of several diseases, including COVID-19. Furthermore, the advantages of monoclonal antibodies include batch-to-batch high homogeneity, ability to produce in large quantities, high specificity to a single epitope, more sensitivity in assays that need quantification of protein levels, and very lower background notice. The disadvantages are its cost, time-consuming nature, and susceptibility to binding changes when labelled.
What are Polyclonal Antibodies?
Polyclonal antibodies are made using several different immune cells. Polyclonal antibodies bind to the same antigen but different epitopes. Polyclonal antibodies are secreted by different B cell lineages within the body. Polyclonal antibodies are a heterogeneous antibody population. The production of polyclonal antibodies involves the following steps: antigen preparation, adjuvant selection and preparation, animal selection, injection process, and blood serum extraction.
Figure 02: Polyclonal Antibodies
Moreover, polyclonal antibodies are inexpensive, relatively quick to produce, has a high sensitivity for detecting low-quantity proteins, and has a high ability to capture target proteins. They have a higher overall antibody affinity against the antigen due to multiple epitope recognition, bind quickly to the target antigen, easily couple with antibody labels, and are unlikely to affect binding capability. Furthermore, the disadvantages of polyclonal antibodies include batch-to-batch variability due to production in different animals at different times and high chances of cross-reactivity due to the recognition or binding of multiple epitopes.
What are the Similarities Between Monoclonal Antibodies and Polyclonal Antibodies?
- Monoclonal antibodies and polyclonal antibodies are two types of antibodies available to scientists.
- Both are proteins in nature.
- They are extremely useful in biochemistry, molecular biology, and medicine
- Both have advantages and disadvantages.
What is the Difference Between Monoclonal Antibodies and Polyclonal Antibodies?
Monoclonal antibodies are made by using identical immune cells, while polyclonal antibodies are made by using several different immune cells. This is the key difference between monoclonal antibodies and polyclonal antibodies. Furthermore, monoclonal antibodies are a homogenous antibody population, while polyclonal antibodies are a heterogeneous antibody population.
The following table summarizes the difference between monoclonal antibodies and polyclonal antibodies.
Summary – Monoclonal Antibodies vs Polyclonal Antibodies
Monoclonal antibodies and polyclonal antibodies are two types of antibodies that have wide applications in biochemistry, molecular biology, and medicine. Monoclonal antibodies are made by using identical immune cells, while polyclonal antibodies are made by using several different immune cells. This is the key difference between monoclonal antibodies and polyclonal antibodies.
Reference:
1. “What Is Monoclonal Antibody Therapy & Who Is Eligible to Receive It?” Houston Methodist On Health.
2. “Polyclonal Antibodies.” An Overview | ScienceDirect Topics.
Image Courtesy:
1. “Monoclonals” By Adenosine – Own work (CC BY-SA 3.0) via Commons Wikimedia
2. “Biochem-polyclonal production” By Mei.huang at English Wikibooks (CC BY 3.0) via Commons Wikimedia