Final answer:
Monoclonal antibodies are produced from a single B-cell clone and bind to one epitope, offering high specificity but are costly. Polyclonal antibodies are made by injecting an antigen into an animal, leading to antibodies that bind multiple epitopes, making them less specific but more cost-effective.
Step-by-step explanation:
Fundamental Differences Between Monoclonal and Polyclonal Antibodies
The fundamental difference between monoclonal antibodies (mAbs) and polyclonal antibodies lies in their production and specificity. Monoclonal antibodies are produced from a single B-cell clone and are therefore uniform, binding to a specific single epitope on an antigen. This process involves immunizing an animal, removing B cells from its spleen, and fusing these with myeloma cells to create hybridomas that secrete the desired mAb. Monoclonal antibodies offer high specificity but are expensive and time-consuming to produce.
In contrast, polyclonal antibodies are produced by injecting an antigen into an animal, leading to a mixture of antibodies that recognize multiple epitopes on the same antigen. This results in polyclonal antisera which are less specific, leading to greater cross-reactivity. The sensitivity of polyclonal antibodies makes them more suitable for certain types of assays such as wesatern blots, but their variability can cause issues in diagnostic specificity.
Monoclonal antibodies have higher specificity and consistency compared to polyclonal antibodies, which makes them less likely to exhibit cross-reactivity; however, mAbs are limited by their single-epitope recognition and higher production costs. Polyclonal antibodies, despite their batch-to-batch variability and potential for cross-reactivity, offer advantages in terms of cost and a stronger signal due to binding multiple epitopes.