Introduction
Polyclonal
antibodies (pAbs) are a diverse group of antibodies generated from B cells that
are used in the adaptive immune system. Unlike monoclonal antibodies (mAbs),
which all recognise the same epitope per antigen, polyclonal antibodies (pAbs)
recognise numerous epitopes on a single antigen. The usage of pAbs is
beneficial because of their heterogeneous binding, which results in larger
sensitivity ranges than mAbs in many applications.
Polyclonal Antibodies
Polyclonal
antibodies are a collection of antibodies generated by various B cell clones.
When an antigen (a foreign substance or pathogen) enters the body, the immune
system activates a variety of B cells, each of which has the ability to produce
antibodies with somewhat varying binding specificities. As a result, pAbs are
an extremely varied group of antibodies each recognizing a different epitope (a
specific region on the antigen's surface).
The Significance of Polyclonal
Antibodies
1) Broad Binding Specificity
When
compared to monoclonal antibodies, polyclonal antibodies exhibit a greater
variety of binding specificities. This property makes them useful for
identifying different epitopes on an antigen, improving the likelihood of
precise target identification.
2) High Affinity
Because of
their variety, pAbs frequently have a high affinity for their target antigens.
This improved binding can be very useful in tests and diagnostics.
3) Rapid response
When the
immune system encounters an antigen, it produces a wide variety of antibodies
in a short amount of time. This rapid response is essential in the early stages
of infection.
4) Cost-Efficiency
Because pAbs
do not require lengthy cell culture and cloning processes, they can be more
cost-effective than mAbs.
Production of Polyclonal Antibody
Polyclonal
antibodies are created by immunising an animal, often a rabbit, goat, or sheep,
and then collecting the antibodies produced by the animal's immunological
reaction. step by step manufacturing process is listed down below.
1) Antigen Selection
The first
step is to choose the right antigen, which is the molecule that the polyclonal
antibodies will recognise. This might be a protein, peptide, virus, or another
type of target.
2) Immunisation
The antigen
is injected into the selected animal (usually mice) under controlled and
monitored conditions to stimulate the immune system to create antibodies to the
antigen.
3) Serum Collection
Blood
samples are collected from the immunised animal at predetermined intervals. The
concentration of antibodies in the serum rises as the immune response advances.
4) Separation of Serum
Blood
samples are centrifuged to separate serum from cellular components.
5) Purification
The antibody
combination serum is purified to eliminate impurities and unwanted proteins,
making polyclonal antibodies more specific and pure.
6) Testing and characterization
Purified
polyclonal antibodies are tested and characterised to validate their
specificity and affinity for the target antigen. For this goal, many assays and
procedures, including as ELISA and Western blotting, are used.
7) Storage
The final
purified polyclonal antibodies are aliquoted and kept under proper conditions
to maintain their stability and effectiveness.
