Understanding Monoclonal, Polyclonal and Recombinant Antibodies (+ considerations for your experiment!)
5
Min Read
In this blog:
- How are monoclonal, polyclonal and recombinant antibodies different?
- What applications can these research antibodies be used in?
- Why is antibody validation important?
What are the key differences between monoclonal, polyclonal and recombinant antibodies?
Immunoglobulins (IgGs) produced by B cells as a key part of the adaptive immune response, antibodies can be used in diagnostics, therapeutics and research applications. Today, we focus on research tool antibodies.
With over 7 million antibodies on the market, understanding the difference between antibody types and is an important step in reagent selection.
As an antibody search engine, ranking products by citation count from over 300 antibody companies, we are deeply involved in the antibody space and have been for the last decade.
Read on for our introductory guide into monoclonal, polyclonal and recombinant antibodies as a place to start in this field or quick recap!
What are the differences between monoclonal, polyclonal and recombinant antibodies?
A brief summary
A monoclonal antibody targets one particular epitope sequence on your target, a polyclonal antibody targets multiple epitopes across the antigen, and a recombinant antibody is produced from an antibody coding sequence. Each type has their advantages and disadvantages in research.
Let’s drill down into what this means in a bit more detail.
What are polyclonal antibodies?
Polyclonal antibodies are comprised of many IgGs, produced by different clones of plasma B cells. As a heterogeneous mix they target multiple epitopes on an antigen as opposed to a single epitope like monoclonals.
How are polyclonals produced and what are their advantages?
These antibodies are produced by immunising an animal such as a goat, rabbit or sheep to trigger the immune response. The immune response generates antibodies, from which the antiserum is extracted. The antibody mix is then purified.
This means that the supply of your exact antibody mix is finite, determined by the lifetime of the animal used for production. Therefore, when producing a new batch, antibody characteristics can be different, having knock-on consequences for reproducibility.
This production method is, however, quick. This means it is more affordable to produce antibodies against less common targets, and they may be brought to market first.
How can polyclonal antibodies be used?
If you have variations in your epitope or a very small sample size, a polyclonal antibody may stand a better chance of quickly detecting your target than a monoclonal antibody.
Given this, they are often thought of as a good choice for applications such as IP and ChIP. It is worth nothing that suppliers we talk to do not always believe this is true based on their experience of raising monoclonal and recombinant antibodies for these specific applications.
There are over 4.5 million polyclonal antibodies on CiteAb; you can use our antibody search engine to find the right one for your application and target.
Reproducibility considerations for polyclonals
It is important to bear in mind the batch to batch variability with polyclonal antibodies, which can have an impact on the reproducibility of your work. It is crucial to validate each batch to ensure that the antibodies are specific to your target.
You can read our introductory guide on antibody validation here.
Interestingly, we have been seeing a slight decrease in the use of polyclonals over the past decade – this may be a reflection of these limitations.
What are monoclonal antibodies?
Monoclonal antibodies are produced by a single clone of a B cell, meaning that they target a single epitope.
How are monoclonal antibodies produced and what are their advantages?
Monoclonals are produced by immunising a host animal, such as a mouse, rabbit, rodent or alpaca, and extracting the antibodies against the intended target. [1]
Following this, the pool of antibodies are purified to leave you with one clone. The clone is fused to myeloma cells to produce hybridoma cells and immortalise production.
Because of this, these antibodies show less batch to batch variability. Unfortunately, this is an expensive and time consuming process. [2]
How can monoclonal antibodies be used?
As a research reagent, monoclonal antibodies can be used across many applications, such as: WB, iP, IF, ChIP, ELISA, FC and more.
But how to decide when to use a monoclonal antibody? If there is a well used and validated monoclonal antibody against your target, they offers the advantage of greater reproducibility over a polyclonal alternative. One approach could be to test recombinant, mono and polyclonal antibodies alongside each other to choose the best option.
Interestingly, monoclonals are increasing in popularity, overtaking polyclonals by citation share in 2016. You can search over 1.8m monoclonal antibodies on our antibody search tool.
Reproducibility considerations for monoclonals
It is important that monoclonal antibodies you use are properly validated; meaning that they are specific to your target, and work in your application as intended.
Because monoclonal antibodies are produced by a single clone they have more consistency between batches than polyclonals. This can give greater confidence they will give you reproducible results.
It is worth bearing in mind, however, that the hybridoma method can result in genetic drift over time. This can have knock-on implications for the specificity of your antibody and result in some variability. On top of this, there have been studies showing that within individual hybridomas there can still be antibody diversity. [3]
What are recombinant antibodies?
Recombinant antibodies are produced from an antibody coding sequence, showing specificity against a single epitope.
How are recombinant antibodies produced and what are their advantages?
Recombinant antibodies are produced by sequencing an antibody, cloning the sequence into vectors, and then expressing it recombinantly in hosts such as mammalian cells, which can help to give the right post translational modifications. [4]
How does recombinant production compare with hybridoma methods? Recombinant methods are more consistent in supply and stability in the product generated, with no susceptibility to genetic drift.
The other advantage of recombinant antibodies is that they can be engineered to improve performance, through methods such as class switching.
It is worth noting that many suppliers are moving towards producing more recombinants, and research use for these products is increasing!
How can recombinant antibodies be used?
Recombinant antibodies can be used across a variety of applications: western blot, immunohistochemistry and immunocytochemistry to name just a few.
Although they target a single epitope. It is worth noting that new recombinant products have come to the market which combine the advantages of both polyclonals and monoclonals. To achieve this, a chosen mix of monoclonal recombinant antibodies is produced. [5]
We have over 250k recombinant antibodies on the CiteAb antibody search engine that you can browse and evaluate.
Reproducibility considerations for recombinant antibodies
Due to the way they are produced, recombinant antibodies achieve high batch-to-batch consistency. This means that they can help support reproducibility in your research. [6]
This is not to say that antibody validation isn’t still an important step, and we always recommend validating your antibody in your exact experimental setup! A recombinant might have low variability but still cross react with proteins other than its intended target, misleading your research.
Start your search now:
Now that you are clearer on the differences between the key types of antibodies, why not browse for one for your experiment in our antibody search engine?
Other antibody resources to check out
Wrap-up
We hope you enjoyed getting to know the different types of antibodies a little better in this blog post!
Be sure to check out our other introductory science guides on our blog, and sign up to our newsletter to be kept up to date with our latest search engine news and science guides.
- Skye and the CiteAb team
References:
1.Bradbury, A. and Plückthun, A. (2015). Reproducibility: Standardize antibodies used in research. Nature, 518(7537), pp.27–29. doi:https://doi.org/10.1038/518027a.
2. Sumner, C. (n.d.). What makes an antibody monoclonal, polyclonal, or recombinant? [online] blog.cellsignal.com. Available at: https://blog.cellsignal.com/what-makes-an-antibody-monoclonal-polyclonal-or-recombinant [Accessed 15 May 2024].
3. Lipman, N.S., Jackson, L.R., Trudel, L.J. and Weis-Garcia, F. (2005). Monoclonal Versus Polyclonal Antibodies: Distinguishing Characteristics, Applications, and Information Resources. ILAR Journal, [online] 46(3), pp.258–268. doi:https://doi.org/10.1093/ilar.46.3.258.
4. Bradbury, A.R.M. et al. (2018) ‘When monoclonal antibodies are not monospecific: Hybridomas frequently express additional functional variable regions’, mAbs, 10(4), pp. 539–546. Available at: https://doi.org/10.1080/19420862.2018.1445456.
5. GEN – Genetic Engineering and Biotechnology News. (2022). Spoilt for Choice: Polyclonal, Monoclonal, or Recombinant Antibodies. [online] Available at: https://www.genengnews.com/resources/spoilt-for-choice-polyclonal-monoclonal-or-recombinant-antibodies/ [Accessed 15 May 2024].
6. Ferrara, F., D’Angelo, S., Gaiotto, T., Naranjo, L., Tian, H., Gräslund, S., Dobrovetsky, E., Hraber, P., Lund-Johansen, F., Saragozza, S., Sblattero, D., Kiss, C. and Bradbury, A.R. (2014). Recombinant renewable polyclonal antibodies. mAbs, [online] 7(1), pp.32–41. doi:https://doi.org/10.4161/19420862.2015.989047.