AgX – Antigen Expression Services
Need an antibody, but don’t have a purified protein antigen?
Try AgX Antigen Expression Service –
and have your antigen in 3 weeks!
AgX provides rapid high-level bacterial expression and purification of protein antigen domains from cDNA or PCR products. These protein domains (100aa to 300 aa) are ideal for generation of highly specific monoclonal antibodies from the HuCAL antibody library, and add just 3 weeks to the 8 week antibody generation process.

Trying to express your antigen? AgX saves you time and effort
If you are having trouble expressing or purifying the full length protein antigen, our AgX service is the ideal solution. We will work with you to determine which regions of the protein are of most interest and use advanced bioinformatics tools to find the best sequences for expression and antigenicity.
- Antibodies to short domains are ideal for expression analysis of genes with an unknown full-length sequence and/or unknown function.
- HuCAL antibodies against AgX antigen domains have been successful in various immunoassays against proteins from several species (e.g. human, mouse, rat, virus, microorganisms) and of different function and localization (e.g., receptors, integrins, hormons, transcription-factors) (Fig. 1)
Figure 1. IHC using antibodies against AgX antigen domains

- Murine eyes: formalin-fixed, paraffin-embedded

- Murine Intestine: formalin-fixed, paraffin-embedded
Thinking about using a peptide antigen? AgX is the way to better antibodies
When there is no purified protein antigen available, researchers often turn to peptides as antigens. This is unfortunately not always the best choice.
- Expressed domains from AgX (100 to 300 amino acids) are typically longer than peptides (10 to 25 amino acids) and thus provide more epitopes for antibody generation.
- An N1-fusion partner facilitates expression in E.coli and refolding of the target protein sequence
- Fragments larger than 100 amino acids generally fold into a rigid structure and are more likely to have 3-D epitopes present in the parental protein.
- Antibodies to protein domains generally show higher affinities than antibodies generated using peptide antigens.
Start with just 1 microgram of cDNA or PCR-fragment
We use advanced bioinformatic tools and work closely with clients to determine the ideal domain for optimal cloning, expression, and purification. The chosen sequence is then cloned into our proprietary expression vector and verified by DNA sequencing. The protein domain is then expressed, purified, and refolded ready for use as an antigen. Unused antigen (100 µg) is shipped to the client along with the purified antibodies approximately 8 weeks after the start of panning. Additional antigen can be shipped within two weeks after re-order!
No cDNA? AgX is still the best way to create your antigen!
Even if only protein or DNA sequence information is available, there are still excellent alternatives to peptides as antigens. We are happy to arrange for clone purchase (where available), gene synthesis of the selected domain, or cloning of the gene from an existing library.
If you need an antibody, but don’t have the antigen ready, contact us today to see how AgX Antigen Expression Service and HuCAL Custom Antibody Generation can speed up your research. Simply complete a simple AgX Inquiry Form on-line, and one of our technical experts will contact you as soon as possible to discuss your needs and see how we can help.
Read more about the technology:
- J Immunol Methods. 2003 Apr 1;275(1-2):203–12.
From EST to IHC: human antibody pipeline for target research. - Genomics. 2003 Aug;82(2):130–42.
Kirrel2, a novel immunoglobulin superfamily gene expressed primarily in beta cells of the pancreatic islets.
