AltaBioscience specialises in synthesising custom peptide antigens for use in antibody production and custom antibody generation. Synthetic peptides as immunogens have proven advantages over protein immunogens. By themselves, peptides are too small to elicit an immune response, so they must be presented as larger entities in order for the body to detect them and produce an antigenic response.
Our peptide antigen service offers two methods of peptide antigen production:
Suitable for both monoclonal antibody production and polyclonal antibody production, our peptide synthesis experts can assist with peptide antigen design using our epitope design software, thereby suggesting antigenic peptide regions likely to provide the best immune response.
For purification, we can supply our ready-to-use reusable affinity columns, designed by AltaBioscience. These columns have your peptide antigen immobilised on a solid support and are ready for polyclonal antibody purification.
Whether you select MAPS synthesis or peptide-protein carrier conjugations for your immunogen program, we can also provide unconjugated linear peptides for use in blocking assays.
Multi-antigenic peptides (MAPs) are an effective method of antibody production using synthetic peptides. Eight identical peptide chains are synthesised and covalently joined to a common polylysine core. The molecular weight of these peptides (10kDa-15kDa) is ideal for them to be highly immunogenic without the need to couple to a carrier protein.
This technique gives very high titres and works for any epitope. For the extreme C-terminus of a protein, we recommend our alternative method of peptide antigen via conjugation to a protein.
Image shows 8 branched maps (8 linear peptides on poly-lysine core)
With expertise spanning more than 45 years, our peptide chemists can assist with the design of peptide antigens. Using our software designed in-house, we look at both the antigenic potential of epitopes along the protein and also take into consideration the synthesis implications required for each specific peptide sequence identified. For selection, we aim to include flexible regions including both hydrophilic and hydrophobic amino acids, ensuring that a significant percentage of charged residues such as Lys, Arg, Glu and Asp can be incorporated, avoiding, where possible, any highly hydrophobic regions. Prolines, whilst favourable in the synthesis process, are not as helpful in peptide antigens as they produce a bend in the peptide backbone which alters shape. Cys-containing regions should also be avoided as these residues would generally be points of di-sulphide bridging in the protein.
Immunisation using two different peptides from one protein may increase the chance of successful antibody generation.
Our laboratory has developed the technology to make peptides covalently bound to controlled pore glass (Peptide – CPG) for use as affinity columns. This material has many advantages over other types of support: it has good flow rates and is mechanically and chemically very robust with almost an indefinite lifetime.
Whilst we provide purification as part of our polyclonal antibody production service, we can also provide protocols for using our affinity purification columns should you wish to purify your own serum.
These columns can be used to purify antibodies raised by MAPs or peptide-protein conjugation methods.
Our affinity columns can be used repeated times and offer a robust, ready-to-use product for antibody purification.
Peptide antigens are ideal for use in generating antibodies in both polyclonal and monoclonal antibody production services.
Peptides as antigens have several advantages over proteins when used as immunogens in antibody production. Native proteins may not be readily available or stable enough for use giving peptide antigen synthesis many advantages over protein antigens.
We offer free technical advice for selecting peptide antigens. Our team will not only consider the likely antigenicity of the epitope but also the implications regarding the peptide synthesis. Additionally, there are online antigen predictors such as Epitope Prediction and Analysis Tools – IEDB Analysis Resource
The following are general tips for epitope selection:
