Protein-Antibody Conjugation (PAC)

As a leading service provider in drug discovery, BOC Sciences offers a comprehensive range of bioconjugation services for a variety of drug conjugates, including alternative vectors, payloads, and linkers. We provide protein-antibody conjugation services to meet your unique project needs.

What is Protein Antibody Conjugation?

Protein-antibody conjugation is the process of linking or attaching a protein to an antibody. Common strategies for protein-antibody conjugation include chemical cross-linking, biological conjugation, and genetic engineering methods.

1. Bioconjugation methods: Bioconjugation methods utilize specific reactions between functional groups, such as click chemistry, avidin-biotin interactions, or enzyme-mediated reaction. These methods allow precise control of the splicing process and are highly specific and efficient.

2. Chemical cross-linking methods: Chemical cross-linking involves the use of reactive chemical groups, such as maleimides, NHS esters, or aldehydes, which can react with specific amino acid residues (e.g., cysteines or lysines) on the antibody or target protein.

3. Genetic engineering methods: Genetic engineering methods produce recombinant proteins that combine the properties of two molecules by fusing a gene encoding a target protein with a gene encoding an antibody.

Protein-antibody conjugates can be used in a variety of fields, including targeted drug delivery, immunotherapy, imaging, and diagnostics.

Fig.1 Site-specific conjugation of antibody and protein. (Park, 2021)

Protein Antibody Conjugation Service

BOC Sciences performs protein-antibody conjugation development. The conjugates can then be combined and modified based on the different antibodies and proteins we have available.

• Protein-Antibody Conjugate Design
  When designing protein-antibody conjugates, it is necessary to consider the characteristics of the antibody and protein carrier, the needs of the target application, and the feasibility and effectiveness of the coupling method.
  Similar to ADCs, proteins can simply be used as fusion proteins to bind to antibodies, but this approach may have the limitation of a low drug-to-antibody ratio. Since both the targeting antibody and the protein cargo are large hydrophilic proteins, the assembly sites need to be precisely designed. The antibody can be used to decorate the surface of the nanoparticle, while the cargo protein is coated be present on the inside so that it cannot be accessed by degrading proteases. Covalent attachment of antibodies or proteins to nanoparticles can be carried out during the construction of the PAC using bioorthogonal reactions.

  Item	Types
  Protein	Protein A Protein G Protein L Green Fluorescent Protein (GFP) Red fluorescent protein (RFP) His-tag binding protein
  Antibody	IgG class (including subclasses IgG1, IgG2, IgG3, IgG4, etc.) IgM class antibodies IgA class antibodies IgE class antibodies IgD Antibodies

  
  BOC Sciences offers various combinations of the proteins and antibodies. Our experts will analyze your project, evaluate the binding possibilities and design a reliable solution that is guaranteed to meet your requirements.

• Protein and Antibody Modification
  Reactive group introduction - Introduction of reactive groups, such as amino, carboxyl, and thiol groups, on the surface of proteins to allow for chemical reactions with other molecules.
  Chemical cross-linking - Antibodies can be cross-linked to proteins by chemical cross-linking agents.
  Targeted genetic engineering - Through genetic engineering techniques, amino acid residues are inserted at specific positions in the antibody to provide specific modification sites, such as tags (e.g., His tags, FLAG tags) or specific functional groups.

• Protein-Antibody Conjugate Assay
• BCA/Lowry/Bradford Protein Concentration Assay
• ELISA (enzyme-linked immunosorbent assay)
• Western blot