Antibody Variable Region Sequencing

The part of the antibody that can undergo changes is known as the V region, or variable region. The variable region includes the terminal parts of the light and heavy chains. The antibody can uniquely recognize a specific feature of a foreign substance through its variable region, and this foreign target is called an antigen. Sequencing the antibody variable region aids in the functional study of antibodies. Biopike Biotech offers mass spectrometry-based antibody variable region sequencing services.

Antibody variable region

The antibody variable region refers to the region in the heavy and light chains of an antibody where the amino acid sequence and composition vary greatly. This region is near the N-terminal of the antibody peptide chains. The antibody variable region is further divided into hypervariable regions and framework regions. The hypervariable region is where the amino acid sequence and composition are highly variable, with three hypervariable regions in each heavy and light chain. Together, these hypervariable regions form the antigen recognition and binding site of the antibody, determining the antibody's specificity and forming epitopes complementary to antigenic determinants, thus also known as complementarity-determining regions (CDRs). The framework region is the relatively stable part of the amino acid composition and sequence outside the hypervariable regions of the antibody variable region.

Antibody variable region sequencing

Antibody variable region sequencing helps in the functional study of antibodies or verifying the correctness of antibody function. There are various methods for sequencing the antibody variable region, such as Edman degradation, mass spectrometry, or deducing the sequence by determining the gene sequence of the antibody. The sequence derived from the gene sequence is a theoretical value of the antibody amino acid sequence. To know the actual amino acid sequence of the antibody variable region, direct amino acid sequence analysis of the antibody variable region is required. Edman degradation can sequence about 50 amino acid residues at the N-terminal of the antibody, but it cannot sequence antibodies with a blocked N-terminal. Mass spectrometry sequencing can cover the entire region of the antibody variable region and can also sequence antibodies with a blocked N-terminal.

Related services

Mass spectrometry-based sequence analysis
N-terminal protein sequencing based on Edman degradation
Monoclonal antibody sequencing service based on PCR amplification
De novo sequencing