Based on AvantGen’s large natural human antibody database, AvantGen has designed human antibody libraries with multiple germline variable regions and included only those residues observed at the corresponding CDR positions of natural human antibodies derived from that same germline variable region to generate diversity while minimizing the number of antibody clones that are not favorable for downstream development. Large human antibody libraries (Germliner™) with more than 100 billion antibody clones displayed by AvantGen’s novel yeast display system have been constructed with frameworks from several human heavy (VH) and light chain (Vκ/λ) variable region germline genes. These libraries have been screened against more than 100 antigens, and panels of high affinity antibodies have been successfully isolated for each of these antigens. New antibody libraries with different germline frameworks are continuously being constructed to expand antibody repertories and epitope coverage.
To ensure the highest developability of antibodies isolated from our human antibody library, the following quality features are included in AvantGen’s Human Germliner Antibody Libraries:
- Fully human antibody germline frameworks are selected from human antibodies with favorable thermo-stability and solubility
- Post-translational modification (PTM) sites, such as glycosylation, deamidation, isomerization, oxidation and cleavage sites, are avoided in CDR1 and 2 sequences to increase the levels of homogeneity of the antibodies in production
- Amino acid residues that may form PTM sites are either excluded or reduced in CDR-H3 sequences compared to their natural occurrence in human antibodies in order to minimize post-translational modifications
- All other residues are incorporated into the libraries based on each amino acid’s frequency used by natural human antibodies at each CDR position for that given variable region family.