Antibodies are useful molecules for research, diagnosis, treatment, etc., including molecular-targeted drugs.However, since it is obtained mainly by administering an antigen to an animal, it takes a lot of time and cost, and it is also a problem from the viewpoint of animal welfare.

　On the other hand, in recent years, "Nanobody", which has the same characteristics as conventional antibodies but has a molecular weight of about 10/1, has been attracting attention.Nanobodies are antibodies consisting only of the antigenic determination sites of single-chain antibodies possessed by camelids.
In this study, which aimed to produce antibodies without using animals and to establish a screening method, it is said that monoclonal antibodies were produced using yeast based on this Nanobody.

　First, a free Nanobody was prepared by yeast, and a new label called peptide barcode was added to create a barcode antibody.As a model, different peptide barcodes were added to the anti-CD4 Nanobody and anti-GFP Nanobody.Next, the anti-CD4 Nanobody and anti-GFP Nanobody were reacted with CD4 on the beads on which CD4 was immobilized.After washing and removing the unbound Nanobody, the peptide barcode was cut out and quantified by mass spectrometry. As a result, only the peptide barcode of the anti-CD4 Nanobody having the binding activity was detected.In other words, by using peptide barcodes, it is possible to evaluate the binding ability of multiple antibodies.

　This system, which can rapidly generate Nanobodies in vitro and adjust monoclonal antibodies by screening, will be used for various purposes such as drug discovery such as molecular target drugs (antibodies) and molecular probes for intracellular imaging. It is expected.

Paper information:[PLOS ONE] Peptide barcoding for establishment of new types of genotype–phenotype linkage