Humanized antibodies are derived from non-human species, modified to more closely resemble existing, natural human antibodies. Their applications have a great deal of potential in medicine and immunology due to the wide range of variability that humanized antibodies provide. Compared with heterologous antibodies, they also circumvent certain immune side effects to the human body. From chimeric antibodies to CDR-grafting to humanized antibodies, each major breakthrough has helped expand the field of antibody preparation and advance the cutting edge of
antibody library technology .
The development of therapeutic antibodies has been tending toward the use of fully humanized antibodies, which are typically derived from antibody libraries. The development of antibody library technology makes it possible to more easily obtain antibodies in vitro. Antibody fragments can be immobilized on the surface of certain mediums, and specific antibody fragments can be obtained by multiple rounds of exposure to a certain antigen, followed by elution and signal amplification. Due to the competitive binding screening mechanism, antibodies with a high-copy number will be preferentially screened out from the library. After 1-2 rounds of screening, high-affinity and low-copy antibodies can then be screened by antibody library sequencing.
The classical antibody library displays phage coat protein III and VIII protein fusion scFv (single-chain variable fragment) on the surface of phage. Fully humanized scFv can be screened out by several rounds of antigen screening. There is now an improved way to screen for scFv completely in vitro, starting from the scFv antibody library. No terminator is inserted during in vitro transcription, following which a RNA-ribosome-scFv complex is formed. The complex which specifically combines to the target molecule can be obtained by a screening method similar to phage display. Finally, the RNA of the complex is separated and PCR amplification follows. The introduction of mutations along with the PCR amplification could stimulate the affinity maturation process and could be one option to amplify the affinity of the secondary antibody library.
Synbio Technologies provides antibody library sequencing services. Combining with our next generation sequencing technology, we offer a complete assessment of immune system diversity and comprehensive observation and analysis of T cells and B cells. These technologies and services. Our services are widely applicable to topics such as disease surveillance, antibody production, vaccine research, medicine, and immunology.
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