Once upon a time, my friend told me she ever experienced antibody sequencing and I was surprised because I didn’t think it’s a good way. However, what’s surprising is that I am participated in antibody development now. And I know it’s necessary to conduct antibody sequencing for it helps us know the body better. Nowadays, humanized antibody has attracted increasing attention around the whole society. So, what is it?
Generally speaking, humanized antibody mainly refers to the murine monoclonal antibody with gene cloning and DNA recombinant technology. And most of the amino acid sequences are replaced by humanized sequences, which substantially retain the affinity and specificity of parent murine monoclonal antibody. At the same time, it also reduces the heterogeneity to a large degree which is beneficial to its application in human beings. Clearly, humanized antibody can greatly reduce immune side effects in human organisms that caused by heterologous antibody. In fact, humanized antibody might be divided into several categories. A brief analysis is as followed.
Chimeric Antibody
Based on DNA recombinant technology, it can insert variable region gene of heavy chain into the expression vector that contains human antibody’s constant region and then transform mammalian cells for expressing a chimeric antibody. In this way, heterogeneity is existed in antibody molecules, as well as the humanized. Such antibody can reduce the immunogenicity of heterologous antibody while at the same time retain parent antibody’s ability in connecting antigen.
Modified Antibody (CDR Grafting Antibody)
Generally, CDR in antibody variable region can be regarded as the region that connects antibody recognition and binding antigen together, which will directly decide antibody’s specificity. Whereas, although the main antigen is always contacted with CDR in antibody, FR region can participate in the activity as well because it might lay an effect on the spatial configuration of CDR. Thus, if properly configured, the affinity of modified antibody can be equivalent to that of original murine antibody. Humanized antibody cannot realize the goal for its own shortcomings.
Fully Humanized Antibody
It mainly refers to the the technology that can fully transfer human encoded genes to those animals without antibody gene, utilizing transgenic and transchromosomal technology. Under such condition, those animals can express human antibody, trying to realize the purpose of fully humanized antibody to a better degree.
Considering its real state, humanized antibody will embrace a brighter future under the support of various modern biological technologies.