Selection and design in antibody phage display

Abstract: The immune system is an important part of the physiology of higher organisms. In the immune system antibodies play a key role in neutralizing and clearing potentially lethal threats from the environment. The importance of antibodies in the immune system has made them come to the attention as a tool in chemistry and medicine. This thesis, which is based on four original papers, deal with antibody development using phage display libraries. In the articles in this thesis efforts have been made to develop antibodies with the ability to distinguish between healthy cells and tumor cells with potential applications in diagnosis, prognosis and therapeutics. We have also made efforts in streamlining the process of extracting such antibodies from in vitro display libraries. In the first three papers, questions regarding antigenicity, antigen design, affinity maturation and specificity fine-tuning are highlighted and the importance of design of antibody libraries, antigens and methods of separation are key features of this thesis. Based on the first two papers in this thesis I conclude that using a simplistic design of the antigen may lead to an unsuccessful panning process of the chosen antibody library that when panned with a more efficiently designed antigen was found to contain antibodies of the desired specificity. This chain of issues leads to the development of several antibodies with differential recognition of and binding to the tumor-associated antigen MUC1. I conclude that these antibodies would be suitable candidates for use in cancer diagnosis and also have the possibility to be used in treatment. There is a great demand for affinity binders in proteomics and several efforts are in play to meet the demands for binders towards all constituents of the human proteome. We meet this demand in the fourth paper by developing a system for automatic wash and separation for use in high-throughput selections. This system is suitable of extraction of binders from phage display libraries against large numbers of targets.