Developing Recombinant Antibodies by Phage Display Against Infectious Diseases and Toxins for Diagnostics and Therapy

Abstract

Antibodies are essential molecules for diagnosis and treatment of diseases caused by pathogens and their toxins. Antibodies were integrated in our medical repertoire against infectious diseases more than hundred years ago by using animal sera to treat tetanus and diphtheria. In these days, most developed therapeutic antibodies target cancer or autoimmune diseases. The COVID-19 pandemic was a reminder about the importance of antibodies for therapy against infectious diseases. While monoclonal antibodies could be generated by hybridoma technology since the 70ies of the former century, nowadays antibody phage display, among other display technologies, is robustly established to discover new human monoclonal antibodies. Phage display is an in vitro technology which confers the potential for generating antibodies from universal libraries against any conceivable molecule of sufficient size and omits the limitations of the immune systems. If convalescent patients or immunized/infected animals are available, it is possible to construct immune phage display libraries to select in vivo affinity-matured antibodies. A further advantage is the availability of the DNA sequence encoding the phage displayed antibody fragment, which is packaged in the phage particles. Therefore, the selected antibody fragments can be rapidly further engineered in any needed antibody format according to the requirements of the final application. In this review, we present an overview of phage display derived recombinant antibodies against bacterial, viral and eukaryotic pathogens, as well as microbial toxins, intended for diagnostic and therapeutic applications.

Keywords: VHH antibodies; infectious disease; phage display; recombinant antibodies; scFv antibodies.

Figure 1

Schematic illustration of the antibody generation process. For the antibody generation, human phage display libraries or libraries from other species are used. These libraries will be used for the in vitro selection (panning) on a target molecule. In short: the antibody phage particles will be incubated with target molecule (in the illustration, a target molecule was immobilized in a microtitre plate well and a scFv phage display library is used), the non and weak binding antibody phage particles will be washed away and the binding antibody phage will be eluted (the procedure will be repeated 3-5 times) and further analyzed. In the next step, monoclonal binders will be identified, e.g. by ELISA. Finally, the selected antibody fragments can be recloned, because the corresponding gene is packaged in the phage particles, and produced in any antibody format tailored to the final application.