Expression of a shark antibody using Trichoderma reesei as a heterologous host

The increasing demand on the manufacture of therapeutic proteins has led to the use of microbial expression systems for the heterologous production of the desired protein. The filamentous fungus Trichoderma reesei has been proven to be a powerful expression system for the production of various heterologous proteins and their secretion to the culture medium (Nevalainen et al., 2005). In this study, we have used a low protease strain of T. reesei for the production of a shark antibody fragment variable region (V-NAR) of an antibody molecule called I(g)NAR (Immunoglobulin new antigen receptor) from the Wobbegong shark (Orectolobus maculatus). These single antibody variable domains are used as binding proteins and possess a number of applications in human medicine due to their relatively small structure and stability (Nuttall et al., 2002, 2003).