Biopharmaceuticals are therapeutic proteins produced using biotechnology. Monoclonal antibodies (mAb) are glycoproteins, which are also an important part of our immune system. They are the most common type of bipharmaceuticals currently in the market and are produced using recombinant DNA technology by Chinese Hamster Ovary (CHO) cells. During their synthesis, various post-translation modifications take place. One of the most important modifications is glycosylation, where glycal structures are added to mAb. These structures have a major impact on physical, chemical and effector functions of antibodies (Ab) such as: antibodies cell dependent citotoxicity (ADCC), low immunogenicity, complement dependent citotoxicity (CDC) and appropriate Ab half-life. Therefore, characterisation and quantification of glycans is of critical importance during developement and manufacture of therapeutic proteins. The main scope of our work was the development of a method for characterisation of glycan structures using specific proteins, called lectins. The primary analitical technique used was BLI (Bio-Layer Interferometry), which enables real-time measurements of molecular binding. We have developed a practical method for quantification of glycans in purified and denaturated samples as a major improvement over convetional expensive and time-consuming procedures.
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