| ||Monoclonal antibodies are usually produced using mouse B cells which limits their use in the treatment of human disease. Often, a patient's immune system will recognise the mAbs as foreign and mount an attack. The mAbs will be rapidly inactivated and there may be accompanying flu-like symptoms, allergic reactions and in extreme cases, systemic shock , or death. Recently, Dr Greg Winter and a team of scientists at the MRC Laboratory of Molecular Biology (MRC-LMB) in Cambridge have overcome this problem by 'humanising' mAbs. The small antigen-binding region from the mouse antibody (red in Figure 2) is transferred by genetic engineering to an otherwise human antibody. The resulting 'hybrid' antibody molecule is effective against its antigen but is less likely to provoke an immune response.
This humanising procedure still depends upon initial immunisation of mice and the complexities of the immune response. In an alternative strategy, MRC scientists at the LMB have collaborated with others to create transgenic mice with human antibody genes instead of mouse ones, enabling the production of 100% pure human mAbs.