Estratégias para expressão de um anticorpo anti-CD3 humanizado em células de mamífero

AUTOR(ES)
DATA DE PUBLICAÇÃO

2009

RESUMO

The development of new pharmaceuticals derived from recombinant antibodies had a significant impact in the treatment of various illnesses. However, due to the structural complexity of the immunoglobulin molecule, the production of these molecules in mammal cells is still challenging. One of the difficulties is the equimolar production of heavy and light chains and the prevention of the stress induced by the accumulation of unassembled protein. We are working with a potentially immunoregulatory recombinant humanized antibody specific for the human CD3 antigen. Anti-CD3 antibodioes have been used in the prevention of the acute graft rejection and are considered as a promising pharmaceutical for the treatment of autoimmune diseases. The production of this antibody in culture of animal cells has shown to be problematic due to the low yield of recombinant antibody recovery. In the attempt to create alternative strategies for recombinant production of antibody, monocistronic, bicistronic and tricistronic expression vectors were constructed to coordinate the expression of a complete antibody in mammal cells. The monocistronic versions possess a furin cleavage coding sequence between the both antibody chains. The bicistronic version possesses a synthetic IRES element between the two chains. A selective mark for the Geneticin antibiotic was introduced in the expression cassette as an extra cistron driven by another IRES element. The cell lines HEK293 and BHK-21 were used for transient or stable production of the anti- CD3 antibody. Recombinant antibodies were purified by affinity chromatography and analyzed for the production of intact immuglobulin. The results indicate that the bicistronic construction pMACIA HIL and the monocistronic construction pMACIA HL are capable to express both antibody chains. On the other hand, the monocistronic construction pMACIA LH or the bicistronic construction pMACIA HL IRES neo were not able to produce the recombinant antibody. The tricistronic vector pMACIA HIL IRES neo was shown to be the most promising construction to obtain the whole antibody production in stable transfectomes.

ASSUNTO(S)

bicistronic anti-cd3 anticorpo antibody bicistrônica biologia molecular monocistrônicas monocistronics anti-cd3

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