Primary Expression Of Anti-CD22 Humanize Engineering Multivalent And Miniantibody

Rituxan, as the first chimeric antibody, was approved into market in 1997 by FDA. Although rituxan is effective and its toxicity can be controlled, even in those had showed positive effect group, recurrence presented.This situation inspirited scientists to screen new targets. CD22 on the surface of normal and cancer B cell. The therapy focused on CD22, neither affects its wxpression in tissue nor inhibits cytopoiesis of B cell.The therapy against NHL now includes RATx, ST, and biotherapy and so on. Immune targeted therapy plays an important role in lymphoma. Some researches indicated that multivalent and miniantibody can improve their affinity of B cell because antigen binding site increasing, so they considered that this kind of multivalent and miniantibody is more stable and suitable for Immune targeted therapy.The aims of the experiments are to obtain this multivalent and miniantibody and to get the expression strains, and characterise their activities.Firstly Fc-500,CH3-1300,Fc-1600 genes were amplified by PCR. After two expression plasmids contain fusion gene of Fc-500 and CH3-1300 or Fc-500 and Fc-1600 were constructed, and then were electrotransformed into Phicia pastoris GS115. The results showed that the recombinant strains GS115-CH3, GS115-Fc not only can express designed protein, but also are stable after 4 generations mutiplication.In another experiment, we tried to express in recombinant baculovirus. Expression plasmids were tranfected into Sf9. Recombinant baculovirus Sf9-CH3 which expressed the multivalent and miniantibody were also been screened. Virus titer was 4.5×10~7pfu/ml. The results indicate that we have got the recombinant virus can also express designed protein.