| During the past thirty years, thousands of murine monoclonal antibodies havebeen made and some of them can be used therapeutically. However, the propertyof provoking strong Human anti-Murine Antibody (HAMA) immune responsesrestricts their application clinically. For reducing the immune responses of murineantibodies, human-rat chimeric antibody was maded by gene engineering.Although the immunogenicity of human-rat chimeric antibodies is reduced,Human anti-Murine Antibody reactions are still produced. For reducing the murinecomponent of antibody further, people build the hominine antibody. The CDR ofmurine antibody is put into the corresponding position of hominine antibody CDR,so the antibodies only keep the CDR of murine antibody, These hominineantibodies make their application as medicine in clinic come true.Phage antibody library technique is the associative product of combinativetechnique and gene engineering technique, is a hotspot in antibody engineering. Itmakes people can simulate the whole process of antibodies production in vitro, itsupply a simple and highly effective operation system, thus it has importanttheoretic signification and application foreground.We used the framework of fully synthesized antibody library published inliteratures. Through the analysis and calculation of human antibody CDR, humanantibody genes are devided into heavy chain group ( 7 subgroups), Kappa chain( 4 subgroups), Lamda chain ( 3 subgroups). 49 single chain antibody libraries,which is assembled by heavy and light chains, contain more than 95% of humanantibody gene. In the CDR section,in which diversity is the most high, therandomization design of amino acid was made according to statistic. Usingoriginal DNA grouping synthesis tactic, we make coding amino acids appearaccording to preconcerted kinds and frequency, realize limited randomizationeffectually. This way can completely overcome the abuse of simple degeneracysynthesization, on the foundation of "TRIM" synthetical method excellence, costcontrol and technic feasibility are advanced maximum, at the same time sequencewarp which is induced by compete ability difference with 20 TRIM in solid phasesynthesization can be avoided, and used to build other gene engineering library.Basic library capacity, redundancy , full degree of sequence and other libraryindex can be controlled by using DNA combination solid phase synthesis,extending measure without primer and et al. This library can be used to select scFvwith any antigen. The design of this antibody library is logical, the key technic forbuilding library is new and availability, it can be explanted, selection time is short,cost is less, and without immunogenicity,it have more value in the diagnosis andtreatment of paroxysmal infective disease.Bispecific antibody (BsAb) is at the very important position in tumour immunetreatment field . Single chain bispecific antibody (scBsAb) is a BsAb which havegood developmental foreground. One end of BsAb point to tumour correlativeantigen, the other end point to triggering molecμle of T cell, BsAb simμlate T cellactivation aroused by antigen transfer cells in physiology,also make the active Tcell point to tumour cell, make directional killing for tumour cell come true. CD3is expressed on the surface of all mature T cells, it forms TCR-CD3 complex withTCR, they take part in immune responsion together, they are the successful appliedtriggering molecμle in the building BsAb. CD3-based BsAb have huge appliedpotential in tumour treatment. BsAb in this article is scBsAb builded withanti-CD3 reshaping scFv and anti-human ovary cancer correlative antigenOC183B2 scFv. We use K3H3 which appeared most frequently in the fullysynthetic human combinatorial antibody library for primary library, take thescBsAb build by our lab for fixed antigen, do two selection, get high appetencyantibody . The protein was expressed in E.coli and purified, the other biologyactivities are need to be reseaeched...
|
PDF Full Text Request