Construction And Expression Of Human-Mouse Chimeric Antibody Against Human CD40 And Characterization Of Its Biological Function

CD40 is a Mr 50,000 transmembrane protein in the tumor necrosis factor (TNF) receptor superfamily. CD40-CD40 ligand (CD40L) interactions play a critical role in the regulation of humoral and cellular immune responses. CD40 is expressed on B-cell malignancies, including human multiple myeloma (MM) and a variety of carcinomas. In cancers, mAbs and mAb-based reagents have shown clinical efficacy, the mAbs targeting CD40 on patient tumor cells represent an attractive therapeutic strategy for MM, and a variety of carcinomas also highly express CD40, broadening its potential therapeutic application.The murine antibody being unable to mediate complement-dependent cytotoxicity or antibody-dependent cellular cytotoxicity with human effector cells and in addition with HAMA preclude long term use of the murine antibody in patients. To increase the effector function and reduce immunogenicity of murine antibodies, DNA technology can be applied to construct chimeric antibodies. Such antibodies combine the V region of a mouse antibody with a human antibody C region, thus retaining the binding specificity of the murine antibody while presenting less foreign amino acid sequence to the human immune system.In this paper, basing on an agnostic CD40 monoclonal antibody (5C11) established by Dr Zhou of our laboratory, we constructed and expressed a human-mouse chimeric antibody against human CD40 in CHO cell, and characterized its biological effects on B cell lymphomas Daudi cell, which could provide clinic application substance of cross-linking of CD40 signal.In the part I, total RNA was extracted from the murine hybridoma cell line (5C11)...