title: The in vitro antitumor effect and in vivo tumor-specificity distribution of human-mouse chimeric antibody against transferrin receptor.
abstract: Transferrin receptor (TfR/CD71) deserves attention as a selective target for cancer therapy due to its higher expression in tumors versus normal tissues. Also, it has been shown the mouse-derived monoclonal antibody against TfR can significantly inhibit the proliferation of tumor cells. Through constructing the chimeric antibody against TfR, the antigenicity of antibody can be weakened, and most importantly, the antitumor effect of antibody can be strengthened by the introduction of the human Fc fragment. In previous studies, we successfully constructed the human-mouse chimeric antibody against TfR (D2C) and demonstrated that its Fab fragment could specially recognize the TfR on the surface of target cells. In this study, through labeling the chimeric antibody D2C with 125I, we calculated the affinity constant (Ka) of 9.34-9.62x10(9) l/mol for this antibody according to the Scatchard drawing method. Moreover, in vivo studies in nude mice-bearing human liver cancer (SMMC-7721) xenografts have shown that the radioactivity distribution ratio of 131I-D2C on T/NT was 2-14:1 or 3-21:1 on the seventh day after intraperitoneal or intratumoral injection of 131I-labeled D2C (131I-D2C). These evidences indicated that the in vivo distribution of D2C display the characteristics of certain tumor-specificity localization. In vitro studies, D2C can induce the apoptosis of K562 through the mitochondria death pathway and arrest the cell at G1 phase, as determined by cell cycle analysis. Using the human tumor cells (K562, CEM, and SMMC-7721) expressing TfR as target cells, and normal human PBMC as effector cells, Fc fragment of D2C can perform both the antibody-dependent cell-mediated cytotoxicity and the complement-dependent cytotoxicity. Together, it was demonstrated that the D2C display a tumor-specificity distribution, and has a strong antitumor effect. Thus, it has the potential therapeutic significance.
authors.affiliation: Laboratory of Molecular and Immuno-Pharmacology, Department of Pharmacology and Immunology, Tongji Medical College, Huazhong University of Science and Technology, No. 13, Hongkong Road, 430030 Wuhan, People's Republic of China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Qing
authors.forename: Wang
authors.initials: W
authors.lastname: Shuo
authors.forename: Wang
authors.initials: W
authors.lastname: Zhihua
authors.forename: Zhu
authors.initials: Z
authors.lastname: Huifen
authors.forename: Lei
authors.initials: L
authors.lastname: Ping
authors.forename: Liu
authors.initials: L
authors.lastname: Lijiang
authors.forename: Zhao
authors.initials: Z
authors.lastname: Xiaorong
authors.forename: Chao
authors.initials: C
authors.lastname: Liming
authors.forename: Xiao
authors.initials: X
authors.lastname: Daiwen
authors.forename: Huang
authors.initials: H
authors.lastname: Yu
authors.forename: Xing
authors.initials: X
authors.lastname: Wei
authors.forename: Fang
authors.initials: F
authors.lastname: Min
authors.forename: Feng
authors.initials: F
authors.lastname: Zuohua
authors.forename: Shen
authors.initials: S
authors.lastname: Guanxin
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000494:pharmacology*; D015703:Antigens, CD / Q000276:immunology*; D000970:Antineoplastic Agents / Q000494:pharmacology; D017209:Apoptosis; D001666:Binding Sites, Antibody; D001667:Binding, Competitive; D053181:Caspase 8; D020169:Caspases / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000378:metabolism; D045744:Cell Line, Tumor; D002470:Cell Survival; D045304:Cytochromes c / Q000378:metabolism; D004354:Drug Screening Assays, Antitumor; D005434:Flow Cytometry; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000494:pharmacology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009369:Neoplasms / Q000188:drug therapy* / Q000276:immunology / Q000378:metabolism; D011990:Receptors, Transferrin / Q000276:immunology*; D011993:Recombinant Fusion Proteins / Q000493:pharmacokinetics / Q000494:pharmacology*
chemical_list: D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D000970:Antineoplastic Agents; C068126:CD71 antigen; D018797:Cell Cycle Proteins; D007140:Immunoglobulin Fab Fragments; D011990:Receptors, Transferrin; D011993:Recombinant Fusion Proteins; D045304:Cytochromes c; C505530:CASP8 protein, human; C505526:Casp8 protein, mouse; D053181:Caspase 8; D020169:Caspases