title: Chemically programmed bispecific antibodies that recruit and activate T cells.
abstract: Bispecific antibodies (biAbs) that mediate cytotoxicity by recruiting and activating endogenous immune cells are an emerging class of next-generation antibody therapeutics. Of particular interest are biAbs of relatively small size (∼50 kDa) that can redirect cytotoxic T cells through simultaneous binding of tumor cells. Here we describe a conceptually unique class of biAbs in which the tumor cell specificity of a humanized antibody fragment that recognizes CD3 on T cells is chemically programmed through a C-terminal selenocysteine (Sec) residue. We demonstrate that through chemically programmed specificity for integrin α(4)β(1) or folate receptor 1 (FOLR1), and common specificity for CD3, these hybrid molecules exert potent and specific in vitro and ex vivo cytotoxicity toward tumor cell lines and primary tumor cells in the presence of primary T cells. Importantly, the generic nature of chemical programming allows one to apply our approach to virtually any specificity, promising a broad utility of chemically programmed biAbs in cancer therapy.
authors: Experimental Transplantation and Immunology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA.
authors: Huiting
authors: H
authors: Cui
authors: Joshua D
authors: JD
authors: Thomas
authors: Terrence R
authors: TR
authors: Burke
authors: Christoph
authors: C
authors: Rader
mesh_terms: D018033:Antibodies, Bispecific / Q000235:genetics / Q000276:immunology* / Q000494:pharmacology; D000918:Antibody Specificity; D017252:CD3 Complex / Q000235:genetics / Q000276:immunology*; D058975:Folate Receptor 1 / Q000235:genetics / Q000276:immunology; D006367:HeLa Cells; D006801:Humans; D039041:Integrin alpha4beta1 / Q000235:genetics / Q000276:immunology; D019169:Jurkat Cells; D008213:Lymphocyte Activation; D009369:Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000276:immunology; D017279:Selenocysteine / Q000235:genetics / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D018033:Antibodies, Bispecific; D017252:CD3 Complex; C548696:FOLR1 protein, human; D058975:Folate Receptor 1; D039041:Integrin alpha4beta1; D017279:Selenocysteine