ANTIBODY FRAGMENTS SPECIFIC IN RELATION TO HUMAN CANCER-EMBRYONIC ANTIGEN (CEA) Russian patent published in 2007 - IPC C07K16/18 C12N15/13 C12N15/63 A61K39/395 C12P21/08 G01N33/53 

FIELD: biotechnology, in particular tumor immunotherapy.

SUBSTANCE: invention relates to monovalent and divalent single-stranded (diantibody) Fv-fragments (scFv) of antibodies obtained by using of extracted RNA producing of hybridoma Mab CB/ior-CEA.1. Antibodies fragments according to the invention have predetermined amino acid sequence (such as defined in sequence list), are specific to human CEA, have CEA affinity constant of (5.0±0.4)x10^-9 l/mol for monovalent fragment and (2.8±0.3)x10^-10 l/mol for diantibody. Disclosed is application of abovementioned fragments in pharmaceutical compositions for treatment of human CEA-expressing tumors and determination of tumor localization in vivo. Described is modified cell expressing said antibody fragment, as well as multicellular genetically modified organism such as transgenic plant. ScFv fragments of monovalent antibody and diantibody have no Fc-domains and have smaller molecule size than mice Mab and as a result fragments are better penetrate in tissue in vivo and have less immunogenic action in living body.

EFFECT: antibody fragments with improved specificity to human cancer-embryonic antigen.

12 cl, 6 dwg, 8 tbl, 9 ex