Recombinant human monoclonal igA antibody against CEA to recruit neutrophils to CEA-expressing cells.
IgA is able to trigger antibody-dependent cellular cytotoxicity (ADCC) by recruiting neutrophils expressing the Fc receptor for the CHalpha chain. We herein describe the preparation of a human recombinant anti-CEA IgA antibody to kill carcinoembryonic antigen (CEA)-expressing tumor cells via ADCC by neutrophils. A single chain Fv (scFv) gene was constructed using a cDNA library of a hybridoma clone that produces a human anti-CEA monoclonal IgG4 (C2-45). The scFv gene, linked with a CHalpha gene, was inserted into the pBK283 vector, which was cotransfected into BmN4 insect cells with the wild-virus BmNPV. After cloning and amplification, the recombinated virus was injected into silkworm larvae. The resulting human recombinant IgA, designated as 45scFvLCHalpha, was purified from hemolymph by Ni-affinity chromatography and characterized by ELISA, Western blotting, and the ADCC assay. 45scFvLCHalpha with an IgA antigenicity was bound to CEA and showed effective killing of the CEA-expressing cells in the presence of IFN-gamma-activated neutrophils. These data suggest the recombinant anti-CEA IgA antibody recruiting neutrophils maybe a useful means for the antibody-based immunotherapy of human CEA-expressing tumors.
Zhao
Jun
J
Molecular Oncology Center, Faculty of Medicine, Fukuoka University, Fukuoka 814-0180, Japan.
Kuroki
Motomu
M
Shibaguchi
Hirotomo
H
Wang
Lin
L
Huo
Qun
Q
Takami
Noboru
N
Tanaka
Toshihiro
T
Kinugasa
Tetsushi
T
Kuroki
Masahide
M
D000818:Animals; D000911:Antibodies, Monoclonal / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology* / Q000494:pharmacology; D000920:Antibody-Dependent Cell Cytotoxicity; D012831:Bombyx; D016466:CHO Cells; D002272:Carcinoembryonic Antigen / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology*; D045744:Cell Line, Tumor; D006224:Cricetinae; D003412:Cricetulus; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D007070:Immunoglobulin A / Q000235:genetics / Q000276:immunology*; D007128:Immunoglobulin Fragments / Q000235:genetics / Q000276:immunology; D007135:Immunoglobulin Variable Region / Q000235:genetics / Q000276:immunology; D007167:Immunotherapy / Q000379:methods; D007371:Interferon-gamma / Q000494:pharmacology; D009504:Neutrophils / Q000187:drug effects / Q000276:immunology*; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology
D000911:Antibodies, Monoclonal; D002272:Carcinoembryonic Antigen; D007070:Immunoglobulin A; D007128:Immunoglobulin Fragments; D007135:Immunoglobulin Variable Region; D011994:Recombinant Proteins; D007371:Interferon-gamma