Carcinoembryonic antigen-immunoglobulin Fc fusion protein (CEA-Fc) for identification and activation of anti-CEA immunoglobulin-T-cell receptor-modified T cells, representative of a new class of Ig fusion proteins.
Chimeric immunoglobulin-T-cell receptor (IgTCR)-modified T cells ("designer T cells") kill tumor cells based on antibody-redirected recognition of tumor-associated antigen. Anti-carcinoembryonic antigen (CEA) designer T cells have been prepared and applied in adoptive cellular immunotherapy regimens for CEA-positive cancers. A CEA-immunoglobulin Fc (CEA-Fc) fusion protein was created from the A3B3 region of CEA and the Fc portion of human IgG for the purposes of activation and detection of anti-CEA designer T cells. CEA-Fc was expressed at high yield in CHO cells and purified to homogeneity in a single step on a protein A affinity column. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis revealed that CEA-Fc formed disulfide-linked dimers with a molecular weight of about 170 kDa and a monomer size of 85kDa. The A3B3 CEA component of the CEA-Fc bound to anti-CEA monoclonal antibody MN-14, as well as to the single-chain Fv (sFv) derived from this antibody that was expressed in the IgTCR on the surface of designer T cells. The Fc portion of CEA-Fc was recognized by anti-human IgG Fc antibody and bound by human monocyte Fc receptors. CEA-Fc activated the anti-CEA designer T cells as plate-bound or monocyte-bound form but not as soluble form, as measured by CD69 expression and T-cell proliferation. Our results indicate that the CEA-Fc fusion protein can be used to detect the expression of the anti-CEA IgTCR chimeric receptors on the modified T cells, as well as to serve as an antigen to activate the anti-CEA IgTCR modified T cells. CEA-Fc is the prototype for a new class of antigen-Fc molecules that may significantly augment the analytic and therapeutic goals of adoptive designer T-cell immunotherapies.
Division of Hematology-Oncology, Beth Israel Deaconess Medical Center and Harvard Institute of Human Genetics, Harvard Medical School, Boston, Massachusetts 02115, USA.
Qiangzhong
Q
Ma
Luisa
L
DeMarte
Yawen
Y
Wang
Clifford Paul
CP
Stanners
Richard Paul
RP
Junghans
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D061067:Antibodies, Monoclonal, Humanized; D016466:CHO Cells; D002272:Carcinoembryonic Antigen / Q000235:genetics* / Q000276:immunology*; D006224:Cricetinae; D003412:Cricetulus; D005434:Flow Cytometry; D005822:Genetic Vectors / Q000235:genetics; D006801:Humans; D007141:Immunoglobulin Fc Fragments / Q000235:genetics / Q000276:immunology; D019169:Jurkat Cells; D008213:Lymphocyte Activation / Q000276:immunology; D009369:Neoplasms / Q000628:therapy; D011948:Receptors, Antigen, T-Cell / Q000032:analysis / Q000235:genetics / Q000276:immunology*; D011971:Receptors, Immunologic / Q000032:analysis / Q000276:immunology* / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000032:analysis / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D013601:T-Lymphocytes / Q000276:immunology*; D014162:Transfection
D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D002272:Carcinoembryonic Antigen; D007141:Immunoglobulin Fc Fragments; D011948:Receptors, Antigen, T-Cell; D011971:Receptors, Immunologic; D011993:Recombinant Fusion Proteins; C110010:labetuzumab