Anti-CD3 × anti-GD2 bispecific antibody redirects T-cell cytolytic activity to neuroblastoma targets.
BACKGROUND
The ganglioside GD2 is an attractive target for immunotherapy of neuroectodermal tumors. We tested a unique bispecific antibody anti-CD3 × anti-GD2 (3F8BiAb) for its ability to redirect activated T cells (ATC) to target GD2-positive neuroblastomas.


METHODS
ATC were generated from normal human peripheral blood mononuclear cells (PBMC) by stimulating the PBMC with OKT3 and expanding the T cells in the presence of interleukin 2 (IL-2) for 14 days. ATC were armed with 3F8BiAb (100 ng/10(6)  cells) or Her2BiAb (50 ng/10(6)  cells) prior to use. 3F8 BiAb were tested for its dual-binding specificity to GD2 expressed on cancer cell lines and CD3 expressed on ATC. 3F8BiAb-armed ATC were further tested ex vivo for their cytotoxicity against GD2 positive tumor targets and its ability to induce cytokine response upon binding to targets.


RESULTS
GD2 expression in neuroblastoma cells was confirmed by FACS analysis. Specific binding of 3F8BiAb to the tumor targets as well as to ATC was confirmed by FACS analysis. 3F8BiAb-armed ATC exhibited specific killing of GD2 positive neuroblastoma cell lines significantly above unarmed ATC (P < 0.001). GD2BiAb-armed ATC secreted significantly higher levels of Th(1) cytokines and chemokines compared to unarmed ATC (P < 0.001).


CONCLUSIONS
These preclinical findings support the potential of a novel immunotherapeutic approach to target T cells to neuroblastoma.
Department of Oncology, Wayne State University, Barbara Ann Karmanos Cancer Institute, Detroit, MI 48201, USA. myankele@med.wayne.edu
Maxim
M
Yankelevich
Sri Vidya
SV
Kondadasula
Archana
A
Thakur
Steven
S
Buck
Nai-Kong V
NK
Cheung
Lawrence G
LG
Lum
D018033:Antibodies, Bispecific / Q000276:immunology* / Q000627:therapeutic use; D001666:Binding Sites, Antibody; D017252:CD3 Complex / Q000276:immunology*; D045744:Cell Line, Tumor; D016207:Cytokines / Q000378:metabolism; D003601:Cytotoxicity Tests, Immunologic; D005732:Gangliosides / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D007167:Immunotherapy; D008213:Lymphocyte Activation; D009447:Neuroblastoma / Q000276:immunology* / Q000378:metabolism / Q000628:therapy; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000276:immunology / Q000378:metabolism; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*
D018033:Antibodies, Bispecific; D017252:CD3 Complex; D016207:Cytokines; D005732:Gangliosides; D018719:Erb-b2 Receptor Tyrosine Kinases; C019403:ganglioside, GD2