Cytotoxic effect of immunoconjugate composed of glucose-oxidase coupled to an anti-ganglioside (GD2) antibody on spheroids.
As a new treatment protocol for neuroblastoma, the chimeric (human/mouse) antiganglioside GD2 antibody chl4.18 is being clinically tested. To improve the therapeutic effect of the antibody alone, we are currently investigating the cytotoxicity of glucose-oxidase coupled to the antibody chl4.18 on spheroids of the neuroblastoma cell line SK-N-LO. The cytotoxic effect of glucose-oxidase is achieved by the production of hydrogenperoxide (H2O2) and probably by the following reaction of H2O2 with iron to form hydrogen radicals (OH.). The cytotoxicity of glucose-oxidase was measured by two viability tests (MTT and WST 1). After a 4 hour treatment of the spheroids with the immunoconjugate, a reduction of viability to 50% (MTT-test) and 25% (WST 1-test), respectively, was obtained. The difference between the results of these two tests, might be explained by the different measurement protocols.
Heiss
P
P
Nuklearmedizinische Klinik der Technischen Universität München, Germany.
Bernatz
S
S
Bruchelt
G
G
Senekowitsch-Schmidtke
R
R
D000911:Antibodies, Monoclonal / Q000627:therapeutic use*; D005732:Gangliosides / Q000276:immunology*; D005949:Glucose Oxidase / Q000627:therapeutic use*; D006801:Humans; D018796:Immunoconjugates / Q000627:therapeutic use*; D009447:Neuroblastoma / Q000473:pathology / Q000628:therapy*; D018874:Spheroids, Cellular; D014407:Tumor Cells, Cultured
D000911:Antibodies, Monoclonal; D005732:Gangliosides; D018796:Immunoconjugates; C019403:ganglioside, GD2; D005949:Glucose Oxidase