In-vitro cytolysis of myeloma tumor cells with glucose oxidase and lactoperoxidase antibody conjugates.

We have assessed the tumoricidal potential of enzyme-antibody conjugates on murine myeloma cells. Conjugates of glucose oxidase (EC 1.1.3.4) and lactoperoxidase (EC 1.11.1.7) were specifically targeted on the NSO tumor cells. Optimal conditions for tumor cell killing, as assayed by [51Cr] release required the binding of both antibody conjugates to the cell membrane. This is followed by washing and incubation in medium containing glucose and 0.1 mM iodide. Under these conditions 90% of the incorporated [51Cr] labeled is released from the cells, and NSO clonogenicity is reduced by a factor greater than 5 logs by 2 h of incubation.