Elimination of malignant clonogenic cells from human bone marrow using multiple myeloid cell-specific monoclonal antibodies and complement.

Single or combined monoclonal antibodies (McAbs) Zh53, Zh820, and Zh2-1 have been used to eliminate malignant clonogenic cells from human bone marrow. The test of cytotoxicity showed that all of these McAbs could express high specific cytotoxic action against HL-60 cells and were selectively complement-dependent cytotoxic to various types of fresh leukemic cells. Clonogenic assay detected that single treatment with antibody and rabbit complement (RC) could reduce clonogenic units of HL-60 cells by more than 2 logs and two treatments reduced clonogenic units by more than 4 logs. However, combination of 2 McAbs could reduce clonogenic units by 4-5 logs. The data suggest that multiple treatments with McAbs and RC or a combination of 2 McAbs are more effective than a single treatment in eliminating clonogenic tumor cells. Treatment of normal human bone marrow with Zh53, Zh2-1 and RC did not produce a loss of normal CFU-GM, but treatment with Zh820 reduced the clonic units of normal CFU-GM by 24%.

The effectiveness of benzoate in the management of seizures in nonketotic hyperglycinemia.

Patients with nonketotic hyperglycinemia generally have intractable seizures that are poorly responsive to anticonvulsant medication. No effective treatment has been consistently reported. In three patients with nonketotic hyperglycinemia, the oral administration of sodium benzoate in dosages designed to lower the cerebrospinal fluid concentration of glycine was followed by an abrupt change from frequent major seizures before treatment to no seizures, or only occasional minor ones, after treatment. This attenuation of seizures was associated with a decrease in the concentrations of glycine in both plasma and cerebrospinal fluid. There was no evident change in psychomotor development.