Cytotoxicity assay with antibodies to CD59.

Killing of target cells by NK cells was not inhibited by MoAb to CD59. K562 cells with (▪) and without (■) PIG-A mutation were cocultured with NK cells (2E3) at E/T ratio (2:1) in the presence of 10 μg/mL MoAb to CD59. IgG2a, isotype-matched mouse Ig; p282 and MEM43, 2 clones (representatives of 8) of MoAb (IgG2a) to CD59. Each value represents the mean (± SD) of triplicate assays.