Flow cytometric analysis of the expression of CD59 and MHC class I on the target cells.

Cells positive and negative for GPI were prepared from myeloid (K562) and lymphoid (B, JY-5; T, MOLT-4) cell lines. CD59 was missing from GPI⁻ cells but appeared on the control counterparts (GPI⁺ cells) (A). The pair of the mutant (GPI⁻) and control (GPI⁺) cells of each cell line expressed the MHC class I equally (B). Dotted lines show nonspecific background staining with isotype-matched mouse Ig instead of MoAb.