Cytotoxic T-cell activity against fresh autologous myeloma cells.

A T-cell line was established by coculturing PBMC from patient HR with autologous dendritic cells (DCs) pulsed with myeloma Id. (A) The T-cell line was assayed at the indicated ratios of effector to target for lysis of chromium 51–labeled autologous plasmacytoma cells (solid bars) or natural killer–sensitive K562 cells (open bars) after repeated stimulation. (B) The T cells were assayed for lysis of indium 111–labeled autologous tumor cells. Tumor-specific cytotoxicity was blocked by pretreatment of tumor targets with an anti-MHC class I MoAb but not with a control antibody. Autologous normal B cells were used as a control target for specificity. The results shown are representative of 2 experiments.