Alloreactivity of circulating DCs (PBDCs) and DCs derived from CD14⁺ monocytes (Mo-DC) from the same MM patients and of PBDCs from healthy subjects.

Increasing numbers of DCs were tested for their capacity to stimulate 5 × 10⁴ allogeneic CD3⁺ cells. The negative control, which gave 1800 ± 160 cpm when 12 500 cells were tested, is represented by unmanipulated mononuclear cells. Results report the mean ± SD of 3 different experiments. Statistical analysis demonstrated that both myeloma Mo-DCs and circulating DCs from healthy controls were more efficient stimulators of allogeneic T cells than PBDCs from MM patients (P < .01).