Multiple myeloma is a B-cell malignancy. One of novel anti-myeloma therapies is immunotherapy. Identification and use of novel, more potent tumor antigens are urgently needed to improve the effectiveness of the treatment. The purpose of this project is to seek and identify a new antigen DKK1 as a potentially important antigenic target to generate myeloma-killing T cells and then to examine whether these T cells could kill the myeloma cells in test tubes and a mouse model. As a result, this study may open a new avenue to eradicate tumor cells in myeloma patients in the future.