| abstract |
CD38 is also expressed in a variety of malignant hematological diseases, including multiple myeloma. In the present invention, the inventors have generated a new antibody against CD38 that could be suitable for producing bispecific antibodies as well as CAR-T cells. In particular, the inventors report the development of Bi38-3, a new bispecific T cell engager that targeted CD38 on MM cells and recruited cytotoxic T cells through the CD3ε. Bi38-3 lacked the Fc region of natural mAb, which contributes to resistance processes, but triggered T cells to proliferate, release cytokine and lyse CD38 positive MM cells in vitro. Similarly, Bi38-3 induced autologous T cells to eliminate tumor plasma cells isolated from MM patients both at diagnosis and at relapse. The cytotoxicity triggered by Bi38-3 was restricted to cells expressing high levels of CD38 and preserved the integrity of T, B and NK lymphocytes in vitro. Importantly, Bi38-3 rapidly reduced tumor cells in an MM1.S xenograft mouse model of human MM. Taken together, the results show that the antibody of the present invention is an effective reagent to specifically eliminate CD38 positive malignant cells without significantly affecting CD38 lowly expressing cells and represents a promising novel immunotherapeutic tool for the treatment of malignant hematological diseases, and especially multiple myeloma. |