Autologous bone marrow transplantation for myeloma patients using PNA- and CD19-purged marrow rescue.

A new method of in vitro bone marrow purging using a lectin and monoclonal antibody in combination has been used for the first time in vivo. Two patients with advanced myeloma were treated with high-dose melphalan and total body irradiation and then rescued with autologous bone marrow which had been purged in vitro to remove malignant cells by using a combination of a plasma cell-binding lectin (peanut agglutinin, PNA) and the anti-B lymphocyte monoclonal antibody anti-CD19, bound to magnetised microspheres. Both patients showed rapid engraftment of the purged bone marrow and remain well 36 and 46 months later with normal bone marrow morphology, although one patient still has a low level of circulating paraprotein. This is a promising form of therapy for what has been an invariably fatal condition.