Elimination of small cell carcinoma of the lung from human bone marrow by monoclonal antibodies and immunomagnetic beads.

The majority of patients with small cell carcinoma of the lung (SCCL) have bone marrow involvement detected by monoclonal antibodies (mAb). High dose chemotherapy followed by autologous bone marrow transplantation may improve treatment results for patients with SCCL, but the bone marrow may need to be purged of contaminating tumor cells. This study investigates the reactivity of a panel of mAb with two SCCL cell lines and normal bone marrow and the ability of the mAb and immunomagnetic beads to eliminate the SCCL cells from a mixture of 90% normal bone marrow cells and 10% SCCL cells. The mAb and immunomagnetic beads removed 4 to 5 log of SCCL cells in the model system. The immunomagnetic separation did not significantly adversely affect normal hematopoietic progenitor cells, as determined by bone marrow colony-forming units. The results suggest that the mAb and immunomagnetic beads could safely and effectively separate SCCL cells from the bone marrow for autologous bone marrow transplantation following high dose chemotherapy.