Human long-term bone marrow cultures (HLTBMCs) in myelomatous disorders.

Human long-term bone marrow cultures (HLTBMCs) were established with bone marrow (BM) collected from five patients with myelomatous disorders (four with multiple myeloma, one with plasma cell leukemia). In all cases, up to at least 6 weeks of culture, there was a persistence of the monoclonal plasma cell population in the adherent layer of the culture. In some cultures proliferating plasma cells could be demonstrated by the Ki-67 monoclonal antibody. In all instances a paraprotein could be shown in the conditioned medium. This study demonstrates that malignant plasma cells, in analogy to their normal counterparts, have an affinity for the BM stroma and suggests that their long-term survival might be enhanced by their interaction with it.