Establishment and characterization of a CD5 positive, immunosuppressive human myeloma cell line

A continuously growing, in vitro cell line with plasma cell characteristics has been established from the bone marrow of a patient with multiple myeloma. Surface marker characterization of the cells revealed a combination of markers normally associated with different developmental stages in the B cell lineage. The cell secretes immunoglobulin at a relatively low rate. The cell also expresses CD5 and secretes a factor which suppresses in vitro mitogen and antigen induced immunoglobulin synthesis by normal PBL.