Plasma cell surface antigen on human blood lymphocytes

Abstract

THERE is considerable evidence that lymphocytes bearing immunoglobulins on their surfaces are present in the peripheral blood of various animal species as well as man^1–3. Takahashi et al.⁴ indicated that neoplastic, as well as normal mouse plasma cells, contained specific surface alloantigens. These plasma cells do not, however, contain surface immunoglobulin determinants⁵. Harris et al.^6,7 demonstrated that neoplastic plasma cells of the mouse could be used to prepare specific antisera against normal plasma cells. These anti-plasma cell sera (APS) were found to suppress specifically primary and secondary humoral immunity without apparently affecting cellular immunity. Recently, we established a long term culture of human plasma cells⁸ from a localised plasmacytoma tumour of a patient with multiple myeloma. The cultured cells morphologically resembled plasma cells, and they secreted an IgG immunoglobulin antigenically identical to the patient's myeloma protein. Using cells from this source, an anti-human plasma cell serum (HuAPS) has been prepared which recognises a surface antigen on human plasma cells.