Stimulated lymphoid cells of B lineage, but not plasma or myeloid cells, can express E receptor.

After culture with 20-30% autologous or allogeneic T cells and PHA, at least a proportion of the pathological cells from a variety of B-cell proliferations (common acute lymphoblastic leukaemia, prolymphocytic leukaemia, non-Hodgkin's lymphoma with blood involvement by mature lymphoid (cleaved and non-cleaved) cells) expressed true endogenous sheep erythrocyte (E) receptors. In contrast, plasma cells and a variety of myeloid cells failed to express E receptors after similar in vitro stimulation. These data, taken in conjunction with previous findings with B cells from normals and patients with hairy-cell and chronic lymphocytic leukaemia, suggest that B cells earlier than plasma cells can express E receptors after appropriate stimulation. The findings provide an in vitro counterpart of the leukaemic proliferations expressing both E receptor and surface immunoglobulin described from various laboratories, and further question the lineage specificity of the E receptor.