Enrichement of PHA-Responsive Lymphocytes in Chronic Lymphocytic Leukaemia after Removal of Ig-Bearing Cells

Lymphoid cells from the peripheral blood of subjects with chronic lymphocytic leukaemia (CLL) were found to be poorly stimulated with phytohaemagglutinin (PHA) in vitro. Approximately 90 % of the cells had membrane bound Ig molecules. Enrichement of the non-Ig bearing cells by passage through bead columns coated with human Ig and rabbit anti-human antibody resulted in an increment of the relative PHA-responsiveness of the cells. The results indicate that the low PHA-respon-siveness of lymphoid cells from CLL-patients is due to the fact that the normal PHA-responsive lymphocytes are massively contaminated with leukaemic, unresponsive cells which bear surface Ig.