Some chronic lymphocytic leukemia cells bearing surface immunoglobulins share determinants with T cells.

One set of antigens is common to some chronic lymphocytic leukemia (CLL) cells bearing surface immunoglobulins (Ig) and normal T cells. Proliferating cells from thirty-eight patients were studied with four antisera recognizing normal human T but not B cells. These antisera were raised in rabbits against (a) Sezary cells, (b) blood lymphocytes from a patient with sex-linked agammaglobulinemia, (c) T lymphoblasts and (d) thymus cells. In four CLL cases, the cells expressed the receptor for sheep erythrocytes and lacked surface Ig. Cells from thirty-four CLL cases bore monoclonal surface Ig and did not bind sheep erythrocytes. Twelve out of these thirty-four cases of CLL had cells which were lysed by one or, more frequently, by the four anti-human T cell xenoantisera. By absorption experiments, one set of at least three antigens common to the cells of some of these CLL and T cells was defined. Depending on the patient, the cells can either carry one, some or all of the antigens of this set. However, it was also demonstrated by absorption that these cells lacked antigens particular to the T cell lineage, while the cells from T CLL cases carried both sets of antigens.