Rosette formation in chronic lymphocytic leukemia: studies of lymphocytes from peripheral blood and lymph node biopsy.

Lymphocytes were obtained from a lymph node biopsy from a patient with chronic lymphocytic leukemia in whom B and T lymphocytes were present in equal percentages in the peripheral blood. The lymphocytes were examined for rosette formation with mouse and sheep erythrocytes in order to determine whether the leukemic process was of the B or T cell type.