Surface immunoglobulins of lymphocytes in chronic lymphocytic leukemia and disseminated lymphosarcoma

Changing clinical, morphological and immunological patterns in chronic lymphocytic leukaemia

Two cases of chronic lymphocytic leukaemia are presented in which, in the terminal phase of the disease, a population of abnormal lymphocytes similar to those seen in lymphosarcoma cell leukaemia replaced the morphologically normal small lymphocytes observed previously. Immunologically, this change coincided with a striking alteration in the pattern of surface immunoglobulin markers. In both cases, most cells initially carried IgM and in both cases these were replaced by cells carrying IgG as the number of abnormal lymphocytes increased. In addition, the use of anti-delta antiserum in the second case revealed the coexistence of large numbers of IgD-bearing lymphocytes as well. Calculations showed that more than half the cells present at that time must have been carrying both IgD and IgG surface markers.

Cell receptor studies on seven cases of diffuse histiocytic malignant lymphoma (reticulum cell sarcoma)

Expression of B and T lymphocyte receptors has been studied in seven cases of reticulum cell sarcoma. In one case, surface receptors and tests of phagocytic function demonstrated the histiocytic origin of the neoplastic cells. In four cases, tumour cells expressed both B and T lymphocyte markers (two cases) or showed a normal pattern of expression of B and T lymphocyte markers. In the other two cases, lymphocyte receptors were not detected, and there was no evidence of phagocytic function: this class of receptor-silent tumours is of uncertain pathogenesis. The significance of these observations is discussed.