[Heterogeneity of surface antigens in chronic B-cell lymphoid leukemia]. / A sejtfelszíni antigének heterogenitása B-sejtes krónikus lymphoid leukaemiában.

Clinical and immunological studies of fifty patients with CLL have been performed. No correlation was found either between the clinical stage or clinical course of the disease and the distribution of cell surface makers characteristic of CLL (CD19, CD20, CD21, HLA-DR, sIg). Therapy did not influence the distribution of B lymphocyte subpopulations. On the other hand we recognized differences when examining the B-cell specific features. The CD21 antigen was present in significantly lower proportion when compared to all other B-cell markers. This suggests the presence of immature B-cell population. Correlation studies showed a strong correlation between the presence of the CD5 antigen and the antigens CD19, CD20, HLA-DR and sIg, while a similar correlation could not be proved between the CD5 antigen and CD21 marker. Thus the application of the CD5 antibody together with any of the B-cell markers seems to be sufficient for the diagnostics of CLL with the exception of the CD21 antibody that marks only a small proportion of the B-cell population in CLL, so it can be used for purposes of clinical diagnostics.

Detection of Activation Antigens on Chronic Lymphocytic Leukaemia Cells.

The peripheral blood mononuclear cells of patients with chronic lymphocytic leukaemia were characterized by the presence of a variety of cell surface differentiation antigens. The cells of 20 patients were found to be of B-cell phenotype when studied with antibodies directed against CD19, CD20, HLA-DR and sIg. Furthermore, a significant percentage of the cells gave a positive reaction with the monoclonal antibody to CD5. On the other hand, the CLL-cells did not express the CD21 antigen (C3d receptor, EBV receptor). We studied in parallel the presence of various activation antigens using 19 monoclonal antibodies grouped into 7 clusters (CD25, CD30, CD40, CD69, CD70, CD39, CD71). A significantly higher percentage of the CLL cells expressed activation antigens than lymphocytes from healthy controls. The percentage of CD3/HLA + DR + cells, compared to the healthy control lymphocytes was not increased in the CLL patients, and the activated cells in CLL were found to have characteristics of B-cells. Based on these results, we suggest that the CLL cells, like the cells in Hodgkin's disease and T-cell lymphoma, are not resting, but activated B-cells or the neoplastic abberrants of activated cells.

Plasma lactoferrin levels in leukaemias.

A solid-phase, one-step radioimmunoassay was developed for the determination of plasma lactoferrin concentration. The detection limit of the assay is 150 micrograms/l. Leakage of cellular lactoferrin was minimal when EDTA was used as anticoagulant, while results obtained from serum and from heparinized plasma were not reproducible. The plasma lactoferrin concentration of 35 female and 44 male healthy adults was measured in order to determine normal values. The geometric mean of lactoferrin levels in men is about 10% higher than in women: 483 (200-1500) micrograms/l in men and 446 (200-870) micrograms/l in women. Patients with acute and chronic leukaemias were also studied. In 38 patients with chronic myeloid leukaemia plasma lactoferrin levels were increased by three times while the neutrophil count was ten times higher than normal. Normal lactoferrin concentrations were measured in plasma samples from 15 patients with chronic lymphocytic leukaemia in incomplete remission while no detectable lactoferrin was found in samples from those in relapse (10 patients). In the untreated patients or those in relapse (19 cases) of both acute lymphocytic and myeloid leukaemias, plasma lactoferrin concentrations were undetectable while they seemed to return to normal during remission (3 cases). The data obtained indicate that the determination of plasma lactoferrin concentration might play an important role in facilitating the assessment of total blood granulocyte pool (TBGP).

Platelet phospholipids in thrombocytosis due to myeloproliferative disorders.

Platelet phospholipids were analyzed in patients with thrombocytosis due to myeloproliferative disorders and secondary thrombocytosis. A significant increase of phosphatidylcholine together with a decrease of sphingomyelin was observed in each of the 8 patients with primary thrombocythaemia and in each of the 5 patients with excessive thrombocytosis due to primary polycythaemia. The phospholipid pattern of the 3 patients with secondary thrombocytosis did not differ from that of the normal controls. This marked difference in the platelet phospholipids may be helpful in distinguishing secondary thrombocytosis persisting for a prolonged period of time after splenectomy from previously unrecognized primary thrombocythaemia unmasked by splenectomy. The decreased sphingomyelin/lecithin ratio of platelets in primary thrombocythaemia may interfere with platelet function by increasing the fluidity of their membrane.