[Genetic traits in the area of Bodrogköz]

In 1984 a late malaria endemic area, called Bodrogköz was studied. This was a reexamination of the population genetic work performed by Walter, Nemeskéri. In six villages of Bodrogköz 328 persons were tested for AB0, Rh blood groups, haptoglobins, haemoglobin concentration, haematocrit, erythrocyte amount, the MCV, the MCH and the G-6-PD were analyzed. The quantitative determination of HbF and HbA2, red cell osmotic resistance and thalassemia were measured as well. Thalassemia heterozygote carriers and an increased level of HbF were revealed. The frequency of G-6-PD deficiency was 0.39%. In Bodrogköz the frequencies of AB0, Rh and haptoglobin types were similar in the present and all previous studies. The background of this similarity might be the genetic similarity between two following generations. On the basis of these facts, the Hb0 Arab and partially DNA work we suggested an alternative hypothesis that these mutant genes got into Bodrogköz by the rather later migration than with ancient Hungarian people during the period of conquest of Hungary.

[The era of molecular genetics. New perspectives in hematology]

The unprecedently swift developments in molecular genetics opened up a new era in haematology. The regulation of the expression of globin genes and its coordination with the expression of genes coding for other red cell specific proteins, as well as molecular genetics of some intrinsic haemolytic anaemias and the clinically important recent results revealing the genetic regulation of iron metabolism are discussed. New unfolding concepts of the physiological regulation of the haemopoetic stem cell and the multistep development of its malignant transformation are reported. The unlimited possibilities rendered by the rDNA technology in diagnostics and therapy of haematological diseases is pointed out. The present state of art of gene therapy including the first trials with gene transplantation in humans is discussed.

[Importance of the detection of minimal residual disease in the management of acute leukemia]

Between 1984-1988, 57 adult acute leukemic patients were treated with intensive combined chemotherapy in the National Institute of Haematology and Blood Transfusion. For the evaluation of response to therapy, 4 investigations were performed in parallel: bone marrow aspirate, bone marrow biopsy, cytogenetic analysis and bone marrow culture. Nonparametric test for samples taken for the evaluation of remission status showed that bone marrow biopsy was significantly the most sensitive method for the detection of residual disease. The bone marrow culture was also on the borderline of significance, but the low CFU-GM level did not always correlate with the further clinical course. Occasionally, karyotypic abnormality was the only sign of the residual disease. It would be of great importance to quantitate the minimal residual disease in order to evaluate and compare the various intensive postinduction therapeutic strategies.

[Hepatitis C virus antibody in Hungarian blood donors, persons at risk and patients with post-transfusion hepatitis]

The authors screened blood donors, persons at high risk of infection and patients with post-transfusion hepatitis by the use of the new hepatitis C antibody test. 1.7% of persons donating blood acceptable for use according to current criteria were found positive. This ratio was markedly higher among donors displaying an elevated transaminase level. Among the various patients tested 85% of the haemophiliacs, 14% of the transfused haematology patients, and 40% of those on dialysis were found positive. In two groups of patients with post-transfusion non-A, non-B hepatitis the ratio of positives was 69% and 92%, respectively. The frequency of hepatitis C antibody was not sizably higher in the health personnel tested than that found in blood donors. The results indicate hepatitis C virus to be the main source of post-transfusion non-A, non-B hepatitis in Hungary too. As expected, HBc antibody revealing a previous contact with hepatitis B virus was found very frequent in patients with coagulopathies and in those on dialysis. A relatively high anti-HBc prevalence was found among health personnel and blood donors too. Authors intend to emphasize the need of thorough consideration of indications in hemotherapy although improvements in the screening of donations can diminish the risk of virus transmission by blood or blood derivatives.

[Correlation of HLA antigens and idiopathic hemochromatosis in Hungary]

The aim of our present work was to collect data on HLA distribution in patients with idiopathic haemochromatosis in Hungary. Ten unrelated patients with idiopathic haemochromatosis (6 men, 4 women) were studied. Idiopathic haemochromatosis was diagnosed on clinical, biochemical and histological grounds. HLA typing was performed in 10 probands and in all of their first degree relatives available (24) through 7 pedigree studies. HLA A3 was present in 6 of 10 probands [6/10 vs. 18.8% in the group of healthy blood donors (No 53) and 22.4% in Hungarian population (No 1910]. HLA B7 was present in 4 of 10 probands (40% vs. 11.3% and 14.6%). A3B7 antigen association has been found in 4 of 10 patients. A3B7 and A2B38 haplotypes were present twice in 4 of 7 genotyped probands. Pedigree studies revealed one nonaffected homozygote, 17 heterozygotes and 6 non carriers. Extended family and population studies are necessary to establish the gene frequency in Hungary and the probability of the involved haplotypes other than A3B7.

[Heterogeneity of surface antigens in chronic B-cell lymphoid leukemia]

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.

[Cytochemical, immunologic and gene rearrangement studies in adult acute leukemia]

Results of morphological, cytochemical and immunological studies performed in adult acute leukaemias have been compared. Thirty one cases proved to be acute myeloid leukaemia, while 25 cases were shown to be acute lymphoid leukaemia. Based on our results we conclude that immunophenotyping with monoclonal antibodies does not help in distinguishing the subtypes of AML. For purposes of clinical diagnosis cytochemical methods are valuable. On the other hand the monoclonal antibodies are essential in distinguishing the very immature myeloid and lymphoid leukaemias and this is of great importance from the clinical point of view, in determining therapy. Moreover, the diagnosis of acute lymphoid leukaemias is not possible without the specific monoclonal antibodies. Their application is first of all in haematological centers caring for leukaemia patients nowadays already obligatory. Gene rearrangement studies make the diagnosis more accurate and help in the diagnosis of leukaemias of unknown immunological origin.

[Granulocyte-macrophage progenitor cells in allogenic bone marrow transplantation: correlation of progenitor cell content and regeneration in the graft]

The amount of granuloid macrophage progenitors (CFU-GM) was studied in 16 donor bone marrows used for allogenic bone marrow transplantation in the National Institute of Haematology and Blood Transfusion between January, 1984 and January, 1988. In 10 bone marrow transplanted patients long-term follow up of bone marrow CFU-GM regeneration was carried out. Graft sizes were the following: 2.91 +/- 0.62 X 10(8)/kg body weight nucleated cells and 19.2 +/- 14 X 10(4)/kg body weight (CFU-GM. Preinfusion procedures (centrifugation and resuspension) did not alter CFU-GM content of the grafts. Separation of nucleated cells with hydroxyethylstarch, applied for ABO mismatched donor bone marrow, however, resulted in a 30 per cent loss in CFU-GM. Since higher than threshold graft-sizes for successful engraftment were used, no linear correlation between graft size and speed of granulocyte and platelet recovery was found. Significant difference between regeneration kinetics of bone marrow CFU-GM of patients transplanted for CML or AML and ALL was observed: in AML and ALL patients normal bone marrow CFU-GM level was found 4 to 6 months after transplantation, while in CML patients CFU-GM level approached the lower limit of the normal value only 10 to 14 months after transplantation. Granulocyte and thrombocyte recovery of CML patients showed a significant delay when compared to transplanted AML and ALL patients.

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).