Common large partial VWF gene deletion does not cause alloantibody formation in the Hungarian type 3 von Willebrand disease population.

BACKGROUND: Type 3 von Willebrand disease (VWD) is an autosomal recessive bleeding disorder, characterized by virtually undetectable plasma von Willebrand factor (VWF) and consequently reduced plasma factor VIII levels. Genetic mutations responsible for type 3 VWD are very heterogeneous, scattered throughout the VWF gene and show high variability among different populations. METHODS: Twenty-five severe VWD patients were studied by direct sequencing of the 51 coding exons of the VWF gene. The total number of VWD type 3 families in Hungary is 24, of which 23 were investigated. RESULTS: Fifteen novel mutations were identified in 31 alleles, five being nonsense mutations (p.Q1238X, p.Q1898X, p.Q1931X, p.S2505X and p.S2568X), four small deletions and insertions resulting in frame shifts (c.1992insC, c.3622delT, c.5315insGA and c.7333delG), one a large partial deletion (delExon1-3) of the 5'-region, four candidate missense mutations (p.C35R, p.R81G, p.C295S, p.C623T) and one a candidate splice site mutation (c.1730-10C>A). Six previously described mutations were detected in 17 alleles, including the repeatedly found c.2435delC, p.R1659X and p.R1853X. Only one patient developed alloantibodies to VWF, carrying a homozygous c.3622delT. CONCLUSION: We report the genetic background of the entire Hungarian type 3 VWD population. A large novel deletion, most probably due to a founder effect, seems to be unique to Hungarian type 3 VWD patients with high allele frequency. In contrast to previous reports, none of the five patients homozygous for the large partial deletion developed inhibitors to VWF. This discrepancy raises the possibility of selection bias in some of the reports.

Two successful pregnancies following eight miscarriages in a patient with antithrombin deficiency.

Inherited thrombophilias are associated with an increased risk of maternal thromboembolism and certain adverse pregnancy outcomes, including second- and third-trimester fetal loss, placental abruption, severe intrauterine growth restriction, and early-onset, severe preeclampsia. Pregnant patients with severe thrombophilias, especially antithrombinopathies are at very high risk for both thromboembolism and adverse pregnancy outcomes. A case of a patient with antithrombin deficiency is reported, who had two successful pregnancies after eight miscarriages. Our case shows that a combined treatment with antithrombin substitution and a prophylactic, body-weight-adjusted dose of low-molecular-weight heparin may be successful in preventing pregnancy loss and thromboembolism in antithrombin deficiency during pregnancy, although other complications, such as preeclampsia and intrauterine growth restriction cannot always be prevented.

[Screening for carrier state of Haemophilia B using indirect genomic detection]. / Konduktorszúrés indirekt géndiagnosztika alkalmazásával B haemophiliában.

The authors report the first data having applied the indirect genomic diagnosis in carrier screening in Hungary. 22 patients with haemophilia B and female family members of 14 out of them were examined by PCR based restriction fragment length polymorphism analysis. The combined use of 3 intra- and 1 extragenic polymorphisms have been examined at the same population. DNA fragments, containing the single nucleotide change polymorphic site (Xmnl, Hhal, Taql), or the 50 bp insertion/deletion element (Dde) were amplified. The products were digested by the appropriate restriction digestion enzyme and were detected on agarose gel following ethidium-bromide staining. 20 siblings were interested in the determination of their carrier-state. 15 (75%) of them could get definite diagnosis. The carrier-state was established in 7 cases, excluded in 8 subjects. For the remaining 5 participants studied, the absence of the parental DNA sample caused uncertainty, while in 2 cases (10%) none of the analyzed RFLP was informative. The heterozygosity rate, the gene and haplotype frequency were also recorded and compared with the international data. The indirect methods have proved to be sufficient and well suitable for routine carrier testing. The results provide the basis of the subsequent prenatal diagnosis.

New diagnostic tool for differentiation of idiopathic hypereosinophilic syndrome (HES) and secondary eosinophilic states.

The hypereosinophilic syndrome (HES) is a very rare disease, characterized by persistent eosinophilia with tissue involvement and organ dysfunction which often precedes a subsequent T cell lymphoma. Interleukin-5 secreted by a T lymphocyte subpopulation has been described in previous reports as the most important factor responsible for the prolonged lifespan of the eosinophils. The goal of the present study was to describe a fast, simple diagnostic method for the differentiation of HES and secondary eosinophilic states. Beside the surface marker analysis of peripheral blood mononuclear cells (PBMC) we measured surface bound IgE molecules on lymphocytes and eosinophil cells, intracellular cytokines (IL-5, INFgamma) in CD4+ lymphocytes and eosinophil major basic protein (MBP) in eosinophils using flow cytometric detection method. The appearance of an IL-5 producing cell population with a decreased number of INFgamma positive lymphocytes was characteristic for the blood samples of HES patients. Predominance of Th2 cells with the appearance of a CD8+/CD3 /CD56+ cell population was restricted for the HES cases and could not be detected in secondary eosinophilic individuals. Our flow cytometric cytokine detection method (with parallel cell surface marker analysis) does not require cell separation or long term cell culture steps previously described for the detection of IL-5 producing cells. Therefore it seems to be a more appropriate approach for the differential diagnosis of primary and secondary eosinophilic states.

Identification of mutations in 15 Hungarian families with hereditary protein C deficiency.

Hereditary protein C deficiency represents about 2-9% of inherited thrombophilias. Our aim was to elucidate the molecular basis of protein C deficiency in 25 members of 15 Hungarian families with venous thromboembolic diseases and to identify hitherto undescribed genetical defects in the protein C (PROC) gene. The exons of the PROC gene were screened for mutations with the combination of polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE), and/or PCR and single-strand conformation polymorphism (SSCP) analysis. The amplified DNA fragments with aberrant migration during DGGE and SSCP were sequenced. Mutations were determined in the PROC gene in all of the examined families: one nonsense mutation, one rare frameshift deletion and nine different missense mutations, of which three were novel (1493 A-->G, 35Asp-->Gly; 6231 G-->A, 173Gly-->Glu; 8476 C-->T, 254Thr-->Ile). The combination of hereditary protein C deficiency with other hereditary thrombophilias was rather common. DGGE and SSCP were proved to be efficient and cost-effective screening methods in the genetic analysis of hereditary protein C deficiency.

Molecular biology and clinical manifestation of hereditary factor VII deficiency.

Inherited factor VII (FVII) deficiency is a rare autosomal recessive disorder. Mutations and polymorphisms of the FVII gene were characterized in more than 40 unrelated patients with FVII deficiency. Among the 29 different mutations, the most frequent were Ala294 Val, Ala294Val;404delC, IVS7+7, and Val281 Phe. Four novel mutations (IVS2+1G>C, Arg247 Cys, Glu265 Lys, Asp343 His) were detected. The relationships between genotypes of mutations and polymorphisms of the FVII gene, FVII deficiency, and clinical phenotype were investigated. Homozygosity of the Phe4 Leu, IVS4+1G>A, Cys135 Arg, Ala244 Val, and Ala294 Val;404delC and the double heterozygosity of Tyr68 Cys / IVS3-1G>A, Val252 Met / IVS2+5G>T, Val281 Phe / Cys135 Arg, Ala294 Val / Val281 Phe, Ala294 Val;404delC / Val281Phe, Ala294 Val;404delC / Arg152 stop, Ala294Val;404delC / Gln(-35) stop, Ala294 Val / Val252 Met, Ala294 Val / Gly156 Asp, and Thr359 Met / Asp242 His were related to clinical symptoms. Double heterozygotes for Arg247 Cys / IVS2+1G>C, Ala206 Thr / Pro303 Arg, Leu(-20) Pro / Val252 Met as well as IVS7+7 /Ala294 Val, IVS7+7 /Ala206 Thr, and IVS7+7 / Met298 Ile were asymptomatic. The clinical symptomatology is rather poor in correlation with the FVII activity. Concerning the clinical phanotype, a correlation seems to exist between specific mutations and clinical symptoms.

[The role of TNF-alpha in myelodysplastic syndrome: immunoserologic and immunohistochemical studies] . / A TNF alpha szerepének immunszerológiai és immunhisztokémiai vizsgálata myelodysplasiás syndromában.

TNF alpha is a highly active cytokine which plays an important role in the regulation of apoptotic cell death, a mechanism involved in the pathophysiology of myelodysplastic syndrome (MDS). In this study we investigated the expression of TNF alpha on the bone marrow trephine biopsies by immunohistochemical method and the TNF alpha production of peripheral blood mononuclear cells by ELISA method in 15 patients affected by MDS. Five of seven patients without excess of blasts showed high or intermediate TNF alpha expression in the bone marrow biopsies, whereas two patients with excess of blasts were negative and one had low expression. The five CMML patients revealed low or intermediate expression. The production of TNF alpha by the PBMC was analysed in 10 patients, four patients with RA and two with CMML produced higher level of TNF alpha which increased after stimulation with phorbol myristic acetate, but none of the RAEB patients revealed increase in TNF alpha production. In conclusion we suppose that increased TNF alpha expression and production by PBMC may be a further indirect evidence of the role of increased apoptosis in low risk MDS patients, in the course of progression the cytokine expression and production decreases.

[Detection of minimal residual diseases in B-cell tumors using PCR specific for the immunoglobulin heavy chain gene]. / A minimális reziduális betegség kimutatása B-sejtes tumorok esetében az immunglobulin nehézlánc génre specifikus polimeráz láncreakció segítségével.

In B-cell non-Hodgkin's lymphomas (NHL), clonal rearrangement of the immunoglobulin heavy chain (IgH) gene provides a useful marker for the detection of minimal residual disease (MRD) after treatment. To explore clinical usefulness of polymerase chain reaction (PCR) analysis of clonal IgH gene rearrangement in the detection of MRD a follow up study of 10 patients with B-cell NHL have been performed. At the time of diagnosis, tumor DNAs were PCR-amplified using sense primer specific for the heavy chain variable region (VH) and antisense primer specific for the heavy chain joining region (JH) of the IgH gene. The clonal rearrangement of IgH gene detected by PCR was used as clonal marker to determine MRD after treatment. In three cases, where clinical remission was not achieved, clonal IgH gene rearrangement was detected after the treatment. In seven cases, clinical remission was achieved after induction therapy but the PCR analysis revealed clonal IgH gene rearrangement in three of the cases. In all of the three cases, where MRD was detected by PCR, clinical relapse developed after 7-28 months of the therapy. In all cases that have relapsed, the IgH gene rearrangement was identical at the time of initial diagnosis and at the relapse. This study demonstrates that PCR analysis of clonal IgH gene rearrangement is a useful method to monitor and detect MRD before clinical relapse.

Detection of TNFalpha expression in the bone marrow and determination of TNFalpha production of peripheral blood mononuclear cells in myelodysplastic syndrome.

TNFalpha is a highly active cytokine which plays an important role in the regulation of apoptotic cell death, a mechanism involved in the pathophysiology of myelodysplastic syndrome (MDS). In this study we investigated the expression of TNFalpha of the bone marrow trephine biopsies by immunohistochemical method and the TNFalpha production of peripheral blood mononuclear cells by ELISA method in 15 patients affected by MDS. Five of seven patients without excess of blasts showed high or intermediate TNFalpha expression in the bone marrow biopsies, whereas two patients with excess of blasts were negative and one had low expression. The five CMML patients revealed low or intermediate expression. The production of TNFalpha by the PBMC was analysed in 10 patients, four patients with RA and two with CMML produced higher level of TNFalpha which increased after stimulation with phorbol myristic acetate, but none of the RAEB patients revealed increase in TNFalpha production. In conclusion we suppose that increased TNFalpha expression and production by PBMC may be an indirect evidence of the role of increased apoptosis in low risk MDS patients.

[Hepatitis C virus infection and B-cell non-Hodgkin's lymphoma]. / A hepatitis C vírus-infekció és B-sejtes non-Hodgkin-lymphoma.

Oncogenesis is a multifactorial process in which environmental, genetical and infectious factors may be of importance. Specific viruses are supposed to have etiological role in about 15% of human tumors. Recently the B-cell proliferation inducing effect of the hepatotropic and lymphotropic hepatitis-C virus (HCV) came into the limelight based on the high prevalence of HCV positivity in B-cell non-Hodgkin's lymphoma (NHL) patients. The aim of the authors was to establish the prevalence of HCV infection in NHL patients. Paralelly the HBV, CMV and EBV markers, and the alterations of the humoral immune response (immunoglobulins, cryoglobulins, rheumatoid factor) were determined. 42 patients (24 male, 18 female; the mean age: 54.1 years, range 22-80 years) classified as 16 indolent (low risk), and 25 aggressive (intermediate risk) NHL and one with very aggressive Burkitt's lymphoma, according to the modified REAL classification were examined. Enzyme-linked immunosorbent assay (ELISA) for HBsAg and anti-HCV, HBsAg, anti EBV, anti CMV, furthermore polymerase chain reaction (PCR) for HCV-RNA were used. Anti-HCV was found in 6/42 NHL patients (14.3%), while anti-HCV and/or HCV-RNA PCR positivity revealed on overall HCV infection in 10/42 (23.8%) patients. None of them were HBsAg positive. Our findings support the hypothesis, that HCV might have an aetiological role in the lymphoproliferation leading to B-cell NHL.

[Treatment of chronic myeloid leukemia with interferon-alpha]. / Chronicus myeloid leukaemia kezelése interferon-alpha-val.

The authors have treated 38 patients with chronic phase chronic myeloid leukemia in their single center in the last five years. Conventional chemotherapy provided about 40-50% hematological response, interferon-alpha seems to be more effective, complete hematological remission occurred in 65%. Interphase cytogenetics and fluorescein in situ hybridisation technique was used to measure the cytogenetic response. They observed complete cytogenetic remission in two cases (8%), major response in 11 (39%), minor response in 4 (15%) and minimal response in 4 cases (15%). Interferon-alpha is an effective, well-tolerated medicine in the treatment of chronic myeloid leukemia.

[Analysis of T-cell receptor gamma-gene rearrangement in lymphoproliferative disorders using polymerase chain reaction]. / A T-sejt receptor gamma-génátrendezödés vizsgálata lymphoproliferativ kórképekben polimeráz láncreakció segítségével.

T-cell non-Hodgkin's lymphomas (NHL) exhibit a clonal T-cell receptor (TCR) gamma gene rearrangement as a result of sequential assembly of their variable (V gamma) and joining (J gamma) region segments. The analysis of the TCR gamma gene rearrangements may help to differentiate reactive lymphoproliferations from T-cell NHLs. The aim of this study was to reveal the usefulness of polymerase chain reaction (PCR) analysis of the TCR gamma gene rearrangement in the diagnosis of T-cell NHLs using native and formol-paraffin embedded tissues. The PCR amplification of the TCR gamma gene was performed by the V gamma specific sense and J gamma specific antisense primer pairs. The PCR products were evaluated by polyacrilamide gel electrophoresis containing ethidium bromide. The PCR analysis of the TCR gamma gene rearrangements has been performed in 95 lymphoproliferative disorders. The PCR analysis of the TCR gamma gene showed clonal gene rearrangement in 22 cases out of the 39 T-cell NHLs and in one case out of the 12 O-cell anaplastic large cell lymphoma but no clonal rearrangements were detected in any of the 15 reactive lymphoproliferations or 13 B-cell NHLs. Thus, clonal TCR gamma gene rearrangements was detected by PCR in 58.2% of T-cell NHLs but no clonal TCR gamma gene rearrangements were shown in any of reactive lymphoproliferations of B-cell NHLs. These studied showed that the PCR amplification of the TCR gamma gene can be a powerful tool in the diagnosis of T-cell NHLs.

[Screening methods in genetic diagnosis of hereditary protein C deficiency]. / Szürö módszerek alkalmazása a herediter protein C hiány genetikai diagnosztikájában.

Genomic analysis and detailed blood coagulation examinations of 22 family members of 18 families with repeatedly low protein C activity have been performed. Blood coagulation examinations: INR, fibrinogen, plasminogen, alpha-2-antiplasmin, lupus anticoagulant, APC resistance test, protein C activity and antigen, protein S activity and antithrombin activity. Genetic examinations: the presence of FII G20210A alle and FV:Q506 Leiden mutation were examined and for the mutation screening in the protein C gene combination of polymerase chain reaction (PCR) with denaturing gradient gelelectrophoresis (DGGE) or with single-strand conformation polymorphism (SSCP) analysis has been performed. The amplified DNA fragments with aberrant migration during DGGE and SSCP analysis were sequenced. Nine family members of seven families were identified carrying mutations in the protein C gene: one nonsense mutation in exon VII (Arg 157-Stop), two types of missense mutations in four patients in exon IXA (230 Arg-Lys, 254 Thr-Ile, the latter is a new mutation, Protein C Pécs), one missense mutation in two patients in exon IXB (325 Val-Ala), one missense mutation in exon IXC (359 Asp-Asn) and a rare frameshift deletion in exon IXC (364 Met-Trp, 378 Stop). Nine families were evaluated carrying no mutation in their protein C gene, but other genetic or blood coagulation disturbances have been identified, eight of them had borderline decrease in their protein C activity (60-70%). The presence of FV:Q506 mutation could be diagnosed in eight families (in 3 cases homozygous, in 5 cases heterozygous form), among them combination of the defects could be proved in three of the eight families: FV:Q506 Leiden mutation with antiphospholipoid antibodies in 2 families and the presence of Leiden mutation with prothrombin gene mutation in 1 family. Protein S deficiency in combination with prothrombin gene mutation has been identified in 1 family. There were 2 families where no genetic or blood coagulation alterations could be detected in the background of the repeatedly low protein C activity. Large deletions or insertions which are not detectable by our screening methods could not be excluded in these families and therefore sequencing of the total protein C gene had been performed with negative results. According to the literature and our experience the screening methods that were administered in this study are suitable for the detection of mutations in the protein C gene.

[Positron emission tomography ia an effective tool in modern oncology]. / A pozitronemissziós tomográfia a korszerü onkológiai ellátás hatékony eszköze.

A total of 399 positron emission tomography (PET) examinations were carried out with a GE 4096 Plus PET scanner during the past 5 years on patients referred to the National Institute of Oncology in Budapest. The majority (n = 316) of these investigations were performed with the use of [18F]-fluorodezoxyglucose (FDG) to map the glucose metabolism; [11C]-methionine PET was indicated in 79 cases to detect protein transport and metabolism. The perfusion tracer [15O]-butanol was applied in only 4 cases to answer certain oncology-related, differential diagnostic questions. The oncological examinations were related to primary diagnostics, staging/restaging and therapy monitoring. In the staging/restaging and therapy monitoring of known tumours, conclusive results were achieved in 81-82% of the cases by using either FDG or [11C]-methionine as tracer. The concordant numerical data indicated that the PET investigation provides a definite answer to the question of the presence or absence of viable tumour tissue, with similar effectivity in any of the above indications, no matter whether FDG or [11C]-methionine is used. The search for occult primary tumours was the most frequent indication within the primary diagnostics: 10 (37%) primaries were localized by using FDG PET in the 27 investigated cases. This is a remarkably high value, especially in view of the failure of all the conventional diagnostic procedures carried out prior to the PET investigations. Application of PET may be indicated in all cases when the ultimate question is a non-invasive estimation of viable tumorous tissue.

[Incidence of factor V G1681A (Leiden) mutation in samplings from the Hungarian population]. / A faktor V G1691A (Leiden) mutáció gyakorisága magyar népességmintákban.

Thromboembolic disorders affect 0.1% of the adult population. Two main groups of the underlying predisposition factors can be identified: environmental factors (e.g. dietary habits, physical activity, surgical interventions, pregnancy etc.) and several genetic predispositions (e.g. inherited anticoagulant defects). After the discovery of the genetic mutation of factor V, called Leiden mutation, it turned out, that this mutation is responsible for the development of resistance to activated protein C in majority of the cases. The importance of the Leiden mutation is further emphasised by population based investigations, which makes it the most frequent thrombosis risk factor known today. In our study we have identified 43 heterozygotes and 3 homozygotes with Leiden mutation in total of 665 samples. The 6.47% heterozigocy is in the range of earlier reports from Europe. The homozygote/heterozygote distribution deviated from the value predicted by the Hardy-Weinberg law.

[Current principles of diagnosis and treatment of chronic lymphocytic B-cell leukemia]. / A B-sejtes krónikus lymphocytás leukaemia diagnosztikájának és kezelésének modern elvei.

Chronic lymphocytic leukaemia is the most frequent form of malignant hematological diseases in the Western countries, it comprises 30-40% of all the leukaemias and it manifests itself between 60-65 years of age. Clinical features are caused in 93% of the cases by the accumulation and proliferation of immunologically incompetent, anergic, long lived, CD5 positive B-lymphocytes, expressing monoclonal IgM or IgD immunglobulin, in the bone marrow, the peripheral blood, the lymphoid and in other organs. In the etiology genetic basis is highly supposed, whereas affect of toxic agents and radiation exposure can be neglected. The prognosis of patients is variable and is determined by the clinical stage and the proliferative activity of the disease. Treatment is indicated in intermediate and high-risk clinical stages only with signs of disease activation on the basis of individual patient's risk. As first line treatment, Chlorambucil is indicated in high doses. Results achieved by combined chemotherapy are generally not superior compared to high-dose Chlorambucil treatment. For patients who developed resistance to alkilating agents purin analogues are recommended. Out of them the most favorable results had been accumulated with Fludarabine as second line treatment. For minority of the cases hemopoetic stem cell transplantation as the only curative therapeutic measure is being introduced in an increasing number. This review gives an account of the recent advances in the diagnosis and therapy of the disease.

[Study of the Leiden mutation (factor VQ 506), the most frequent cause of thrombophilia, in 116 thrombosis patients]. / A familiáris thrombophilia leggyakoribb okának, a Leiden mutációnak (faktor V. Q506) vizsgálata 116 thrombosisos betegben.

The incidence of Leiden mutation was examined by PCR method in 116 thrombophilic patients in random fashion. Mean age at the first thrombotic episode was 30.97 years. 90 patients had positive family history for thrombosis, 67 had more than one thrombotic episodes. APC resistance with laboratory test was found in 51 cases (44%). F V Leiden mutation was proven in 44 patients (38%). 10 being homozygous and 34 heterozygous out of them.

[Molecular biologic study and the factor VIII gene in hemophilia A]. / A VIII. faktor génjének molekuláris biológiai vizsgálata haemophilia A megbetegedésben.

Results of inversion in the intron 22 region of the VIII factor gene studied by Southern blot are presented. Inversion was found in 20 of 46 patients. In 14 cases (70%) distal and in 6 cases (30%) proximal type of inversion was detected. The significance of the positive result in genetic counseling and in presymptomatic diagnosis of Haemophilia A is emphasized.