Biomedical subjects

K Pálóczi

Publications and source records attributed to K Pálóczi.

At least 19 recordsLinked to original sources

PubMed2001

[Role of molecular genetic investigations in the diagnosis of acute leukemias and in the detection of minimal residual disease].

Chimera gene products, the molecular hallmark of acute leukemias were detected and quantified for diagnostic purposes and for follow up of therapy and characterization of minimal residual disease. In acute lymphoid leukemia mainly the bcr-abl, and in acute myeloid leukemias, depending on the morphological classification, the aml-eto, bcr-abl, pml-rara, plzf-rara, and cbfb-myh chimeras were investigated. The determinations were based on reverse transcriptase-polymerase chain reaction. The results were used in diagnosis of 315 new leukemic patients, and in follow up of 70 ones. In the present paper the usefulness of the applied methods is illustrated by presentation of data of 38 (27, acute myeloid leukemias and 11 acute lymphoid ones) patients out of the 139 treated in the National Institute during the last years.

Acute Disease↗

PubMed2001

Developing an expert system for immunophenotypical diagnosis in immunodeficiency. Age-related reference values of peripheral blood lymphocyte subpopulations in Hungary.

In the process of developing a decision support system based on flow cytometric data for the diagnosis of immunodeficiency, assessment of lymphocyte subpopulations in human peripheral blood provides the key for further analysis. Samples from 273 'healthy' Hungarian subjects were measured between 1998 and 1999. Immunophenotypic data are compared here (unadjusted for gender) by different age groups: I 0-6 years (n=45); II 7-18 years (n=71); III 19-35 years (n=72); IV 36-55 years (n=48); and V 56-99 years (n=37). Two-color flow cytometric analysis was performed using the Becton Dickinson Simultest IMK Plus kit (CD45/CD14, isotype control, CD3/CD19, CD4/CD8, CD3/HLA-DR, CD3/CD16+56). All lymphocyte subpopulations were measured in all blood samples identically. The quality criteria involved at least 95% of total lymphocytes in the analysis gate, homogenous CD45+ lymphocyte population (minimum of 2000 events in the gate, CD45+ >95%). The frequency of B lymphocytes was the highest, significantly, in the youngest Hungarian subjects, but there were no significant changes with age comparing the data of other II-V age groups. On the other hand, some T subpopulations changed with aging; both CD4 and CD8 subsets varied over time including the elevation of the fraction of activated T cells as well as LGL-NK cells. Some of these changes were significant by statistical tests. Interpretation of flow cytometric data is time-consuming and requires human knowledge of an expert laboratory staff. To facilitate the diagnosis of immunodeficiency, a pilot study aiming at the development of a diagnostic algorithm has been initiated. Algorithm nodes compare the frequency of each lymphocyte subpopulations to the generated reference values. This knowledge-based system describes a short summary report as a result of the comparison, and points to some values requiring further human examination to reach a final conclusion. These reference values and the expert system appear to be a recommended basis for comparing and combining results from different laboratories.

Adolescent↗

PubMed2001

[Restricted antibody diversity after bone marrow transplantation--homogeneous immunoglobulins].

After bone marrow transplantation, a prolonged dysregulation of humoral immunity, including restricted electrophoretic heterogeneity of serum immunoglobulins and the appearance of homogeneous immunoglobulin components, can be observed. The current study was undertaken to characterize further and define the posttransplantational incidence of monoclonal and oligoclonal immunoglobulins, as well as the clinical and laboratory correlations of these phenomena. For this purpose, serial serum protein (IgM, IgG, IgA and CRP) quantification, electrophoresis and immunofixation were performed on 29 patients undergoing allogeneic bone marrow transplantation for chronic myeloid leukemia. 23 out of the 29 patients developed transient oligoclonal and/or monoclonal gammopathies that appeared between 20 and 1750 posttransplantational days. No correlation, however, between the development of graft versus host disease, EBV or CMV infections, or any other symptoms and development of homogeneous immunoglobulin components was seen. Therefore, the development of oligoclonal and monoclonal gammopathies after bone marrow transplantation may be an ubiquitous finding reflecting the inadequacy, i.e. oligoclonality of the recovering B-cell system.

Adult↗

PubMed2001

[B-cell content after bone marrow transplantation--molecular basis of the limited antibody diversity].

Despite B-cell counts and serum immunoglobulin levels usually normalized by one year, humoral immunity and the incidence of bacterial infections continue to be abnormal even after years following bone marrow transplantation. This immunodeficiency could be partially caused by B-cell repertoire restriction similar to that observed early in ontogeny. Immune reconstitution after haematopoietic stem cell transplantation really follows many established ontogenetic patterns relating to the appearance of particular membrane markers, immunoglobulin classes and subclasses, and onset of antigen receptor rearrangements. The sequence of events that occur during successful bone marrow transplantation can be regarded as a blueprint for immune reconstitution in other clinical settings as well. However, the repertoire does not resemble a fetal one, because it displays adult-size IgH CDR3s, adult-type immunoglobulin gene utilization and no evidence of bias towards any particular VH-gen family. Therefore, in the description and interpretation of these events, it is important to realize that immune reconstitution does not appear to recapitulate human fetal ontogeny. In terms of B lymphocyte diversity, the inadequacy of the recovering immune system is more likely to be explained by a combination of other factors--such as clonal dominance and the delayed occurrence of somatic hypermutation.

Adult↗

PubMed2001

[Regeneration of the immune system after bone marrow transplantation].

After haematopoietic stem cell transplantation, reconstitution of bone marrow consists of two distinct phenomena, numerical recovery of bone marrow cellular elements on the one hand and functional recovery of cellular interactions on the other. Immune reactivity during the first month postgrafting is extremely low. Cytotoxic and phagocytic functions usually recover by day 100, while more specialized and cooperative functions of T and B cells remain impaired up to one year or more postgrafting. Regeneration of total CD4+ T cell number in adult (and especially in elderly) transplant recipients is severely limited and occurs largely by peripheral expansion of mature CD4+ T cells. While restoration of total CD8+ T cell number is commonly seen in adults, potentially important alterations in the subset composition of CD8+ populations remain. Contracted T cell repertoires for CD4+ and CD8+ T cells are consistently found in adults after T cell regeneration. This suggests that thymic function is frequently limiting in adults and that thymic-independent pathways are insufficient for restoring host immunocompetence. Although there are similarities in immune reconstitution after alllo- and autologous haematopoietic stem cell transplantations, allogeneic transplantation involves graft versus host disease and the use of immunosuppressive therapy to control it, both of which further interfere in the early developmental stages of immune reconstitution.

Animals↗

PubMed2001

Remarkably reduced transplant-related complications by dibromomannitol non-myeloablative conditioning before allogeneic bone marrow transplantation in chronic myeloid leukemia.

A non-myeloablative conditioning protocol containing dibromomannitol (DBM/cytosine arabinoside/cyclophosphamide) has been applied to 36 chronic myeloid leukemia (CML) patients followed by bone marrow transplantation (BMT) from sibling donors. Risk factors include: accelerated phase (10 patients), older age (17 patients over >40 years) and long interval between diagnosis and BMT (27 months on average). Severe mucositis did not occur. Venoocclusive liver disease was absent. Infectious complications were rare. Although grade II-IV acute graft-versus-host disease (GVHD) was present in 9 (25%) cases, there were only 2 serious (III-IV) ones. Chronic GVHD occurred in 25 (69%) cases, preceded by acute GVHD in 9 of the 25 affected patients. Early hematological relapse, 7-29 weeks after BMT, developed in 6 patients (17.6%). No relapse was noted in the completely chimeric patients, however molecular genetic residual disease was observed in 6 patients, in most of them after transient short-term mixed chimeric state. Overall actual survival rate is 83.3% for the 36 cases, and leukemia-free survival is 72.2% for the 34 engrafted patients.

Adolescent↗

PubMed2001

Elevated levels of serum prolactin in patients with advanced multiple myeloma.

BACKGROUND AND OBJECTIVE: The role of prolactin in immunoregulation and normal hemopoiesis is well known. However, prolactin also seems to be involved in the pathomechanism of malignancies and autoimmune diseases. Elevated serum prolactin levels were reported in patients with malignant lymphoma, colon and breast carcinoma, systemic lupus erythematosus and rheumatoid arthritis. Recently we demonstrated prolactin immunostaining in bone marrow cells of patients with multiple myeloma. DESIGN AND METHODS: Serum prolactin levels of 56 patients with multiple myeloma, as well as serum beta(2)-microglobulin, and interleukin-6 concentrations were determined in this study. RESULTS: Patients with advanced disease showed a significant increase in serum prolactin concentration, while patients with a clinical stage of I and II, and also control patients had normal values. The concentration of serum beta(2)-microglobulin and interleukin-6 changed in parallel with that of serum prolactin in patients with multiple myeloma. Determining serum prolactin levels several times during the disease process in a given patient clearly showed that the prolactin concentration was increasing during the disease progression. INTERPRETATION AND CONCLUSIONS: Our results indicate a role of prolactin in disease progression in multiple myeloma.

Adult↗

PubMed2001

[Autologous hematopoietic stem cell transplantation in chronic myeloid leukaemia with different clinical stages]

For most chronic myeloid leukaemia patients the option of a potentially curative allogeneic stem cell transplantation is not available because of age or lack of donor. Alternative therapy with interferon-alpha appears to prolong survival but is probably not curative. The aim of the study is to analyse the clinical results of the first Hungarian autologous transplantations in CML. METHODS: Seven patients were treated with ICE-based regimen plus G-CSF with the aim of mobilising and collecting Ph-negative peripheral stem cells in the setting of autologous transplant program. Five patients had CML in first chronic phase and two in accelerated phase. All patients have been previously treated with interferon-alpha. RESULTS: Median value and ranges for harvested mononuclear cells, CD34(+) cells and CFU-GM were: 5.65x10(8)/kg (2.61-11.38), 1.48x10(6)/kg (0.216-3.5) and 3.43x10(4)/kg (0.243-11.6), respectively. Four out of seven autologous grafts have been transplanted. Busulfan conditioning was used in one case and TBI/Cy conditioning in three patients. All patients are alive and well post-transplant being on interferon-alpha therapy. CONCLUSIONS: Based on the clinical advantages of autologous transplantation including long-term chronic phase, achievement of second chronic phase and improved response to interferon-alpha therapy, the procedure can offer an alternative treatment in CML in lack of HLA-identical donor.

Journal Article↗

PubMed2001

[Clinical and immunopathological significance of chimerism in bone marrow and organ transplantations]

Chimerism is an exceptional immunogenetic state, characterized by the survival and collaboration of cell populations originated from two different individuals. The prerequisites to induce chimerism are immunosuppression, myeloablation or severe immunodeficiency of the recipients on one side and donor originated immuno-hematopoietic cells in the graft on the other. Special immunogenetic conditions to establish chimerism are combined with bone marrow transplantation, transfusion and various kinds of solid organ grafting. There are various methods to detect the type of chimera state depending on the immunogenetic differences between the donor and recipient. The chimera state seems to be one of the leading factors to influence the course of the post-transplant period, the frequency and severity of graft-versus-host disease (GVHD), and the rate of relapse. However, the most important contribution of the chimeric state is the development of graft versus leukemia (GVL) effect. A new conditioning protocol (DBM/Ara-C/Cy) for allogeneic BMT in CML patients and its consequence on chimera state and GVL effect is demonstrated.

Journal Article↗

PubMed2001

[Therapy of multiple myeloma]

Multiple myeloma (MM) is a haematological malignancy characterised by the clonal expansion of malignant plasma cells within the bone marrow. It accounts for 10% of all haematological malignant diseases and 1% of all malignancies. The median age of patients at the time of the diagnosis is 70 years. The characteristic clinical features of MM are bone marrow failure, susceptibility to infections, bone pain, pathological bone fractures, hypercalcaemia, and renal failure. Though MM is currently incurable, the important progress in chemotherapy has resulted in an improvement in survival from a median of 7 months in the 1950-ies to about 3 years today. Advances in the diagnosis and in supportive treatment of infections, hypercalcaemia, and renal failure also contributed to the prolongation of survival. For decades, the gold standard of treatment had been oral melphalan alone or in combination with prednisolone. Combination chemotherapy has not improved overall survival (OS), but these regimens have led to the prolongation of event-free survival (EFS) and also to a better quality of life. High-dose chemotherapy with haemopoietic stem cell rescue resulted in a great improvement in EFS as well as OS. For those very few who have an HLA-compatible donor and are under 55, allogeneic bone marrow transplantation offers the best hope of survival but comes at a greatly increased risk of toxicity. There are conflicting data in the literature concerning the role of interferon-alpha; it seems to be able to prolong the duration of the plateau phase. Current treatment is moving towards an approach using sequential therapy. This involves induction therapy proceeding to high-dose chemotherapy with some form of stem-cell rescue. Bisphosphonates reduce hypercalcaemia, bone pain and can inhibit bone destruction. They also possess a direct antitumor activity. The better understanding of the pathomechanism of the disease gives the opportunity of the application of new therapeutic modalities such as antagonising the effect of interleukin-6 (IL-6), or idiotypic vaccination.

Journal Article↗

PubMed2001

Mouse plasmacytoma: an experimental model of human multiple myeloma.

BACKGROUND AND OBJECTIVES: There is no ideal animal model for human multiple myeloma (MM). All the models resemble the human disease in some respect, but none of them fulfils all the criteria of a perfect animal model. EVIDENCE AND INFORMATION SOURCES: The pristane oil (2,6,10,12-tetramethylpentadecane)-induced mouse plasmacytoma (MPC) model is the most widely used and accepted model and has provided the most data on plasmacytomagenesis so far. This model gives the opportunity to study the role of c-myc dysregulations, the mechanisms leading to cytogenetic changes involving Ig genes, the role of chronic inflammatory factors, the role of interleukin-6 (IL-6), insulin-like growth factor-I, prostaglandins, as well as signal transduction pathways in the neoplastic process. Therapeutic agents have been successfully tested. Although MPC growth is usually restricted to the peritoneal environment, intraperitoneal injection of MPC cell suspensions can reproduce the disseminated characteristics of the human disease in recipients. The IL-6 transgene and knockout models are important tools for clarifying the role of IL-6 in the pathogenesis of MM. Transgenic mice and retroviral gene transfer facilitate the study of oncogenes in neoplastic transformation. Spontaneous development of plasmacytomas in C57BL/ KaLwRij aging mice has several advantages, mainly because the disseminated growth, the typical bone lesions and renal involvement resemble, in part, the human disease. Furthermore, this model has already proved useful in studies on the effect of bisphosphonate in the treatment of bone disease in MM. The severe combined immunodeficiency (SCID) mouse model is also very attractive. A disseminated-like disease can be reproduced in this model. Multiple osteolytic bone lesions and bone marrow involvement are generated, and conventional drugs applied in the treatment of human multiple myeloma have proven to be effective. Nevertheless, the immune system of SCID mice basically differs from that of a MM patient. PERSPECTIVES: Taken together, all these models have contributed to our understanding of MM, but demonstrate the opportuness of developing a more appropriate model of the human disease.

Animals↗

PubMed2000

[Immunophenotyping in acute leukemia: detection of minimal residual disease].

Immunophenotyping improves both accuracy and reproducibility of the acute leukaemia classification and is considered particularly useful for identifying poorly differentiated subtypes of acute myeloid leukaemia and lineage association of acute lymphoid leukaemia. Immunological studies of leukaemic blasts has become critical also identifying biphenotypic leukaemias and acute myeloid leukaemia expressing lymphoid associated markers. At present, while the prognostic value of individual antigen expressions is still controversial, the immunologic detection of minimal residual disease seems to be important in monitoring the acute leukaemia patients in remission. In the present study immunophenotyping of bone marrow samples of 42 patients with acute myeloid leukaemia and 13 patients with acute lymphoid leukaemia was analysed. Patients were assessed both before and after treatment by immunophenotyping, cytogenetics and polymerase chain reaction amplification. The immunophenotyping have allowed more sensitive definition of acute leukaemia relapse, but molecular genetic methods are recommended for detection of elimination of residual disease.

Adolescent↗

PubMed2000

Immunological importance of chimerism in transplantation: new conditioning protocol in BMT and the development of chimeric state.

Chimerism is an exceptional immunogenetic state, characterized by the survival and collaboration of cell populations originated from two different individuals. The prerequisits to induce chimerism are immuno-suppression, myeloablation, or severe immunodeficiency of the recipients on the one side and donor originated immuno-hematopoietic cells in the graft on the other. The pathologic or special immunogenetic conditions to establish chimerism are combined with bone marrow transplantation, transfusion, and various kinds of solid organ grafting. Different types of chimerism are known including complete, mixed and mosaic, or split chimerism. There are various methods used to detect the type of chimera state, depending on the immunogenetic differences between the donor and recipient. The induction of complete or mixed chimerism is first determinated by the effect of myeloablative therapy. The chimera state seems to be one of the leading factors to influence the course of the post-transplant period, the frequency and severity of GVHD, and the rate of relapse. However, the most important contribution of the chimeric state is in development of graft versus leukemia effect. A new conditioning protocol (DBM/Ara-C/Cy) for allogeneic BMT in CML patients and its consequence on chimera state and GVL effect is demonstrated.

Antineoplastic Agents, Alkylating↗

PubMed1998

[Use of studies on genome polymorphism in follow up after allogenic bone marrow transplantation].

The study of structures polymorphic in size found in the human genom (the VNTR loci) enables us to differentiate two individuals or--after bone marrow transplantation--to detect the simultaneous presence of two genoms in patients' blood or marrow. The existence of mixed chimerism may influence the therapy. The authors have screened 54 patients, transplanted in their Institute, and their donors by determination of four polymorphic loci. Informative marker was found in 43 cases. The bone marrow transplantation immunotherapy of 29 patients could be followed over 2-36 months. To increase the sensitivity of the polymerase chain reaction method used, the authors introduced the blotting/hybridization steps using isotop labeled repetitive sequences. The results are presented in comparison with literature data.

Bone Marrow Transplantation↗

PubMed1998

[A new radiation-free conditioning in bone marrow transplantation and dibromo-mannitol therapy in chronic myeloid leukemia].

A new, radiation-free, conditioning protocol, containing the original Hungarian mitobronitol (DBM) (DBM/ cytosine arabinoside/cyclosphosphamide) has been applied to 36 chronic myeloid leukemia (CML) patients followed by bone marrow transplantation (BMT) from HLA identical sibling donors between 1990-1997. In spite of some prognostically disadvantageous factors (half of them were above 40 years, 10 out of 36 patients were in accelerated phase, the disease history was longer than 2 years in average) the overall survival (30/36) and the leukemia free survival rate (26/36) were in accordance with the best international results. Transplantation-related toxicity was remarkably reduced in comparison to bone marrow transplantation performed by total body irradiation/cyclophosphamide (TBI/Cy) or busulphan/cyclophosphamide (Bu/Cy) conditioning protocols. Acute graft versus host disease was present in lower percentage (9/36) and the number of serious cases was only 2/36. Chronic GVH disease, generally known to be associated with antileukemic effect (GVL), occurred in 25 of cases. Early haematological relapse among the 34 patients with functioning graft occurred in 6 patients which rate is slightly higher than reported after TBI/Cy or Bu/Cy conditioning treatment. There was no relapse among patients transplanted within one year post-diagnosis and patients having CML with accelerated phase. The leukemia free post-transplant period was in association with the chronic GVH disease and full chimeric state.

Adolescent↗

PubMed1998

Histidine decarboxylase in peripheral lymphocytes of healthy individuals and chronic lymphoid leukemia patients.

Histidine decarboxylase (HDC), the only enzyme capable of synthetizing histamine, has been found in many proliferating cells and tissues suggesting a role of histamine in cellular proliferation. In this study expression of HDC and the significance of histamine in the proliferation of peripheral lymphocytes of five healthy persons and six patients with chronic lymphoid leukemia (CLL) was examined. Expression of HDC mRNA and the protein was proved by reverse transcriptase polymerase chain reaction and by immunoblot, respectively. The role of histamine was studied in proliferation assays in the presence of irreversible inhibitor of the HDC (alpha-fluoromethylhistidine--aFMH) and also by competing for the intracellular binding sites of histamine using N,N-diethyl-2, 4-phenylmethyl-phenoxy-ethanamine-HCl (DPPE). By inhibiting the HDC enzyme activity by FMH and blocking the intracellular action of histamine by DPPE, a significant decrease in cell proliferation was observed in mitogen stimulated lymphocytes of healthy donors. In CLL patients the proliferation of leukemic lymphocytes was significantly inhibited by blocking the binding of histamine to intracellular binding sites by DPPE but not by FMH inhibiting only the de novo histamine formation. The observations suggest that HDC has functional relevance in lymphocytes, since mitogen induced lymphocyte proliferation of healthy donors is mainly enhanced by de novo synthesis and subsequent action of intracellular histamine. Alternatively, in constitutively proliferating chronic lymphoid leukemia cells we suggest that the preformed pool but not the de novo synthesized intracellular histamine interferes with cellular proliferation.

Cells, Cultured↗

PubMed1998

Reduction in the frequency of transplant-related complications in patients with chronic myeloid leukemia undergoing BMT preconditioned with a new, non-myeloablative drug combination.

A radiation-free, non-myeloablative, myelosuppressive protocol, containing dibromomannitol and cytosine arabinoside, that remarkably reduced the frequency of transplant-related complications, such as veno-occlusive liver disease (VOLD), severe mucositis, bacterial sepsis, hemorrhagic cystitis, interstitial pneumonitis, has been applied in 19 CML patients, allotransplanted from identical siblings. Five patients were in accelerated phase. Acute GVHD developed in two patients and chronic GVHD occurred in 66% of patients. Follow-up was 3 to 7 1/2 years. Although only eight patients were under 30 years of age, and only two patients had a history of less than 1 year, the leukemia-free survival was 82%. There were four hematological relapses. The reduction in post-BMT complications has greatly enhanced quality of life. The nurses reported significant reduction of work-load. Savings in eliminating the need for irradiation, parenteral nutrition, and several antibiotics are also remarkable. The remarkable reduction of certain transplant-related complications shows some advantage against busulphan-preconditioning.

Adult↗

PubMed1997

Inhibition of IgE production by epsilon (epsilon) chain-specific antisense oligonucleotides (AOs) studied on human myeloma cell line U266 and peripheral blood mononuclear cells of a patient with hypereosinophilia.

Based on cDNA sequence data epsilon chain-specific antisense oligonucleotides were synthesized and checked on in vitro IgE production. Using peripheral blood cells from a hypereosinophilic patient and a human IgE myeloma cell line, U266, marked reduction of in vitro IgE production measured by PRIST was observed. The effect of epsilon antisenses proved to be isotype specific since IgG production by both peripheral blood cells and a lymphoma cell line, CESS, was not affected. Moreover, the expression of other markers on U266 (interleukin-6 receptor and gp130) were not influenced by epsilon-specific antisense oligonucleotides.

Humans↗