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Biomedical subjects

E Puskás

Publications and source records attributed to E Puskás.

At least 19 recordsLinked to original sources
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

[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

Molecular characterization of rifampin-resistant isolates of Mycobacterium tuberculosis from Hungary by DNA sequencing and the line probe assay.

Two regions of rpoB associated with rifampin resistance were sequenced in 29 rifampin-resistant (determined by the proportion method) isolates of Mycobacterium tuberculosis obtained from patients from three counties in Hungary. Of the 29 resistant strains, 27 had a mutation in either the 81-bp region (26 strains) or the N-terminal region (1 strain), while the other 2 strains had no mutations in either region. The locations and frequencies of the mutations differed from those previously reported. The most common mutation in this study, D516V, was found in 38% of the Hungarian strains, a frequency 2 to 10 times higher than that found in studies from other countries. These same 29 isolates were also evaluated with the Inno-LiPA Rif. TB test (LiPA), a reverse hybridization assay for the rapid detection of rifampin resistance. Although LiPA detected the presence of an rpoB mutation in 26 of the resistant isolates, the type of mutation could not be determined in 4 isolates because the mutations present were not among those included on the LiPA strip. In addition, a silent mutation in one of the rifampin-susceptible control strains was interpreted as rifampin resistant by LiPA. These findings demonstrate the importance of validating this rapid molecular test by comparison with DNA sequence results in each geographic location before incorporating the test into routine diagnostic work.

Antitubercular Agents↗
PubMed2000

Beneficial effect of a human monoclonal IgM cryoglobulin on the autoimmune disease of New Zealand black mice.

NZB mice spontaneously develop an autoimmune disease characterized by autoimmune hemolytic anemia, thymic atrophy, lymphoid hyperplasia, and hypergammaglobulinemia. The aim of this study was to examine the hypothesis that cryoglobulins may have an immunoregulatory effect on the autoimmune process. The effect of human monoclonal IgM cryoglobulin preparations (including Cryo13, Cryo14, and Cryo16) isolated from the serum of patients with Waldenström's macroglobulinemia on the autoimmune disease of NZB mice was therefore studied. The effect of cryoglobulin preparations was evaluated on several disease parameters, i.e., survival, severity of anemia, and serum IgM and IgG levels (hypergammaglobulinemia). We found that immunization of NZB mice with Cryo13 at 3 months of age delayed the course of the disease, whereas Cryo14 and Cryo16 were ineffective. Furthermore, the effect of Cryo13 was long lasting. On the other hand, Cryo13 was able to react with 8 of 32 mouse monoclonal natural IgM autoantibodies. In contrast, Cryo14 was able to bind only 2 and Cryo16 none of these mouse monoclonal IgM antibodies. These results indicate that, in this model of autoimmune pathology, the beneficial effect of Cryo13 is mediated by its idiotypic interaction with the murine natural autoantibody network.

Anemia, Hemolytic, Autoimmune↗
PubMed2000

Opposite role of alpha2- and beta-adrenoceptors in the modulation of interleukin-10 production in endotoxaemic mice.

Our aim was to investigate the role of adrenoceptors in the modulation of in vivo interleukin-10 (IL-10) production in lipopolysaccharide (LPS)-treated mice. The effect of different adrenergic drugs on plasma concentration of IL-10 was measured by ELISA 90 min after LPS injection. Our results confirmed the involvement of beta-adrenoceptors since the beta-agonist isoproterenol significantly increased the IL-10 production in response to LPS stimulation, whereas the beta-antagonists propranolol decreased it. In contrast, the alpha2-agonists UK-14304, clonidine and xylazine significantly decreased the IL-10 plasma level, whereas the alpha2-antagonists CH-38083, prazosine and WB-4101 increased it. Our results provide the first in vivo evidence that, in addition to beta-adrenoceptors; alpha-adrenoceptors play also a very important role in the regulation of IL-10 production under endotoxaemic conditions.

Adrenergic alpha-Agonists↗
PubMed2000

Contribution of differently localized alpha 2- and beta-adrenoceptors in the modulation of TNF-alpha and IL-10 production in endotoxemic mice.

Evidence is presented that the immune response to endotoxemia is under tonic control of the sympathetic nervous system. Adrenergic agents may influence the immune response both directly through alpha- and beta-adrenergic receptors expressed by immunologically competent cells and indirectly via alteration of the endogenous NA level by influencing the activity of release-regulating presynaptic alpha 2-adrenoceptors located on the sympathetic nerve terminals. In the immunomodulatory effect of NA/adrenergic drugs, their action on beta-adrenoceptors was dominant, but the considerable role of alpha-adrenoceptors on macrophages was also demonstrated. According to our findings, regulation of the ascending wing of the inflammatory response, that is, TNF-alpha production, is more sensitive to the adrenoceptor effect, whereas modulation of its deregulation by IL-10 production also involves some other determining factors.

Animals↗
PubMed1996

Production of cytokines by rat immunocytoma clonal variants: a new type of intratumor heterogeneity.

A long-term tissue culture line of highly metastatic IR202 immunocytoma of LOU rats, and five of its clones (B4, C2, C4, C5, D3) was examined for their ability to produce cytokines. A combination of cytokine detection bioassays was employed in order to compensate for differences in sensitivity and specificity, and the possibility of inhibitors masking an activity. All the IR202 variants tested were shown to secrete constitutively varying amount of interleukin (IL-6). In addition, most of the cells produce IL-10 and TGF-beta, except clones C4 and C2, respectively. Moreover, supernatants from clone B4, C2, C4, and D3 may contain low levels of soluble IL-1. Membrane-bound IL-1 was found on the surface of B4, C4, and D3 cells. None of the IR202 variants, however, produced IL-2, IL-4, tumor necrosis factor-alpha (TNF-alpha), or LT. These results are consistent with the concept of a new type of intratumor heterogeneity and the ability of immunocytoma tumors to generate different immunoregulatory molecules in tumor-bearing hosts.

Animals↗
PubMed1995

Clinical significance of longitudinal complement measurements in recipients of bone marrow transplant.

Overall activity of classical complement pathway, C3 and C4 levels, level of circulating immune complexes and concentration of serum immunoglobulins were measured in 38 patients transplanted with HLA-identical bone marrow before and after transplantation for at least 4 years. Changes of complement parameters and their association with acute and chronic GVHD and with infections were analysed. A strong association was found between the development of chronic GVHD and hypercomplementaemia measured in 16 long-term survivors. Low pre-transplantation C4 activity was found to predict the development of severe acute GVHD. These findings indicate that longitudinal complement measurements may have clinical value in BMT patients.

Acute Disease↗
PubMed1995

Functional heterogeneity of in vitro selected variants from an IgM-secreting rat immunocytoma.

A long-term tissue culture line of highly metastatic IR202 immunocytoma of LOU rats, and five of its clones (B4, C2, C4, C5, and D3) were established and studied comparatively. All such cells were similar in terms of: (i) light microscopic morphology, (ii) growth rate, (iii) saturation density, (iv) cell cycle progression, and (v) cell surface IgM, major histocompatibility complex (MHC) class I and class II antigen expression, but (vi) showed a non-homogeneous pattern of chromosomal constitution, with both numerical and structural abnormalities detected in variable proportions of the different cell variants. Moreover, IR202 variants exhibited a marked difference in the production of soluble factors which was closely associated with the ability of their supernatants to inhibit mitogen (affinity-purified goat F(ab')2 fragments specific for rat mu-chains (anti-mu antibody), lipopoly saccharide (LPS), or concanavalin A (ConA))-induced proliferation of normal splenic B and/or T lymphocytes. These results are consistent with the concept of intratumor heterogeneity and the ability of immunoglobulin-secreting tumors to induce severe immune dysfunction in host animals and humans.

Animals↗
PubMed1994

[Autoantibodies or immune defense against cholesterol?].

Serological study was made on the lues aspecific positive sera (BAP); The serum reactivity was demonstrated by Kolmer and rapid plasma reagin (RPR) tests. The specificity was verified by treponema immobilization est (TPIT), fluorescent treponemal antibody (FTA-ABS) and treponema haemagglutination (TPHA) tests. The BAP sera were studied by enzyme labelled immunoassay (ELISA) with the isolated antigen components of Kolmer and RPR tests. The previously supposed "cardio-BAP" appeared only about 50 per cent of the sera. Anti-cholesterol antibody was demonstrated in 38 sera of 112 (33.9%) and only one of 50 negative control sera (2%). To the author's knowledge anti-cholesterol antibodies have never been demonstrated before. The authors suppose it is an autoantibody and their new result will give new possibilities to understand and explain the role of cholesterol in the so called "cholesterol diseases". Additional research have to be made to specify the pathological importance and role in the disorders.

Antibodies↗
PubMed1993

Differences in the isoelectric focusing patterns of serum and cerebrospinal fluid transthyretin.

Transthyretin isolated by polyacrylamide gel electrophoresis from human serum and cerebrospinal fluid, dissociated into its subunits, was subjected to isoelectric focusing in polyacrylamide gels containing 8 mole/L urea. The isoelectric focusing multi-component patterns of serum and cerebrospinal fluid transthyretin differ in a characteristic way, having only one main protein zone in common. Double diffusion immunotest and immunoblotting revealed the immunological identity of serum and cerebrospinal fluid transthyretin and of the main components separated by isoelectric focusing. The different isoelectric focusing zones can be consistently explained when they are ascribed to structurally identical transthyretin subunits associated with different ligands specifically occurring in either serum or cerebrospinal fluid. Only the protein zone located at the same pI in serum and cerebrospinal fluid transthyretin patterns may be assigned to ligand-free subunits. Thus, the typical differences in isoelectric focusing patterns may point to different carrier functions of transthyretin in serum and cerebrospinal fluid.

Cerebrospinal Fluid Proteins↗
PubMed1987

Impaired ristocetin aggregation in myeloma due to binding of the aggregating agent by monoclonal protein--presentation of a case.

In a case of severe IgG kappa myeloma with cryoglobulinaemia usual concentrations of epinephrine, collagen, ADP, arachidonic acid, thrombin and ristocetin caused no aggregation of platelets in platelet rich plasma. However, in contrast to other agents ristocetin induced platelet aggregation in higher concentrations. The investigations showed, that the aggregating activity was inhibited by binding of ristocetin to the abnormal protein. Following saturation of the monoclonal protein, the surplus ristocetin caused normal aggregation. This indicates that platelets actually preserved their responsiveness to ristocetin. Possible causes of the phenomenon are discussed.

Aged↗
PubMed1987

An IgM-producing immunocytoma induces large numbers of splenic T lymphocytes with Fc mu receptors.

The expression of Fc mu receptors was investigated using spleen cells from (LOU/M/Wsl X CFY) F1 rats bearing the IR202 tumour, an IgM-producing immunocytoma. It was found that the progressively growing solid tumour was accompanied by an extraordinary expansion of host splenocytes with Fc mu receptors. These cells were nylon-wool non-adherent, Thy-1-positive and sIg-negative: features they have in common with T lymphocytes. In addition, the expansion of Fc mu receptor-bearing T cells in IR202 immunocytoma is correlated to the high level of serum IgM. These observations provide further insight into the mechanism of isotype-specific T-lymphocyte Fc receptor expression, and identify a potential model with which to analyse the immunoregulatory role of Fc mu receptor-bearing T cells.

Animals↗
PubMed1984

Antibody and immunoglobulin levels in aged humans.

IgM and IgG type antibody titers and levels of serum IgG, IgA and IgM were determined in healthy young and aged subjects. The proportion of subjects of low antibacterial agglutinin titers progressively increased during the 7th and 8th decades of life. Anti-streptolysin-O titers were also shifted to the lower values in aged subjects, at least until the 8th decade of life, although subnormal values compared to the young control range were less frequent than in the case of IgM type antibodies. Anti-streptokinase values did not seem affected by age. In contrast to antibody levels, serum IgM was similar or slightly higher in old compared to young subjects. Evidence is presented that the proportion of 7 S IgM drops with aging. Both IgA and IgG levels increased through the 7th, 8th and 9th decades of life. Different class immunoglobulin levels seemed to be considerably correlated and a tendency to correlate was found between IgG type antibody and serum IgG levels. Complex investigations including quantitation of antibodies to extrinsic and intrinsic antigens and serum immunoglobulins are proposed to define the humoral immune status of aged subjects and to understand the causes as well as the diagnostic and prognostic significance of old age 'imbalances'.

Adult↗
PubMed1983

Clinical correlates of circulating immune complex levels in advanced lung cancer. A discrimination analysis.

Sera from 53 patients with unresectable lung cancer were tested for the presence of immune complexes by 12 assays. 5 assays (EA rosette inhibition, ADCC inhibition, platelet aggregation, IgG and C3 concentrations in PEG precipitates) could discriminate cancer patients from healthy subjects with over 80% reliability. On the basis of 3 assays (EA-I, ADCC-I and PEG-C3) a function allowing a 100% correct classification could be formulated:--(EA-I)--0.5 (ADCC-I) + 2.4 (PEG-C3) greater than 69.3, i.e., results higher than 69.3 are characteristic for cancer patients and lower than 69.3 for normal subjects. The relationship between the immune complex levels and the average survival time was not altered by sex, age, histology and treatment. None of the immune complex assays or their combination were useful for the estimation of individual life expectation.

Adult↗