PubMed Health⌕ Search

Biomedical subjects

J Biró

Publications and source records attributed to J Biró.

At least 19 recordsLinked to original sources
PubMed1995

Cytokine networks and corticosteroid receptors.

The role of the inflammatory cytokines on glucocorticosteroid binding (GCSB) and glucocorticosteroid receptor (GR) level was studied. We incubated a B cell line--CESS--, a promonocytic cell line--U937--and a hepatoma cell line--HepG2--in the presence of varying concentrations of IL-1 beta, IL-6 and TNF-alpha for 24 hours. Glucocorticosteroid binding was determined by the method of "whole cell uptake," and characterized by Scatchard analysis. A considerable increase in the glucocorticosteroid binding was induced by all the three cytokines. Northern analysis of the glucocorticoid receptor expression demonstrates that the action of the cytokines is likely not pretranslational. Present data suggest that local imbalance in the ratio of these three cytokines in different pathological cases might influence the glucocorticosteroid sensitivity of the lymphocytes, monocytes and hepatocytes as target cells.

Cells, Cultured↗
PubMed1995

The effect of WSEWS pentapeptide and WSEWS-specific monoclonal antibodies on constitutive and IL-6 induced acute-phase protein production by a human hepatoma cell line, HEPG-2.

Interleukin-6 receptor (IL-6R) is a member of the cytokine receptor superfamily characterised by the obligatory presence of WSXWS (Trp-Ser-X-Trp-Ser) sequence motif near the transmembrane domain. To more clearly understand the role of this motif, we treated the HepG2 hepatoma cell line with synthetic WSEWS peptide (E is glutamic acid) and checked the spontaneous and IL-6-induced production of acute-phase protein fibrinogen and C1-inhibitor (C1-INH). The peptide revealed a definitely stimulatory effect both on the constitutive synthesis of C1-INH and on the IL-6-induced fibrinogen synthesis of HepG2 cells. Monoclonal antibody specific for WSEWS pentapeptide was stimulatory for the spontaneous secretion of both fibrinogen and C1-INH. However, the IL-6-induced elevations of these acute-phase proteins were oppositely regulated, since the anti-WSEWS monoclonal antibody was inhibitory on the production of fibrinogen induced by IL-6 but strongly augmented the IL-6 induced production of C1-INH. Our study indicates that the WSEWS motif is critical in the effect of IL-6 on the acute-phase protein production influencing either the ligand binding by the WSEWS-containing receptor molecule or the signal transduction.

Acute-Phase Proteins↗
PubMed1995

Enhancement of interleukin-6 production by fibrinogen degradation product D in human peripheral monocytes and perfused murine liver.

The effect of fibrinogen degradation products D and E (FDP-D, FDP-E) on IL-6 production in perfused mouse livers and peripheral monocytes is studied. Similarly to bacterial endotoxin FDP-D is highly potent to augment the IL-6 production measured in perfused mouse livers, while FDP-E is not stimulatory. FDP-D but not FDP-E is able to stimulate the in vitro IL-6 production of human peripheral monocytes, as well. Plasmin alone is almost ineffective on IL-6 production both in perfused livers and monocytes. Our findings suggest a direct positive feedback circuit, among fibrinogen, FDP and IL-6.

Adult↗
PubMed1994

Separate regulation of a membrane protein, gp130, present in receptor complex specific for interleukin-6 and other functionally related cytokines.

In addition to specific ligand binding elements, receptor assembly for interleukin(IL)-6, oncostatin-M, leukaemia inhibitory factor, ciliary neurotrophic factor and IL-11 includes an additional unit, gp130. This molecule is a transmembrane glycoprotein of 130 kDa. In this paper, reviewing molecular, biochemical and functional data on gp130, we describe the dissimilar action of IL-3 on the expression of the binding unit of the IL-6 receptor and that of gp130. According to FACS studies, resting basophils express only IL-6 receptors and no gp130 molecules on the plasma membranes. After incubation with IL-3, the surface appearance and de novo transcription of gp130 was shown by FACS and mRNA polymerase chain reaction analysis.

Antigens, CD↗
PubMed1993

Modulation of glucocorticosteroid binding in human lymphoid, monocytoid and hepatoma cell lines by inflammatory cytokines interleukin (IL)-1 beta, IL-6 and tumour necrosis factor (TNF)-alpha.

In order to elucidate the role of the inflammatory cytokines in regulating glucocorticosteroid binding (GCSB) and glucocorticosteroid receptor (GR) level we incubated a B-cell line (CESS), a promonocytic cell line (U937) and a hepatoma cell line (HepG2) in the presence of varying concentrations of IL-1 beta, IL-6 and TNF-alpha for 24 h. Glucocorticosteroid binding was determined by the method of 'whole cell uptake', and the cellular appearance of the glucocorticosteroid receptor was detected by immunocytochemistry. A rise in the glucocorticosteroid binding was induced by all three cytokines. The increase in level of glucocorticosteroid receptors in the cells shown by immunocytochemistry was much more pronounced. However, antagonistic effects were demonstrated by both methods between IL-6 and TNF-alpha, and between IL-1 beta and TNF-alpha when they were applied simultaneously, in U937. Present data suggest that local imbalance in the ratio of these three cytokines in different pathological cases might influence the glucocorticosteroid sensitivity of the lymphocytes, monocytes and hepatocytes as target cells.

Animals↗
PubMed1992

[Molecular genetic, laboratory and clinical study of serum amyloid P].

Studying the gene polymorphism of serum amyloid P a common constituent of amyloid deposits two restriction fragment length polymorphism patterns were found among Hungarian rheumatoid arthritis (RA), juvenile rheumatoid arthritis (JRA), systemic lupus erythematosus (SLE) patients and healthy controls. Although no direct connection between DNA polymorphism and the frequency of amyloidosis in three patient groups was found, a marked predominance of the heterozygosity in all studied groups has been described. Authors found close correlation between the serum levels of SAP and CRP in juvenile rheumatoid arthritis, but failed to find the same correlation in SLE and healthy controls. Moreover, the serum level of CRP of heterozygous patients were significantly higher than that of homozygous patients within the juvenile rheumatoid arthritis patient groups.

Amyloid↗
PubMed1992

Histamine modulates the interleukin-6-regulated acute phase protein synthesis in cultured murine hepatocytes.

Murine hepatocytes cultured in the presence of human recombinant interleukin-6 (IL-6) show increased synthesis of fibrinogen and complement component C3 by the addition of histamine. No similar effect was achieved when murine hepatocytes were treated with histamine alone or with histamine and interleukin-1 alpha together. Using histamine-1 (H1) and H2 receptor antagonists a prevalence of histamine H1 receptor in the enhancement of IL-6-induced effect is suggested.

Animals↗
PubMed1980

The influence of influenza vaccinations on human peripheral blood lymphocytes relating to aging.

Twenty healthy, aged more than 60 years were compared to 20 healthy young volunteers less than 40 years following influenza vaccinations. 0.5 ml, 10 U. of killed influenza vaccine Hong Kong B/873 was repeatedly given intramuscularly. Blood was collected before the vaccination, 6 days, respectively 6 weeks after vaccinations. The purified venous blood lymphocytes were examined by immunohistological and sheep erythrocyte rosette-forming methods. The absolute number of T and B lymphocyes was counted. It has been found that increase of IgG-bearing cells was higher in young persons, than in the elderly both in the first and in the revaccination. The absolute number of IgM-bearing lymphocytes increased in the aged after influenza vaccinations. The vaccine had no significant effect on the absolute number of IgA-bearing lymphocytes. The absolute number of T lymphocytes participating in the immune reaction showed a transitory increase solely in young persons. Experiments aiming to demonstrate the reduced activation of B lymphocytes in the elderly with the influenza vaccinations. It can be concluded, that the proliferation ability of the immunoglobulin-bearing B cells and T cells is reduced due to old age.

Adult↗
PubMed1979

Electronmicroscopical and immunoelectronmicroscopical examination of the lymphocytes of young and old people after influenza vaccination.

Authors examined the lymphocytes of young and old individuals before, 6 days and 6 weeks after influenza vaccination. Vaccination was carried out with killed Influenza B/Hong-Kong virus. Electronmicroscopic structure of the lymphocytes and membrane bound surface IgG and IgM were studied. Membrane bound surface IgG and IgM were seen on the small lymphocytes and on the membrane of the medium-sized lymphocytes in young and aged individuals before and after vaccination. In both age groups intracytoplasmic tubuloreticular structures were seen in the lymphocytes. These findings were not age dependent alterations. Age dependent changes could be detected on the mitochondria of the lymphoid cells. The mitochondrial crysts in aged individuals disappeared and were replaced by myelin-like forms or by faint density substance. The mitochondrial changes were present before vaccination and after vaccination in non labelled, presumably T lymphocytes. The injury of the mitochondrium can influence the function and the proliferative capacity of the cells.

Age Factors↗
PubMed1979

Alterations of two parameters of cellular immunity in the aged men.

There were two parameters of cellular immunity in 46 old and 34 adult (control) individuals investigated. These reactions were delayed type hypersensitivity of the skin and the in vitro leukocyte migration inhibition test. PPD was used as antigen for both reactions. According to our investigations there was no correlation between them neither in the aged nor in the control group. But the statistical analysis of data revealed a significant difference between skin responses of aged and control groups. In spite of this we consider cellular immunity unaltered in old men, because there was no difference in migration inhibition between aged and adult men and according to our earlier experiments in guinea pigs this test is much more reliable than skin response.

Adolescent↗
PubMed1978

Effect of the depletion on brain noradrenaline on the plasma FSH and growth hormone levels in ovariectomized rats.

The electrolytic lesion of locus coeruleus reduced the hypothalamic noradrenaline (NE) content to 28% of the control values and resulted in a marked decrease of the plasma FSH level in ovariectomized rats before puberty. The local microinjection of 6-OH-dopamine into the locus coeruleus led to a reduction in the hypothalamic NE content to 21% of the control level and induced a decrease of the compensatory ovarian hypertrophy and that of the plasma FSH level. The electrolytic lesion of the locus coeruleus or the 6-OH-dopamine treatment failed to influence the plasma growth hormone (GH) level. The observations support the hypothesis that ventral noradrenergic projection is involved in controlling the pituitary FSH secretion.

Animals↗
PubMed1978

Immuno-electronmicroscopic studies after influenza vaccination of young and old individuals.

Authors examined the lymphocytes of young and old individuals after influenza vaccination. They stated that membrane bound surface IgG and IgM were detectable on the lymphocytes and occasionally on lymphoblasts in both the old and young age groups. In both age-groups intracytoplasmic tubulo-reticular structures (TRS) were seen in the lymphocytes and lymphoblasts. In young individuals TRS was present in the peroxidase positive cells, in the contrary in old persons TRS was never found in cells with surface immunoglobulins. In the TRS themselves peroxidase positive IgG and IgM could be detected.

Adult↗
PubMed1978

Autoantibodies in aged individuals.

Authors determined in 282 individuals autoantibodies in 132 T and B lymphozytes. Theirs results were as follows: 1. The frequency of the presence of autoantibodies increases with age. 2. In the presence of autoantibodies the absolute T and B lymphocyte counts of aged persons markedly decrease; the absolute T and B lymphozyte counts of young adult people do not change by existing autoantibodies. 3. There is a significant difference between the absolute T cell counts of aged and young adult age groups, both age-groups having autoantibodies. 4. Comparing the frequency of occurence of autoantibodies in aged healthy persons and in aged ones with cardiovascular changes and being in the habit of smoking and consuming alcohole, respectively, a significant difference could be demonstrated; in the latter group the frequency was much higher.

Age Factors↗
PubMed1978

Age-related change of the absolute number of IgG-, and IgM-bearing B-lymphocytes and T-lymphocytes in human peripheral blood following influenza vaccination.

The absolute number of IgG-, and IgM-bearing B lymphocytes and of T lymphocytes was determined in the peripheral blood of 12 old (over 60 years) and 11 young (20 to 40 years) healthy persons before vaccination and 6 days and 6 weeks, respectively after vaccination. It has been found that as opposed to an approximately fivefold increase of IgG bearing cells in young persons, the increase did hardly reach double of the original value in old individuals. The absolute number of T lymphocytes participating in the immune reaction showed a transitory increase in young persons, while a gradual decrease has been observed in old individuals. In healthy elderly persons the administration of 10 U Honkong 5/72-B killed influenza virus as in vivo antigen stimulus resulted in a reduced proliferation of IgG carrier lymphocytes participating in antibody production.

Adult↗
PubMed1977

Nuclear RNA content and synthesis in anterior pituitary in intact, castrated and androgen sterilized rats.

The content and uridine incorporation into nuclear RNA of anterior pituitary gland was studied in vitro in intact, castrated and neonatally testosterone treated rats of both sexes. In female rats a higher RNA content and a lower uridine incorporation rate could be observed than in males. The castration resulted in a marked increase of RNA content and uridine incorporation in male rats. Ovariectomy was followed by a decrease of RNA content which was accompanied by an increase of incorporation rate. Estradiol administration produced a biphasic change of RNA content and uridine incorporation in ovariectomized rats. From these findings a repressive action of estrogens on the nuclear RNA synthesis may be suggested. Neonatal testosterone treatment resulted in alterations of RNA synthesis which could be observed in both sexes.

Animals↗