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1.
Eur J Surg Oncol ; 40(11): 1445-52, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25107687

ABSTRACT

INTRODUCTION: Hereditary Non-Polyposis Colorectal Cancer is an inherited disease with deleterious germline mutations in the DNA mismatch repair genes causing the development of colon cancer and other malignancies. This is the first study in Hungary screening the population of our colorectal cancer patients in order to identify the prevalence of the disease. METHODS: In families who met the Modified Amsterdam and Bethesda Criteria the removed tumor tissue was first examined by immunohistochemistry and microsatellite instability analysis. Those cases which showed high microsatellite instability underwent DNA sequencing and multiple ligation dependent probe amplification. RESULTS: Of the 1576 patients with colorectal cancer underwent screening for the modified Amsterdam and Bethesda criteria, 69 (4.4%) and 166 (10.5%) fulfilled the criteria respectively. 15 patients (31%) of the Amsterdam positive group and 19 patients from the Bethesda positive (18.1%) were MSI-H. There were 8 pathogenic mutations identified in 9 families (60%) in the Amsterdam positive group. 5 mutations were found in 5 families (26%) in the Bethesda positive group. 12 pathogenic mutations were identified, two of these are newly identified, and being published first in this work. These two new mutations were located on MLH1 (g.31276_35231del) and MSH2 (c.969_970delTC) genes. CONCLUSION: The prevalence of the mutations in the MLH1 and MSH2 genes was almost equal in our Hungarian colorectal cancer patients. One mutation in the MLH1 gene (c.143A > C; p.Q48P) was identified in three different families. Whether this mutation is the most frequent in the Hungarian population is still unidentified and warrant further investigation.


Subject(s)
Adaptor Proteins, Signal Transducing/genetics , Colorectal Neoplasms, Hereditary Nonpolyposis/genetics , Germ-Line Mutation/genetics , MutS Homolog 2 Protein/genetics , Nuclear Proteins/genetics , Adult , Aged , Cohort Studies , DNA Mismatch Repair , Female , Humans , Hungary , Male , Microsatellite Instability , Middle Aged , MutL Protein Homolog 1 , Retrospective Studies , Sequence Analysis, DNA , White People
3.
Osteoporos Int ; 24(1): 179-86, 2013 Jan.
Article in English | MEDLINE | ID: mdl-22422303

ABSTRACT

UNLABELLED: This study reports a high prevalence of hypovitaminosis D and low bone mineral density (BMD) in a healthy Hungarian male cohort over 50 years of age. Men with 25-hydroxyvitamin D levels of <75 nmol/L had a significantly higher 10-year hip and major osteoporotic fracture probability using the country-specific fracture risk assessment (FRAX) algorithm. INTRODUCTION: The aim of this study is to characterize the prevalence and seasonal variation of hypovitaminosis D and its relationship to bone metabolism in healthy Hungarian men over 50 years of age. METHODS: We determined levels of 25-hydroxyvitamin D (25-OH-D), PTH, osteocalcin (OC), C-terminal telopeptides of type-I collagen (CTX-I), procollagen type 1 amino-terminal propeptide (PINP), BMD at L1-L4 (LS) and femur neck (FN), daily dietary calcium intake, and the 10-year probability of hip fracture and a major osteoporotic fracture using the country-specific FRAX algorithm in 206 randomly selected ambulatory men. RESULTS: The mean (range) age of the volunteers was 60 (51-81) years. The prevalence of hypovitaminosis D (25-OH-D, <75 nmol/L) was 52.9%. The prevalence of low (T-score < -1.0) BMD at the FN and LS was 45% and 35.4%, respectively. The mean (range) FRAX hip fracture and FRAX major osteoporotic fracture was 0.8% (0-9.4%) and 3.8% (1.7-16%), respectively. On comparing the vitamin D sufficient to the insufficient group, there was a statistically significant difference between the FRAX hip fracture and FRAX major osteoporotic fracture indexes. There was significant seasonal variation in the vitamin D levels; the lowest levels were measured in winter and the highest in summer. CONCLUSIONS: A high prevalence of hypovitaminosis D and low BMD were observed in the studied Hungarian male population. This is the first study reporting higher 10-year hip and major osteoporotic fracture probability using the country-specific FRAX algorithm in individuals with hypovitaminosis D.


Subject(s)
Osteoporosis/epidemiology , Vitamin D Deficiency/epidemiology , Aged , Aged, 80 and over , Algorithms , Bone Density/physiology , Cross-Sectional Studies , Femur Neck/physiopathology , Humans , Hungary/epidemiology , Lumbar Vertebrae/physiopathology , Male , Middle Aged , Osteoporosis/etiology , Osteoporosis/physiopathology , Osteoporotic Fractures/epidemiology , Osteoporotic Fractures/etiology , Osteoporotic Fractures/physiopathology , Prevalence , Risk Assessment/methods , Seasons , Vitamin D/analogs & derivatives , Vitamin D/blood , Vitamin D Deficiency/complications , Vitamin D Deficiency/physiopathology
4.
Eur J Surg Oncol ; 35(10): 1128-30, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19423266

ABSTRACT

Hereditary Nonpolyposis Colorectal Carcinoma (HNPCC) is the most frequent inherited disease which can lead to the development of tumors in the colon and other locations. Its genetic basis is related to the germline mutation of the Mismatch Repair (MMR) genes. Muir-Torre syndrome is considered one of the subtypes of this disease, in which the HNPCC tumor spectrum is frequently associated with sebaceous carcinoma of the skin or keratoacanthoma. A 57 years old male patient is presented with a mucinous carcinoma of the caecum and an adenocarcinoma of the pancreas head. A malignant sebaceous carcinoma was removed from his left neck area. His family history was significant for two cases of colon carcinoma, two cases of stomach cancer and a case of metacron endometrial and skin tumor as well. Both the colon carcinoma and the skin tumor proved to be microsatellite unstable. An Arg>Pro switch missense mutation was found in codon 265 of the hMLH1 gene. This error was found in 4 other members of his family. The detected genetic alteration was considered pathogenic and was not published yet in English literature. The significance of this particular case is the rare tumor association in a patient with Muir-Torre syndrome (MTS). In cases of sebaceous skin lesions, evaluation of family history is of utmost importance in the early detection of HNPCC and in the follow up care of family members with the particular mutation.


Subject(s)
Adaptor Proteins, Signal Transducing/genetics , Muir-Torre Syndrome/genetics , Mutation, Missense , Neoplasm Proteins/genetics , Nuclear Proteins/genetics , Adenocarcinoma, Mucinous/genetics , Adenocarcinoma, Mucinous/pathology , Cecal Neoplasms/genetics , Cecal Neoplasms/pathology , Family Health , Humans , Male , Middle Aged , Muir-Torre Syndrome/pathology , MutL Protein Homolog 1 , MutL Proteins , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/pathology , Pedigree
5.
Ann Rheum Dis ; 64(10): 1485-9, 2005 Oct.
Article in English | MEDLINE | ID: mdl-15829578

ABSTRACT

OBJECTIVE: To investigate the intracellular and soluble cytokine levels and T cell subsets in peripheral blood of patients with active and inactive polymyositis and dermatomyositis. METHODS: The frequencies of T and B lymphocytes, T helper (Th), and T cytotoxic (Tc) cells and of interferon gamma (IFNgamma), interleukin (IL)4, and IL10 expression of CD4+ or CD8+ cells were determined by flow cytometry. The concentrations of soluble cytokines were measured with commercial enzyme linked immunosorbent assays. RESULTS: In active dermatomyositis there was a decreased percentage of T (CD3+) lymphocytes and Tc (CD8+) lymphocytes, decreased IFNgamma expression of CD4+ and CD8+ cells, but an increase in B and IL4 producing CD4+ lymphocyte frequencies. These prominent changes disappeared in the inactive stage of the disease. In polymyositis no significant change in these lymphocyte subsets or in intracellular cytokine expression could be detected in either the active or the inactive form. The frequency of IL4+/IFNgamma+ Th cells was calculated and a significantly increased Th2/Th1 frequency was found in active dermatomyositis, and a decreased frequency in inactive dermatomyositis, compared with the control population. CONCLUSIONS: There appears to be a difference between polymyositis and dermatomyositis in the level of peripheral blood lymphocytes and their intracellular cytokine content. These findings provide further evidence for a difference in the pathogenesis of polymyositis and dermatomyositis.


Subject(s)
Cytokines/biosynthesis , Polymyositis/immunology , T-Lymphocyte Subsets/immunology , Adolescent , Adult , Aged , Cytokines/blood , Dermatomyositis/immunology , Female , Flow Cytometry/methods , Humans , Immunophenotyping , Interferon-gamma/biosynthesis , Interleukin-4/biosynthesis , Lymphocyte Activation , Lymphocyte Count , Male , Middle Aged , T-Lymphocytes, Cytotoxic/immunology , T-Lymphocytes, Helper-Inducer/immunology , Th1 Cells/immunology , Th2 Cells/immunology
6.
Br J Dermatol ; 147(6): 1135-41, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12452862

ABSTRACT

BACKGROUND: A number of studies exist demonstrating the increased expression of type 2 cytokines and decreased capacity to produce interferon-gamma (IFN-gamma) in peripheral blood mononuclear cells (PBMCs) of patients with atopic dermatitis (AD). OBJECTIVES: To clarify the results of recent studies concerning the role of interleukin (IL)-4 and IL-13 in PBMCs of AD patients, we analysed the activation status of lymphocyte subpopulations. METHODS: We measured the intracellular expression and serum levels of certain type 1 and type 2 cytokines, using cell surface and intracellular cytokine staining, flow cytometry and enzyme-linked immunosorbent assay techniques. RESULTS: The frequency of IL-10 and IL-13 producing CD4+ and CD8+ T cells was significantly higher in patients with AD, while the frequency of IFN-gamma secreting helper and cytotoxic T cells was significantly lower in patients with AD than in control subjects. The serum levels of IL-10 and IL-13 were also significantly increased. There were no significant differences observed between the experimental groups in the frequency of IL-4 producing CD4+ and CD8+ cells. CONCLUSIONS: This study demonstrates a type 2 cytokine production in the CD4+ and CD8+ T cells of AD patients, which is characterized by an elevated IL-13, but not by IL-4 secretion, and by an increased level of the immunoregulatory IL-10, which can contribute to a decrease in IFN-gamma expression.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Dermatitis, Atopic/immunology , Interleukins/blood , Adolescent , Adult , Child , Female , Flow Cytometry , Humans , Immunoglobulin E/blood , Immunoglobulin G/blood , Interleukin-10/blood , Interleukin-13/blood , Interleukin-4/blood , Lymphocyte Activation , Lymphocyte Subsets/immunology , Male
7.
Cytometry ; 45(2): 115-23, 2001 Oct 01.
Article in English | MEDLINE | ID: mdl-11590623

ABSTRACT

BACKGROUND: CD14, the major lipopolysaccharide (LPS)-binding protein of myeloid cells, is found as a soluble molecule in human serum. Recent data describe the presence of elevated soluble CD14 (sCD14) concentration in various disorders, confirming disease activity. A novel, easy, and rapid flow cytometric assay was developed to measure sCD14 levels in serum. METHODS: The assay is based on the competition between membrane-expressed CD14 of isolated monocytes from healthy volunteers and sCD14 in the sample sera for binding to anti-CD14 monoclonal antibodies (mAb; 26ic or 60bca). The amount of cell-associated mAb is determined with a fluorescein isothiocyanate (FITC)-labeled anti-mouse conjugate and flow cytometry. The fluorescence signal is inversely proportional with the amount of serum sCD14. Using dilutions of a standard serum, the concentration of sCD14 in the samples is calculated and compared with results obtained by a commercial sCD14 enzyme-linked immunosorbent assay (ELISA). RESULTS: After optimization, the assay showed log-log linearity of 122.1-984.7 ng/ml sCD14 using mAb 26ic and 29.5-246.2 ng/ml sCD14 using mAb 60bca. It revealed similar results as the ELISA (mAb 26ic: r = 0.88, mAb 60bca: r = 0.92) and provided significantly elevated sCD14 levels in systemic lupus erythematosus patients compared with controls (26ic: 2,213 versus 1,676 ng/ml, P < 0.002; 60bca: 2,625 versus 1,907 ng/ml, P < 0.0002). Receiver operating characteristic curve analysis suggested a reasonable diagnostic efficacy of sCD14 quantification in this autoimmune disease. CONCLUSIONS: The method is easy, rapid, sensitive, and can be used in the follow-up of patients suffering from sepsis or chronic inflammatory disorders.


Subject(s)
Flow Cytometry/methods , Lipopolysaccharide Receptors/blood , Adult , Cell Separation , Enzyme-Linked Immunosorbent Assay , Female , Humans , Lupus Erythematosus, Systemic/immunology , Male , Middle Aged , Monocytes/chemistry , ROC Curve , Sensitivity and Specificity
8.
Ann Rheum Dis ; 60(4): 380-4, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11247869

ABSTRACT

OBJECTIVE: To compare the activity of calcineurin in the peripheral blood mononuclear cells (PBMC) of 32 patients with systemic lupus erythematosus (SLE) and 35 healthy controls. METHODS: The activity of calcineurin was assayed in the supernatants of sonicated mononuclear cells. RESULTS: There was no significant difference in the calcineurin activity of patients with SLE not taking glucocorticosteroids (GCS) compared with the healthy controls. On the other hand, the activity of calcineurin was reduced in patients with SLE taking GCS, correlating negatively with the dose of GCS. The stimulation of PBMC by phorbol ester and calcium ionophore decreased the calcineurin activity both in patients with SLE and in healthy controls. GCS could also reduce calcineurin activity in the mononuclear cells of healthy subjects in vitro. CONCLUSIONS: In patients with SLE the decrease in the calcineurin activity of PBMC depended on the dose of GCS used for treatment, and it was not a disease specific alteration. The higher the dose of GCS, the greater the inhibition of calcineurin activity. The reduction of calcineurin activity is a new element in the immunosuppressive effects of GCS during the treatment of patients with SLE.


Subject(s)
Calcineurin/drug effects , Glucocorticoids/therapeutic use , Leukocytes, Mononuclear/drug effects , Lupus Erythematosus, Systemic/drug therapy , Methylprednisolone/therapeutic use , Adolescent , Adult , Aged , Calcineurin/blood , Case-Control Studies , Cells, Cultured , Dose-Response Relationship, Drug , Female , Humans , Ionophores/pharmacology , Leukocytes, Mononuclear/metabolism , Lupus Erythematosus, Systemic/blood , Male , Middle Aged , Tetradecanoylphorbol Acetate/pharmacology
9.
Orv Hetil ; 142(42): 2303-7, 2001 Oct 21.
Article in Hungarian | MEDLINE | ID: mdl-11760647

ABSTRACT

Inflammatory Bowel Diseases are a group of diseases with chronic inflammation of the gastrointestinal tract, but without proven etiology. Immunologic, environmental, infective and genetic factors equally can play role in their development. Antibodies to an oligomannose epitope of the Saccharomyces cerevisiae demonstrated in 60-70% of the patients with Crohn's disease. The origin and the clinicopathological role are not clarified. It is important that there are no surveys with patients suffering in gluten sensitive enteropathy in the literature. As there are no ASCA survey in Hungary, the aim of this study was to determine the prevalence of the ASCA. The authors examined at their patients the ASCA's occurrence and compared with the clinical picture of the Crohn's disease. The results supported the theory that ASCA positivity correlates with small intestines' Crohn's disease and in these cases both the IgG and IgA type antibodies proved. The antibodies in the sera at the analyzed ASCA positive cases prove a systemic immune response against Saccharomyces cerevisiae and the authors suggest the end of the oral tolerance against the yeast's antigens. The diet restriction (elemental diet, total parenteral nutrition, and fecal diversion) may ameliorate the status of the patients with Crohn's disease. It is speculated that the yeast-free diet as a part of the therapy for the ASCA positive patients can be reasonable: moreover the permanent "forbidding" of the yeast can be an acceptable alternative in case of getting well.


Subject(s)
Antibodies/blood , Celiac Disease/immunology , Colitis, Ulcerative/immunology , Crohn Disease/immunology , Saccharomyces cerevisiae/immunology , Adult , Antibodies, Antineutrophil Cytoplasmic/blood , Female , Humans , Hungary/epidemiology , Immunoglobulin A/blood , Immunoglobulin G/blood , Male , Middle Aged , Prevalence
10.
Immunol Lett ; 74(3): 201-5, 2000 Nov 01.
Article in English | MEDLINE | ID: mdl-11064101

ABSTRACT

The objective of this study was to compare the changes in the values of allergen-specific serum IgE levels and zymosan-induced whole blood chemiluminescence (CL) in 41 patients who had exclusively only ragweed allergy in the season of acute symptoms of disease in July, August and September. All patients had allergic rhinitis or rhinoconjunctivitis. Each patient was investigated as a self-control. The ragweed-specific IgE levels were measured by enzyme immunoassay (EIA). The luminol amplified zymosan-induced CL of whole human blood was detected. The allergen-specific serum IgE levels showed slight, but not significant, gradually increasing elevations during the whole season. On the other hand, significant increases were found in the values of the basal but especially in the zymosan-stimulated CL of peripheral blood phagocytes during the acute phase of allergy. Both the basal and the zymosan-induced CL reflected significantly the activated state of the immune system. These observations clearly show that there are well detectable signs of the systemic activation of the immune system in allergic rhinoconjunctivitis beside the local alterations. In addition, the measurements of the basal and zymosan-induced CL of peripheral phagocytes could clearly reflect the clinical state of disease in vitro.


Subject(s)
Allergens/immunology , Conjunctivitis, Allergic/immunology , Immunoglobulin E/blood , Luminescent Measurements , Phagocytes/physiology , Pollen/immunology , Rhinitis, Allergic, Seasonal/immunology , Adult , Antibody Specificity , Conjunctivitis, Allergic/blood , Female , Humans , Immunoglobulin E/immunology , Male , Neutrophils/drug effects , Neutrophils/physiology , Phagocytes/drug effects , Rhinitis, Allergic, Seasonal/blood , Seasons , Time Factors , Zymosan/pharmacology
11.
Immunol Lett ; 74(3): 207-10, 2000 Nov 01.
Article in English | MEDLINE | ID: mdl-11064102

ABSTRACT

Contradictory data are available about the dominance of T-helper 1 (T(H)1), or T-helper 2 (T(H)2) cytokines in systemic lupus erythematosus (SLE). Therefore, intracellular interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) production of T lymphocytes was measured in whole blood of healthy donors and active and inactive SLE patients by flow cytometry. The percentage of IFN-gamma and IL-4 positive cells was low (<1%) in unstimulated samples of the healthy controls, while that of IFN-gamma and IL-4 positive cells in the stimulated cells was 25.2+/-10.6% and 0.6+/-1.5%, respectively. No significant difference was found between SLE patients and healthy controls and between active and inactive patients in these parameters either in the unstimulated or in the stimulated samples. One patient with severe disease had as high as 11.8% IL-4 positive cells and 12.5% IFN-gamma positive cells in the stimulated samples, but after the initiation of intensive corticosteroid and cytostatic therapy, the percentage of IL-4 positive T cells decreased (4.76%) while that of IFN-gamma positive T cells increased (47.91%). We conclude that the intracellular IL-4 and IFN-gamma expression of T lymphocytes does not differ markedly between SLE patients and healthy controls, with the possible exception of severe disease, when marked IL-4 overproduction may exist beside low IFN-gamma production. Furthermore, corticosteroid and cytostatic therapy might normalize this altered IFN-gamma/IL-4 ratio.


Subject(s)
Interferon-gamma/blood , Interleukin-4/blood , Lupus Erythematosus, Systemic/immunology , T-Lymphocyte Subsets/chemistry , Adult , Antibodies, Antinuclear/blood , CD4 Lymphocyte Count , Female , Flow Cytometry , Humans , Lupus Erythematosus, Systemic/blood , Th1 Cells/chemistry , Th2 Cells/chemistry
12.
Cytometry ; 41(4): 279-88, 2000 Dec 01.
Article in English | MEDLINE | ID: mdl-11084613

ABSTRACT

BACKGROUND: CD14 is considered to be the major endotoxin (lipopolysaccharide [LPS]) binding molecule on human monocytes. It initiates cellular response, but its role in the clearance of LPS is not well understood. Under conditions that ensure totally CD14-dependent LPS binding on human monocytes, the internalization mechanisms of LPS and CD14 were studied. METHODS: The uptake and intracellular distribution of fluorescein isothiocyanate (FITC)-LPS and CD14 was determined by flow cytometry, trypan blue quenching, and confocal fluorescence microscopy. Incubation of surface-biotinylated cells with LPS at 37 degrees C or 4 degrees C and subsequent subfractionation was used to further characterize CD14 internalization. The amount of the intracellular CD14 was estimated by CD14 enzyme-linked immunosorbent assay (ELISA). RESULTS: The internalization rate of 10 ng/ml FITC-LPS with 1% human serum was 1% of bound endotoxin per minute, whereas CD14 expression did not decrease at the same time surface. We proved the presence of an intracellular CD14 pool (2.68 x 10(6) molecules per unstimulated monocyte) and could show that internalized FITC-LPS molecules can be found in different intracellular compartments than CD14. Subfractionation of LPS-treated biotinylated monocytes showed no change in biotinylated CD14 in the membrane fraction independently of the incubation temperature (37 degrees C or at 4 degrees C) used, indicating that these CD14 molecules were not taken up by an active process. CONCLUSIONS: These data indicate the presence of a large intracellular CD14 pool in monocytes with a yet unknown function, and suggest that LPS and CD14 molecules can be internalized independently after association on the cell surface.


Subject(s)
Endocytosis , Lipopolysaccharide Receptors/metabolism , Lipopolysaccharides/metabolism , Monocytes/metabolism , Biotinylation , Cell Fractionation , Cells, Cultured , Down-Regulation , Enzyme-Linked Immunosorbent Assay , Flow Cytometry , Fluorescein-5-isothiocyanate , Humans , Lipopolysaccharide Receptors/analysis , Lipopolysaccharides/analysis , Microscopy, Fluorescence , Monocytes/cytology , Monocytes/immunology , Trypan Blue/metabolism
13.
Immunopharmacology ; 48(1): 87-92, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10822092

ABSTRACT

We have investigated the effects of prednisolone sodium succinate (Pss) and cyclosporin A (CSA), applied alone or concurrently, on the release of arachidonic acid (AA) (cytosolic phospholipase A(2) (cPLA(2)) activity) and on the calcineurin (CN) activity of human peripheral blood mononuclear cells (PBMC). The cytotoxic damage to the cells treated by the drugs was estimated by the release of lactate dehydrogenase (LDH). We found that Pss (10(-5) M) could inhibit the CN activity and higher concentrations (10(-4) M) could decrease the cytotoxic damage caused by CSA (10(-4) M) during their combined application. CSA had no specific effect on the release of AA from the cells. In the combined clinical use of glucocorticosteroids (GCS) and CSA, their additive inhibitory effect on CN activity and the protective membrane influence of GCS against the cytotoxicity of CSA may be beneficial.


Subject(s)
Calcineurin Inhibitors , Cyclosporine/pharmacology , Monocytes/drug effects , Prednisolone/pharmacology , Adult , Arachidonic Acid/analysis , Cell Membrane/drug effects , Cyclosporine/antagonists & inhibitors , Drug Interactions , Female , Humans , L-Lactate Dehydrogenase/analysis , Male , Middle Aged , Monocytes/metabolism , Phospholipases A/metabolism , Prednisolone/analogs & derivatives
14.
Ann Hematol ; 79(2): 83-5, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10741920

ABSTRACT

Neutral red is a vital stain known to be accumulated in the lysosomes of neutrophils and monocytes. It is used mainly to identify and detect the activated state of these cells. We have found that the extracellular application of physiological ceramide, i.e., a product of sphingomyelin hydrolysis and a newly defined intracellular second-messenger substance, increased the uptake of neutral red in a dose-dependent manner in human neutrophils, monocytes, and lymphocytes, as demonstrated by flow cytometry. Staurosporine was able to totally block this phenomenon, suggesting the involvement of protein kinase C in the process. These results indicate that the flow-cytometric analysis of ceramide-induced uptake of neutral red can be a new method for the evaluation of lysosome-related activation processes in both phagocytes and lymphocytes.


Subject(s)
Ceramides/pharmacology , Coloring Agents/pharmacokinetics , Lymphocytes/metabolism , Monocytes/metabolism , Neutral Red/pharmacokinetics , Neutrophils/metabolism , Arachidonic Acids/pharmacology , Enzyme Inhibitors/pharmacology , Humans , Phosphatidic Acids/pharmacology , Protein Kinase C/antagonists & inhibitors , Staurosporine/pharmacology
15.
Eur J Clin Invest ; 30(2): 167-79, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10651843

ABSTRACT

An extensive search for the cell membrane targets for lipopolysaccharide (LPS), the major causative agent of Gram-negative septic shock, resulted in the identification of CD14 as the major endotoxin 'receptor'. Besides recognition of LPS, several new aspects of its biological functions have been described recently. In this review the different CD14 forms, their most important biological and biochemical features, signalling properties, cellular and subcellular distribution and association with different diseases are discussed in detail, showing that these molecules posses several unique biological functions and further proving their central role in innate immunity.


Subject(s)
Lipopolysaccharide Receptors/metabolism , Lipopolysaccharides/metabolism , Shock, Septic/immunology , Bone Marrow Cells/immunology , Humans , Immunity, Innate , Models, Biological , Signal Transduction
16.
Clin Exp Immunol ; 118(3): 458-64, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10594568

ABSTRACT

The functional activity and the expression of CR1 on the erythrocytes (E) of patients with SLE were, respectively, determined by measuring the binding to E of either complement-opsonized bovine serum albumin (BSA)-anti-BSA immune complexes (ICC) or specific anti-ECR1 MoAbs. We found that both the functional activity and levels of ECR1 in SLE patients homozygous for ECR1 high density allele were significantly lowered compared with healthy controls having the same allele. Soon after plasmapheresis there was a significant increase in E ICC binding activity, and this increased functional activity was stable. Moreover, plasmapheresis reduced the level of immune complexes demonstrable in the circulation of the patients. The expression of ECR1 determined with several different anti-CR1 MoAbs was also elevated as a consequence of plasmapheresis. This elevation was observed for both MoAb 1B4, which competes for the ICC binding site of ECR1, and for MoAb HB8592, which does not, but the time course for the increase in binding of the two MoAbs was different, in that the epitope recognized by MoAb 1B4 increased more rapidly. The present results, considered in the context of previous findings, suggest that more than one mechanism may be operative with respect to the effects of the plasmapheresis in increasing ECR1 levels defined by different epitopes on the molecule.


Subject(s)
Lupus Erythematosus, Systemic/metabolism , Plasmapheresis , Receptors, Complement 3b/biosynthesis , Receptors, Complement 3b/metabolism , Alleles , Antibodies, Monoclonal/metabolism , Antigen-Antibody Complex/metabolism , Binding Sites/immunology , Binding, Competitive/immunology , Erythrocytes/immunology , Erythrocytes/metabolism , Female , Humans , Ligands , Lupus Erythematosus, Systemic/immunology , Male , Serologic Tests , Serum Albumin, Bovine/immunology
17.
Mol Pharmacol ; 56(4): 824-33, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10496967

ABSTRACT

Peroxynitrite is a cytotoxic oxidant produced during shock, ischemia reperfusion, and inflammation. The cellular events mediating the cytotoxic effect of peroxynitrite include activation of poly(ADP-ribose) synthetase, inhibition of mitochondrial respiration, and activation of caspase-3. The aim of the present study was to investigate the role of intracellular calcium mobilization in the necrotic and apoptotic cell death induced by peroxynitrite. Peroxynitrite, in a low, pathophysiologically relevant concentration (20 microM), induces rapid (1 to 3 min) Ca(2+) mobilization in thymocytes. Inhibition of this early calcium signaling by cell-permeable Ca(2+) chelators [EGTA-acetoxymethyl ester (AM), 1, 2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-AM (BAPTA-AM), 8-amino-2-[(2-amino-5-methylphenoxy)methyl]-6-methoxyquinoline-N,N , N',N'-tetraacetic acid-tetra-AM] abolished cytotoxicity as measured by propidium iodide uptake. Intracellular Ca(2+) chelators also inhibited DNA single-strand breakage and activation of poly(ADP-ribose) synthase (PARS), which is a major mediator of cell necrosis in the current model. Intracellular Ca(2+) chelators also protected PARS-deficient thymocytes from peroxynitrite cytotoxicity, providing evidence for a PARS-independent, Ca(2+)-dependent cytotoxic pathway. Chelation of intracellular Ca(2+) blocked the peroxynitrite-induced decrease of mitochondrial membrane potential, secondary superoxide production, and mitochondrial membrane damage. Peroxynitrite-induced internucleosomal DNA cleavage was increased on BAPTA-AM pretreatment in the wild-type cells but decreased in the PARS-deficient cells. Two other apoptotic parameters (phosphatidylserine exposure and caspase 3 activation) were inhibited by BAPTA-AM in both the wild-type and the PARS-deficient thymocytes. Our findings provide evidence for the pivotal role of an early Ca(2+) signaling in peroxynitrite cytotoxicity.


Subject(s)
Calcium/metabolism , Nitrates/pharmacology , Poly(ADP-ribose) Polymerases/metabolism , Animals , Biological Transport/drug effects , Caspase 3 , Caspases/metabolism , Cell Division/drug effects , Chelating Agents/pharmacology , DNA Damage , DNA Fragmentation/drug effects , Drug Interactions , Egtazic Acid/analogs & derivatives , Egtazic Acid/pharmacology , Enzyme Activation , Female , In Vitro Techniques , Male , Mice , Mitochondria/drug effects , Mitochondria/physiology , Nitrates/toxicity , Oxidants/pharmacology , Phosphatidylserines/metabolism , Thymus Gland/drug effects , Thymus Gland/metabolism
18.
Infect Immun ; 65(6): 2272-7, 1997 Jun.
Article in English | MEDLINE | ID: mdl-9169763

ABSTRACT

We used rough lipopolysaccharide (ReLPS) to construct a fluorescein-labeled LPS (FITC-LPS) with a very high labeling efficiency that bound to isolated human monocytes in a CD14-dependent fashion and that in this respect behaved indistinctively from native LPS. The CD14-dependent binding could be inhibited either by a 1,000-fold excess of unlabeled LPS or by polymyxin B, bactericidal/permeability-increasing protein, cationic protein 18, or soluble CD14. Although this FITC-LPS preparation no longer possessed the ability to prime neutrophils for the production of reactive oxygen species or to stimulate human monocytes to produce tumor necrosis factor, activation of the Limulus amoebocyte lysate cascade was comparable to activation by native LPS. Binding to monocytes was enhanced by human pooled serum (HPS) or LPS-binding protein (LBP) for LPS concentrations up to 100 ng/ml and was completely CD14 dependent. For LPS concentrations exceeding 100 ng/ml, binding was still partially CD14 dependent, but not HPS or LBP dependent. CD14-dependent association of LPS with monocytes was shown to be totally saturable. In conclusion, we found an HPS- or LBP-dependent binding of FITC-LPS to monocytes that was CD14 dependent at up to 100 ng of LPS per ml, and saturation of binding was shown.


Subject(s)
Lipopolysaccharide Receptors/physiology , Lipopolysaccharides/metabolism , Monocytes/metabolism , Animals , Fluorescein-5-isothiocyanate/metabolism , Humans , Mice
19.
J Leukoc Biol ; 61(6): 721-8, 1997 Jun.
Article in English | MEDLINE | ID: mdl-9201263

ABSTRACT

The absolute number of membrane-expressed CD14, the most important endotoxin receptor, on human monocytes and neutrophils shows remarkable variation in the literature. To quantify these numbers two fluorescence methods using fluorescein isothiocyanate (FITC)-labeled monoclonal antibodies (mAb) were applied. A commercially available set of standard beads was used in flow cytometry to quantitate CD14 with eight different mAbs. Independent from their isotype the various mAbs showed minor differences and indicated that peripheral blood monocytes expressed 99,500-134,600 (115,400 +/- 10,600) and neutrophils 1,900-4,400 (3,300 +/- 800) CD14 receptors. There was no significant difference in CD14 expression on leukocytes in unprocessed freshly obtained whole blood and after a Ficoll isolation procedure. However, a short temperature shift resulted in a 1.3- to 1.6-fold up-regulation of CD14. The results obtained with the reference beads were verified with fluorescence Scatchard analysis and spectrofluorometry using mAb 26ic-FITC and showed 109,500 CD14 per monocyte and 6,700 CD14 per neutrophil. For comparison the number of CD14 on the monocytic THP-1 cells and Fc gamma-receptors on human leukocytes were determined using the reference beads and flow cytometry and gave results comparable to published data. Our data indicate that resting human monocytes express roughly 110,000 CD14 molecules on their surface using a simple fluorometric assay. Correct determination of the number of CD14 and other cell surface receptors is of importance in the monitoring of septic patients.


Subject(s)
Lipopolysaccharide Receptors/blood , Monocytes/chemistry , Neutrophils/chemistry , Cell Separation , Erythrocytes/chemistry , Erythrocytes/immunology , Flow Cytometry/methods , Flow Cytometry/statistics & numerical data , Fluorescent Antibody Technique, Direct/methods , Fluorescent Antibody Technique, Direct/statistics & numerical data , Glycophorins/analysis , Humans , Leukemia, Monocytic, Acute/blood , Leukemia, Monocytic, Acute/immunology , Lipopolysaccharide Receptors/immunology , Lipopolysaccharide Receptors/isolation & purification , Membrane Glycoproteins/blood , Membrane Glycoproteins/immunology , Membrane Glycoproteins/isolation & purification , Monocytes/immunology , Neutrophils/immunology , Reagent Kits, Diagnostic , Tumor Cells, Cultured
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