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J Bartůnková

Publications and source records attributed to J Bartůnková.

At least 19 recordsLinked to original sources
PubMed2006

Exposure to silica and risk of ANCA-associated vasculitis.

BACKGROUND: Exposure to silica dust is considered to be one of etiological factors of antineutrophil cytoplasmic antibodies (ANCA) -associated vasculitis (AAV). METHODS: Subjects exposed to silica dust in Central Bohemia and followed in the Department of Occupational Medicine, Charles University, were selected for study. A group of 86 men exposed to SiO2 for at least 5 years were examined. The association between occupational exposure to silica dust and ANCA positivity is analyzed. RESULTS: The subjects had a mean age of 66.7 years, and mean exposure to silica of 22.3 years. ANCA were detected significantly more frequently in patients group (17.1%; P-ANCA 18x, C-ANCA 3x) than in controls (n = 28, mean age 64.2 years, P-ANCA 1x, i.e., 3.6%). ANCA positivity was found less frequently (7.1%) in the group with history of SiO2 exposure without signs of pronounced silicosis, than in the group with simple (30.3%) or complicated silicosis (36.0%). Odds ratio for ANCA positivity and relative risk estimate in patients with silicosis were highly significant. Among possible predictor factors for ANCA positivity, silicosis and tuberculosis were relevant. No typical AAV was present among the patients. CONCLUSION: Long-term silica exposure may be one of the exogenous factors contributing to ANCA production, however, silica exposure alone, without typical silicosis, was not associated with ANCA positivity.

Adult↗
PubMed2006

[Auto- and alloreactivity of T lymphocytes in myelodysplastic syndrome].

BACKGROUND: Successful therapy with ATG and cyclosporine A in some myelodysplastic syndrome (MDS) patients led us to study the existence of T cells attacking autologous hemopoietic cells. In our study, we attempted to give the direct prove of autoreactive T cells in MDS (autoreactivity analysis). Simultaneously, we analysed the capacity of MDS patients to respond to allogeneic cells from unrelated individuals (alloreactivity analysis). METHODS AND RESULTS: Autoreactive lymphocytes directed against own bone marrow mononuclear cells were analysed using the modification of cell mediated cytotoxic reaction. With one exception we did not confirm the presence of autoreactive T cells among 10 patients examined. Analysis of alloreactivity was performed by means of standard cell mediated cytotoxic reaction and mixed lymphocyte reaction. Surprisingly, the cytotoxic response to allogeneic cells was negative in 11 MDS patients from 16 analysed. When comparing refractory anaemia (RA) and refractory anaemia with ring sideroblasts (RARS) patients, the proportion of negative results was higher in RA (78 %) than in RARS (40 %). In mixed lymphocyte reaction, the response of MDS cells to allogeneic cells of unrelated individual was positive in all tested patients. The preliminary testing of TNF and IFNgamma secretion examined in supernatants of effector cells showed impaired levels of both cytokines in RA and normal levels in RARS in accordance with the findings achieved in alloreactivity analysis. CONCLUSIONS: Autoreactive T cells were not found in MDS patients using our experimental arrangement. Analysis of alloreactivity showed the defect in effector--cytotoxic--phase of cell mediated cytotoxic reaction in the majority of MDS patients. The initial phase of this reaction represented in vitro by mixed lymphocyte reaction gave normal results. The possible reasons of disturbed alloreactivity and its relevance to immunity in MDS are commented in discussion.

Aged↗
PubMed2005

Effects of human plasma proteins on maturation of monocyte-derived dendritic cells.

Dendritic cells (DC) are a promising tool for vaccine therapy due to their unique properties as antigen presenting cells and their ability to prime naïve T cells. Increasing evidence suggests that maturation stage of DC critically influences the fate of the immune response. Generation of monocyte-derived DC for clinically applicable immunotherapy requires the use of well-defined components and stringent culture conditions. An alternative strategy is to use human autologous serum. However, its constituents are not stable and reflect the inflammatory condition of the donor. In order to investigate whether DC properties are influenced by proteins present in the plasma, we matured human monocyte-derived DC with four main plasma components: fibrinogen, fibronectin, plasminogen or C-reactive protein. These purified proteins were added at various concentrations on day 6 after the initial differentiation induced by IL-4 and GM-CSF. The maturation was assessed by phenotyping of maturation-associated marker (CD83) and co-stimulatory molecule CD86 as well as IL-12 production. Functional properties of DC were assessed by endocytic activity and mixed leukocyte culture. Our results indicate that fibrinogen had DC-maturation effect comparable to poly-I:C, TNF-alpha and PGE(2) as a positive control, but it failed to induce IL-12 production. The other plasma proteins had no effect on DC maturation. CRP at high concentration had rather inhibitory effect on DC induced lymphocyte function. We conclude that none of the tested plasma components and acute phase proteins sufficiently induce fully competent mature DC. This finding is important for the preparation of human DC-based vaccines supplemented by autologous sera.

Antigens, CD↗
PubMed2005

[Glucocorticoids and their effect on dendritic cell function].

BACKGROUND: Dendritic cells represent the most effective antigen presenting cells and they are the only cell type capable of initiating the primary immune response. They use several sets of germ-line encoded receptors to differentiate between self and non-self and to detect the presence of danger signals. Danger signals are mainly represented by microbial pathogens but it can be also a necrotic or malignant cell. At various stages of their lifecycle dendritic cells play a key role in maintaining the peripheral tolerance towards self-antigens and in the initiation of an effective immune response. Glucocorticoids have been widely used in the treatment of autoimmune or inflammatory disorders and their immunosuppressive effect has been mainly attributed to the inhibition of lymphocytes functions. METHODS AND RESULTS: In this study, we discuss the effects of glucocorticoids on in vitro generated myeloid dendritic cells and on peripheral blood myeloid and plasmacytoid dendritic cells subsets. CONCLUSIONS: Experimental results point to the profound suppressive effect of glucocorticoids on the antigen presenting functions of dendritic cells and to contribute to better understanding of glucocorticoids-mediated immunosuppressive effect.

Antigen Presentation↗
PubMed2004

Daily oral versus pulse intravenous cyclophosphamide in the therapy of ANCA-associated vasculitis--preliminary single center experience.

The aim of the multicentric randomized trial CYCLOPS is to optimize the treatment of induction of remission in patients with generalized, but not immediately life-threatening ANCA (antineutrophil cytoplasmic antibodies) -associated vasculitis. This will be achieved by reducing the dose of cyclophosphamide by administering it as intermittent pulses. The lower cumulative dose will be very probably accompanied with lower toxicity, whereas the effectivity should be comparable. We have enrolled 28 patients to the study. At present, 18 of them are suitable for evaluation. Our preliminary results show that pulse intermittent administration of cyclophosphamide is safer from the point of morbidity and mortality due to infectious complications. In our hands, this treatment modality does not seem to be less effective than the conventional daily oral cyclophosphamide. However, unambiguous results and treatment recommendations will not be available until the final evaluation of all patients enrolled in the trial.

Administration, Oral↗
PubMed2004

[Immunotherapy--perspectives in therapy of ovarian carcinomas].

OBJECTIVE: To summarise recent knowledge and clinical studies of immunotherapy in the treatment of malignant ovarian epithelial tumors. DESIGN: A literature review. SETTING: Department of Gynecology and Obstetrics, Charles University Prague, 2nd Medical Faculty, University Hospital Motol. Department of Immunology Charles University Prague, 2nd Medical Faculty, University Hospital Motol. ABSTRACT: Combination of surgery and chemotherapy has been the usual standard of therapeutic protocols in ovarian cancer patients. However, this therapy is still not sufficient to eliminate all of the tumour cells. Immunotherapy seems to be an effective approach in combination with surgery and chemotherapy. Immunotherapy includes three types of strategies: cytokine therapy, monoclonal antibody therapy and vaccine therapy, especially vaccines with dendritic cells. All of them are shortly reviewed in this article. IFNalpha, IFNgamma, IL-2, GM-CSF are examples of cytokine therapy. Representatives of monoclonal antibody therapy include trastuzumab (monoclonal antibody against HER-2/neu peptide, MAb B.43.13 (antibody against CA 125), or radiolabeled antibody--pemtumomab (90Yttrium-CC49). Cancer vaccination is used in experiments because it should be effective in presenting tumour cells as foreign cells to effector cells of the immune system. Otherwise, tumour cells are not usually recognised by the immune system as dangerous cells. The efficiency of immunotherapy depends on tumor size and previous therapy. It seems to be effective in potentiation of primary chemotherapy or as a consolidation treatment of minimal residual disease. Immunotherapy is still at the experimental level, but in the future it could be a useful part of protocols for the treatment of ovarian cancer.

Antibodies, Monoclonal↗
PubMed2004

[Primary biliary cirrhosis--specific anti-mitochondrial antibodies].

UNLABELLED: Primary biliary cirrhosis is a chronic liver disease, characterized by the destruction of the epithelial cells of the sublobular, interlobular and septal bile ducts and with the development of cirrhosis. The presence of anti-mitochondrial antibodies against the subunits of mitochondrial 2-oxoacids dehydrogenases is characteristic for patients with primary biliary cirrhosis. The aim of this work was to study the effect of anti-mitochondrial antibodies upon activity of the isolated mitochondrial pyruvate dehydrogenase complex after the incubation with serum from patients with primary biliary cirrhosis. GROUP OF PATIENTS AND METHODS: The activity of the purified bovine pyruvate dehydrogenase complex was studied spectrophotometrically in presence of the serum (1: 1000) from five patients with primary biliary cirrhosis and from ten disease free controls. RESULTS: The activity of the pyruvate dehydrogenase was decreased after incubation with the serum from patients with primary biliary cirrhosis. No similar inhibitory effect was found after incubation with serum from controls. DISCUSSION: The inhibitory effect of the anti-mitochondrial antibodies upon activity of pyruvate dehydrogenase may broaden the spectrum of diagnostic methods in patients with primary biliary cirrhosis. Further investigations are necessary to assess the possible application of this method for monitoring of changes during the course of the disease and for assignation of the disease prognosis.

Adult↗
PubMed2002

Antineutrophil cytoplasmic antibodies, anti-Saccharomyces cerevisiae antibodies, and specific IgE to food allergens in children with inflammatory bowel diseases.

Differential diagnosis between ulcerative colitis (UC) and Crohn's disease (CD) is difficult in the initial phases in pediatric patients with inflammatory bowel diseases (IBD). This study was performed to determine the significance of anti-neutrophil cytoplasmic antibodies (ANCA) and anti-Saccharomyces cerevisiae antibodies (ASCA) in IBD. ANCA were specified with regard to their antigenic specifity, significance to the diagnosis, and correlation of titer with the disease activity. The occurrence of food allergy was questioned, too. Serum samples from 44 children with UC (n = 23) or CD (n = 21) and from disease-control children (coeliac disease, n = 21) were analyzed for IgG ANCA, ANCA target antigens, IgA and IgG ASCA, and IgE to food allergens. Results show that ANCA occur more frequently in UC than in CD and disease-control (74, 24, and 10%, respectively). The presence of ANCA does not reflect disease activity. Antigenic specificity does not differ in any group. IgA-ASCA are found more often in patients with CD (76% versus 17% in UC). The testing for both ANCA and ASCA enabled clear-cut differential diagnosis between UC and CD based on the high specificity (ANCA+ ASCA- 92.5% for UC, ANCA- ASCA+ 93.2% for CD). Specific IgE to food allergens were found in 8.7, 14.3, and 23.8% of patients with UC, CD, and coeliac disease, respectively. We conclude that combined testing of ANCA and ASCA represents a valuable tool in the differential diagnosis between UC and CD in pediatric patients, minimizing invasive diagnostic procedures. Monitoring of ANCA, its specificity, and titer determination does not bring more information. Testing for specific IgE to food allergens may be considered in individual patients.

Adolescent↗
PubMed2001

Biological properties of copolymer of 2-hydroxyethyl methacrylate with sulfopropyl methacrylate.

Interaction of organism with non-toxic implanted polymers depends on the physicochemical properties of the implant surface, which influence the adsorption of bioactive proteins and subsequently adhesion and growth of cells. The synthetic hydrogels are known as poorly adhesive surfaces. In this study we demonstrated the adsorption of albumin, fibrinogen, fibronectin, basic fibroblast growth factor, heparin-binding epidermal growth factor-like growth factor and epidermal growth factor to poly(2-hydroxyethyl methacrylate) (pHEMA) and copolymer of 2-hydroxyethyl methacrylate (HEMA) and potassium salt of 3-sulfopropyl methacrylate (SPMAK). The adhesion and growth of 3T3 cells and human keratinocytes on surface of these polymers was tested without and with pretreatment of polymers with heparin-binding epidermal growth factor-like growth factor. The adhesion of mixture of human granulocytes and monocytes to these surfaces was also tested. The strips of both polymers were subcutaneously and intracerebrally implanted into the rat and the extent of foreign body reaction and brain biocompatibility was evaluated. The results showed the extensive adsorption of basic fibroblast growth factor and heparin-binding epidermal growth factor-like growth factor to copolymer containing SPMAK. However the adhesion (and growth) of cells to this type of copolymers was very low. Preadsorption of human plasma to pHEMA clearly stimulated the leukocyte adhesion in contrary to copolymer containing SPMAK. The extent of foreign-body reaction was significantly higher against the pHEMA compared to tested copolymer p(HEMA-co-SPMAK). In conclusion, the tested copolymer was a poorly adhesive substrate that is only poorly recognized by the non-specific immunity, although the adsorption of basic growth factors to this substrate is highly significant. Both polymers were well tolerated by the brain tissue. The phenotype of surrounding neurons was more close to the control neurons in the brain tissue surrounding the p(HEMA-co-SPMAK) implants.

Journal Article↗
PubMed2000

[Dendritic cells and their use in the therapy of neoplastic diseases].

Dendritic cells (DC) constitute a heterogeneous leukocyte population. Their main function is to capture and process antigens (Ag) and present them to immunocompetent cells. Heterogeneity of DC is reflected at several levels. Myeloid and lymphoid lineage of the DC can be distinguished according to the precursor cell they originate from. The functional differentiation is of the great importance. DC can induce either specific immune reaction or tolerance to certain Ag. It depends upon the microenvironment where the processing of Ag takes place. Phenotypic and functional differences between the subtypes of DC are being extensively investigated for the purpose of their use in the immunotherapy of various diseases, tumors in particular. It appears that one of the causes of the specific anti-tumor immunity failure is the insufficient function of DC in vivo in patients with malignant diseases. Recent technology advances has enabled to generate and cultivate DC in sufficient amounts in vitro from their precursors. Coculturing of DC with the tumor Ag in the presence of cytokine mixture leads to the efficient Ag presentation and to the generation of specific cytotoxic lymphocytes capable of killing tumor cells. Subsequent application of these tumor Ag pulsed DC to the laboratory animals, and to the patients in first clinical studies, can induce regression of malignant disease. On the other side the ability of DC to induce tolerance to certain Ag is the subject of investigation in the field of immunotherapy of hypersensitivity states induced either by outer Ag (allergy) or inner Ag (autoimmune diseases). In this review we summarize source and ontogeny of DC, their morphology, phenotype, function and different ways of their generation in vitro. We emphasize the use of DC in the clinical practice aimed at the immunotherapy of tumor diseases.

Animals↗
PubMed2000

[Secondary hemophagocytic syndrome in a systemic disease].

20 year old man 2 years treated for the seropositive rheumatoid arthritis was admitted for fever accompanied with jaundice, anemia and leukopenia. The underlying disease has been compensated already for long period of time, before his admission only Prednisone (in the dose of 5 mg daily) and Methotrexate (15 mg once a week) was given. His physical examination of admission was without any significant abnormalities, out of the routine laboratory examination the value of leukocytes count was 2.1 x 10(9)/L, erythrocytes 3.7 x 10(12)/L, hemoglobin 95 g/l, hematocrit 0.29, platelets 156 x 10(9)/L. Since admission to hospital the hepatic enzymes ALT, AST, GMT, ALP were about ten times elevated comparing to normal values, the coagulation examination has shown the decrease of Quick test to 55%. With respect to the permanent leukopenia the bone marrow aspiration was taken with the finding of the increase number the RES elements (18.4%) with the signs of hemophagocytosis. The phagocytic reticulum absorbs blood elements erythrocytes, normoblasts, granulocytes, platelets. According to the literature experience we started the combination of the immunosuppressive treatment consisting of corticosteroids and Cyclosporine. Already the day following the application of the high dose of corticosteroids the fever subsided, icterus went away gradually with the normalization of the liver tests. After 20 days of hospitalisation the patient was discharged in good shape. Now, after 4 months the is stabilized on the follow-up treatment of Prednisone a Cyclosporine.

Acute Disease↗
PubMed2000

Cyclosporine A versus methotrexate in the treatment of polymyositis and dermatomyositis.

OBJECTIVE: To determine the effectiveness and tolerance of treatment with cyclosporine A (CyA) or methotrexate (MTX) added to corticosteroids in patients with severe, active polymyositis (PM) and dermatomyositis (DM). PATIENTS AND METHODS: Thirty-six patients (20 with DM, 16 with PM) were enrolled into the study and randomized in MTX (n = 17) and CyA (n = 19) groups. Muscle endurance and functional test (MEFT), clinical assessment (CA), global patient's assessment (GPA), muscle MRI, serum CK, myoglobin, IL-1Ra, and autoantibody status were used to assess the response to therapy after 1, 3, and 6 months. RESULTS: Significant improvement in MEFT, CA, GPA, and muscle MRI was found in both groups. Patients treated with MTX showed insignificantly better response than patients with CyA. CK levels in the MTX group decreased significantly after 1, 3, and 6 months, whereas a significant reduction in the CyA group was first observed after 6 months. IL-1Ra serum levels significantly dropped in the CyA group after two weeks, whereas in the MTX group the significant decrease was first seen after 3 months of treatment. Good correlation was found between each of the clinical parameters (MEFT, CA, and GPA), none of them showed any correlation with CK or IL-1Ra levels. CONCLUSIONS: Administration of MTX or CyA added to corticosteroids was associated with clinical and laboratory improvement. Changes in CK and IL-1Ra levels were not associated with parameters of clinical disease severity measured in this study.

Adrenal Cortex Hormones↗
PubMed2000

Human epidermal Langerhans cells are selectively recognized by galectin-3 but not by galectin-1.

Langerhans cells are dendritic antigen-presenting cells residing predominantly in the epidermis. Since endogenous galactoside-binding lectins with the jelly-roll motif (galectins) are known to trigger cellular responses, including mediator release, we investigated by lectin histochemistry the cells' capacity to bind two common members of this family, i.e. galectin-1 and -3. Actually, surrounding keratinocytes express a high level of galectin-3, and these cells can be considered as donors of this lectin to Langerhans cells. Employing biotinylated galectin-1 and -3, and concomitantly an antibody against CD1a as a second marker, to visualize the position of Langerhans cells in the human epidermis, the expression of galectin-3-reactive glycoligands in contrast to the lack of binding of galectin-1 was observed. Although the functional consequences of this selectivity are unclear, these results reveal an example for differential cellular reactivity towards two related endogenous lectins.

Adult↗
PubMed1999

Coexpression of binding sites for A(B) histo-blood group trisaccharides with galectin-3 and Lag antigen in human Langerhans cells.

Galectin-3 is an immunomodulatory protein with binding capacity for various glycoconjugates including IgE. It has been shown to be produced by epidermal keratinocytes and is present on the surfaces of skin Langerhans cells (LC). Therefore, it may have a role in the pathogenesis of various skin diseases, such as atopic dermatitis. To study the expression of galectin-3 in LC, we used, in addition to specific antibodies, a panel of synthetic, carrier-immobilized, specific oligosaccharides of the A- and B-histo-blood group, which are recognized by this lectin. In the mean time, Birbeck granules were visualized with an anti-Lag antibody. The double labeling experiments showed a remarkable colocalization of signals for Lag antigen (Birbeck granules) and galectin-3, as well as the binding sites for A- and B-histo-blood group trisaccharides. The specificity of the oligosaccharide binding was demonstrated by the lack of binding by Le(c), Le(d) (H blood group antigen), and sLe(x), which are not recognized by galectin-3. These results suggest that galectin-3 is present in Birbeck granules, where it retains reactivity for its glycoligands.

ABO Blood-Group System↗
PubMed1999

Binding sites for carrier-immobilized carbohydrates in the kidney: implication for the pathogenesis of Henoch-Schönlein purpura and/or IgA nephropathy.

BACKGROUND: Henoch-Schönlein purpura is a common vasculitis of childhood affecting the skin, joints, gastrointestinal tract, and kidney. The mesangial deposition of IgA1 is the most critical factor for the prognosis of patients with this disease. The aberrant glycosylation of the IgA1 subclass with the absence of terminally located galactose and presence of only alpha-N-acetylgalactosamine in O-linked oligosaccharides in the hinge region of IgA1 represents a prominent difference from the normal IgA1. These alterations prompt the supposition that the sugar part may guide IgA deposition by recognition of endogenous lectins on the mesangium. METHODS: Owing to the limited knowledge about the expression of carbohydrate-binding sites in the human kidney we initiated the study of this aspect with a class of tools which are suitable to map the lectinome of cells. Employing biotinylated neoglycoconjugates, glycosaminoglycans, and sulphated polysaccharides we monitored the presence of accessible carbohydrate-binding sites in control kidneys represented by tumour-free areas of kidneys with Grawitz tumour and in biopsies from patients with Henoch-Schönlein purpura-associated IgA nephropathy. RESULTS: Using frozen sections, no expression of any tested carbohydrate-binding site(s) was observed in the endothelial and the mesangial cells in glomeruli of the control kidneys as well as in the biopsies from Henoch-Schönlein purpura IgA nephropathic kidneys, in contrast to the tubules. The N-acetylgalactosamine-binding sites were expressed only in the inner layer of Bowman's capsule of 20% of glomeruli of the control kidney from one patient with Grawitz tumour and one biopsy from a patient with Henoch-Schönlein purpura-associated IgA nephropathy. However, the macrophages in the glomeruli of patients with IgA nephropathy and interstitial macrophages from both studied groups, i.e. without and with IgA nephropathy, harbour capacity to recognize carrier-immobilized alpha-N-acetylgalactosamine. Access to this binding site for the neoligand conjugate can be blocked by the monoclonal antibody MEM-18 recognizing CD14 antigen. CONCLUSION: The possibility for a participation of macrophage deposition of IgA1 in mesangium via a lectin mechanism involving this binding capacity warrants further studies.

Acetylgalactosamine↗
PubMed1999

Detection of alpha(beta)-N-acetyl-D-galactosamine-binding sites in kidney--relation to Henoch-Schönlein-associated IgA nephropathy.

Henoch-Schönlein purpura is the most common vasculitis of childhood, accompanied by the deposition of IgA1 immunoglobulins into the glomerular mesangium. The actual molecular mechanism of IgA deposition is not clear, but the altered glycosylation of O-linked oligosaccharides of the hinge region of IgA1 is generally considered as the crucial etiopathogenic factor. The oligosaccharides of this glycoprotein from healthy persons are principally of mucin-type Galbeta1,3GalNAcalpha-O-glycan core structure, frequently sialylated. The patient's IgA hinge region saccharide is an incomplete GalNAcalpha-O-glycan only. This study investigates the presence of binding sites for alpha-GalNAc and beta-GalNAc in frozen sections of kidney with and without nephropathy prompted by the possibility for a lectin mechanism of IgA deposition to mesangium. Neoglycoproteins prepared as conjugates with derivatized alpha- or beta-GalNAc moieties as histochemically crucial ligands and biotinylated bovine serum albumin as a carrier were employed for this purpose. The result of the experiments demonstrated expression of specific and accessible binding sites for both alpha- and beta-GalNAc in tubules but not in glomeruli of kidney samples both with and without nephropathy. These findings imply no involvement of a lectin mechanism of IgA1 binding to mesangium, unless a temporary alteration of accessibility of binding sites for probes in glomeruli occurs or the linkage region beyond the monosaccharide is pivotal for a receptor whose binding site may accommodate a peptide epitope in addition to the O-linked alpha-GalNAc residue.

Acetylgalactosamine↗