Biomedical subjects

Magdalena Chmiela

Publications and source records attributed to Magdalena Chmiela.

16 recordsLinked to original sources

PubMed2006

Inflammation, immunity, vaccines for Helicobacter infection.

The reason why some individuals remain Helicobacter pylori infected for life but without any symptoms while others develop severe diseases is only partially clarified. Presumably, it depends on multifactorial interactions among host immunologic and physiologic factors, bacterial virulence determinants, and environmental influences modulating the host response. Much effort has been made to identify host genetic factors that may explain an individual susceptibility of the host to H. pylori infection. The identification of H. pylori determinants and the elucidation of their role in modifying the host immune responses were further delineated. The ability of H. pylori to overcome the defense mechanisms on mucosal surfaces as well as to modulate the immune response by interfering with host recognition and transduction systems has been shown. Also new bacterial anti-inflammatory defense systems have been described. Findings in experimental animal models and humans with natural H. pylori infection suggested a double role of regulatory T cells in the course of H. pylori infection: protecting the infected host against excessive gastric inflammation and, in contrast, promoting bacterial colonization.

Animals↗

PubMed2006

Circulating total and active metalloproteinase-9 and tissue inhibitor of metalloproteinases-1 in patients with systemic lupus erythomatosus.

We investigated the serum concentration of total metalloproteinase-9 (tMPP-9), active MMP-9 (aMMP-9), and tissue inhibitor of metalloproteinase-1 (TIMP-1) in a group of 41 patients with SLE and 20 healthy controls. Serum levels of tMMP-9 and TIMP-1 were assessed by an enzyme-linked immunosorbent assay (ELISA) and aMMP-9 by fluorometric assay. The tMMP-9 level was lower in SLE patients (mean 262 ng/mL) than in healthy volunteers (mean 325 ng/mL) (P = .048). Similarly, aMMP-9 level was lower in SLE patients (mean 121 ng/mL) than in control group (mean 169 ng/mL) (P = .0355) and lower in active SLE (mean 54 ng/mL) than in inactive disease (mean 99 ng/mL) (P = .033). TIMP-1 level was also lower in SLE patients (mean 181 ng/mL) than in control group (mean 233 ng/mL) (P = .004). In SLE patients, a positive correlation was found between tMMP-9 and aMMP-9 (rho = 0.568; P = .001). We also found a positive correlation of tMMP-9 and TIMP-1 with VEGF concentrations (rho = 0.450, P = .005 and rho = 0.387; P = .018, resp). tMMP-9, aMMP-9, and TIMP-1 serum levels are lower in SLE patients than in healthy control group.

Adolescent↗

PubMed2006

Tuberculosis bacilli still posing a threat. Polymorphism of genes regulating anti-mycobacterial properties of macrophages.

One third of the earth's population is infected with Mycobacterium tuberculosis, but only 5-10% of the infected individuals will develop active disease over their lifetime. To identify the genes responsible for the variation in the human susceptibility/resistance to tuberculosis (TB) we determined the polymorphisms of three genes crucial for the function of macrophages, in TB patients and healthy controls with no past history of TB. We found no association between the polymorphisms of the NRAMP-INT4, MBL (codons 52, 54, 57) and CD14-159 genes and TB in a Caucasian Polish population. However, we have suggested a possible involvement of CD14 and MBL molecules in the host-mycobacteria interactions on the basis of the significant increase in the serum CD14 and MBL in TB patients compared to healthy controls.

Adolescent↗

PubMed2006

Potential role of LPS in the outcome of Helicobacter pylori related diseases.

In this study we asked a question whether H. pylori LPS with or without LewisXY (Le) determinants as well as LBP (lipopolysaccharide binding protein) and sCD 14 molecules recognizing bacterial LPS may be involved in atherogenesis. Sera from 57 patients with coronary heart disease (CHD), 27 H. pylori infected dyspeptic patients-H.p.(+) and 49 healthy controls (HC) were tested for IgM and IgG to H. pylori LPS expressing LeX (LPS LeX) or LeXY (LPS LeXY) determinants and to a glycine acid extract (GE). Immune complexes (ICs) of Lewis antigens and specific IgM or IgG were also determined. The prevalence of anti-GE IgG and IgA was significantly higher in CHD as compared to HC and the same as in the H.p.(+) group. The highest levels of anti-GE IgG were detected only for CHD group. CHD patients showed upregulation of IgG to LPS LeX and LeXY. In contrast, an upregulation of IgM to such LPSs was found for healthy subjects. The levels ofLeY-anti-LeY IgG ICs were higher in CHD patients than in healthy controls similarly to the levels of LBP. There was no difference in sCD14 concentration between CHD and HC groups. The results obtained in this study indicate that H. pylori infections may be the risk factors of atherosclerosis due to: 1) an enhanced humoral response to H. pylori surface antigens, 2) a host predisposition to respond to Lewis determinants present in H. pylori LPS by IgG, 3) increased levels of serum LBP.

Acute-Phase Proteins↗

PubMed2005

Principle of a new immunoassay based on electrophoretic mobility of poly(styrene/alpha-tert-butoxy-omega-vinylbenzyl-polyglycidol) microspheres: application for the determination of helicobacter pylori IgG in blood serum.

The principle of a novel latex diagnostic test for the determination of antibodies against Helicobacter pylori in blood sera is described. The test is based on the measurement of the electrophoretic mobility of the microspheres with immobilized H. pylori antigens. The electrophoretic mobility of these microspheres depends on the concentration of the antibodies against H. pylori in suspending medium. Particles with hydrophilic polyglycidol in the surface layer were used for the test. The microspheres were obtained by an emulsifier-free emulsion copolymerization of styrene and alpha-tert-butoxy-omega-vinylbenzyl-polyglycidol macromonomer (D(n) = 220 nm, diameter polydispersity factor D(w)//D(n) = 1.02). Activation of polyglycidol hydroxyl groups with cyanuric chloride allowed for covalent immobilization of H. pylori antigens. The fraction of H. pylori not specifically adsorbed onto the microspheres was negligible. Changes of the electrophoretic mobility of the microspheres with the surface concentration of the covalently immobilized H. pylori antigens Gamma = (1.6 +/- 0.3) . 10(-3) g m(-2) were suitable for the detection of the antibodies in the sera of patients with titer in the range (determined by the indirect ELISA test) from 1:500 to 1:32 000.

Antigens↗

PubMed2005

Occurrence of serum class G immunoglobulins interacting with specific antigens of Helicobacter pylori in patients with unstable coronary artery disease and in symptomless individuals.

An impact of Helicobacter pylori on the process of atherogenesis may be related to the intensity of humoral response against selected specific antigens of this bacteria. We performed serological studies in which the recognition of 7 selected antigens was possible. The investigated group consisted of 56 patients hospitalized due to unstable angina pectoris. The control group consisted of 29 symptomless volunteers. The levels of class G serum immunoglobulins interacting with glycine extract (GE) of H. pylori antigens were assessed by ELISA test in both groups. The same sera were tested by the Milenia blot H. pylori IgG system. In this assessment the presence of IgG antibodies interacting with antigens of molecular weight of 120, 87, 64, 35, 30, 26, and 20 kDa was estimated separately for every listed antigen. The results revealed significant differences between investigated groups in the prevalence of anti-GE IgG (unstable angina - 100% vs. controls - 60%) and in the level of such antibodies expressed as total optical density units--OD450 (6.1 +/- 3.0 vs. 3.4 +/- 3.0 respectively, p<0.05). However, anti-GE IgG detected in the sera of patients as well as controls reacted with similar frequency with selected H. pylori antigens: highly specific (120, 87, 64, 30 kDa) and specific (35, 26, and 20 kDa). We conclude, that although H. pylori infection is so common and mainly associated with gastroduodenal symptoms, it is also recognized by serological methods with high prevalence in patients with coronary artery disease, and less frequently in symptomless individuals. The humoral response against H. pylori in class G immunoglobulins in patients with unstable angina is characterized by higher levels of anti-H. pylori IgG but not by the higher prevalence of serum IgG interactions with the highly specific and specific H. pylori antigens. Such infection could be considered as a cofactor for atherogenesis by inducing strong humoral response against surface antigens of this bacteria.

Adult↗

PubMed2004

[Level of mannose-binding lectin (MBL) in patients with tuberculosis].

Mannose-binding lectin (MBL) constitutes an important element in innate immune response against invading microorganisms. On the other hand, it has also been suggested that MBL, due their opsonic activity, might facilitate the uptake of certain intracellular pathogens. The aim of this study was to investigate whether MBL plays a role in tuberculosis. MBL serum concentration was determined in 68 patients with tuberculosis (TB), 30 patients with non-TB lung diseases and in 64 healthy controls. Serum MBL level was tested by an ELISA test with S. cerevisiae mannan-coated microtiter plates. Generally, TB patients had significantly higher MBL levels than both control groups, and in TB group percentage of individuals with highest MBL level was significantly higher (39.7%). These results indicate that high levels of MBL may be involved in the pathogenesis of tuberculosis and to be a relative disadvantage in mycobacterial infection.

Adult↗

PubMed2004

[IgG anti-multiantigen sonicate of Mycobacterium tuberculosis (Mts) measured by ELISA-Mts].

Laboratory diagnosis of tuberculosis (TB) is often difficult. In recent years the detection of TB by serologic means has been the subject of a number of investigations. We studied the diagnostic utility of enzyme-linked immunosorbent assay in pulmonary tuberculosis. Two serological tests, commercial Pathozyme-Myco IgG (Omega Diagn.), and self-prepared ELISA-Mts using mycobacteria sonicate were evaluated simultaneously with 132 serum samples. Frequency and level of anti-mycobacterial IgG were compared in sera from 68 patients with TB and in sera from 64 healthy volunteers. The sensitivities of the tests with sera from TB patients were, respectively 55.9% and 70.6%. The specificities of these tests were respectively 98.5% and 84.4%. By combining two tests, a maximum sensitivity of 76.5% was obtained with reciprocal drops in specificity to 82.8%. Despite that, it has been suggested that combinations of different antigens were attempted in order to improve the diagnostic yield.

Antibodies, Bacterial↗

PubMed2003

Helicobacter pylori lipopolysaccharide in the IL-2 milieu activates lymphocytes from dyspeptic children.

In this study, we assessed the proliferative response of peripheral blood mononuclear leukocytes (PBML) from 33 children/young adolescents with chronic dyspepsia, to H. pylori LPS in the presence and absence of IL-2 as a T cell growth factor. A rapid urease test (RUT) and a presence of Helicobacter-like organisms (HLO) in the biopsy specimens allowed us to distinguish RUT/HLO-positive (17/33) and -negative (16/33) patients. H. pylori LPS alone induced a proliferation of PBML from 4 out of 33 dyspeptic patients. IL-2 increased the prevalence of the response to LPS to 59% and 74% of RUT/HLO-positive and -negative patients, respectively. PBML from RUT/HLO-positive patients responded significantly less intensively to H. pylori LPS in the presence of IL-2, to IL-2 alone and to H. pylori LPS+IL-2. However, there was no difference in PHA-driven proliferation of PBML from the patients of those two groups. A negative correlation between the responsiveness to H. pylori LPS of PBML and occurrence of type B inflammation in gastric mucosa was demonstrated. The results suggest a contribution of H. pylori LPS to an outcome of H. pylori infection. It is speculated that H. pylori LPS by an activation of immunocompetent cells may reduce gastric inflammation, decrease bacterial load and prolong H. pylori infection.

Adolescent↗

PubMed2003

A link between Helicobacter pylori and/or Chlamydia spp. infections and atherosclerosis.

Antibodies to Helicobacter pylori, Chlamydia spp. and Mycobacterium bovis were determined in patients with coronary heart disease, H. pylori-related dyspepsia, and tuberculosis, and healthy controls. Enzyme-linked immunosorbent assay was conducted with a glycine extract and CagA protein of H. pylori, chlamydial lipopolysaccharide and mycobacterial heat shock protein Hsp65. The prevalence of anti-glycine extract IgG in coronary heart disease patients was higher than in the tuberculosis group and controls, and the same as in dyspeptic patients. Anti-chlamydial IgG were more prevalent in the coronary heart disease group than in healthy subjects. There was no difference in the prevalence of anti-CagA IgG in the coronary heart disease group and controls or anti-Hsp65 IgG in the patients with coronary heart disease, dyspepsia, tuberculosis, and controls. Anti-glycine extract IgA (like anti-glycine extract IgG) were more prevalent in the coronary heart disease group than in the healthy group. The highest anti-glycine extract IgG/IgA and anti-chlamydial IgG titers were more frequent in coronary heart disease patients as compared with controls. Infections with H. pylori and Chlamydia spp. and enhanced production of antibodies to these pathogens may predispose to human atherosclerosis.

Adult↗

PubMed2003

Serological differentiation of Helicobacter pylori CagA(+) and CagA(-) infections.

Many Helicobacterpylori strains causing gastroduodenal diseases have a cagA gene encoding CagA protein, a virulence factor of these bacteria. Anti-CagA antibodies produced by the majority of people infected with CagA(+) strains can indicate such an infection. In this study, the efficacy of three immunoenzymatic tests for detecting CagA(+) and CagA(-) infections were compared: immunoblot (Milenia ID Blot H. pylori IgG; MB) and ELISA conducted either with a recombinant immunodominant fragment of CagA (rCagA) or the full-length CagA molecule (flCagA). The 13C-urea breath test (13C-UBT) was used for establishing H. pylori status. The serum samples from 157 individuals were used for serodiagnosis. H. pylori CagA(+) infection was detected in H. pylori-infected individuals with similar frequencies by MB (64%) and flCagA-ELISA (60%) and a little less frequently by rCagA-ELISA (53%). There was a high coincidence between the negative results of these three tests for H. pylori-uninfected individuals with no anti-CagA IgG in the serum (96-100%). The results show that rCagA-ELISA and, especially, flCagA-ELISA are easy, inexpensive and useful noninvasive assays for the discrimination of CagA(+) and CagA(-) H. pylori infections in subjects examined by urea breath test.

Adolescent↗

PubMed2002

Characteristics of Staphylococcus aureus, isolated from airways of cystic fibrosis patients, and their small colony variants.

The colonization of respiratory tract by Staphylococcus aureus is a frequent feature of cystic fibrosis (CF), especially in pediatric patients. The formation of small colony variants (SCVs), which produce reduced amounts of alpha-toxin, is one of the proposed ways of staphylococcal accommodation in an intracellular niche. The aim of the present study was to compare some properties of S. aureus SCVs and their parent strains. A site-directed S. aureus hemB mutant and parent strain 8325-4 were included in the study (control pair). Normal and SCV strain pairs from CF patients as well as control strains were tested for the susceptibility to defensins, killing activity of professional phagocytes and adhesion to A549 cell line. Because S. aureus are exposed to many cationic proteins in the host, we challenged a clinical isolate with minimal subinhibitory concentration (subMIC) of protamine and found that hemin and menadione auxotrophic SCVs emerged. SCVs were more resistant than normal strains to protamine but not to dermaseptin. The susceptibility to the bactericidal activity of magainin was the same for normal and SCV strains. The protamine resistance of normal as well as SCVs was strongly enhanced by high salt concentration. The adhesion of some SCVs to A549 cells was higher than adhesion of parental strains. However, the number of adherent bacteria (SCVs) was diminished in the presence of hemin for hemin auxotrophs. The uptake of SCVs by granulocytes was lower than ingestion of normal strains, but SCVs were killed with equal or greater potency. SCVs are adapted to intracellular survival and persistence in the host under certain circumstances. The ability to form a variant subpopulation affords S. aureus additional survival options.

Adolescent↗

PubMed2002

Detection of specific Helicobacter pylori DNA and antigens in stool samples in dyspeptic patients and healthy subjects.

In this study stool samples from dyspeptic patients and healthy subjects were used for detection of specific Helicobacter pylori antigens and DNA by immunoenzymatic test (PPHpSA) and semi-nested PCR (ureA-PCR), respectively. The H. pylori status was estimated by invasive endoscopy-based rapid urease test and histology or noninvasive urea breath test (UBT), and by serology (ELISA, Western blot). The coincidence of H. pylori-negative invasive tests or UBT and negative antigen or DNA stool tests was very high (mean 95%). The PPHpSA results were found positive for 56% and ureA-PCR for 26% of individuals with H. pylori infection confirmed by invasive tests or UBT. The detection of specific H. pylori antigens and especially DNA in feces is not sufficient as a one-step diagnosis of H. pylori infection.

Adolescent↗

PubMed2002

Patients with unstable angina pectoris present increased humoral response against Helicobacter pylori in comparison with patients with aggravated dyspepsia.

A role of autoimmune process and its link with bacterial infections in initiation or aggravation of atherosclerosis symptoms has been suggested. Antigenic mimicry and cross-reactivity of circulating antibodies have been indicated as some major factors in this process. In this study, the prevalence and titers of IgG and IgA antibodies reacting with glycine extract of H. pylori surface antigens were determined immunoenzymatically (ELISA) in the group of patients with unstable ischaemic heart disease and in patients with aggravated dyspepsia. Our results reveal that elevated titers of IgG anti-H. pylori are more typical for cardiac patients and lower prevalence of IgA anti-H. pylori--for those with aggravated dyspepsia. This supports the hypothesis that intensed humoral response in immunoglobulins class G against some bacterial antigens may play a role in the aggravation of symptoms of coronary atherosclerosis.

Adult↗

PubMedDate not supplied

[Assessment of the response of peripheral blood mononuclear leukocytes on Helicobacter pylori infection in children].

In the study the proliferative response of peripheral blood mononuclear leukocytes (PBML) from children with chronic dyspepsia (chr. d) to H.p. antigens was investigated. From 38 children aged 7-18, with chr. d., blood was collected just before upper GI endoscopy. Twenty one patients were found to be H.p. (+). PBML were used for the cultures and were stimulated with heat-killed H.p. G27 bacteria, heated and unheated glycine extract (GE) of H.p. G27 or with H.p. LPS containing Lewis X and Lewis Y determinants, in the presence or absence IL-2. The cell proliferation was estimated on the basis of [3H] - thymidine incorporation. In the cultures, the phenotype of responding cells was determined by an EIA with monoclonal antibody to human CD3, CD4 and CD8. PBML from patients H.p. (-), responded to killed H.p. bacteria and to heated GE more frequently and more intensively than PBML from the H.p.(+). IL-2 enhanced PBML response to these antigens. Unheated GE did not induce PBML proliferation even in the cultures with IL-2. LPS alone induced proliferation of PBML from 3 patients (2 H.p. - and 1 H.p.+). However, in the presence of IL-2, LPS induced proliferation of PBML from 15 patients. In the cultures of PBML stimulated with whole bacteria or heated EG, T cells dominated. In the cultures of PBML from H.p. (+) we found a higher percentage of CD8 cells in comparison with the cultures of PBML from H.p. (-). Data demonstrate a significant variation in the response of PBML from dyspeptic children to H.p. antigens.

Adolescent↗

PubMedDate not supplied

Mannose-binding lectin enhances the attachment and phagocytosis of mycobacteria in vitro.

INTRODUCTION: Phagocytosis is the critical first step in the Mycobacterium (M.) tuberculosis-phagocyte interaction. The process involves microbial ligands and phagocyte surface receptors. It is known that serum mannose-binding lectin (MBL), an innate immune system component, may enhance the uptake of microbes by phagocytic cells and activate the complement system. Since phagocytes are the replicative environment for mycobacteria and, as we described earlier, tuberculosis patients differ from controls in serum MBL level, we asked whether MBL plays a role in promoting M. tuberculosis access to phagocytic cells. MATERIAL/METHODS: To estimate the influence of MBL on the phagocytic process, FITC-labeled Mycobacterium bovis BCG was used as a model bacterium. Neutrophils from healthy individuals were used as phagocytes. Phagocytosis was performed in the presence or absence of recombinant MBL (rMBL; 2 or 20 microg/ml). The activation of complement was determined by dot-blot immune assay with monoclonal antibodies against C5b-C9. RESULTS: We showed that phagocytosis of the bacteria was more intensive in the presence of human rMBL. Both attachment and ingestion of mycobacteria were enhanced when MBL and active complement components (fresh serum) were present in the medium. The dot-blot method showed that the bacteria slightly activated complement by themselves. This effect was enhanced in the phagocyte-bacteria co-cultures containing rMBL. CONCLUSIONS: It is possible that MBL may serve in vivo as one of the factors facilitating the entry of mycobacteria into phagocytes, pathogen spread, and the establishment of infection.

Bacterial Adhesion↗