bluuebunny/crossref_metadata_2025_split huggingface dataset:
Autoantibodies in Patients with Rheumatoid Arthritis
Authors: Astrinidou‐Vakaloudi A. , Diamanti I. , Xytsas S. , Xatzidimitriou D. , Georgakopoulou E. 
Published: August 2010

Aim:  The aim of this study is to examine the diagnostic value of autoanitbodies in patients suffering from rheumatoid arthritis. We evaluated the presence of the following autoantibodies: rheumatoid factor (RF), antinuclear antibodies (ANAs), antibodies against cadiolipin (a‐CL) and antibodies against cyclic citrullinated peptide (anti‐CCP).Methods:  We studied the presence of RF, ANA, a‐CL and anti‐CCP in 40 patients with rheumatoid arthritis. Rheumatoid factor was measured using nephelometric method, while ANAs were examined by indirect immunofluorescence technique using Hep‐2 cells as substrate. Sera that reacted at 1/80 dilution were classified as ANA positive. Positive sera were studied up to 1/1280 dilution. A‐CL and anti‐CCP were measured by enzyme‐linked immunosorbent assay.Results:  RF was positive in 30 patients (75%), ANA in 15 (37%), a‐CL in 10 (25%) and anti‐CCP in 36 (90%). Predominant pattern of nuclear staining of ANA‐positive sera was homogenous and speckled type. ANA titres were particularly low; most patients (6) had ANA titre equal to 1/80, and five patients had a titre of 1/160, while only four out of 40 had an ANA titre of 1/320.Conclusions:  Autoimmune disorders such as RA are characterized by various autoantibodies that usually are not specific, as they are present in many other diseases. However, RF and especially anti‐CCP are very often and show higher specificity for RA, being useful diagnostic serological markers. On the other hand, ANA and a‐CL are less common in RA paitents; they may be useful in terms of prognosis and treatment, but they always should be evaluated in correlation with the clinical features and the rest of the laboratory findings of each patient.
The Effects of Hyperbaric Exposure on Human Peripheral Blood Mononuclear Cells, with Special Emphasis on Natural Killer Cell Cytotoxicity and Subsets
Authors: Krog J. , Jepsen C. F. , Tønnesen E. , Parner E. , Hokland M. 
Published: August 2010

Materials and methods:  As an experimental physiological stress model, we examined the effects of hyperbaric exposure on peripheral blood mononuclear cells (PBMCs) obtained from venous blood drawn from eight divers during a simulated heliox saturation dive. Eight persons working in normobar atmosphere outside the pressurized chamber served as control donors. The spontaneous cytotoxicity of the PBMCs was estimated in a 4 h 51Cr‐release assay using k562 as NK‐sensitive target cells. The PBMCs were characterized, using 4‐colour flow cytometry, with special emphasis on the NK‐cell subsets. The data were statistically analysed using a multivariate regression model (Stata 8.2). P values <0.05 was considered statistically significant.Results:  The estimated cytotoxicity increased significantly in both the group of divers and control donors during the dive (pdivers < 0.01 and pcontrols < 0.01). Although the cytotoxicity increased relatively more (P < 0.01) in the group of divers compared to the group of control donors between day 1 and 2.Discussion:  The increased cytotoxicity of PBMC estimated in the group of divers indicate that parts of the cellular immune system are affected during the extreme physiological conditions induced during the initial phase of the presented experimental hyperbaric setup. The increase in cytotoxicity observed in the group of control donors could hypothetically reflect the stress level in persons working outside the pressurized chamber during the dive.
Differential Effects of Interleukin‐12 and Interleukin‐10 on Superantigen‐Induced Expression of Cutaneous Lymphocyte‐Associated Antigen and αEβ7 Integrin (CD103) by CD8+ T cells
Authors: Sigmundsdóttir H. , Johnston A. , Gudjónsson J. E. , Valdimarsson H. 
Published: August 2010

The interaction with adhesion molecules expressed by vascular endothelium is the first step in lymphocyte infiltration into tissues. At both cutaneous and mucosal sites interleukin‐10 (IL‐10), IL‐12 and transforming growth factor (TGF)‐β are important regulators of chronic inflammatory disease, where cutaneous lymphocyte‐associated antigen (CLA) and αE integrin (CD103) may be expressed. Unlike CLA, CD103 is not believed to play a role in tissue‐specific homing but may help to retain T cells within epithelial layers. We have previously shown that IL‐12 alone can together with an unknown cofactor increase the expression of CLA. Stimulation with streptococcal pyrogenic exotoxin C (SpeC) increased the expression of CD103 by CD8+ but not CD4+ T cells. While IL‐12 increased superantigen‐stimulated expression of CLA, this cytokine strongly inhibited the CD103 expression, and a combination of IL‐12 and TGF‐β completely abrogated the induced CD103 expression. Conversely, IL‐10 suppressed CLA but increased CD103 expression.These findings indicate that, in addition to suppressing the development of Th1‐mediated inflammatory responses, IL‐10 may also inhibit the migration of CD8+ T cells into the skin while IL‐12 promotes such migration. Thus, the expression of CLA and CD103 may be antagonistically regulated by IL‐10 and IL‐12, and the balance between these cytokines could influence the T‐cell migration of inflammatory cells into epithelial tissues.
Probiotic Bacteria Induce Regulatory Cytokine Production via Dendritic Cells
Authors: Hvas C. L. , Kelsen J. , Agnholt J. , Höllsberg P. , Dahlerup J. F. 
Published: August 2010

Probiotic bacteria, e.g. Lactobacillus spp., may improve diseases such as chronic inflammatory bowel disease. We examined cytokine production and phenotypic change after in vitro stimulation of T cells from healthy volunteers using different probiotic strains.Methods:  T cells were cultured from colonic biopsies from eight healthy volunteers (Agnholt and Kaltoft, Exp Clin Immunogenet 2001;18:213–25), and dendritic cells were matured from their peripheral blood mononuclear cells. T‐cell cultures were stimulated with autologous bacterial sonicate or strains of Lactobacillus spp., with and without the addition of dendritic cells. Cytokine levels (TNF‐α, IFN‐γ, IL‐10 and GM‐CSF) and phenotype (CD3, CD4, CD25 and CD69) were measured on day 4.Results:  Lactobacillus spp. induced higher productions of TNF‐α and IL‐10 than did autologous bacteria. In presence of dendritic cells, the production of all cytokines increased. However, the increases of IFN‐γ and TNF‐α were more pronounced in wells with autologous bacteria than in wells with Lactobacillus spp. The addition of dendritic cells upregulated CD25 expression without simultaneous upregulation of CD69. The upregulation was pronounced after stimulation with Lactobacillus rhamnosus GG compared with autologous bacteria and other lactobacilli.Discussion:  In presence of dendritic cells, autologous bacteria induced inflammatory cytokines, while probiotics mainly induced regulatory cytokines. Lactobacillus rhamnosus GG induced a regulatory phenotype (cd25+), in part mediated by dendritic cells. Future studies will address whether this shift to a CD25+ phenotype represents a differentiation into competent regulatory T cells. In a clinical context, such cells might be used for treatment of inflammatory diseases.
Plasma TNF‐Binding Capacity and Soluble TNF Receptors in Patients with Juvenile Idiopathic Arthritis
Authors: Bjoernhart B. , Svenningsen P. , Gudbrandsdottir S. , Zak M. , Nielsen S. , Bentzen K. , Müller K. 
Published: August 2010

Background:  Unbalanced production of proinflammatory cytokines may be related to disease progression in rheumatoid arthritis and juvenile idiopathic arthritis (JIA). Within the TNF system, the two agonists, TNF‐α and TNF‐β, also called lymphotoxin‐α (LT), are bound by soluble TNF receptors (sTNFR‐I and ‐II) that act as natural inhibitors of TNF‐induced inflammation. We investigated the plasma levels of sTNFR‐I in parallel with LT‐binding capacity (LTBC) in patients with JIA.Methods:  The levels of sTNFR‐I were measured by ELISA (R&D). LTBC was determined by spiking diluted plasma samples with recombinant LT. Detectable LT was measured by an in‐house ELISA measuring unbound LT only. LTBC was expressed in arbitrary units (AUs) as the percentage value of bound LT to added LT.Result:  In contrast to previous findings of elevated sTNFR levels in patients with various chronic inflammatory diseases, we found slightly reduced sTNFR‐I levels in JIA patients (n = 123) compared with age‐matched healthy controls (n = 37): 1077 pg/ml (819–2280) versus 1185 pg/ml (625–2303) [median (range)], P = 0015. However, the sTNFR‐I levels correlated positively with the number of active joints, physicians' global assessment and CRP. In contrast, patient LTBC values were elevated compared to healthy controls: 44 AU (36–52) versus 31 AU (13–41), P < 0.0001.Conclusion:  Despite overall slightly reduced plasma levels of sTNFR‐I, the capacity to bind TNF was increased in plasma samples from JIA patients. Studies to identify the TNF‐binding substances in plasma are in progress.
Production of Functionally Active Recombinant HLA Molecules Representing the Supertypes B62 and B58 and the Generation of Corresponding Peptide‐Binding Assays and Tetramers
Authors: Røder G. , Lamberth K. , Buus S. 
Published: August 2010

Rationale:  Major histocompatibility complex class I (MHC I) molecules monitor the protein content of the cell by binding small derived peptides and presenting them to cytotoxic CD8+ T cells. The goal of the human MHC project is to predict the binding strength of any given peptide/MHC complex. This prediction allows the design of peptide‐based vaccines. The prediction requires representative binding data from MHC alleles from all the nine HLA supertypes. Here, we describe the genetic construction, protein production and purification as well as the establishment‐binding assays for two recombinant MHC supertype alleles, HLA‐B*1501 and HLA‐B*5801.Methods:  Using the Quikchange Multisite Directed Mutagenesis Kit (Stratagene), codon‐optimized genes encoding HLA‐B*1501 and HLA‐B*5801 are created. The two MHC I molecules are fermented and purified by ion exchange chromatography, hydrophobic interaction chromatography and size exclusion chromatography. The binding (KD) of natural T‐cell epitopes, as well as predicted peptide ligands, is described by radioactive immunoassays (RIAs) and enzyme‐linked immunosorbent assays (ELISAs). The MHC molecules are biotinylated during expression.Results:  The expression of MHC I resulted in multiple disulfide bond isomers, which are separated by hydrophobic interaction chromatography and used in subsequent binding studies resulting in the determination of KD for various peptide ligands ranging from strong binders (KD < 50 nM) to low binders (KD > 5 µM). Tetramerization is visualized by SDS‐PAGE.Conclusion:  An effective method for the production of highly pure MHC I molecules has been applied to HLA‐B*1501 and HLA‐B*5801, and RIA and ELISA binding assays for those alleles have been established, showing the binding of various peptide ligands to the MHC I molecules.
‘Query‐by Committee’— An Efficient Method to Select Information‐Rich Data for the Development of Peptide—HLA‐Binding Predictors
Authors: Lamberth K. , Nielsen M. , Lundegaard C. , Worning P. , Laurmøller S. L. , Lund O. , Brunak S. , Buus S. 
Published: August 2010

Rationale:  We have previously demonstrated that bioinformatics tools such as artificial neural networks (ANNs) are capable of performing pathogen‐, genome‐ and HLA‐wide predictions of peptide–HLA interactions. These tools may therefore enable a fast and rational approach to epitope identification and thereby assist in the development of vaccines and immunotherapy. A crucial step in the generation of such bioinformatics tools is the selection of data representing the event in question (in casu peptide–HLA interaction). This is particularly important when it is difficult and expensive to obtain data. Herein, we demonstrate the importance in selecting information‐rich data and we develop a computational method, query‐by‐committee, which can perform a global identification of such information‐rich data in an unbiased and automated manner. Furthermore, we demonstrate how this method can be applied to an efficient iterative development strategy for these bioinformatics tools.Methods:  A large panel of binding affinities of peptides binding to HLA A*0204 was measured by a radioimmunoassay (RIA). This data was used to develop multiple first generation ANNs, which formed a virtual committee. This committee was used to screen (or ‘queried’) for peptides, where the ANNs agreed (‘low‐QBC’), or disagreed (‘high‐QBC’), on their HLA‐binding potential. Seventeen low‐QBC peptides and 17 high‐QBC peptides were synthesized and tested. The high‐ or low‐QBC data were added to the original data, and new high‐ or low‐QBC second generation ANNs were developed, respectively. This procedure was repeated 40 times.Results:  The high‐QBC‐enriched ANN performed significantly better than the low‐QBC‐enriched ANN in 37 of the 40 tests.Conclusion:  These results demonstrate that high‐QBC‐enriched networks perform better than low‐QBC‐enriched networks in selecting informative data for developing peptide–MHC‐binding predictors. This improvement in selecting data is not due to differences in network training performance but due to the difference in information content in the high‐QBC experiment and in the low‐QBC experiment. Finally, it should be noted that this strategy could be used in many contexts where generation of data is difficult and costly.
BCL‐6 Prevents Mammary Epithelial Apoptosis, Promotes Cell Survival and is Expressed in Breast Carcinoma
Authors: Alenzi F. Q. B. 
Published: August 2010

Background:  Proliferation, differentiation and apoptosis are essential processes in the normal functions of the mammary epithelium. The hypothesis examined in this study is that the transcription factor BCL‐6 is critically important not only for regulating B‐cell growth and development but also for mammary epithelial apoptosis.Methodology:  Twenty breast cancer cases and 31 healthy controls were used to investigate whether BCL‐6 protein in involved in breast cancer (grade III). Full length BCL‐6 cDNA was retrovirally transduced into EpH‐4 cell line. We then used flow cytometry of BrdUrd‐stained cells to investigate the cell‐cycle duration of the control and transduced cell lines. TUNEL was used as a marker of apoptosis to find out differences in the frequencies of apoptotic cells in the control and transduced cell lines. Finally, immunohistochemistry staining was performed to detect BCL‐6 in breast cancer (III).Results:  Restoration of BCL‐6 into EpH‐4 cells not only inhibits apoptosis but also prolongs the cell cycle and results in increased cell size and protein content. The results also indicated that the cell‐cycle time of BCL‐6‐transduced EpH‐4 cells is prolonged by about 3 h, presumably as a result of the action of BCL‐6 at the BCL‐6 at the G1/S transition. We found differences in the frequencies of viable and apoptotic cells in cultures of the parent EpH‐4 cells, control‐transduced EpH‐4 cells and BCL‐6‐transduced EpH‐4 cells. Consistently, we demonstrated that BCL‐6 is expressed in 90% of high grade of breast carcinoma, which is considered as the most aggressive of tumours.Conclusion:  Together, these results suggest that BCL‐6 is likely to be involved in mammary gland development and carcinogenesis.
Preoperative Mannan‐Binding Lectin Pathway and Prognosis in Colorectal Cancer
Authors: Ytting H. , Christensen I. J. , Thiel S. , Jensenius J. C. , Nielsen H. J. 
Published: August 2010

Background:  Deficiency of the mannan‐binding lectin (MBL) pathway of innate immunity leads to increased susceptibility to infections. In patients with colorectal cancer, postoperative infection is associated with poor prognosis. The aim of the present study was to evaluate (1) the relation between the MBL pathway and postoperative infectious complications and survival of patients resected for colorectal cancer and (2) the role of MBL as acute phase reactant compared to CRP.Methods:  Preoperative MBL concentration, MBL/MBL‐associated serine protease (MASP) activity and CRP were determined in serum from 611 patients and 150 healthy controls. The patients were observed for 8 years. Postoperative infections, recurrence and survival were recorded.Results:  The MBL pathway components were increased in the patients (P < 0.0001) compared to healthy controls. Low MBL levels were predictive of pneumonia (P = 0.01), and pneumonia (n = 87) was associated with poor survival (P = 0.003, HR = 1.5, 95% CI 1.1–1.9). MBL and MBL/MASP activity could not predict postoperative overall infections. MBL showed no correlation (spearman's ρ = 0.02, 95% CI −0.06–0.10) with CRP.Conclusions:  Low preoperative MBL levels are predictive of pneumonia, which is associated with poorer survival. MBL concentration and MBL/MASP activity was not predictive of other postoperative infections or long‐term prognosis. MBL apparently is not a surrogate measure of CRP.
Mapping of the Ex Vivo Cellular Immune Response Against the Complete Human Parvovirus B19 Genome During Acute Infection
Authors: Isa A. , Norbeck O. , Pöhlmann C. , Tolfvenstam T. 
Published: August 2010

Background:  Human parvovirus B19 (B19) is a ubiquitous pathogen, normally causing a mild self‐limiting disease, but also capable of causing both significant pathology and long‐term persistence. The small size and stability of the virus makes it suitable for mapping of the full breath and the kinetics of the cellular immune responses following acute viral infection.Methods:  Five patients with acute primary B19 infection were included in the study and followed consecutively for up to 200 weeks. Cellular immune responses were mapped by IFNγ enzyme‐linked immunospot to overlapping peptides spanning the whole B19 genome.Results:  In all five acutely infected patients, we were able to monitor the kinetics of a strong specific cellular immune reaction. Responses peaked at levels of 850–1850 SFC/million PBMCs, roughly corresponding to 0.3–0.6% B19‐specific CD8+ cells circulating in peripheral blood at 10–80 weeks post‐infection. The responses in individual patients were directed to three or four different peptide pools, and the specificity was confined to the same CD8 epitopes present in the pools throughout the follow‐up period. The majority of responses were directed to the virus nonstructural protein, only two patients showed any response to the capsid proteins, elicited by the same epitope in both cases.Conclusion:  The cellular immune responses to acute B19 infection are surprisingly narrow in distribution and remain at high levels for up to 80 weeks post‐infection. The initial epitope specificity is maintained, and the majority of responses target the virus nonstructural protein, which is not included in vaccine preparations, evaluated against the infection.
Presence of Helicobacter pylori Antibodies in Haemodialysis Patients
Authors: Astrinidou‐Vakaloudi A. , Xytsas S. , Diamanti I. , . Ioannidis H , Pangidis P. 
Published: August 2010

Aim:  Renal dysfunction may influence the colonization of gastric mucosa by urea‐splitting bacteria such as Helicobacter pylori, by increasing urea concentrations in the gastric juice. Our aim was to investigate the prevalence of H. pylori in patients with end‐stage renal disease (ESRD), receiving long‐term haemodialysis treatment.Methods:  This study included 40 sera from patients with ESRD (29 male and 11 female) undergoing periodic haemodialysis; mean time of treatment was 42.6 months. Using ELISA technique, we investigated the presence of IgG and IgA antibodies against H. pylori as well as IgG CagA (antibodies specific for CagA(+) strains of H. pylori). Sera from 40 healthy blood donors were used as a control group.Results:  H. pylori IgG antibodies were detected in 32 out of 40 (80%) patients in the dialysis group, while 31/40 (77.5%) tested positive for IgA. IgG CagA antibodies were present in 13 out of 40 (32.5%). Prevalence of H. pylori IgG, IgA and CagA IgG antibodies in the control group was 33, 7 and 15%, respectively.Conclusions:  Although international data suggest that prevalence of H. pylori infection is the same in ESRD patients as in healthy individuals, in our study that seems not to be the case. The higher blood and gastric juice urea levels may be a risk factor (among many others), but more studies are required in order to understand the relation of H. pylori infection in this group of patients.
Release of sVEGF and sVEGFR1 from White Blood Cells and Platelets During Surgery and Stimulation with Bacterial Antigens
Authors: Svendsen M. N. , Werther K. , Bisgaard T. , Christensen I. J. , Nielsen H. J. 
Published: August 2010

Introduction:  The influence of surgery on release of soluble vascular endothelial growth factor (sVEGF) and the soluble vascular endothelial growth factor inhibitory receptor 1 (sVEGFR1) is unknown. We studied the effect of major and minor surgery on potential variations in sVEGF and sVEGFR1 concentrations in vivo and on bacterial antigen‐induced release of sVEGF and sVEGFR1 from whole blood in vitro.Methods:  Sixty‐one patients with abdominal diseases undergoing five different surgical procedures were included. Blood samples were drawn from anaesthetized patients before and after the operation. White blood cells and platelets were counted, and plasma sVEGF and sVEGFR1 was determined by an ELISA method. Whole blood from each blood sample was stimulated in vitro with bacteria‐derived antigens (LPS or protein‐A) and sVEGF and sVEGFR1 levels were subsequently determined in the supernatants. Stimulation with isotonic saline served as control assay.Results:  Neither sVEGF or sVEGFR1 in plasma changed during surgery. In vitro stimulation of blood samples with bacteria‐derived antigens resulted in a significant increase in sVEGF (P < 0.0001) and a less pronounced but still significant increase in sVEGFR1. Release of sVEGF due to stimulation was significantly higher after the operation (nonsignificant), whereas sVEGFR1 release remained largely unchanged after surgery. Correlation between bacterial antigen‐induced release of sVEGF and neutrophile cell count was highly significant (P < 0.0001). There was no correlation between sVEGF and platelet cell count, and bacterial antigen‐induced sVEGFR1 release did not correlate with counts of neutrophils and platelets.Conclusions:  Plasma sVEGF and sVEGFR1 concentrations did not change during surgery. In vitro bacterial stimulation led to increased release of sVEGF and sVEGFR1, which was not significantly amplified during surgery and which may be related to number of circulating neutrophils.