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Bead Array (bead + array)
Kinds of Bead Array Terms modified by Bead Array Selected AbstractsCationic Polyelectrolyte Amplified Bead Array for DNA Detection with Zeptomole Sensitivity and Single Nucleotide Polymorphism SelectivityADVANCED FUNCTIONAL MATERIALS, Issue 16 2010Chun Wang Abstract A highly sensitive strand specific DNA assay, which consists of a peptide nucleic acid (PNA) probe, a cationic conjugated polymer (PFVP), and self-assembled polystyrene beads in microwell arrays on silicon chip, is reported. PFVP, as an efficient signal amplifier and signal reporter, has been specially designed and synthesized to be compatible with commercial confocal microscopes for sensing on solid substrates. The assay operates on the net increase in negative charge at the PNA surface that occurs upon single-stranded DNA hybridization, which subsequently allows complex formation with the positively charged PFVP to favor energy transfer between the polymer and Cy5-labeled target. With maximized surface contact provided by bead arrays and signal amplification provided by PFVP, this assay allows detection of ,300 copies of Cy5-labeled DNA using a commercial confocal microscope. In addition, the same strategy is also extended for label-free DNA detection with a detection sensitivity of 150 attomole. Excellent discrimination against single nucleotide polymorphism (SNP) is also demonstrated for both Cy5-labeled and label-free target detection. This study indicates that cationic conjugated polymers have great potential to be incorporated into the widely used microarray technology for simplified process with improved detection sensitivity. [source] ORIGINAL ARTICLE: Characterization of Cytokine Production by Human Term Placenta Macrophages In VitroAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 6 2008Oleg Pavlov Problem, Macrophages are apparently the only immune cells within placenta villi, yet functions of these cells remain obscure. It has been postulated that placental macrophages accomplish regulatory roles at the fetal,maternal interface by means of wide variety of secreted cytokines. We attempt to analyze the patterns of cytokine production in an isolated population of placental macrophages. Method of study, Macrophages were obtained from term placentas in the absence of spontaneous labor. The basal and lipopolysaccharide (LPS)-stimulated levels of intracellular cytokines were detected by flow cytometry. The basal cytokine secretion was determined by BDŌCytometry Bead Array (BD Biosciences, San Diego, CA, USA). Results, Intracellular IL-1,, IL-1,, IL-6, and TNF, were detected in 31, 27, 4, and 3% CD68+ cells, respectively. Stimulation with LPS increased the proportions of cytokine-producing CD68+ cells to 48, 50, 28, and 49%, respectively. Under basal conditions, levels of released TNF, and IL-6, respectively, were 20- and 25-fold higher when compared with IL-1, while IL-10 was secreted in small but detectable amounts. When a secretory activity was estimated for cytokine-producing cells, the secretion rate for TNF, and IL-6 overwhelmingly surpassed that for IL-1, (TNF,:IL-6:IL-1, ratio was 192:145:1). Conclusion, These results suggest functional heterogeneity of the placental macrophage population and contribute to the elucidation of regulatory roles of these cells in gestation. [source] 2167: Tear film biomarkers as prognostic indicators for recurrent pterygiumACTA OPHTHALMOLOGICA, Issue 2010N ZAKARIA Purpose The aim of this project is to establish the use of IL-6, IL-8 and VEGF as biomarkers in the tear film for early detection of recurrent pterygium. Methods Cytometric Bead Array (CBA) kits will be used to perform multicytokine assays in the tear samples of eyes having pterygium before and after surgical resection of the pterygia. This technique utilizes flow cytometry to determine the concentrations of multiple analytes namely IL-6, IL-8 and VEGF (proposed biomarkers) present in small volumes of tear fluid.Patients with pterygia showing corneal encroachment and requiring surgical excision will be recruited in this study along with a second population of control subjects consisting of individuals with no history of eye diseases or contact lens wear. After instilling a local anesthetic, 3 drops of normal saline will be applied and the at least 50µl of the diluted epithelial secretions collected and stored at -80°C for CBA analysis. From the results we can determine the baseline levels of IL-6, IL-8 and VEGF present in normal epithelial secretions and correlate it with potentially higher levels in the eyes of patients with pterygia. By collecting post op epithelial secretions at different time points along with regular ocular surface photographs and grading of any recurrent pterygia we will be able to ascertain the role of these cytokines and growth factors as biomarkers for recurrent pterygia. Conclusion By establishing higher tear film levels of IL-6, IL-8 and VEGF in eyes with pterygia compared to normal eyes and the return to baseline levels post excision we can begin to ascertain the role of these key players in the pathogenesis of pterygia. [source] Tetomilast suppressed production of proinflammatory cytokines from human monocytes and ameliorated chronic colitis in IL-10-deficient miceINFLAMMATORY BOWEL DISEASES, Issue 11 2008Hitoshi Ichikawa MD Abstract Background: Tetomilast (OPC-6535) was originally developed as a compound inhibiting superoxide production in neutrophils. Although its mechanism of action is not completely understood, phosphodiesterase type 4 inhibitory function has been postulated. The therapeutic effect of PDE4 inhibitors has been reported for chronic inflammatory disorders such as chronic obstructive pulmonary diseases. In this study we aimed to examine whether tetomilast could be a novel drug for inflammatory bowel diseases by further clarifying its antiinflammatory effects. Methods: Cytokines from human peripheral blood mononuclear cells were measured by enzyme-linked immunosorbent assay (ELISA) and Cytokine Beads Array. The transcripts were quantified by reverse-transcriptase polymerase chain reaction (RT-PCR). Phosphorylation of transcription factors was examined by phosflow. To examine its in vivo effect, a once-daily oral dose of tetomilast was tested in murine IL-10,/, chronic colitis. Results: Tetomilast suppressed TNF-, and IL-12 but not IL-10 production from lipopolysaccharide (LPS)-stimulated human monocytes. It suppressed TNF-,, IFN-,, and IL-10 from CD4 lymphocytes. Tetomilast suppressed cytokine production at the transcriptional level but did not alter phosphorylation of p65, ERK, p38, and STAT3. HT-89, a protein kinase A inhibitor, did not abolish the effect of tetomilast, suggesting that it was independent from the classical cAMP/PKA pathway. IL-10 was not essential to the inhibitory effect of tetomilast on TNF-, and IL-12. Tetomilast ameliorated IL-10,/, chronic colitis with reduced clinical symptoms, serum amyloid A, and histological scores with decreased TNF-, mRNA expression. Conclusions: Tetomilast exerts its antiinflammatory effects on human monocytes and CD4 cells. Combined with in vivo data these findings support the feasibility of tetomilast as a novel drug for inflammatory bowel diseases. (Inflamm Bowel Dis 2008) [source] Long-term effects of idiotype vaccination on the specific T-cell response in peripheral blood and bone marrow of multiple myeloma patientsEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 5 2007Amir Osman Abdalla Abstract Objectives:, To elucidate long-term effects of idiotype (Id) vaccination on Id-specific T cells of multiple myeloma (MM) patients and compare Id-specific T-cell responses of peripheral blood with those of bone marrow (BM). Materials and methods:, Id-specific T-cell responses of peripheral blood mononuclear cells (PBMC) were compared with those of BM mononuclear cells (BMMC) in 10 MM patients vaccinated with the Id protein at a median time of 41 months since the last immunization. The PBMC responses at late follow-up were also compared with those during active immunization. The responses were assessed by a proliferation assay, enzyme-linked immunospot (ELISPOT) (,-interferon), cytometric bead array (CBA) for secreted cytokines and quantitative real-time polymerase chain reaction (QRT-PCR) for cytokine gene expression. Results:, At the late testing time, an Id-specific response was detected in PBMC of five patients (ELISPOT, CBA, QRT-PCR) and in BMMC of four patients (CBA, QRT-PCR). A response in both compartments was noted only in three patients. The cytokines gene profile was consistent with a predominance of Th2 cells [interleukin (IL)-4, IL-5, IL-10]. Comparison of the Id-specific responses of PBMC during active immunization with those at the late follow-up showed that the frequency and magnitude of the responses had decreased significantly by time (proliferation/ELISPOT) (P < 0.02) and shifted at the gene level from a Th1 to a Th2 profile (P < 0.05). Conclusion:, Id-specific T cells may decline overtime and shift toward a Th2 response and may be found at a similar frequency of patients in blood and BM. [source] Immunization with a P53 synthetic long peptide vaccine induces P53-specific immune responses in ovarian cancer patients, a phase II trial,INTERNATIONAL JOURNAL OF CANCER, Issue 9 2009Ninke Leffers Abstract The prognosis of ovarian cancer, the primary cause of death from gynecological malignancies, has only modestly improved over the last decades. Immunotherapy is one of the new treatment modalities explored for this disease. To investigate safety, tolerability, immunogenicity and obtain an impression of clinical activity of a p53 synthetic long peptide (p53-SLP) vaccine, twenty patients with recurrent elevation of CA-125 were included, eighteen of whom were immunized 4 times with 10 overlapping p53-SLP in Montanide ISA51. The first 5 patients were extensively monitored for toxicity, but showed no , grade 3 toxicity, thus accrual was continued. Overall, toxicity was limited to grade 1 and 2, mostly locoregional, inflammatory reactions. IFN-, producing p53-specific T-cell responses were induced in all patients who received all 4 immunizations as measured by IFN-, ELISPOT. An IFN-, secretion assay showed that vaccine-induced p53-specific T-cells were CD4+, produced both Th1 and Th2 cytokines as analyzed by cytokine bead array. Notably, Th2 cytokines dominated the p53-specific response. P53-specific T-cells were present in a biopsy of the last immunization site of at least 9/17 (53%) patients, reflecting the migratory capacity of p53-specific T-cells. As best clinical response, stable disease evaluated by CA-125 levels and CT-scans, was observed in 2/20 (10%) patients, but no relationship was found with vaccine-induced immunity. This study shows that the p53-SLP vaccine is safe, well tolerated and induces p53-specific T-cell responses in ovarian cancer patients. Upcoming trials will focus on improving T helper-1 polarization and clinical efficacy. © 2009 UICC [source] Feasibility of a new method to collect exhaled breath condensate in pre-school childrenPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 1-Part-II 2010Philippe P. R. Rosias Rosias PPR, Robroeks CM, van de Kant KD, Rijkers GT, Zimmermann LJ, van Schayck CP, Heynens JW, Jöbsis Q, Dompeling E. Feasibility of a new method to collect exhaled breath condensate in pre-school children. Pediatr Allergy Immunol 2010: 21: e235,e244. © 2009 John Wiley & Sons A/S Exhaled breath condensate (EBC) is a promising non-invasive method to assess respiratory inflammation in adults and children with lung disease. Especially in pre-school children, condensate collection is hampered by long sampling times because of open-ended collection systems. We aimed to assess the feasibility of condensate collection in pre-school children using a closed glass condenser with breath recirculation system, which also collects the residual non-condensed exhaled breath, and subsequently recirculates it back into the condenser. Condensate was collected before and after breath recirculation in 70 non-sedated pre-school children with and without recurrent wheeze. Cytokines (IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p70, IL-13, TNF-,) were measured in 50 ,l samples using ultrasensitive multiplexed liquid bead array. The success rate of condensate collection increased from 64% (without recirculation) to 83% (after breath recirculation), and mean condensate volume from 214 to 465 ,l respectively. Detection of cytokines was successful in 95,100% of samples. Cytokine concentrations before and after breath recirculation were not different (p > 0.232). In asthmatic children, only TNF-, concentrations were significantly decreased, compared to non-asthmatics. In pre-school children, the collection of EBC is feasible using a new closed glass condenser with breath recirculation system. This new method may help to assess , non-invasively , cytokine profiles in asthmatic and non-asthmatic pre-school children. [source] Downregulation of pro-inflammatory cytokines by lupeol measured using cytometric bead array immunoassayPHYTOTHERAPY RESEARCH, Issue 1 2010Sheikh Fayaz Ahmad Abstract The objective of the study was to investigate the activity of Lupeol (LUP) on proinflammatory and anti-inflammatory cytokines in the pleural exudate from male swiss albino mice. We applied Cytometric bead array technology for simultaneously measurement of these cytokines in pleurisy induced mice treated with lupeol in graded oral doses. Cytometric bead array uses the sensitivity of amplified fluorescence detection by flowcytometer to measure soluble analytes in a particle based immune assay. This assay can accurately quantitate 5 cytokines in a 50 microlitre sample volume. Oral administration of LUP at doses of 25, 50, 100 and 200 mg/kg p.o. produced dose related inhibition of IL-2, IFN-gamma and TNF- , in the pleural exudate with the most significant effect at 100 mg/kg oral dose. LUP had a non significant inhibitory effect on the levels of IL-4 and IL-5. Copyright © 2009 John Wiley & Sons, Ltd. [source] Comparative protein profiling of serum and plasma using an antibody suspension bead array approachPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 3 2010Jochen M. Schwenk Abstract In the pursuit towards a systematic analysis of human diseases, array-based approaches within antibody proteomics offer high-throughput strategies to discover protein biomarkers in serum and plasma. To investigate the influence of sample preparation on such discovery attempts, we report on a systematic effort to compare serum and plasma protein profiles determined with an antibody suspension bead array. The intensity levels were used to define protein profiles and no significant differences between serum and plasma were observed for 79% of the 174 antibodies (targeting 156 proteins). By excluding 36 antibodies giving rise to differential intensity levels, cluster analysis revealed donor-specific rather than preparation-dependent grouping. With a cohort from a clinically relevant medical condition, the metabolic syndrome, the influence of the sample type on a multiplexed biomarker discovery approach was further investigated. Independent comparisons of protein profiles in serum and plasma revealed an antibody targeting ADAMTSL-4, a protein that would qualify to be studied further in association with the condition. In general, the preparation type had an impact on the results of the applied antibody suspension bead array, and while the technical variability was equal, plasma offered a greater biological variability and allowed to give rise to more discoveries than serum. [source] Brain Death Activates Donor Organs and Is Associated with a Worse I/R Injury After Liver TransplantationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 6 2007S. Weiss The majority of transplants are derived from donors who suffered from brain injury. There is evidence that brain death causes inflammatory changes in the donor. To define the impact of brain death, we evaluated the gene expression of cytokines in human brain dead and ideal living donors and compared these data to organ function following transplantation. Hepatic tissues from brain dead (n = 32) and living donors (n = 26) were collected at the time of donor laparotomy. Additional biopsies were performed before organ preservation, at the time of transplantation and one hour after reperfusion. Cytokines were assessed by real-time reverse transcriptase,polymerase chain reaction (RT,PCR) and cytometric bead array. Additionally, immunohistological analysis of tissue specimens was performed. Inflammatory cytokines including IL-6, IL-10, TNF-,, TGF-, and MIP-1, were significantly higher in brain dead donors immediately after laparotomy compared to living donors. Cellular infiltrates significantly increased in parallel to the soluble cytokines IL-6 and IL-10. Enhanced immune activation in brain dead donors was reflected by a deteriorated I/R injury proven by elevated alanin-amino-transferase (ALT), aspartat-amino-transferase (AST) and bilirubin levels, increased rates of acute rejection and primary nonfunction. Based on our clinical data, we demonstrate that brain death and the events that precede it are associated with a significant upregulation of inflammatory cytokines and lead to a worse ischemia/reperfusion injury after transplantation. [source] Review modeling the free solution and gel electrophoresis of biopolymers: The bead array-effective medium modelBIOPOLYMERS, Issue 2-3 2007Stuart A. Allison Abstract Free solution and gel electrophoresis is an extremely useful tool in the separation of biopolymers. The complex nature of biopolymers, coupled with the usefulness of electrophoretic methods, has stimulated the development of theoretical modeling over the last 30 years. In this work, these developments are first reviewed with emphasis on Boundary Element and bead methodologies that enable the investigator to design realistic models of biopolymers. In the present work, the bead methodology is generalized to include the presence of a gel through the Effective Medium model. The biopolymer is represented as a bead array. A peptide, for example, made up of N amino acids is modeled as 2N beads. Duplex DNA is modeled as a discrete wormlike chain consisting of touching beads. The technical details of the method are placed in three Appendices. To illustrate the accuracy and effectiveness of the approach, two applications are considered. Model studies on both the free solution mobility of 73 peptides ranging in size from 2 to 42 amino acids, and the mobility of short duplex DNA in dilute agarose gels are discussed. © 2007 Wiley Periodicals, Inc. Biopolymers 87: 102,114, 2007. This article was originally published online as an accepted preprint. The "Published Online" date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com [source] 3364: Cytokines in enucleated eyesACTA OPHTHALMOLOGICA, Issue 2010MJ JAGER Purpose One of the prognostically bad parameters in uveal melanoma is the presence of an inflammatory phenotype, characterized by an increased expression of HLA antigens and an immunologic infiltrate. We wondered whether the presence of specific chemokines and cytokines in the aqueous humor (AqH) from uveal melanoma-containing eyes is associated with this inflammatory phenotype, with the presence of macrophages, and/or with survival. Methods Directly following enucleation, AqH was obtained from 37 eyes containing uveal melanoma. Samples were stored at -80 °C till use. Using a multiplex bead array, 15 different cytokines were measured. Determination of intratumoral macrophages was performed by immunohistochemistry and immunofluorescence. The presence of specific cytokines was compared to histopathological, genetic and clinical tumor characteristics, as well as patient survival. Results Several cytokines showed a significantly higher expression in the AqH from uveal melanoma-containing eyes compared to the AqH from eyes undergoing cataract surgery. Only MCP-3 was associated with the presence of macrophages and the tumor promoting M2-type macrophage in uveal melanoma patients. Hardly any correlations were found between cytokine levels and known prognostic factors for uveal melanoma. Also, cytokine levels were not of predictive value for survival. Conclusion Although increased levels of inflammation-related cytokines are present in the AqH of uveal melanoma-containing eyes, hardly any associations with the presence of macrophages and their subtypes, with clinical and histopathological parameters, and prognosis were found. [source] Inhaled corticosteroid therapy reduces cytokine levels in sputum from very preterm infants with chronic lung diseaseACTA PAEDIATRICA, Issue 1 2009Rie Honda Abstract Aim: To evaluate the effects of inhaled corticosteroid therapy and high-frequency oscillatory ventilation (oscillation) on preterm infants with chronic lung disease (CLD). Methods: Ten infants with CLD who received inhaled corticosteroid therapy were enrolled. Week 1 was defined as the first week of therapy. The concentrations of interleukin (IL)-8, tumour necrosis factor-, (TNF-,), IL-1,, IL-6, IL-10 and IL-12p70 in serial sputum specimens from the infants were determined using a cytometric bead array. Results: The sputum concentrations of IL-8 obtained from the infants during week 3,4 were significantly lower than those obtained before therapy and during week 1,2. The sputum concentrations of TNF-,, IL-6 and IL-10 during week 3,4 were significantly lower than the concetrations during week 1,2. The ratio of IL-8 levels during week 1,2 to those before therapy in infants who received oscillation (n = 4) was significantly lower than in those who received intermittent mandatory ventilation (n = 6). Conclusion: Inhaled corticosteroids may be associated with a decrease in pro-inflammatory cytokine levels in sputum from infants with CLD from 2 weeks after the start of therapy. Our further investigations suggest that therapy with oscillation modulated airway inflammation earlier than therapy with intermittent mandatory ventilation. [source] Cationic Polyelectrolyte Amplified Bead Array for DNA Detection with Zeptomole Sensitivity and Single Nucleotide Polymorphism SelectivityADVANCED FUNCTIONAL MATERIALS, Issue 16 2010Chun Wang Abstract A highly sensitive strand specific DNA assay, which consists of a peptide nucleic acid (PNA) probe, a cationic conjugated polymer (PFVP), and self-assembled polystyrene beads in microwell arrays on silicon chip, is reported. PFVP, as an efficient signal amplifier and signal reporter, has been specially designed and synthesized to be compatible with commercial confocal microscopes for sensing on solid substrates. The assay operates on the net increase in negative charge at the PNA surface that occurs upon single-stranded DNA hybridization, which subsequently allows complex formation with the positively charged PFVP to favor energy transfer between the polymer and Cy5-labeled target. With maximized surface contact provided by bead arrays and signal amplification provided by PFVP, this assay allows detection of ,300 copies of Cy5-labeled DNA using a commercial confocal microscope. In addition, the same strategy is also extended for label-free DNA detection with a detection sensitivity of 150 attomole. Excellent discrimination against single nucleotide polymorphism (SNP) is also demonstrated for both Cy5-labeled and label-free target detection. This study indicates that cationic conjugated polymers have great potential to be incorporated into the widely used microarray technology for simplified process with improved detection sensitivity. [source] Plasma concentrations of VCAM-1 and PAI-1: A predictive biomarker for post-operative recurrence in colorectal cancerCANCER SCIENCE, Issue 8 2010Yasuhide Yamada This prospective study used antibody suspension bead arrays to identify biomarkers capable of predicting post-operative recurrence with distal metastasis in patients with colorectal cancer. One hundred colorectal cancer patients who underwent surgery were enrolled in this study. The median follow-up period was 3.9 years. The pre-operative plasma concentrations of 24 angiogenesis-related molecules were analyzed with regard to the TNM stage and the development of post-operative recurrence. The concentrations of half of the examined molecules (13/24) increased significantly according to the TNM stage (P < 0.05). Meanwhile, a multivariate logistic regression analysis revealed that the concentrations of vascular cell adhesion molecule 1 (VCAM-1) and plasminogen activator inhibitor-1 (PAI-1) were significantly higher in the post-operative recurrence group. The VCAM-1 and PAI-1 model discriminated post-operative recurrence with an area under the curve of 0.82, a sensitivity of 0.75, and a specificity of 0.73. A leave-one-out cross-validation was applied to the model to assess the prediction performance, and the result indicated that the cross-validated error rate was 12.5% (12/96). In conclusion, our results demonstrate that antibody suspension bead arrays are a powerful tool to screen biomarkers in the clinical setting, and the plasma levels of VCAM-1 and PAI-1 together may be a promising biomarker for predicting post-operative recurrence in patients with colorectal cancer. (Cancer Sci 2010) [source] | |||||||||||||