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Lymphoblastoid Cell Lines (lymphoblastoid + cell_line)
Selected AbstractsX-Irradiation Induces Up-regulation of ATM Gene Expression in Wild-type Lymphoblastoid Cell Lines, but Not in Their Heterozygous or Homozygous Ataxia-telangiectasia CounterpartsCANCER SCIENCE, Issue 6 2001Yuko Hirai Ataxia-telangiectasia (AT) is an autosomal recessive disease. The relevant gene has been cloned and designated ATM. We studied the expression of both ATM mRNA and the ATM protein in unirradi-ated and X-irradiated EBV (Epstein-Barr virus)-transformed lymphoblastoid cell lines (LCLs) derived from donors who were normal (ATM+/+), AT heterozygotes (ATM+/,), or AT homozy-gotes (ATM,/,), respectively. In ATM+/+ LCLs, the levels of ATM mRNA were found to have increased by approximately 1.5-fold within 1 h of exposure to 10 Gy of X-rays, while the ATM protein levels had increased by 1.5- to 2.0-fold within 2 to 3 h of irradiation. The wild-type mRNA and protein levels both returned to their basal values fairly quickly after this tune. The results obtained with the ATM+/, LCLs were quite different, however: neither the mRNA nor protein levels were found to have increased as a consequence of X-irradiation in any ATM+/, LCL. Twelve of the mutations in the ATM,/, LCLs we used were truncating mutations, and we suspected that the corresponding truncated ATM proteins would be too labile to be detected by western blot analysis. However, five of the ATM,/, LCLs produced mutant ATM proteins that were identical in molecular weight to the wild-type ATM protein. When cells from three of these five clones were exposed to X-rays, transcription of the mutant ATM genes appeared to reduce somewhat, as were the levels of protein being produced. These results suggest that the normal ATM gene responds to ionizing radiation by up-regulating its activity, whereas none of the mutant ATM genes we studied were able to respond in this way. [source] G2 -phase radiation response in lymphoblastoid cell lines from Nijmegen breakage syndromeCELL PROLIFERATION, Issue 2 2002A. Antoccia The relationship between G2 -phase checkpoint activation, cytoplasmic cyclin-B1 accumulation and nuclear phosphorylation of p34CDC2 was studied in Nijmegen breakage syndrome cells treated with DNA damaging agents. Experiments were performed on lymphoblastoid cell lines from four Nijmegen breakage syndrome patients with different mutations, as well as on cells from an ataxia telangiectasia patient. Lymphoblastoid cell lines were irradiated with 0.50,2 Gy X-rays and the percentage of G2 -phase accumulated cells was evaluated by means of flow cytometry in samples that were harvested 24 h later. The G2 -checkpoint activation was analysed by scoring the mitotic index at 2 and 4 h after treatment with 0.5 and 1 Gy X-rays and treatment with the DNA double-strand break inducer calicheamicin-,1. Cytoplasmic accumulation of cyclin-B1 was evaluated by means of fluorescence immunostaining or Western blotting, in cells harvested shortly after irradiation with 1 and 2 Gy. The extent of tyrosine 15-phosphorylated p34CDC2 was assessed in the nuclear fractions. Nijmegen breakage syndrome cells showed suboptimal G2 -phase checkpoint activation respect to normal cells and were greatly different from ataxia telangiectasia cells. Increased cytoplasmic cyclin-B1 accumulation was detected by both immunofluorescence and immunoblot in normal as well as in Nijmegen breakage syndrome cells. Furthermore, nuclear p34CDC2. phosphorylation was detected at a higher level in Nijmegen breakage syndrome than in ataxia telangiectasia cells. In conclusion, our data do not suggest that failure to activate checkpoints plays a major role in the radiosensitivity of Nijmegen breakage syndrome cells. [source] Allelic imbalance of expression and epigenetic regulation within the alpha-synuclein wild-type and p.Ala53Thr alleles in Parkinson disease,HUMAN MUTATION, Issue 6 2010Gerassimos E. Voutsinas Abstract Genetic alterations in the alpha-synuclein (SNCA) gene have been implicated in Parkinson Disease (PD), including point mutations, gene multiplications, and sequence variations within the promoter. Such alterations may be involved in pathology through structural changes or overexpression of the protein leading to protein aggregation, as well as through impaired gene expression. It is, therefore, of importance to specify the parameters that regulate SNCA expression in its normal and mutated state. We studied the expression of SNCA alleles in a lymphoblastoid cell line and in the blood cells of a patient heterozygous for p.Ala53Thr, the first mutation to be implicated in PD pathogenesis. Here, we provide evidence that: (1) SNCA shows monoallelic expression in this patient, (2) epigenetic silencing of the mutated allele involves histone modifications but not DNA methylation, and (3) steady-state mRNA levels deriving from the normal SNCA allele in this patient exceed those of the two normal SNCA alleles combined, in matching, control individuals. An imbalanced SNCA expression in this patient is thus documented, with silencing of the p.Ala53Thr allele and upregulation of the wild-type-allele. This phenomenon is demonstrated for a first time in the SNCA gene, and may have important implications for PD pathogenesis. Hum Mutat 31:1,7, 2010. © 2010 Wiley-Liss, Inc. [source] Endogenous DNA damage and testicular germ cell tumorsINTERNATIONAL JOURNAL OF ANDROLOGY, Issue 6 2009M. B. Cook Summary Testicular germ cell tumors are comprised of two histologic groups, seminomas and non-seminomas. We postulated that the possible divergent pathogeneses of these histologies may be partially explained by variable levels of net endogenous DNA damage. To test our hypothesis, we conducted a case,case analysis of 51 seminoma and 61 non-seminoma patients using data and specimens from the Familial Testicular Cancer study and the U.S. Radiologic Technologists cohort. A lymphoblastoid cell line was cultured for each patient and the alkaline comet assay was used to determine four parameters: tail DNA, tail length, comet distributed moment (CDM) and Olive tail moment (OTM). Odds ratios (OR) and 95% confidence intervals (95% CI) were estimated using logistic regression. Values for tail length, tail DNA, CDM and OTM were modelled as categorical variables using the 50th and 75th percentiles of the seminoma group. Tail DNA was significantly associated with non-seminoma compared with seminoma (OR50th percentile = 3.31, 95% CI: 1.00, 10.98; OR75th percentile = 3.71, 95% CI: 1.04, 13.20; p for trend = 0.039). OTM exhibited similar, albeit statistically non-significant, risk estimates (OR50th percentile = 2.27, 95% CI: 0.75, 6.87; OR75th percentile = 2.40, 95% CI: 0.75, 7.71; p for trend = 0.12) whereas tail length and CDM showed no association. In conclusion, the results for tail DNA and OTM indicate that net endogenous levels are higher in patients who develop non-seminoma compared with seminoma. This may partly explain the more aggressive biology and younger age-of-onset of this histologic subgroup compared with the relatively less aggressive, later-onset seminoma. [source] Inhibition of factor VIII with a partially inhibitory human recombinant monoclonal antibody prevents thrombotic events in a transgenic model of type II HBS antithrombin deficiency in miceJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 1 2004M. Dewerchin Summary., Venous thromboembolic disease is a major cause of morbidity and mortality, necessitating antithrombotic therapy. A human monoclonal anti-factor (F)VIII antibody, LCL-mAb-LE2E9, produced by a lymphoblastoid cell line derived from a hemophilia A patient with inhibitor to wild-type but not mutant self FVIII, was previously reported to achieve efficient inhibition of thrombosis in an experimental vena cava thrombosis model in mice. Here, the antithrombotic efficacy of a recombinant DNA-derived version of this anti-FVIII antibody (rec-mAb-LE2E9) was tested in mice which carry a type II heparin binding site antithrombin deficiency mutation and display spontaneous chronic thrombosis in several sites including the penile vein of sexually active males. The recombinant anti-FVIII antibody (100 µg, repeated after 3 days) prevented thrombotic priapism in all treated males, whereas all control animals treated with saline (group of four animals) developed priapism within 6 days after mating (P < 0.05 for treated vs. saline). The rec-mAb-LE2E9 and the original LCL-mAb-LE2E9 were equally effective (five and seven males/group, respectively). These results confirm that FVIII inhibition represents a potent antithrombotic strategy, and show that both LCL-mAb-LE2E9 and rec-mAb-LE2E9 efficiently prevent thrombosis in a physiological model representative of thrombosis in patients with a severe prothrombotic risk. [source] Capacity of robot handling for Epstein-Barr virus transformationCELL PROLIFERATION, Issue 1 2009I.-C. Chang Objectives:, Epstein-Barr virus (EBV) transformation has been described as a routine method to establish human B lymphoblastoid cell lines. Each established lymphoblastoid cell line represents one unique genetic information carrier and can produce unlimited quantities of DNA materials available for downstream applications and research. Undoubtedly, it is of great value to human clinical and experimental genetic studies. However, the current process of EBV transformation requires much manpower in the routine renewal of medium, which is time-consuming. This situation can become a serious problem especially when establishing a human B lymphoblastoid cell bank. A modified and cost-effective protocol for EBV transformation should be considered. Materials and methods:, In the present study, process in EBV transformation was modified to fit the requirements of robot handling. Results:, 1 mL of whole blood was demonstrated to be sufficient to perform EBV transformation. Additionally, EBV transformation can performed in 96-deep-well plates that are directly and widely used with automatic work platforms. Conclusions:, Based on these facts, a process of EBV transformation can be modified to fit the requirements of robot handling. [source] Removal of benzo(a)pyrene diol epoxide (BPDE)-DNA adducts as a measure of DNA repair capacity in lymphoblastoid cell lines from sisters discordant for breast cancerENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 2 2002Grazyna Motykiewicz Abstract The mutagen sensitivity assay is one of the approaches used to investigate individual DNA repair capacity. This method is based on the premise that after in vitro treatment with a test mutagen, DNA from subjects with defective repair will be more damaged than DNA from those with an efficient repair system. However, very little is known about unmeasured processes that occur between cell treatment and final assessment of DNA damage. To develop a more precise assay, we modified the traditional mutagen sensitivity assay to also include measurement of DNA damage after culturing cells in the absence of mutagen. First, we treated apparently normal and xeroderma pigmentosum lymphoblastoid cell lines with various doses of benzo(a)pyrene diol epoxide (BPDE) and harvested cells at different time points. A polyclonal antiserum against BPDE-DNA was used to quantitate levels of adducts by immunoslot-blot and immunohistochemistry. Selected conditions included treatment with 10 ,M BPDE, a 4-hr culture in mutagen-free medium, and immunohistochemical measurement of BPDE-DNA adducts. The method was then applied in a pilot study to 50 lymphoblastoid lines from sisters discordant for breast cancer. There was no significant difference between cases and controls in the level of BPDE-DNA adducts in lymphoblasts harvested immediately after BPDE treatment. However, after a 4-hr culture in mutagen-free medium, the level of adducts was significantly higher (P = 0.006) among cases than in controls. There was a two-fold increase in mean adduct removal in lines from nonaffected as compared to affected sisters (44% and 22% decrease, respectively). DNA repair capacity was predictive of case status (P = 0.04) in logistic regression analysis. This method, which can be easily applied to large numbers of samples, should be useful in studies to investigate the role of DNA repair in cancer risk. Environ. Mol. Mutagen. 40:93,100, 2002. © 2002 Wiley-Liss, Inc. [source] Gene expression analysis in absence epilepsy using a monozygotic twin designEPILEPSIA, Issue 9 2008Ingo Helbig Summary Purpose: To identify genes involved in idiopathic absence epilepsies by analyzing gene expression using a monozygotic (MZ) twin design. Methods: Genome-wide gene expression in lymphoblastoid cell lines (LCLs) was determined using microarrays derived from five discordant and four concordant MZ twin pairs with idiopathic absence epilepsies and five unaffected MZ twin pairs. Gene expression was analyzed using three strategies: discordant MZ twins were compared as matched pairs, MZ twins concordant for epilepsy were compared to control MZ twins, and a singleton design of affected versus unaffected MZ twin individuals was used irrespective of twin pairing. An overlapping gene list was generated from these analyses. Dysregulation of genes recognized from the microarray experiment was validated using quantitative real time PCR (qRT-PCR) in the twin sample and in an independent sample of 18 sporadic absence cases and 24 healthy controls. Results: Sixty-five probe sets were identified from the three combined microarray analysis strategies. Sixteen genes were chosen for validation and nine of these genes confirmed by qRT-PCR in the twin sample. Differential expression for EGR1 (an immediate early gene) and RCN2 (coding for the calcium-binding protein Reticulocalbin 2) were reconfirmed by qRT-PCR in the independent sample. Discussion: Using a unique sample of discordant MZ twins, our study identified genes with altered expression, which suggests novel mechanisms in idiopathic absence epilepsy. Dysregulation of EGR1 and RCN2 is implicated in idiopathic absence epilepsy. [source] Increased expression of microRNA-155 in Epstein-Barr virus transformed lymphoblastoid cell linesGENES, CHROMOSOMES AND CANCER, Issue 1 2006Jinmai Jiang First page of article [source] Classifying MLH1 and MSH2 variants using bioinformatic prediction, splicing assays, segregation, and tumor characteristicsHUMAN MUTATION, Issue 5 2009Sven Arnold Abstract Reliable methods for predicting functional consequences of variants in disease genes would be beneficial in the clinical setting. This study was undertaken to predict, and confirm in vitro, splicing aberrations associated with mismatch repair (MMR) variants identified in familial colon cancer patients. Six programs were used to predict the effect of 13 MLH1 and 6 MSH2 gene variants on pre-mRNA splicing. mRNA from cycloheximide-treated lymphoblastoid cell lines of variant carriers was screened for splicing aberrations. Tumors of variant carriers were tested for microsatellite instability and MMR protein expression. Variant segregation in families was assessed using Bayes factor causality analysis. Amino acid alterations were examined for evolutionary conservation and physicochemical properties. Splicing aberrations were detected for 10 variants, including a frameshift as a minor cDNA product, and altered ratio of known alternate splice products. Loss of splice sites was well predicted by splice-site prediction programs SpliceSiteFinder (90%) and NNSPLICE (90%), but consequence of splice site loss was less accurately predicted. No aberrations correlated with ESE predictions for the nine exonic variants studied. Seven of eight missense variants had normal splicing (88%), but only one was a substitution considered neutral from evolutionary/physicochemical analysis. Combined with information from tumor and segregation analysis, and literature review, 16 of 19 variants were considered clinically relevant. Bioinformatic tools for prediction of splicing aberrations need improvement before use without supporting studies to assess variant pathogenicity. Classification of mismatch repair gene variants is assisted by a comprehensive approach that includes in vitro, tumor pathology, clinical, and evolutionary conservation data. Hum Mutat 0, 1,14, 2009. © 2009 Wiley-Liss, Inc. [source] Expression of 5-lipoxygenase (5-LOX) in T lymphocytesIMMUNOLOGY, Issue 2 2007Jeanne M. Cook-Moreau Summary 5-lipoxygenase (5-LOX) is the key enzyme responsible for the synthesis of the biologically active leukotrienes. Its presence has been reported in cells of the myeloid lineage and B lymphocytes but has not been formally defined in T lymphocytes. In this study, we provide evidence for 5-LOX expression on both transcriptional and translational levels in highly purified peripheral blood T cells as well as in human T lymphoblastoid cell lines (MOLT4 and Jurkat). Messenger RNA (mRNA) of 5-LOX was amplified by conventional reverse transcription,polymerase chain reaction (RT-PCR; MOLT4 and Jurkat cells) and by in situ RT-PCR (T lymphocytes). 5-LOX protein expression was confirmed by Western blot and immunofluorescence studies. 5-LOX was present primarily in the cytoplasm with some nuclear localization and was translocated to the nuclear periphery after culture in a mitosis-supporting medium. Fluorescence-activated cell sorter analysis of different T-lymphocyte populations, including CD4, CD8, CD45RO, CD45RA, T helper type 2, and T-cell receptor-,, and -,, expressing cells, did not identify a differential distribution of the enzyme. Purified peripheral blood T lymphocytes were incapable of synthesizing leukotrienes in the absence of exogenous arachidonic acid. Jurkat cells produced leukotriene C4 and a small amount of leukotriene B4 in response to CD3,CD28 cross-linking. This synthesis was abolished by two inhibitors of leukotriene synthesis, MK-886 and AA-861. The presence of 5-LOX in T lymphocytes but the absence of endogenous lipoxygenase metabolite production compared to Jurkat cells may constitute a fundamental difference between resting peripheral lymphocytes and leukaemic cells. [source] In vitro Epstein-Barr virus-immortalized lymphoma cell line carrying t(9;14)(p13;q32) chromosome abnormality, derived from splenic lymphoma with villous lymphocytesINTERNATIONAL JOURNAL OF CANCER, Issue 2 2006Masanori Daibata Abstract We herein describe splenic lymphoma with villous lymphocytes (SLVL) carrying t(9;14)(p13;q32). The t(9;14)(p13;q32) is a rare reciprocal chromosome translocation found in a subset of B-cell malignancies, mainly in low-grade non-Hodgkin's lymphomas. In t(9;14)(p13;q32), PAX-5 gene on 9p13 is involved with the immunoglobulin heavy-chain gene on 14q32. It has been thought that the deregulated expression of PAX-5 as a result of t(9;14)(p13;q32) may contribute to abnormal cell proliferation. Although continuous cell lines are invaluable tools for studying lymphomagenesis in the t(9;14)(p13;q32)-bearing lymphomas, establishment of such cell lines is extremely difficult since they are usually mature B-cell malignancies. In an attempt to transform the SLVL cells into a proliferating cell line, we examined the responses of the cells to infection by Epstein-Barr virus (EBV). SLVL cells were found to be susceptible to immortalization by EBV, resulting in a permanent cell line. The cell line, designated SL-15, possessed the t(9;14)(p13;q32). Genotype analysis and immunophenotype profiles confirmed that the cell line arose from the primary lymphoma cells. The cells had characteristic cytoplasmic villi. SL-15 cells has been growing over 2 years equivalent to 350,400 population doubling levels without proliferative crisis that is often observed in EBV-positive lymphoblastoid cell lines. Furthermore, SL-15 cells, when inoculated into nude mice, formed t(9;14)(p13;q32)-bearing tumors with cytoplasmic villi. The validated SLVL-derived cell line provide a useful model system to study molecular biology of t(9;14)(p13;q32)-bearing B-cell malignancies as well as lymphomagenesis of SLVL in vitro and in vivo. © 2005 Wiley-Liss, Inc. [source] Gene expression profiles associated with aging and mortality in humansAGING CELL, Issue 3 2009Richard A. Kerber Summary We investigated the hypothesis that gene expression profiles in cultured cell lines from adults, aged 57,97 years, contain information about the biological age and potential longevity of the donors. We studied 104 unrelated grandparents from 31 Utah CEU (Centre d'Etude du Polymorphisme Humain , Utah) families, for whom lymphoblastoid cell lines were established in the 1980s. Combining publicly available gene expression data from these cell lines, and survival data from the Utah Population Database, we tested the relationship between expression of 2151 always-expressed genes, age, and survival of the donors. Approximately 16% of 2151 expression levels were associated with donor age: 10% decreased in expression with age, and 6% increased with age. Cell division cycle 42 (CDC42) and CORO1A exhibited strong associations both with age at draw and survival after draw (multiple comparisons-adjusted Monte Carlo P -value < 0.05). In general, gene expressions that increased with age were associated with increased mortality. Gene expressions that decreased with age were generally associated with reduced mortality. A multivariate estimate of biological age modeled from expression data was dominated by CDC42 expression, and was a significant predictor of survival after blood draw. A multivariate model of survival as a function of gene expression was dominated by CORO1A expression. This model accounted for approximately 23% of the variation in survival among the CEU grandparents. Some expression levels were negligibly associated with age in this cross-sectional dataset, but strongly associated with inter-individual differences in survival. These observations may lead to new insights regarding the genetic contribution to exceptional longevity. [source] Possible involvement in oncogenesis of a single base mutation in an internal ribosome entry site of Epstein,Barr nuclear antigen 1 mRNAJOURNAL OF MEDICAL VIROLOGY, Issue 4 2004Rika Endo Abstract It has been reported recently that the U leader exon located within the 5, untranslated region of Epstein,Barr nuclear antigen 1 (EBNA1) gene contains an internal ribosome entry site (IRES) element. Sequence analysis of the U leader exon was undertaken in samples from 19 patients with infectious mononucleosis and 19 patients with lethal lymphoproliferative diseases and in 15 spontaneously established lymphoblastoid cell lines. The sequence was conserved except for a single base substitution (T-C) at position 67,585. Although the mutation was detected in only one case of infectious mononucleosis, it was found in more than half of the lethal lymphoproliferative diseases and all lymphoblastoid cell lines. The results suggest that a mutation in the IRES element affects EBNA1 gene expression at the translational level and provides Epstein,Barr virus (EBV)-infected cells with a growth advantage, leading to immortalization of cells in vitro and to the development of lethal lymphoproliferative diseases in vivo. J. Med. Virol. 72:630,634, 2004. © 2004 Wiley-Liss, Inc. [source] Ex vivo generation of cytokine-induced killer cells (CD3+ CD56+) from post-stem cell transplant pediatric patients against autologous,Epstein,Barr virus,transformed lymphoblastoid cell linesPEDIATRIC TRANSPLANTATION, Issue 5 2007Sawang Petvises Abstract:, EBV-PTLDs affect as high as 20% of SCT recipients especially those with T-cell depleted grafts while high mortality rates were also noted. Adoptive allogeneic and autologous CTLs have a therapeutic potential in this setting. However, the process of expansion of these cells is tedious and time consuming in both allogeneic and autologous CTL generation. For the allogeneic SCT, another major obstacle is unavailability of donors especially in an unrelated SCT setting. The aim of the present study was therefore to investigate the efficacy of autologous CIK cells (CD3+ CD56+) against autologous EBV-LCLs from post-SCT pediatric patients. We could demonstrate that CIK cells can be generated within two wk and did show the significant cytotoxicity against autologous EBV-LCLs. CIK cells may provide a potent tool for use in post-transplantation adoptive immunotherapy. [source] Successful In Vitro Priming of EBV-Specific CD8+ T Cells Endowed with Strong Cytotoxic Function from T Cells of EBV-Seronegative ChildrenAMERICAN JOURNAL OF TRANSPLANTATION, Issue 9 2006P. Comoli Epstein-Barr virus (EBV)-seronegative transplant recipients are at high risk of developing EBV-associated post-transplant lymphoproliferative disorder (PTLD), and would maximally benefit from an EBV-directed T-cell therapy for prevention or treatment of PTLD. So far, efforts to activate CD8+ EBV-specific cytotoxic T lymphocytes (CTL) endowed with high specific cytotoxicity from EBV-seronegative children have failed. We compared the CD8+ CTL priming efficiency of three different modified activation protocols, based on lymphoblastoid cell lines (LCL) stimulation potentially enhanced by either LCL presentation through dendritic cells, or selection of IFN-,+ cultured cells, or culture in the presence of rhIL-12 and rhIL-7, according to the standard protocol for reactivation of EBV-specific CTL. We found that only specific LCL stimulation in the presence of rhIL-12 and rhIL-7 was able to reproducibly expand EBV-specific CD8+ CTL endowed with strong cytotoxic activity from truly EBV-seronegative children. The lines thus activated, which included specificities toward EBV latent and lytic proteins, showed high percentage CD8+ T cells, with <10% naïve CD8+/CCR7+/CD45RA+ cells. Overall, the total number of CD8+ central memory cells, and of CCR7 T-cell effectors was comparable to that observed in healthy EBV-seropositive controls. In conclusion, it is feasible to activate EBV-specific CD8+ CTL with suitable characteristics for in vivo employment from EBV-seronegative children. [source] Deiminated Epstein-Barr virus nuclear antigen 1 is a target of anti,citrullinated protein antibodies in rheumatoid arthritisARTHRITIS & RHEUMATISM, Issue 3 2006Federico Pratesi Objective To test the hypothesis that deimination of viral sequences containing Arg,Gly repeats could generate epitopes recognized by anti,citrullinated protein antibodies (ACPAs) that are present in rheumatoid arthritis (RA) sera. Methods Multiple antigen peptides derived from Epstein-Barr virus (EBV),encoded Epstein-Barr nuclear antigen 1 (EBNA-1) were synthesized, substituting the arginines with citrulline, and were used to screen RA sera. Anti,cyclic citrullinated peptide antibodies were purified by affinity chromatography and tested on a panel of in vitro deiminated proteins. Their ability to bind in vivo deiminated proteins was evaluated by immunoprecipitation, using EBV-infected cell lines. Results Antibodies specific for a peptide corresponding to the EBNA-135,58 sequence containing citrulline in place of arginine (viral citrullinated peptide [VCP]) were detected in 50% of RA sera and in <5% of normal and disease control sera. In addition, affinity-purified anti-VCP antibodies from RA sera reacted with filaggrin-derived citrullinated peptides, with deiminated fibrinogen, and with deiminated recombinant EBNA-1. Moreover, anti-VCP antibodies immunoprecipitated, from the lysate of calcium ionophore,stimulated lymphoblastoid cell lines, an 80-kd band that was reactive with a monoclonal anti,EBNA-1 antibody and with anti,modified citrulline antibodies. Conclusion These data indicate that ACPAs react with a viral deiminated protein and suggest that EBV infection may play a role in the induction of these RA-specific antibodies. [source] Gene expression profiling differentiates autism case,controls and phenotypic variants of autism spectrum disorders: evidence for circadian rhythm dysfunction in severe autismAUTISM RESEARCH, Issue 2 2009Valerie W. Hu Abstract Autism spectrum disorders (ASD) are neurodevelopmental disorders characterized by delayed/abnormal language development, deficits in social interaction, repetitive behaviors and restricted interests. The heterogeneity in clinical presentation of ASD, likely due to different etiologies, complicates genetic/biological analyses of these disorders. DNA microarray analyses were conducted on 116 lymphoblastoid cell lines (LCL) from individuals with idiopathic autism who are divided into three phenotypic subgroups according to severity scores from the commonly used Autism Diagnostic Interview-Revised questionnaire and age-matched, nonautistic controls. Statistical analyses of gene expression data from control LCL against that of LCL from ASD probands identify genes for which expression levels are either quantitatively or qualitatively associated with phenotypic severity. Comparison of the significant differentially expressed genes from each subgroup relative to the control group reveals differentially expressed genes unique to each subgroup as well as genes in common across subgroups. Among the findings unique to the most severely affected ASD group are 15 genes that regulate circadian rhythm, which has been shown to have multiple effects on neurological as well as metabolic functions commonly dysregulated in autism. Among the genes common to all three subgroups of ASD are 20 novel genes mostly in putative noncoding regions, which appear to associate with androgen sensitivity and which may underlie the strong 4:1 bias toward affected males. [source] Evidence for cis -acting regulation of ANK3 and CACNA1C gene expressionBIPOLAR DISORDERS, Issue 4 2010Emma M Quinn Quinn EM, Hill M, Anney R, Gill M, Corvin AP, Morris DW. Evidence for cis -acting regulation of ANK3 and CACNA1C gene expression. Bipolar Disord 2010: 12: 440,445. © 2010 The Authors. Journal compilation © 2010 John Wiley & Sons A/S. Objectives:, Genome-wide association studies (GWAS) have identified Ankyrin-G (ANK3) and the ,-1C subunit of the L-type voltage-gated calcium channel (CACNA1C) as susceptibility genes for bipolar disorder. Available biological information on these genes suggests a potential molecular mechanism involving ion channel dysfunction. The associated single nucleotide polymorphisms (SNPs) at ANK3 (rs10994336) and CACNA1C (rs1006737) are both intronic with no obvious impact on gene function. We investigated whether, instead of affecting protein function, these risk variants might impact on gene regulation affecting expression. Methods:, We have done this by testing for allelic expression imbalance (AEI) to identify cis -acting regulatory polymorphisms. Results:, We identified evidence of cis -acting variation at both loci in HapMap Caucasian Europeans from Utah (CEU) lymphoblastoid cell lines. There was considerable evidence of AEI at ANK3 with more than half of all heterozygous samples (21 out of 34) for marker SNP rs3750800 showing AEI and a small number of samples showing near monoallelic expression. The AEI at either gene could not be attributed to the GWAS-associated SNPs. Conclusions:, These data indicate that there is genetic variation local to both genes affecting their expression, but that this variation is not responsible for increasing risk of bipolar disorder. [source] The HIV protease inhibitor ritonavir synergizes with butyrate for induction of apoptotic cell death and mediates expression of heme oxygenase-1 in DLD-1 colon carcinoma cellsBRITISH JOURNAL OF PHARMACOLOGY, Issue 7 2004Heiko Mühl The protease inhibitor ritonavir is an integral part of current antiretroviral therapy targeting human immunodeficiency virus. Recent studies demonstrate that ritonavir induces apoptotic cell death with high efficiency in lymphoblastoid cell lines. Moreover, ritonavir can suppress activation of the transcription factor nuclear factor- ,B and is an inhibitor of interleukin-1, and tumor necrosis factor- , production in peripheral blood mononuclear cells. Thus, ritonavir appears to have anti-inflammatory properties. In the present study, we investigated in DLD-1 colon carcinoma cell effects of ritonavir on apoptotic cell death and expression of heme oxygenase-1 (HO-1), an anti-inflammatory enzyme that may be critically involved in the modulation of colonic inflammation. Compared to unstimulated control, ritonavir resulted in a moderate increase in the rate of apoptotic cell death as observed after 20 h of incubation. Notably, ritonavir potently synergized with the short-chain fatty acid butyrate for induction of caspase-3-dependent apoptosis in DLD-1 cells. Ritonavir enhanced mRNA and protein expression of HO-1 in DLD-1 cells. Ritonavir-induced HO-1 protein was suppressed by SB203580 or SB202190 and preceded by immediate upregulation of cellular c-Fos and c-Jun protein levels. This process was associated with induction of activator protein-1 as detected by electrophoretic mobility shift analysis. The present data suggest that ritonavir has the potential to curb colon carcinogenesis by reducing cell growth via mechanisms that include apoptosis and by simultaneously modulating colonic inflammation via induction of anti-inflammatory HO-1. British Journal of Pharmacology (2004) 143, 890,898. doi:10.1038/sj.bjp.0706023 [source] X-Irradiation Induces Up-regulation of ATM Gene Expression in Wild-type Lymphoblastoid Cell Lines, but Not in Their Heterozygous or Homozygous Ataxia-telangiectasia CounterpartsCANCER SCIENCE, Issue 6 2001Yuko Hirai Ataxia-telangiectasia (AT) is an autosomal recessive disease. The relevant gene has been cloned and designated ATM. We studied the expression of both ATM mRNA and the ATM protein in unirradi-ated and X-irradiated EBV (Epstein-Barr virus)-transformed lymphoblastoid cell lines (LCLs) derived from donors who were normal (ATM+/+), AT heterozygotes (ATM+/,), or AT homozy-gotes (ATM,/,), respectively. In ATM+/+ LCLs, the levels of ATM mRNA were found to have increased by approximately 1.5-fold within 1 h of exposure to 10 Gy of X-rays, while the ATM protein levels had increased by 1.5- to 2.0-fold within 2 to 3 h of irradiation. The wild-type mRNA and protein levels both returned to their basal values fairly quickly after this tune. The results obtained with the ATM+/, LCLs were quite different, however: neither the mRNA nor protein levels were found to have increased as a consequence of X-irradiation in any ATM+/, LCL. Twelve of the mutations in the ATM,/, LCLs we used were truncating mutations, and we suspected that the corresponding truncated ATM proteins would be too labile to be detected by western blot analysis. However, five of the ATM,/, LCLs produced mutant ATM proteins that were identical in molecular weight to the wild-type ATM protein. When cells from three of these five clones were exposed to X-rays, transcription of the mutant ATM genes appeared to reduce somewhat, as were the levels of protein being produced. These results suggest that the normal ATM gene responds to ionizing radiation by up-regulating its activity, whereas none of the mutant ATM genes we studied were able to respond in this way. [source] Capacity of robot handling for Epstein-Barr virus transformationCELL PROLIFERATION, Issue 1 2009I.-C. Chang Objectives:, Epstein-Barr virus (EBV) transformation has been described as a routine method to establish human B lymphoblastoid cell lines. Each established lymphoblastoid cell line represents one unique genetic information carrier and can produce unlimited quantities of DNA materials available for downstream applications and research. Undoubtedly, it is of great value to human clinical and experimental genetic studies. However, the current process of EBV transformation requires much manpower in the routine renewal of medium, which is time-consuming. This situation can become a serious problem especially when establishing a human B lymphoblastoid cell bank. A modified and cost-effective protocol for EBV transformation should be considered. Materials and methods:, In the present study, process in EBV transformation was modified to fit the requirements of robot handling. Results:, 1 mL of whole blood was demonstrated to be sufficient to perform EBV transformation. Additionally, EBV transformation can performed in 96-deep-well plates that are directly and widely used with automatic work platforms. Conclusions:, Based on these facts, a process of EBV transformation can be modified to fit the requirements of robot handling. [source] High-potentiality preliminary selection criteria and transformation time-dependent factors analysis for establishing Epstein,Barr virus transformed human lymphoblastoid cell linesCELL PROLIFERATION, Issue 6 2006I.-C. Chang Techniques for optimal infection of the lymphocytes are vital for the establishment of a human biobank. The present study found that more than half (58,86%) of such established LCLs had transport times of less than 48 h, cell densities exceeding 106 cells/ml and cell viabilities greater than 90%. After EBV infection, 3306 freshly isolated lymphocytes required 30.0 ± 0.1 days to become LCLs. Conversely, 1210 cryopreserved lymphocytes required 36.2 ± 0.4 days. Cell density and viability of the culture affected transformation time in freshly isolated lymphocytes. On the other hand, blood transport time, cryopreservation time and initial cell viability were major factors in cryopreserved specimens. These results contribute to general information concerning the establishment of a human biobank for EBV infected cells. [source] G2 -phase radiation response in lymphoblastoid cell lines from Nijmegen breakage syndromeCELL PROLIFERATION, Issue 2 2002A. Antoccia The relationship between G2 -phase checkpoint activation, cytoplasmic cyclin-B1 accumulation and nuclear phosphorylation of p34CDC2 was studied in Nijmegen breakage syndrome cells treated with DNA damaging agents. Experiments were performed on lymphoblastoid cell lines from four Nijmegen breakage syndrome patients with different mutations, as well as on cells from an ataxia telangiectasia patient. Lymphoblastoid cell lines were irradiated with 0.50,2 Gy X-rays and the percentage of G2 -phase accumulated cells was evaluated by means of flow cytometry in samples that were harvested 24 h later. The G2 -checkpoint activation was analysed by scoring the mitotic index at 2 and 4 h after treatment with 0.5 and 1 Gy X-rays and treatment with the DNA double-strand break inducer calicheamicin-,1. Cytoplasmic accumulation of cyclin-B1 was evaluated by means of fluorescence immunostaining or Western blotting, in cells harvested shortly after irradiation with 1 and 2 Gy. The extent of tyrosine 15-phosphorylated p34CDC2 was assessed in the nuclear fractions. Nijmegen breakage syndrome cells showed suboptimal G2 -phase checkpoint activation respect to normal cells and were greatly different from ataxia telangiectasia cells. Increased cytoplasmic cyclin-B1 accumulation was detected by both immunofluorescence and immunoblot in normal as well as in Nijmegen breakage syndrome cells. Furthermore, nuclear p34CDC2. phosphorylation was detected at a higher level in Nijmegen breakage syndrome than in ataxia telangiectasia cells. In conclusion, our data do not suggest that failure to activate checkpoints plays a major role in the radiosensitivity of Nijmegen breakage syndrome cells. [source] Alpha-T-catenin (CTNNA3) gene was identified as a risk variant for toluene diisocyanate-induced asthma by genome-wide association analysisCLINICAL & EXPERIMENTAL ALLERGY, Issue 2 2009S-H. Kim Summary Background Toluene diisocyanate (TDI) is the most important cause of occupational asthma, but the genetic mechanism of TDI-induced asthma is still unknown. Objective The objective of the study was to identify susceptibility alleles associated with the TDI-induced asthma phenotype. Methods We conducted a genome-wide association study in 84 patients with TDI-induced asthma and 263 unexposed healthy normal controls using Affymetrix 500K SNPchip. We also investigated the relationships between genetic polymorphisms and transcript levels in Epstein,Barr virus-transformed lymphoblastoid cell lines from patients with TDI-induced asthma enrolled in this study. Results Genetic polymorphisms of CTNNA3 (catenin alpha 3, alpha-T catenin) were significantly associated with the TDI-induced asthma phenotype (5.84 × 10,6 for rs10762058, 1.41 × 10,5 for rs7088181, 2.03 × 10,5 for rs4378283). Carriers with the minor haplotype, HT2 [GG], of two genetic polymorphisms (rs10762058 and rs7088181) showed significantly lower PC20 methacholine level (P=0.041) and lower mRNA expression of CTNNA3 than non-carriers (P=0.040). A genetic polymorphism in the 3, downstream region of CTNNA3 (rs1786929), as identified by DNA direct sequencing, was significantly associated with the TDI-induced asthma phenotype (P=0.015 in recessive analysis model) and the prevalence of serum-specific IgG to cytokeratin 19 (P=0.031). Conclusion These findings suggested that multiple genetic polymorphisms of CTNNA3 may be determinants of susceptibility to TDI-induced asthma. [source] | |||||||||||||||||||||||||