Changes in gene expression following androgen receptor blockade ...

Indian Academy of Sciences (India)

Madhu urs

of gene expression in the ventral prostate, it is not clear whether all the gene expression ... These include clusterin, methionine adenosyl transferase IIα, and prostate-specific ..... MAGEE1 melanoma antigen and no similarity was found with the ...

Cloning and expression of the Legionella micdadei "common antigen" in Escherichia coli

DEFF Research Database (Denmark)

Bangsborg, Jette Marie; Collins, M T; Høiby, N

1989-01-01

To study individual Legionella antigens, a Legionella micdadei genomic library in Escherichia coli SC181 was established. Partially Sau3A digested L. micdadei DNA fragments (15-25 kilobase pairs (kb] were cloned into the tetracycline resistance gene of the cosmid vector pHC79. Four thousand...... ampicillin resistant recombinants were obtained; seven hundred were screened for expression of Legionella antigens in Western blot analysis with a polyspecific E. coli-absorbed anti-L. micdadei rabbit antibody. One of the positive clones expressed a 60 kilodalton (K) antigen, which reacted strongly...... will provide important information with respect to genetic vs. antigenic relatedness among Legionellae and other Gram-negative species, as well as to CA structure and possible function....

[Expression changes of major outer membrane protein antigens in Leptospira interrogans during infection and its mechanism].

Science.gov (United States)

Zheng, Linli; Ge, Yumei; Hu, Weilin; Yan, Jie

2013-03-01

To determine expression changes of major outer membrane protein(OMP) antigens of Leptospira interrogans serogroup Icterohaemorrhagiae serovar Lai strain Lai during infection of human macrophages and its mechanism. OmpR encoding genes and OmpR-related histidine kinase (HK) encoding gene of L.interrogans strain Lai and their functional domains were predicted using bioinformatics technique. mRNA level changes of the leptospiral major OMP-encoding genes before and after infection of human THP-1 macrophages were detected by real-time fluorescence quantitative RT-PCR. Effects of the OmpR-encoding genes and HK-encoding gene on the expression of leptospiral OMPs during infection were determined by HK-peptide antiserum block assay and closantel inhibitive assays. The bioinformatics analysis indicated that LB015 and LB333 were referred to OmpR-encoding genes of the spirochete, while LB014 might act as a OmpR-related HK-encoding gene. After the spirochete infecting THP-1 cells, mRNA levels of leptospiral lipL21, lipL32 and lipL41 genes were rapidly and persistently down-regulated (P Expression levels of L.interrogans strain Lai major OMP antigens present notable changes during infection of human macrophages. There is a group of OmpR-and HK-encoding genes which may play a major role in down-regulation of expression levels of partial OMP antigens during infection.

Correlation of mRNA and protein levels: Cell type-specific gene expression of cluster designation antigens in the prostate

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Deutsch Eric W

2008-05-01

Full Text Available Abstract Background: Expression levels of mRNA and protein by cell types exhibit a range of correlations for different genes. In this study, we compared levels of mRNA abundance for several cluster designation (CD genes determined by gene arrays using magnetic sorted and laser-capture microdissected human prostate cells with levels of expression of the respective CD proteins determined by immunohistochemical staining in the major cell types of the prostate – basal epithelial, luminal epithelial, stromal fibromuscular, and endothelial – and for prostate precursor/stem cells and prostate carcinoma cells. Immunohistochemical stains of prostate tissues from more than 50 patients were scored for informative CD antigen expression and compared with cell-type specific transcriptomes. Results: Concordance between gene and protein expression findings based on 'present' vs. 'absent' calls ranged from 46 to 68%. Correlation of expression levels was poor to moderate (Pearson correlations ranged from 0 to 0.63. Divergence between the two data types was most frequently seen for genes whose array signals exceeded background (> 50 but lacked immunoreactivity by immunostaining. This could be due to multiple factors, e.g. low levels of protein expression, technological sensitivities, sample processing, probe set definition or anatomical origin of tissue and actual biological differences between transcript and protein abundance. Conclusion: Agreement between these two very different methodologies has great implications for their respective use in both molecular studies and clinical trials employing molecular biomarkers.

The MASP family of Trypanosoma cruzi: changes in gene expression and antigenic profile during the acute phase of experimental infection.

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Sara Lopes dos Santos

Full Text Available Trypanosoma cruzi is the etiological agent of Chagas disease, a debilitating illness that affects millions of people in the Americas. A major finding of the T. cruzi genome project was the discovery of a novel multigene family composed of approximately 1,300 genes that encode mucin-associated surface proteins (MASPs. The high level of polymorphism of the MASP family associated with its localization at the surface of infective forms of the parasite suggests that MASP participates in host-parasite interactions. We speculate that the large repertoire of MASP sequences may contribute to the ability of T. cruzi to infect several host cell types and/or participate in host immune evasion mechanisms.By sequencing seven cDNA libraries, we analyzed the MASP expression profile in trypomastigotes derived from distinct host cells and after sequential passages in acutely infected mice. Additionally, to investigate the MASP antigenic profile, we performed B-cell epitope prediction on MASP proteins and designed a MASP-specific peptide array with 110 putative epitopes, which was screened with sera from acutely infected mice.We observed differential expression of a few MASP genes between trypomastigotes derived from epithelial and myoblast cell lines. The more pronounced MASP expression changes were observed between bloodstream and tissue-culture trypomastigotes and between bloodstream forms from sequential passages in acutely infected mice. Moreover, we demonstrated that different MASP members were expressed during the acute T. cruzi infection and constitute parasite antigens that are recognized by IgG and IgM antibodies. We also found that distinct MASP peptides could trigger different antibody responses and that the antibody level against a given peptide may vary after sequential passages in mice. We speculate that changes in the large repertoire of MASP antigenic peptides during an infection may contribute to the evasion of host immune responses during the

Ectopic Expression of O Antigen in Bordetella pertussis by a Novel Genomic Integration System.

Science.gov (United States)

Ishigaki, Keisuke; Shinzawa, Naoaki; Nishikawa, Sayaka; Suzuki, Koichiro; Fukui-Miyazaki, Aya; Horiguchi, Yasuhiko

2018-01-01

We describe a novel genome integration system that enables the introduction of DNA fragments as large as 50 kbp into the chromosomes of recipient bacteria. This system, named BPI, comprises a bacterial artificial chromosome vector and phage-derived gene integration machinery. We introduced the wbm locus of Bordetella bronchiseptica , which is required for O antigen biosynthesis, into the chromosome of B. pertussis , which intrinsically lacks O antigen, using the BPI system. After the introduction of the wbm locus, B. pertussis presented an additional substance in the lipooligosaccharide fraction that was specifically recognized by the anti- B. bronchiseptica antibody but not the anti- B. pertussis antibody, indicating that B. pertussis expressed O antigen corresponding to that of B. bronchiseptica . O antigen-expressing B. pertussis was less sensitive to the bactericidal effects of serum and polymyxin B than the isogenic parental strain. In addition, an in vivo competitive infection assay showed that O antigen-expressing B. pertussis dominantly colonized the mouse respiratory tract over the parental strain. These results indicate that the BPI system provides a means to alter the phenotypes of bacteria by introducing large exogenous DNA fragments. IMPORTANCE Some bacterial phenotypes emerge through the cooperative functions of a number of genes residing within a large genetic locus. To transfer the phenotype of one bacterium to another, a means to introduce the large genetic locus into the recipient bacterium is needed. Therefore, we developed a novel system by combining the advantages of a bacterial artificial chromosome vector and phage-derived gene integration machinery. In this study, we succeeded for the first time in introducing a gene locus involved in O antigen biosynthesis of Bordetella bronchiseptica into the chromosome of B. pertussis , which intrinsically lacks O antigen, and using this system we analyzed phenotypic alterations in the resultant

Effect of radiation on the expression of carcinoembryonic antigen of human gastric adenocarcinoma cells

Energy Technology Data Exchange (ETDEWEB)

Hareyama, M.; Imai, K.; Kubo, K.; Takahashi, H.; Koshiba, H.; Hinoda, Y.; Shidou, M.; Oouchi, A.; Yachi, A.; Morita, K. (Sapporo Medical College (Japan))

1991-05-01

The changes of antigenic expression of cultured human gastric adenocarcinoma MKN45 cells caused by irradiation were investigated to elucidate the immune responses to localized irradiation. The expression of carcinoembryonic antigen (CEA) showed remarkable increases in the culture supernatant and on the surface of the membrane of irradiated cells. The expression of major histocompatibility complex Class I antigen on the membrane also was enhanced by irradiation. In addition, the irradiated cell groups, when analyzed using a CEA-specific probe, showed remarkable increases in the CEA mRNA. These enhancements increased in the 10-Gy and 15-Gy irradiated populations compared with the 5-Gy irradiated population. These results suggest that the enhancement of expression of CEA by radiation takes place at the CEA gene expression (mRNA) level but not at the protein level.

Count of splenic stromal precursor cells in mice and expression of cytokine genes in these cells in primary cultures during different periods after immunization of animals with S. typhimurium antigens.

Science.gov (United States)

Gorskaya, Yu F; Danilova, T A; Mezentseva, M V; Shapoval, I M; Narovlyanskii, A N; Nesterenko, V G

2011-06-01

Injection of S. typhimurium antigens significantly (9-fold) increased cloning efficiency and, hence, the content of stromal precursor cells in the spleen as soon as after 24 h. These parameters returned to normal by days 6-15 after immunization. Cultured splenocytes collected from immune (but not intact) animals expressed the genes of proinflammatory cytokines IL-1β (on days 1, 6, 15) and IL-6 (on days 1 and 6), TNF-α (on days 6 and 15), and of IFN-α and IL-18 (on days 6 and 15). The expression of IL-4 gene was suppressed on day 6 after immunization, of IL-10 gene on days 1 and 6, of IL-6 gene on day 15. Hence, no signs of immune response suppression by stromal cells were found in this system. The spectrum and dynamics of the expression of pro- and anti-inflammatory cytokine genes in stromal cell cultures from the spleen of immunized mice seemed to correspond to those needed for support of the immune response to S. typhimurium antigens, observed in immunized animals. The results indicate possible involvement of stromal cells in the realization of immune response in vivo. The increase of stromal precursor cells cloning efficiency in response to antigen injection could not be reproduced in vitro: the presence of S. typhimurium antigens in primary cultures of intact mouse bone marrow and spleen throughout the entire period of culturing ≈ 20-fold reduced cloning efficiency in cultures.

Population structuring of multi-copy, antigen-encoding genes in Plasmodium falciparum

Science.gov (United States)

Artzy-Randrup, Yael; Rorick, Mary M; Day, Karen; Chen, Donald; Dobson, Andrew P; Pascual, Mercedes

2012-01-01

The coexistence of multiple independently circulating strains in pathogen populations that undergo sexual recombination is a central question of epidemiology with profound implications for control. An agent-based model is developed that extends earlier ‘strain theory’ by addressing the var gene family of Plasmodium falciparum. The model explicitly considers the extensive diversity of multi-copy genes that undergo antigenic variation via sequential, mutually exclusive expression. It tracks the dynamics of all unique var repertoires in a population of hosts, and shows that even under high levels of sexual recombination, strain competition mediated through cross-immunity structures the parasite population into a subset of coexisting dominant repertoires of var genes whose degree of antigenic overlap depends on transmission intensity. Empirical comparison of patterns of genetic variation at antigenic and neutral sites supports this role for immune selection in structuring parasite diversity. DOI: http://dx.doi.org/10.7554/eLife.00093.001 PMID:23251784

Adoptive Immunotherapy for Hematological Malignancies Using T Cells Gene-Modified to Express Tumor Antigen-Specific Receptors

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Hiroshi Fujiwara

2014-12-01

Full Text Available Accumulating clinical evidence suggests that adoptive T-cell immunotherapy could be a promising option for control of cancer; evident examples include the graft-vs-leukemia effect mediated by donor lymphocyte infusion (DLI and therapeutic infusion of ex vivo-expanded tumor-infiltrating lymphocytes (TIL for melanoma. Currently, along with advances in synthetic immunology, gene-modified T cells retargeted to defined tumor antigens have been introduced as “cellular drugs”. As the functional properties of the adoptive immune response mediated by T lymphocytes are decisively regulated by their T-cell receptors (TCRs, transfer of genes encoding target antigen-specific receptors should enable polyclonal T cells to be uniformly redirected toward cancer cells. Clinically, anticancer adoptive immunotherapy using genetically engineered T cells has an impressive track record. Notable examples include the dramatic benefit of chimeric antigen receptor (CAR gene-modified T cells redirected towards CD19 in patients with B-cell malignancy, and the encouraging results obtained with TCR gene-modified T cells redirected towards NY-ESO-1, a cancer-testis antigen, in patients with advanced melanoma and synovial cell sarcoma. This article overviews the current status of this treatment option, and discusses challenging issues that still restrain the full effectiveness of this strategy, especially in the context of hematological malignancy.

Molecular characteristics of an immobilization antigen gene of the fish-parasitic protozoan Ichthyophthirius multifiliis strain ARS-6

Science.gov (United States)

Ichthyophthirius multifiliis, a ciliated protozoan parasite of fish, expresses surface antigens (i-antigens), which react with host antibodies that render them immobile. The nucleotide sequence of an i-antigen gene of Ichthyophthirius multifiliis strain ARS-6 was deduced. The predicted protein of 47...

Microarray Gene Expression Analysis to Evaluate Cell Type Specific Expression of Targets Relevant for Immunotherapy of Hematological Malignancies.

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M J Pont

Full Text Available Cellular immunotherapy has proven to be effective in the treatment of hematological cancers by donor lymphocyte infusion after allogeneic hematopoietic stem cell transplantation and more recently by targeted therapy with chimeric antigen or T-cell receptor-engineered T cells. However, dependent on the tissue distribution of the antigens that are targeted, anti-tumor responses can be accompanied by undesired side effects. Therefore, detailed tissue distribution analysis is essential to estimate potential efficacy and toxicity of candidate targets for immunotherapy of hematological malignancies. We performed microarray gene expression analysis of hematological malignancies of different origins, healthy hematopoietic cells and various non-hematopoietic cell types from organs that are often targeted in detrimental immune responses after allogeneic stem cell transplantation leading to graft-versus-host disease. Non-hematopoietic cells were also cultured in the presence of IFN-γ to analyze gene expression under inflammatory circumstances. Gene expression was investigated by Illumina HT12.0 microarrays and quality control analysis was performed to confirm the cell-type origin and exclude contamination of non-hematopoietic cell samples with peripheral blood cells. Microarray data were validated by quantitative RT-PCR showing strong correlations between both platforms. Detailed gene expression profiles were generated for various minor histocompatibility antigens and B-cell surface antigens to illustrate the value of the microarray dataset to estimate efficacy and toxicity of candidate targets for immunotherapy. In conclusion, our microarray database provides a relevant platform to analyze and select candidate antigens with hematopoietic (lineage-restricted expression as potential targets for immunotherapy of hematological cancers.

Codon optimisation to improve expression of a Mycobacterium avium ssp. paratuberculosis-specific membrane-associated antigen by Lactobacillus salivarius.

Science.gov (United States)

Johnston, Christopher; Douarre, Pierre E; Soulimane, Tewfik; Pletzer, Daniel; Weingart, Helge; MacSharry, John; Coffey, Aidan; Sleator, Roy D; O'Mahony, Jim

2013-06-01

Subunit and DNA-based vaccines against Mycobacterium avium ssp. paratuberculosis (MAP) attempt to overcome inherent issues associated with whole-cell formulations. However, these vaccines can be hampered by poor expression of recombinant antigens from a number of disparate hosts. The high G+C content of MAP invariably leads to a codon bias throughout gene expression. To investigate if the codon bias affects recombinant MAP antigen expression, the open reading frame of a MAP-specific antigen MptD (MAP3733c) was codon optimised for expression against a Lactobacillus salivarius host. Of the total 209 codons which constitute MAP3733c, 172 were modified resulting in a reduced G+C content from 61% for the native gene to 32.7% for the modified form. Both genes were placed under the transcriptional control of the PnisA promoter; allowing controlled heterologous expression in L. salivarius. Expression was monitored using fluorescence microscopy and microplate fluorometry via GFP tags translationally fused to the C-termini of the two MptD genes. A > 37-fold increase in expression was observed for the codon-optimised MAP3733synth variant over the native gene. Due to the low cost and improved expression achieved, codon optimisation significantly improves the potential of L. salivarius as an oral vaccine stratagem against Johne's disease. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

Paired Expression Analysis of Tumor Cell Surface Antigens

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Rimas J. Orentas

2017-08-01

Full Text Available Adoptive immunotherapy with antibody-based therapy or with T cells transduced to express chimeric antigen receptors (CARs is useful to the extent that the cell surface membrane protein being targeted is not expressed on normal tissues. The most successful CAR-based (anti-CD19 or antibody-based therapy (anti-CD20 in hematologic malignancies has the side effect of eliminating the normal B cell compartment. Targeting solid tumors may not provide a similar expendable marker. Beyond antibody to Her2/NEU and EGFR, very few antibody-based and no CAR-based therapies have seen broad clinical application for solid tumors. To expand the way in which the surfaceome of solid tumors can be analyzed, we created an algorithm that defines the pairwise relative overexpression of surface antigens. This enables the development of specific immunotherapies that require the expression of two discrete antigens on the surface of the tumor target. This dyad analysis was facilitated by employing the Hotelling’s T-squared test (Hotelling–Lawley multivariate analysis of variance for two independent variables in comparison to a third constant entity (i.e., gene expression levels in normal tissues. We also present a unique consensus scoring mechanism for identifying transcripts that encode cell surface proteins. The unique application of our bioinformatics processing pipeline and statistical tools allowed us to compare the expression of two membrane protein targets as a pair, and to propose a new strategy based on implementing immunotherapies that require both antigens to be expressed on the tumor cell surface to trigger therapeutic effector mechanisms. Specifically, we found that, for MYCN amplified neuroblastoma, pairwise expression of ACVR2B or anaplastic lymphoma kinase (ALK with GFRA3, GFRA2, Cadherin 24, or with one another provided the strongest hits. For MYCN, non-amplified stage 4 neuroblastoma, neurotrophic tyrosine kinase 1, or ALK paired with GFRA2, GFRA3, SSK

Expressed var gene repertoire and variant surface antigen diversity in a shrinking Plasmodium falciparum population.

Science.gov (United States)

Carlos, Bianca C; Fotoran, Wesley L; Menezes, Maria J; Cabral, Fernanda J; Bastos, Marcele F; Costa, Fabio T M; Sousa-Neto, Jayme A; Ribolla, Paulo E M; Wunderlich, Gerhard; Ferreira, Marcelo U

2016-11-01

The var gene-encoded erythrocyte membrane protein-1 of Plasmodium falciparum (PfEMP-1) is the main variant surface antigen (VSA) expressed on infected erythrocytes. The rate at which antibody responses to VSA expressed by circulating parasites are acquired depends on the size of the local VSA repertoire and the frequency of exposure to new VSA. Because parasites from areas with declining malaria endemicity, such as the Amazon, typically express a restricted PfEMP-1 repertoire, we hypothesized that Amazonians would rapidly acquire antibodies to most locally circulating VSA. Consistent with our expectations, the analysis of 5878 sequence tags expressed by 10 local P. falciparum samples revealed little PfEMP-1 DBL1α domain diversity. Among the most commonly expressed DBL1α types, 45% were shared by two or more independent parasite lines. Nevertheless, Amazonians displayed major gaps in their repertoire of anti-VSA antibodies, although the breadth of anti-VSA antibody responses correlated positively with their cumulative exposure to malaria. We found little antibody cross-reactivity even when testing VSA from related parasites expressing the same dominant DBL1α types. We conclude that variant-specific immunity to P. falciparum VSAs develops slowly despite the relatively restricted PfEMP-1 repertoire found in low-endemicity settings. Copyright © 2016 Elsevier Inc. All rights reserved.

Construction, expression, purification and biotin labeling of a single recombinant multi-epitope antigen for double-antigen sandwich ELISA to detect hepatitis C virus antibody.

Science.gov (United States)

He, Jing; Xiu, Bingshui; Wang, Guohua; Chen, Kun; Feng, Xiaoyan; Song, Xiaoguo; Zhu, Cuixia; Yang, Xiqin; Bai, Guanzhong; Ling, Shigan; Zhang, Heqiu

2011-08-01

Based on B cell epitope predictions, a recombinant antigen with multiple epitopes from four Hepatitis C Virus fragments (C, NS3, NS4 and NS5) were engineered. The recombinant gene was then highly expressed in E. coli. The non-modified and C-terminal-modified recombinant proteins were used for coating and biotin labeling, respectively, to establish the double-antigen sandwich ELISA. Ten positive reference samples confirmed by the CHIRON RIBA HCV 3.0 SIA kit were detected positive, Forty one plasma samples were positive among samples from 441 volunteers, which indicated that the recombinant antigen could readily react well with plasma HCV antibody. As critical reagents of double-antigen sandwich ELISA, the recombinant multi-epitope antigen and the C-terminal-modified and biotin-conjugated antigen show good antigenicity. In this study, we provide a simple approach to produce multiple epitopes within one recombinant protein in order to avoid the costly expression of less-effective pools of multiple proteins, which is the conventional strategy of diagnostic antigen production for HCV antibody detection.

[Expression, purification and protective antigen analysis of cell wall protein MRP of Streptococcus suis type 2].

Science.gov (United States)

Wang, Ping-ping; Pian, Ya-ya; Yuan, Yuan; Zheng, Yu-ling; Jiang, Yong-qiang; Xiong, Zheng-ying

2012-02-01

To amplify the mrp gene of Streptococcus suis type 2 05ZYH33, express it in E.coli BL21 in order to acquire high purity recombinant protein MRP, then evaluate the protective antigen of recombinant protein MRP. Using PCR technology to obtain the product of mrp gene of 05ZYH33, and then cloned it into the expression vector pET28a(+). The recombinant protein was purified by affinity chromatography, later immunized New Zealand rabbit to gain anti-serum, then test the anti-serum titer by ELISA. The opsonophagocytic killing test demonstrated the abilities of protective antigen of MRP. The truncated of MRP recombinant protein in E.coli BL21 expressed by inclusion bodies, and purified it in high purity. After immunoprotection, the survival condition of CD-1 was significantly elevated. The survival rate of wild-type strain 05ZYH33 in blood was apparently decreased after anti-serum opsonophagocyticed, but the mutant delta; MRP showed no differences. MRP represent an important protective antigen activity.

Real-time PCR analysis of genes encoding tumor antigens in esophageal tumors and a cancer vaccine

NARCIS (Netherlands)

Weinert, Brian T.; Krishnadath, Kausilia K.; Milano, Francesca; Pedersen, Ayako W.; Claesson, Mogens H.; Zocca, Mai-Britt

2009-01-01

Tumor antigens are the primary target of therapeutic cancer vaccines. We set out to define and compare the expression pattern of tumor antigen genes in esophagus carcinoma biopsies and in an allogeneic tumor lysate-based cancer vaccine, MelCancerVac. Cells used for vaccine production were treated

Recombinant carcinoembryonic antigen as a reporter gene for molecular imaging

International Nuclear Information System (INIS)

Kenanova, Vania; Barat, Bhaswati; Olafsen, Tove; Chatziioannou, Arion; Herschman, Harvey R.; Wu, Anna M.; Braun, Jonathan

2009-01-01

Reporter genes can provide a way of noninvasively assessing gene activity in vivo. However, current reporter gene strategies may be limited by the immunogenicity of foreign reporter proteins, endogenous expression, or unwanted biological activity. We have developed a reporter gene based on carcinoembryonic antigen (CEA), a human protein with limited normal tissue expression. To construct a CEA reporter gene for PET, a CEA minigene (N-A3) was fused to the extracellular and transmembrane domains of the human FcγRIIb receptor. The NA3-FcγRIIb recombinant gene, driven by a CMV promoter, was transfected in Jurkat (human T cell leukemia) cells. Expression was analyzed by flow cytometry, immunohistochemistry (IHC), and microPET imaging. Flow cytometry identified Jurkat clones stably expressing NA3-FcγRIIb at low, medium, and high levels. High and medium NA3-FcγRIIb expression could also be detected by Western blot. Reporter gene positive and negative Jurkat cells were used to establish xenografts in athymic mice. IHC showed staining of the tumor with high reporter gene expression; medium and low N-A3 expression was not detected. MicroPET imaging, using an anti-CEA 124 I-labeled single-chain Fv-Fc antibody fragment, demonstrated that only high N-A3 expression could be detected. Specific accumulation of activity was visualized at the N-A3 positive tumor as early as 4 h. MicroPET image quantitation showed tumor activity of 1.8 ± 0.2, 15.2 ± 1.3, and 4.6 ± 1.2 percent injected dose per gram (%ID/g) at 4, 20, and 48 h, respectively. Biodistribution at 48 h demonstrated tumor uptake of 4.8 ± 0.8%ID/g. The CEA N-A3 minigene has the potential to be used as a reporter gene for imaging cells in vivo. (orig.)

PRAME gene expression profile in medulloblastoma

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Tânia Maria Vulcani-Freitas

2011-02-01

Full Text Available Medulloblastoma is the most common malignant tumors of central nervous system in the childhood. The treatment is severe, harmful and, thus, has a dismal prognosis. As PRAME is present in various cancers, including meduloblastoma, and has limited expression in normal tissues, this antigen can be an ideal vaccine target for tumor immunotherapy. In order to find a potential molecular target, we investigated PRAME expression in medulloblastoma fragments and we compare the results with the clinical features of each patient. Analysis of gene expression was performed by real-time quantitative PCR from 37 tumor samples. The Mann-Whitney test was used to analysis the relationship between gene expression and clinical characteristics. Kaplan-Meier curves were used to evaluate survival. PRAME was overexpressed in 84% samples. But no statistical association was found between clinical features and PRAME overexpression. Despite that PRAME gene could be a strong candidate for immunotherapy since it is highly expressed in medulloblastomas.

Erasing the Epigenetic Memory and Beginning to Switch—The Onset of Antigenic Switching of var Genes in Plasmodium falciparum

Science.gov (United States)

Fastman, Yair; Noble, Robert; Recker, Mario; Dzikowski, Ron

2012-01-01

Antigenic variation in Plasmodium falciparum is regulated by transcriptional switches among members of the var gene family, each expressed in a mutually exclusive manner and encoding a different variant of the surface antigens collectively named PfEMP1. Antigenic switching starts when the first merozoites egress from the liver and begin their asexual proliferation within red blood cells. By erasing the epigenetic memory we created parasites with no var background, similar to merozoites that egress from the liver where no var gene is expressed. Creating a null-var background enabled us to investigate the onset of antigenic switches at the early phase of infection. At the onset of switching, var transcription pattern is heterogeneous with numerous genes transcribed at low levels including upsA vars, a subtype that was implicated in severe malaria, which are rarely activated in growing cultures. Analysis of subsequent in vitro switches shows that the probability of a gene to turn on or off is not associated with its chromosomal position or promoter type per se but on intrinsic properties of each gene. We concluded that var switching is determined by gene specific associated switch rates rather than general promoter type or locus associated switch rates. In addition, we show that fine tuned reduction in var transcription increases their switch rate, indicating that transcriptional perturbation can alter antigenic switching. PMID:22461905

Age-Associated Decline in Thymic B Cell Expression of Aire and Aire-Dependent Self-Antigens

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Sergio Cepeda

2018-01-01

Full Text Available Although autoimmune disorders are a significant source of morbidity and mortality in older individuals, the mechanisms governing age-associated increases in susceptibility remain incompletely understood. Central T cell tolerance is mediated through presentation of self-antigens by cells constituting the thymic microenvironment, including epithelial cells, dendritic cells, and B cells. Medullary thymic epithelial cells (mTECs and B cells express distinct cohorts of self-antigens, including tissue-restricted self-antigens (TRAs, such that developing T cells are tolerized to antigens from peripheral tissues. We find that expression of the TRA transcriptional regulator Aire, as well as Aire-dependent genes, declines with age in thymic B cells in mice and humans and that cell-intrinsic and cell-extrinsic mechanisms contribute to the diminished capacity of peripheral B cells to express Aire within the thymus. Our findings indicate that aging may diminish the ability of thymic B cells to tolerize T cells, revealing a potential mechanistic link between aging and autoimmunity.

Expression of cancer-testis antigens MAGE-A4 and MAGE-C1 in oral squamous cell carcinoma.

Science.gov (United States)

Montoro, José Raphael de Moura Campos; Mamede, Rui Celso Martins; Neder Serafini, Luciano; Saggioro, Fabiano Pinto; Figueiredo, David Livingstone Alves; Silva, Wilson Araújo da; Jungbluth, Achim A; Spagnoli, Giulio Cesare; Zago, Marco Antônio

2012-08-01

Tumor markers are genes or their products expressed exclusively or preferentially in tumor cells and cancer-testis antigens (CTAs) form a group of genes with a typical expression pattern expressed in a variety of malignant neoplasms. CTAs are considered potential targets for cancer vaccines. It is possible that the CTA MAGE-A4 (melanoma antigen) and MAGE-C1 are expressed in carcinoma of the oral cavity and are related with survival. This study involved immunohistochemical analysis of 23 patients with oral squamous cell carcinoma (SCC) and was carried out using antibodies for MAGE-A4 and MAGE-C1. Fisher's exact test and log-rank test were used to evaluate the results. The expression of the MAGE-A4 and MAGE-C1 were 56.5% and 47.8% without statistical difference in studied variables and survival. The expression of at least 1 CTA was present in 78.3% of the patients, however, without correlation with clinicopathologic variables and survival. Copyright © 2011 Wiley Periodicals, Inc.

Plasmodium knowlesi Sporozoite Antigen: Expression by Infectious Recombinant Vaccinia Virus

Science.gov (United States)

Smith, Geoffrey L.; Godson, G. Nigel; Nussenzweig, Victor; Nussenzweig, Ruth S.; Barnwell, John; Moss, Bernard

1984-04-01

The gene coding for the circumsporozoite antigen of the malaria parasite Plasmodium knowlesi was inserted into the vaccinia virus genome under the control of a defined vaccinia virus promoter. Cells infected with the recombinant virus synthesized polypeptides of 53,000 to 56,000 daltons that reacted with monoclonal antibody against the repeating epitope of the malaria protein. Furthermore, rabbits vaccinated with the recombinant virus produced antibodies that bound specifically to sporozoites. These data provide evidence for expression of a cloned malaria gene in mammalian cells and illustrate the potential of vaccinia virus recombinants as live malaria vaccines.

Epigenetic modulation of cancer-germline antigen gene expression in tumorigenic human mesenchymal stem cells: implications for cancer therapy

DEFF Research Database (Denmark)

Gjerstorff, Morten; Burns, Jorge S; Nielsen, Ole

2009-01-01

Cancer-germline antigens are promising targets for cancer immunotherapy, but whether such therapies will also eliminate the primary tumor stem cell population remains undetermined. We previously showed that long-term cultures of telomerized adult human bone marrow mesenchymal stem cells can...... spontaneously evolve into tumor-initiating, mesenchymal stem cells (hMSC-TERT20), which have characteristics of clinical sarcoma cells. In this study, we used the hMSC-TERT20 tumor stem cell model to investigate the potential of cancer-germline antigens to serve as tumor stem cell targets. We found...... of cancer-germline antigens in hMSC-TERT20 cells, while their expression levels in primary human mesenchymal stem cells remained unaffected. The expression pattern of cancer-germline antigens in tumorigenic mesenchymal stem cells and sarcomas, plus their susceptibility to enhancement by epigenetic...

Abnormal expression of blood group-related antigens in uterine endometrial cancers.

Science.gov (United States)

Tsukazaki, K; Sakayori, M; Arai, H; Yamaoka, K; Kurihara, S; Nozawa, S

1991-08-01

The expression of A, B, and H group antigens, Lewis group antigens (Lewis(a), Lewis(b), Lewis(x), and Lewis(y)), and Lc4 and nLc4 antigens, the precursor antigens of both groups, was examined immunohistochemically with monoclonal antibodies in 9 normal endometria, 6 endometrial hyperplasias, and 31 endometrial cancers. 1) A, B and/or H antigens were detected in endometrial cancers at an incidence of 51.6%, while no distinct localization of these antigens was observed in normal endometria. H antigen, the precursor of A and B antigens, was particularly frequently detected in endometrial cancers. 2) An increased rate of expression of Lewis group antigens, particularly Lewis(b) antigen, was observed in endometrial cancers compared with its expression in normal endometria. 3) Lc4 and nLc4 antigens were detected in endometrial cancers at rates of 41.9% and 38.7%, respectively, these expressions being increased compared with those in normal endometria. 4) These results suggest that a highly abnormal expression of blood group-related antigens in endometrial cancers occurs not only at the level of A, B, and H antigens and Lewis group antigens, but also at the level of their precursor Lc4 and nLc4 antigens. 5) Lewis(a), Lewis(b), and Lc4 antigens, built on the type-1 chain, are more specific to endometrial cancers than their respective positional isomers, Lewis(x), Lewis(y), and nLc4 antigens, built on the type-2 chain.

In Vitro Variant Surface Antigen Expression in Plasmodium falciparum Parasites from a Semi-Immune Individual Is Not Correlated with Var Gene Transcription

Science.gov (United States)

Tschan, Serena; Flötenmeyer, Matthias; Koch, Iris; Berger, Jürgen; Kremsner, Peter; Frank, Matthias

2016-01-01

Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) is considered to be the main variant surface antigen (VSA) of Plasmodium falciparum and is mainly localized on electron-dense knobs in the membrane of the infected erythrocyte. Switches in PfEMP1 expression provide the basis for antigenic variation and are thought to be critical for parasite persistence during chronic infections. Recently, strain transcending anti-PfEMP1 immunity has been shown to develop early in life, challenging the role of PfEMP1 in antigenic variation during chronic infections. In this work we investigate how P. falciparum achieves persistence during a chronic asymptomatic infection. The infected individual (MOA) was parasitemic for 42 days and multilocus var gene genotyping showed persistence of the same parasite population throughout the infection. Parasites from the beginning of the infection were adapted to tissue culture and cloned by limiting dilution. Flow cytometry using convalescent serum detected a variable surface recognition signal on isogenic clonal parasites. Quantitative real-time PCR with a field isolate specific var gene primer set showed that the surface recognition signal was not correlated with transcription of individual var genes. Strain transcending anti-PfEMP1 immunity of the convalescent serum was demonstrated with CD36 selected and PfEMP1 knock-down NF54 clones. In contrast, knock-down of PfEMP1 did not have an effect on the antibody recognition signal in MOA clones. Trypsinisation of the membrane surface proteins abolished the surface recognition signal and immune electron microscopy revealed that antibodies from the convalescent serum bound to membrane areas without knobs and with knobs. Together the data indicate that PfEMP1 is not the main variable surface antigen during a chronic infection and suggest a role for trypsin sensitive non-PfEMP1 VSAs for parasite persistence in chronic infections. PMID:27907004

Differentiation of EL4 lymphoma cells by tumoral environment is associated with inappropriate expression of the large chondroitin sulfate proteoglycan PG-M and the tumor-associated antigen HTgp-175.

Science.gov (United States)

Rottiers, P; Verfaillie, T; Contreras, R; Revets, H; Desmedt, M; Dooms, H; Fiers, W; Grooten, J

1998-11-09

Progression to malignancy of transformed cells involves complex genetic alterations and aberrant gene expression patterns. While aberrant gene expression is often caused by alterations in individual genes, the contribution of the tumoral environment to the triggering of this gene expression is less well established. The stable but heterogeneous expression in cultured EL4/13 cells of a novel tumor-associated antigen, designated as HTgp-175, was chosen for the investigation of gene expression during tumor formation. Homogeneously HTgp-175-negative EL4/13 cells, isolated by cell sorting or obtained by subcloning, acquired HTgp-175 expression as a result of tumor formation. The tumorigenicity of HTgp-175-negative vs. HTgp-175-positive EL4 variants was identical, indicating that induction but not selection accounted for the phenotypic switch from HTgp-175-negative to HTgp-175-positive. Although mutagenesis experiments showed that the protein was not essential for tumor establishment, tumor-derived cells showed increased malignancy, linking HTgp-175 expression with genetic changes accompanying tumor progression. This novel gene expression was not an isolated event, since it was accompanied by ectopic expression of the large chondroitin sulfate proteoglycan PG-M and of normal differentiation antigens. We conclude that signals derived from the tumoral microenvironment contribute significantly to the aberrant gene expression pattern of malignant cells, apparently by fortuitous activation of differentiation processes and cause expression of novel differentiation antigens as well as of inappropriate tumor-associated and ectopic antigens.

[Eukaryotic expression of Leptospira interrogans lipL32/1-ompL1/1 fusion gene encoding genus-specific protein antigens and the immunoreactivity of expression products].

Science.gov (United States)

Yan, Jie; Zhao, Shou-feng; Mao, Ya-fei; Ruan, Ping; Luo, Yi-hui; Li, Shu-ping; Li, Li-wei

2005-01-01

To construct the eukaryotic expression system of L.interrogans lipL32/1-ompL1/1 fusion gene and to identify the immunoreactivity of expression products. PCR with linking primer was used to construct the fusion gene lipL32/1-ompL1/1. The P.pastoris eukaryotic expression system of the fusion gene, pPIC9K-lipL32/1-ompL1/1-P. pastorisGS115, was constructed after the fusion gene was cloned and sequenced. Colony with phenotype His(+)Mut(+) was isolated by using MD and MM plates and His(+) Mut(+) transformant with high resistance to G418 was screened out by using YPD plate. Using lysate of His(+) Mut(+) colony with high copies of the target gene digested with yeast lyase as the template and 5'AOX1 and 3'AOX1 as the primers, the target fusion gene in chromosome DNA of the constructed P. pastoris engineering strain was detected by PCR. Methanol in BMMY medium was used to induce the target recombinant protein rLipL32/1-rOmpL1/1 expression. rLipL32/1-rOmpL1/1 in the medium supernatant was extracted by using ammonium sulfate precipitation and Ni-NTA affinity chromatography. Output and immunoreactivity of rLipL32/1-rOmpL1/1 were measured by SDS-PAGE and Western blot methods, respectively. Amplification fragments of the obtained fusion gene lipL32/1-ompL1/1 was 1794 bp in size. The homogeneity of nucleotide and putative amino acid sequences of the fusion gene were as high as 99.94 % and 100 %, respectively, compared with the sequences of original lipL32/1 and ompL1/1 genotypes. The constructed eukaryotic expression system was able to secrete rLipL32/1-rOmpL1/1 with an output of 10 % of the total proteins in the supernatant, which located the expected position after SDS-PAGE. The rabbit anti-rLipL32/1 and anti-rOmpL1/1 sera could combine the expressed rLipL32/1-rOmpL1/1. An eukaryotic expression system with high efficiency in P.pastoris of L.interrogans lipL32/1-ompL1/1 fusion gene was successfully constructed in this study. The expressed fusion protein shows specific

Recombinant hepatitis B surface antigen production in Aspergillus niger: evaluating the strategy of gene fusion to native glucoamylase

CSIR Research Space (South Africa)

James, ER

2012-10-01

Full Text Available Microbiology and Biotechnology October 2012/ Vol. 96, No.2 Recombinant hepatitis B surface antigen production in Aspergillus niger: evaluating the strategy of gene fusion to native glucoamylase ER James a,c & WH van Zyl b & PJ van Zyl c & JF Görgens..., Pretoria 0001, South Africa Abstract This study demonstrates the potential of Aspergillus niger as a candidate expression system for virus- like particle production using gene fusion. Hepatitis B surface antigen (HBsAg) production, targeted...

Enhanced Expression of Interferon-γ-Induced Antigen-Processing Machinery Components in a Spontaneously Occurring Cancer

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Fulvia Cerruti

2007-11-01

Full Text Available In human tumors, changes in the surface expression and/or function of major histocompatibility complex (MHC class I antigens are frequently found and may provide malignant cells with a mechanism to escape control of the immune system. This altered human lymphocyte antigen (HLA class I phenotype can be caused by either structural alterations or dysregulation of genes encoding subunits of HLA class I antigens and/or components of the MHC class I antigen-processing machinery (APM. Herein we analyze the expression of several proteins involved in the generation of MHC class I epitopes in feline injection site sarcoma, a spontaneously occurring tumor in cats that is an informative model for the study of tumor biology in other species, including humans. Eighteen surgically removed primary fibrosarcoma lesions were analyzed, and an enhanced expression of two catalytic subunits of immunoproteasomes, PA28 and leucine aminopeptidase, was found in tumors compared to matched normal tissues. As a functional counterpart of these changes in protein levels, proteasomal activities were increased in tissue extracts from fibrosarcomas. Taken together, these results suggest that alterations in the APM system may account for reduced processing of selected tumor antigens and may potentially provide neoplastic fibroblasts with a mechanism for escape from T-cell recognition and destruction.

Characterization of a new Lactobacillus salivarius strain engineered to express IBV multi-epitope antigens by chromosomal integration.

Science.gov (United States)

Ma, Bing-cun; Yang, Xin; Wang, Hong-ning; Cao, Hai-peng; Xu, Peng-wei; Ding, Meng-die; Liu, Hui

2016-01-01

To obtain adhesive and safe lactic acid bacteria (LAB) strains for expressing heterologous antigens, we screened LAB inhabitants in intestine of Tibetan chickens by analyzing their adhesion and safety properties and the selected LAB was engineered to express heterologous antigen (UTEpi C-A) based on chromosomal integration strategy. We demonstrated that a new Lactobacillu salivarius TCMM17 strain is strongly adhesive to chicken intestinal epithelial cells, contains no endogenous plasmids, is susceptible to tested antimicrobials, and shows no toxicities. In order to examine the potential of TCMM17 strain as heterogenous antigen delivering vehicle, we introduced a UTEpi C-A expression cassette in its chromosome by constructing a non-replicative plasmid (pORI280-UUTEpi C-AD). The recombinant TCMM17 strain (∆TCMM17) stably was found to keep the gene cassette through 50 generations, and successfully displayed EpiC encoded by the cassette on its surface. This work provides a universal platform for development of novel oral vaccines and expression of further antigens of avian pathogens.

Alternative haplotypes of antigen processing genes in zebrafish diverged early in vertebrate evolution

Science.gov (United States)

McConnell, Sean C.; Hernandez, Kyle M.; Wcisel, Dustin J.; Kettleborough, Ross N.; Stemple, Derek L.; Andrade, Jorge; de Jong, Jill L. O.

2016-01-01

Antigen processing and presentation genes found within the MHC are among the most highly polymorphic genes of vertebrate genomes, providing populations with diverse immune responses to a wide array of pathogens. Here, we describe transcriptome, exome, and whole-genome sequencing of clonal zebrafish, uncovering the most extensive diversity within the antigen processing and presentation genes of any species yet examined. Our CG2 clonal zebrafish assembly provides genomic context within a remarkably divergent haplotype of the core MHC region on chromosome 19 for six expressed genes not found in the zebrafish reference genome: mhc1uga, proteasome-β 9b (psmb9b), psmb8f, and previously unknown genes psmb13b, tap2d, and tap2e. We identify ancient lineages for Psmb13 within a proteasome branch previously thought to be monomorphic and provide evidence of substantial lineage diversity within each of three major trifurcations of catalytic-type proteasome subunits in vertebrates: Psmb5/Psmb8/Psmb11, Psmb6/Psmb9/Psmb12, and Psmb7/Psmb10/Psmb13. Strikingly, nearby tap2 and MHC class I genes also retain ancient sequence lineages, indicating that alternative lineages may have been preserved throughout the entire MHC pathway since early diversification of the adaptive immune system ∼500 Mya. Furthermore, polymorphisms within the three MHC pathway steps (antigen cleavage, transport, and presentation) are each predicted to alter peptide specificity. Lastly, comparative analysis shows that antigen processing gene diversity is far more extensive than previously realized (with ancient coelacanth psmb8 lineages, shark psmb13, and tap2t and psmb10 outside the teleost MHC), implying distinct immune functions and conserved roles in shaping MHC pathway evolution throughout vertebrates. PMID:27493218

Neural Crest Cells Isolated from the Bone Marrow of Transgenic Mice Express JCV T-Antigen.

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Jennifer Gordon

Full Text Available JC virus (JCV, a common human polyomavirus, is the etiological agent of the demyelinating disease, progressive multifocal leukoencephalopathy (PML. In addition to its role in PML, studies have demonstrated the transforming ability of the JCV early protein, T-antigen, and its association with some human cancers. JCV infection occurs in childhood and latent virus is thought to be maintained within the bone marrow, which harbors cells of hematopoietic and non-hematopoietic lineages. Here we show that non-hematopoietic mesenchymal stem cells (MSCs isolated from the bone marrow of JCV T-antigen transgenic mice give rise to JCV T-antigen positive cells when cultured under neural conditions. JCV T-antigen positive cells exhibited neural crest characteristics and demonstrated p75, SOX-10 and nestin positivity. When cultured in conditions typical for mesenchymal cells, a population of T-antigen negative cells, which did not express neural crest markers arose from the MSCs. JCV T-antigen positive cells could be cultured long-term while maintaining their neural crest characteristics. When these cells were induced to differentiate into neural crest derivatives, JCV T-antigen was downregulated in cells differentiating into bone and maintained in glial cells expressing GFAP and S100. We conclude that JCV T-antigen can be stably expressed within a fraction of bone marrow cells differentiating along the neural crest/glial lineage when cultured in vitro. These findings identify a cell population within the bone marrow permissible for JCV early gene expression suggesting the possibility that these cells could support persistent viral infection and thus provide clues toward understanding the role of the bone marrow in JCV latency and reactivation. Further, our data provides an excellent experimental model system for studying the cell-type specificity of JCV T-antigen expression, the role of bone marrow-derived stem cells in the pathogenesis of JCV-related diseases

The evolutionary dynamics of variant antigen genes in Babesia reveal a history of genomic innovation underlying host-parasite interaction

KAUST Repository

Jackson, Andrew P.

2014-05-05

Babesia spp. are tick-borne, intraerythrocytic hemoparasites that use antigenic variation to resist host immunity, through sequential modification of the parasite-derived variant erythrocyte surface antigen (VESA) expressed on the infected red blood cell surface. We identified the genomic processes driving antigenic diversity in genes encoding VESA (ves1) through comparative analysis within and between three Babesia species, (B. bigemina, B. divergens and B. bovis). Ves1 structure diverges rapidly after speciation, notably through the evolution of shortened forms (ves2) from 5? ends of canonical ves1 genes. Phylogenetic analyses show that ves1 genes are transposed between loci routinely, whereas ves2 genes are not. Similarly, analysis of sequence mosaicism shows that recombination drives variation in ves1 sequences, but less so for ves2, indicating the adoption of different mechanisms for variation of the two families. Proteomic analysis of the B. bigemina PR isolate shows that two dominant VESA1 proteins are expressed in the population, whereas numerous VESA2 proteins are co-expressed, consistent with differential transcriptional regulation of each family. Hence, VESA2 proteins are abundant and previously unrecognized elements of Babesia biology, with evolutionary dynamics consistently different to those of VESA1, suggesting that their functions are distinct. 2014 The Author(s) 2014.

The evolutionary dynamics of variant antigen genes in Babesia reveal a history of genomic innovation underlying host-parasite interaction

KAUST Repository

Jackson, Andrew P.; Otto, Thomas D.; Darby, Alistair; Ramaprasad, Abhinay; Xia, Dong; Echaide, Ignacio Eduardo; Farber, Marisa; Gahlot, Sunayna; Gamble, John; Gupta, Dinesh; Gupta, Yask; Jackson, Louise; Malandrin, Laurence; Malas, Tareq B.; Moussa, Ehab; Nair, Mridul; Reid, Adam J.; Sanders, Mandy; Sharma, Jyotsna; Tracey, Alan; Quail, Mike A.; Weir, William; Wastling, Jonathan M.; Hall, Neil; Willadsen, Peter; Lingelbach, Klaus; Shiels, Brian; Tait, Andy; Berriman, Matt; Allred, David R.; Pain, Arnab

2014-01-01

Babesia spp. are tick-borne, intraerythrocytic hemoparasites that use antigenic variation to resist host immunity, through sequential modification of the parasite-derived variant erythrocyte surface antigen (VESA) expressed on the infected red blood cell surface. We identified the genomic processes driving antigenic diversity in genes encoding VESA (ves1) through comparative analysis within and between three Babesia species, (B. bigemina, B. divergens and B. bovis). Ves1 structure diverges rapidly after speciation, notably through the evolution of shortened forms (ves2) from 5? ends of canonical ves1 genes. Phylogenetic analyses show that ves1 genes are transposed between loci routinely, whereas ves2 genes are not. Similarly, analysis of sequence mosaicism shows that recombination drives variation in ves1 sequences, but less so for ves2, indicating the adoption of different mechanisms for variation of the two families. Proteomic analysis of the B. bigemina PR isolate shows that two dominant VESA1 proteins are expressed in the population, whereas numerous VESA2 proteins are co-expressed, consistent with differential transcriptional regulation of each family. Hence, VESA2 proteins are abundant and previously unrecognized elements of Babesia biology, with evolutionary dynamics consistently different to those of VESA1, suggesting that their functions are distinct. 2014 The Author(s) 2014.

The evolutionary dynamics of variant antigen genes in Babesia reveal a history of genomic innovation underlying host–parasite interaction

Science.gov (United States)

Jackson, Andrew P.; Otto, Thomas D.; Darby, Alistair; Ramaprasad, Abhinay; Xia, Dong; Echaide, Ignacio Eduardo; Farber, Marisa; Gahlot, Sunayna; Gamble, John; Gupta, Dinesh; Gupta, Yask; Jackson, Louise; Malandrin, Laurence; Malas, Tareq B.; Moussa, Ehab; Nair, Mridul; Reid, Adam J.; Sanders, Mandy; Sharma, Jyotsna; Tracey, Alan; Quail, Mike A.; Weir, William; Wastling, Jonathan M.; Hall, Neil; Willadsen, Peter; Lingelbach, Klaus; Shiels, Brian; Tait, Andy; Berriman, Matt; Allred, David R.; Pain, Arnab

2014-01-01

Babesia spp. are tick-borne, intraerythrocytic hemoparasites that use antigenic variation to resist host immunity, through sequential modification of the parasite-derived variant erythrocyte surface antigen (VESA) expressed on the infected red blood cell surface. We identified the genomic processes driving antigenic diversity in genes encoding VESA (ves1) through comparative analysis within and between three Babesia species, (B. bigemina, B. divergens and B. bovis). Ves1 structure diverges rapidly after speciation, notably through the evolution of shortened forms (ves2) from 5′ ends of canonical ves1 genes. Phylogenetic analyses show that ves1 genes are transposed between loci routinely, whereas ves2 genes are not. Similarly, analysis of sequence mosaicism shows that recombination drives variation in ves1 sequences, but less so for ves2, indicating the adoption of different mechanisms for variation of the two families. Proteomic analysis of the B. bigemina PR isolate shows that two dominant VESA1 proteins are expressed in the population, whereas numerous VESA2 proteins are co-expressed, consistent with differential transcriptional regulation of each family. Hence, VESA2 proteins are abundant and previously unrecognized elements of Babesia biology, with evolutionary dynamics consistently different to those of VESA1, suggesting that their functions are distinct. PMID:24799432

Tolerance induction to cytoplasmic beta-galactosidase by hepatic AAV gene transfer: implications for antigen presentation and immunotoxicity.

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Ashley T Martino

2009-08-01

Full Text Available Hepatic gene transfer, in particular using adeno-associated viral (AAV vectors, has been shown to induce immune tolerance to several protein antigens. This approach has been exploited in animal models of inherited protein deficiency for systemic delivery of therapeutic proteins. Adequate levels of transgene expression in hepatocytes induce a suppressive T cell response, thereby promoting immune tolerance. This study addresses the question of whether AAV gene transfer can induce tolerance to a cytoplasmic protein.AAV-2 vector-mediated hepatic gene transfer for expression of cytoplasmic beta-galactosidase (beta-gal was performed in immune competent mice, followed by a secondary beta-gal gene transfer with E1/E3-deleted adenoviral Ad-LacZ vector to provoke a severe immunotoxic response. Transgene expression from the AAV-2 vector in approximately 2% of hepatocytes almost completely protected from inflammatory T cell responses against beta-gal, eliminated antibody formation, and significantly reduced adenovirus-induced hepatotoxicity. Consequently, approximately 10% of hepatocytes continued to express beta-gal 45 days after secondary Ad-LacZ gene transfer, a time point when control mice had lost all Ad-LacZ derived expression. Suppression of inflammatory T cell infiltration in the liver and liver damage was linked to specific transgene expression and was not seen for secondary gene transfer with Ad-GFP. A combination of adoptive transfer studies and flow cytometric analyses demonstrated induction of Treg that actively suppressed CD8(+ T cell responses to beta-gal and that was amplified in liver and spleen upon secondary Ad-LacZ gene transfer.These data demonstrate that tolerance induction by hepatic AAV gene transfer does not require systemic delivery of the transgene product and that expression of a cytoplasmic neo-antigen in few hepatocytes can induce Treg and provide long-term suppression of inflammatory responses and immunotoxicity.

Cloning, sequence analysis, and expression of the large subunit of the human lymphocyte activation antigen 4F2

International Nuclear Information System (INIS)

Lumadue, J.A.; Glick, A.B.; Ruddle, F.H.

1987-01-01

Among the earliest expressed antigens on the surface of activated human lymphocytes is the surface antigen 4F2. The authors have used DNA-mediated gene transfer and fluorescence-activated cell sorting to obtain cell lines that contain the gene encoding the large subunit of the human 4F2 antigen in a mouse L-cell background. Human DNAs cloned from these cell lines were subsequently used as hybridization probes to isolate a full-length cDNA clone expressing 4F2. Sequence analysis of the coding region has revealed an amino acid sequence of 529 residues. Hydrophobicity plotting has predicted a probable structure for the protein that includes an external carboxyl terminus, an internal leader sequence, a single hydrophobic transmembrane domain, and two possible membrane-associated domains. The 4F2 cDNA detects a single 1.8-kilobase mRNA in T-cell and B-cell lines. RNA gel blot analysis of RNA derived from quiescent and serum-stimulated Swiss 3T3 fibroblasts reveals a cell-cycle modulation of 4F2 gene expression: the mRNA is present in quiescent fibroblasts but increases 8-fold 24-36 hr after stimulation, at the time of maximal DNA synthesis

Cloning, sequence analysis, and expression of the large subunit of the human lymphocyte activation antigen 4F2

Energy Technology Data Exchange (ETDEWEB)

Lumadue, J.A.; Glick, A.B.; Ruddle, F.H.

1987-12-01

Among the earliest expressed antigens on the surface of activated human lymphocytes is the surface antigen 4F2. The authors have used DNA-mediated gene transfer and fluorescence-activated cell sorting to obtain cell lines that contain the gene encoding the large subunit of the human 4F2 antigen in a mouse L-cell background. Human DNAs cloned from these cell lines were subsequently used as hybridization probes to isolate a full-length cDNA clone expressing 4F2. Sequence analysis of the coding region has revealed an amino acid sequence of 529 residues. Hydrophobicity plotting has predicted a probable structure for the protein that includes an external carboxyl terminus, an internal leader sequence, a single hydrophobic transmembrane domain, and two possible membrane-associated domains. The 4F2 cDNA detects a single 1.8-kilobase mRNA in T-cell and B-cell lines. RNA gel blot analysis of RNA derived from quiescent and serum-stimulated Swiss 3T3 fibroblasts reveals a cell-cycle modulation of 4F2 gene expression: the mRNA is present in quiescent fibroblasts but increases 8-fold 24-36 hr after stimulation, at the time of maximal DNA synthesis.

Vaccine-induced modulation of gene expression in turbot peritoneal cells. A microarray approach.

Science.gov (United States)

Fontenla, Francisco; Blanco-Abad, Verónica; Pardo, Belén G; Folgueira, Iria; Noia, Manuel; Gómez-Tato, Antonio; Martínez, Paulino; Leiro, José M; Lamas, Jesús

2016-07-01

We used a microarray approach to examine changes in gene expression in turbot peritoneal cells after injection of the fish with vaccines containing the ciliate parasite Philasterides dicentrarchi as antigen and one of the following adjuvants: chitosan-PVMMA microspheres, Freund́s complete adjuvant, aluminium hydroxide gel or Matrix-Q (Isconova, Sweden). We identified 374 genes that were differentially expressed in all groups of fish. Forty-two genes related to tight junctions and focal adhesions and/or actin cytoskeleton were differentially expressed in free peritoneal cells. The profound changes in gene expression related to cell adherence and cytoskeleton may be associated with cell migration and also with the formation of cell-vaccine masses and their attachment to the peritoneal wall. Thirty-five genes related to apoptosis were differentially expressed. Although most of the proteins coded by these genes have a proapoptotic effect, others are antiapoptotic, indicating that both types of signals occur in peritoneal leukocytes of vaccinated fish. Interestingly, many of the genes related to lymphocytes and lymphocyte activity were downregulated in the groups injected with vaccine. We also observed decreased expression of genes related to antigen presentation, suggesting that macrophages (which were abundant in the peritoneal cavity after vaccination) did not express these during the early inflammatory response in the peritoneal cavity. Finally, several genes that participate in the inflammatory response were differentially expressed, and most participated in resolution of inflammation, indicating that an M2 macrophage response is generated in the peritoneal cavity of fish one day post vaccination. Copyright © 2016 Elsevier Ltd. All rights reserved.

Human leukocyte antigen-G polymorphism in relation to expression, function, and disease

DEFF Research Database (Denmark)

Larsen, Margit Hørup; Hviid, Thomas

2009-01-01

Human leukocyte antigen-G (HLA-G) is a nonclassical class Ib molecule belonging to the major histocompatibility complex. HLA-G appears to play a role in the suppression of immune responses and contribute to long-term immune escape or tolerance. The focus of this review is polymorphism in the HLA......-G gene and protein and its possible importance in expression, function, and disease associations....

Mass Spectrometry Reveals Changes in MHC I Antigen Presentation After Lentivector Expression of a Gene Regulation System

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Roland Vogel

2013-01-01

Full Text Available The rapamycin-inducible gene regulation system was designed to minimize immune reactions in man and may thus be suited for gene therapy. We assessed whether this system indeed induces no immune responses. The protein components of the regulation system were produced in the human cell lines HEK 293T, D407, and HER 911 following lentiviral transfer of the corresponding genes. Stable cell lines were established, and the peptides presented by major histocompatibility complex class I (MHC I molecules on transduced and wild-type (wt cells were compared by differential mass spectrometry. In all cell lines examined, expression of the transgenes resulted in prominent changes in the repertoire of MHC I-presented self-peptides. No MHC I ligands originating from the transgenic proteins were detected. In vitro analysis of immunogenicity revealed that transduced D407 cells displayed slightly higher capacity than wt controls to promote proliferation of cytotoxic T cells. These results indicate that therapeutic manipulations within the genome of target cells may affect pathways involved in the processing of peptide antigens and their presentation by MHC I. This makes the genomic modifications visible to the immune system which may recognize these events and respond. Ultimately, the findings call attention to a possible immune risk.

Temporal expression and localization patterns of variant surface antigens in clinical Plasmodium falciparum isolates during erythrocyte schizogony.

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Anna Bachmann

Full Text Available Avoidance of antibody-mediated immune recognition allows parasites to establish chronic infections and enhances opportunities for transmission. The human malaria parasite Plasmodium falciparum possesses a number of multi-copy gene families, including var, rif, stevor and pfmc-2tm, which encode variant antigens believed to be expressed on the surfaces of infected erythrocytes. However, most studies of these antigens are based on in vitro analyses of culture-adapted isolates, most commonly the laboratory strain 3D7, and thus may not be representative of the unique challenges encountered by P. falciparum in the human host. To investigate the expression of the var, rif-A, rif-B, stevor and pfmc-2tm family genes under conditions that mimic more closely the natural course of infection, ex vivo clinical P. falciparum isolates were analyzed using a novel quantitative real-time PCR approach. Expression patterns in the clinical isolates at various time points during the first intraerythrocytic developmental cycle in vitro were compared to those of strain 3D7. In the clinical isolates, in contrast to strain 3D7, there was a peak of expression of the multi-copy gene families rif-A, stevor and pfmc-2tm at the young ring stage, in addition to the already known expression peak in trophozoites. Furthermore, most of the variant surface antigen families were overexpressed in the clinical isolates relative to 3D7, with the exception of the pfmc-2tm family, expression of which was higher in 3D7 parasites. Immunofluorescence analyses performed in parallel revealed two stage-dependent localization patterns of RIFIN, STEVOR and PfMC-2TM. Proteins were exported into the infected erythrocyte at the young trophozoite stage, whereas they remained inside the parasite membrane during schizont stage and were subsequently observed in different compartments in the merozoite. These results reveal a complex pattern of expression of P. falciparum multi-copy gene families during

Elimination of contaminating cap genes in AAV vector virions reduces immune responses and improves transgene expression in a canine gene therapy model.

Science.gov (United States)

Wang, Z; Halbert, C L; Lee, D; Butts, T; Tapscott, S J; Storb, R; Miller, A D

2014-04-01

Animal and human gene therapy studies utilizing AAV vectors have shown that immune responses to AAV capsid proteins can severely limit transgene expression. The main source of capsid antigen is that associated with the AAV vectors, which can be reduced by stringent vector purification. A second source of AAV capsid proteins is that expressed from cap genes aberrantly packaged into AAV virions during vector production. This antigen source can be eliminated by the use of a cap gene that is too large to be incorporated into an AAV capsid, such as a cap gene containing a large intron (captron gene). Here, we investigated the effects of elimination of cap gene transfer and of vector purification by CsCl gradient centrifugation on AAV vector immunogenicity and expression following intramuscular injection in dogs. We found that both approaches reduced vector immunogenicity and that combining the two produced the lowest immune responses and highest transgene expression. This combined approach enabled the use of a relatively mild immunosuppressive regimen to promote robust micro-dystrophin gene expression in Duchenne muscular dystrophy-affected dogs. Our study shows the importance of minimizing AAV cap gene impurities and indicates that this improvement in AAV vector production may benefit human applications.

New Genome-Wide Algorithm Identifies Novel In-Vivo Expressed Mycobacterium Tuberculosis Antigens Inducing Human T-Cell Responses with Classical and Unconventional Cytokine Profiles

DEFF Research Database (Denmark)

Coppola, Mariateresa; van Meijgaarden, Krista E.; Franken, Kees L. M. C.

2016-01-01

-wide transcriptomics of Mtb infected lungs we developed data sets and methods to identify IVE-TB (in-vivo expressed Mtb) antigens expressed in the lung. Quantitative expression analysis of 2,068 Mtb genes from the predicted first operons identified the most upregulated IVE-TB genes during in-vivo pulmonary infection...

Suicide Gene Therapy to Increase the Safety of Chimeric Antigen Receptor-Redirected T Lymphocytes

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Monica Casucci, Attilio Bondanza

2011-01-01

Full Text Available Chimeric antigen receptors (CARs are generated by fusing the antigen-binding motif of a monoclonal antibody (mAb with the signal transduction machinery of the T-cell receptor (TCR. The genetic modification of T lymphocytes with chimeric receptors specific for tumor-associated antigens (TAAs allows for the redirection towards tumor cells. Clinical experience with CAR-redirected T cells suggests that antitumor efficacy associates with some degree of toxicity, especially when TAA expression is shared with healthy tissues. This situation closely resembles the case of allogeneic hematopoietic stem cell transplantation (HSCT, wherein allorecognition causes both the graft-versus-leukemia (GVL effect and graft-versus-host disease (GVHD. Suicide gene therapy, i.e. the genetic induction of a conditional suicide phenotype into donor T cells, enables dissociating the GVL effect from GVHD. Applying suicide gene modification to CAR-redirected T cells may therefore greatly increase their safety profile and facilitate their clinical development.

Ebola virus infection induces irregular dendritic cell gene expression.

Science.gov (United States)

Melanson, Vanessa R; Kalina, Warren V; Williams, Priscilla

2015-02-01

Filoviruses subvert the human immune system in part by infecting and replicating in dendritic cells (DCs). Using gene arrays, a phenotypic profile of filovirus infection in human monocyte-derived DCs was assessed. Monocytes from human donors were cultured in GM-CSF and IL-4 and were infected with Ebola virus Kikwit variant for up to 48 h. Extracted DC RNA was analyzed on SuperArray's Dendritic and Antigen Presenting Cell Oligo GEArray and compared to uninfected controls. Infected DCs exhibited increased expression of cytokine, chemokine, antiviral, and anti-apoptotic genes not seen in uninfected controls. Significant increases of intracellular antiviral and MHC I and II genes were also noted in EBOV-infected DCs. However, infected DCs failed to show any significant difference in co-stimulatory T-cell gene expression from uninfected DCs. Moreover, several chemokine genes were activated, but there was sparse expression of chemokine receptors that enabled activated DCs to home to lymph nodes. Overall, statistically significant expression of several intracellular antiviral genes was noted, which may limit viral load but fails to stop replication. EBOV gene expression profiling is of vital importance in understanding pathogenesis and devising novel therapeutic treatments such as small-molecule inhibitors.

Heterologous expression of antigenic peptides in Bacillus subtilis biofilms.

Science.gov (United States)

Vogt, Cédric M; Schraner, Elisabeth M; Aguilar, Claudio; Eichwald, Catherine

2016-08-11

Numerous strategies have been developed for the display of heterologous proteins in the surface of live bacterial carriers, which can be used as vaccines, immune-modulators, cancer therapy or bioremediation. Bacterial biofilms have emerged as an interesting approach for the expression of proteins of interest. Bacillus subtilis is a well-described, endospore-forming organism that is able to form biofilms and also used as a probiotic, thus making it a suitable candidate for the display of heterologous proteins within the biofilm. Here, we describe the use of TasA, an important structural component of the biofilms formed by B. subtilis, as a genetic tool for the display of heterologous proteins. We first engineered the fusion protein TasA-mCherry and showed that was widely deployed within the B. subtilis biofilms. A significant enhancement of the expression of TasA-mCherry within the biofilm was obtained when depleting both tasA and sinR genes. We subsequently engineered fusion proteins of TasA to antigenic peptides of the E. granulosus parasite, paramyosin and tropomyosin. Our results show that the antigens were well expressed within the biofilm as denoted by macrostructure complementation and by the detection of the fusion protein in both immunoblot and immunohistochemistry. In addition, we show that the recombinant endospores of B. subtilis preserve their biophysical and morphological properties. In this work we provide strong evidence pointing that TasA is a suitable candidate for the display of heterologous peptides, such as antigens, cytokines, enzymes or antibodies, in the B. subtilis biofilms. Finally, our data portray that the recombinant endospores preserve their morphological and biophysical properties and could be an excellent tool to facilitate the transport and the administration.

The evolutionary dynamics of variant antigen genes in Babesia reveal a history of genomic innovation underlying host-parasite interaction.

Science.gov (United States)

Jackson, Andrew P; Otto, Thomas D; Darby, Alistair; Ramaprasad, Abhinay; Xia, Dong; Echaide, Ignacio Eduardo; Farber, Marisa; Gahlot, Sunayna; Gamble, John; Gupta, Dinesh; Gupta, Yask; Jackson, Louise; Malandrin, Laurence; Malas, Tareq B; Moussa, Ehab; Nair, Mridul; Reid, Adam J; Sanders, Mandy; Sharma, Jyotsna; Tracey, Alan; Quail, Mike A; Weir, William; Wastling, Jonathan M; Hall, Neil; Willadsen, Peter; Lingelbach, Klaus; Shiels, Brian; Tait, Andy; Berriman, Matt; Allred, David R; Pain, Arnab

2014-06-01

Babesia spp. are tick-borne, intraerythrocytic hemoparasites that use antigenic variation to resist host immunity, through sequential modification of the parasite-derived variant erythrocyte surface antigen (VESA) expressed on the infected red blood cell surface. We identified the genomic processes driving antigenic diversity in genes encoding VESA (ves1) through comparative analysis within and between three Babesia species, (B. bigemina, B. divergens and B. bovis). Ves1 structure diverges rapidly after speciation, notably through the evolution of shortened forms (ves2) from 5' ends of canonical ves1 genes. Phylogenetic analyses show that ves1 genes are transposed between loci routinely, whereas ves2 genes are not. Similarly, analysis of sequence mosaicism shows that recombination drives variation in ves1 sequences, but less so for ves2, indicating the adoption of different mechanisms for variation of the two families. Proteomic analysis of the B. bigemina PR isolate shows that two dominant VESA1 proteins are expressed in the population, whereas numerous VESA2 proteins are co-expressed, consistent with differential transcriptional regulation of each family. Hence, VESA2 proteins are abundant and previously unrecognized elements of Babesia biology, with evolutionary dynamics consistently different to those of VESA1, suggesting that their functions are distinct. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

Enhanced expression of codon optimized Mycobacterium avium subsp. paratuberculosis antigens in Lactobacillus salivarius

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Christopher D Johnston

2014-09-01

Full Text Available It is well documented that open reading frames containing high GC content show poor expression in A+T rich hosts. Specifically, G+C-rich codon usage is a limiting factor in heterologous expression of Mycobacterium avium subsp. paratuberculosis (MAP proteins using Lactobacillus salivarius. However, re-engineering opening reading frames through synonymous substitutions can offset codon bias and greatly enhance MAP protein production in this host. In this report, we demonstrate that codon-usage manipulation of two MAP genes (MAP2121c and MAP3733c can enhance the heterologous expression of two antigens (MMP and MptD respectively, analogous to the form to which they are produced natively by MAP bacilli. When heterologously over-expressed, antigenic determinants were preserved in synthetic MMP proteins as shown by monoclonal antibody mediated ELISA. Moreover, MMP is a membrane protein in MAP, which is also targeted to the cellular surface of recombinant L. salivarius at levels comparable to MAP. Additionally, codon optimised MptD displayed the tendency to associate with the cytoplasmic membrane boundary under confocal microscopy and the intracellularly accumulated protein selectively adhered with the MptD-specific bacteriophage fMptD. This work demonstrates there is potential for L. salivarius as a viable antigen delivery vehicle for MAP, which may provide an effective mucosal vaccine against Johne’s disease.

Gene expression in periodontal tissues following treatment

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Eisenacher Martin

2008-07-01

Full Text Available Abstract Background In periodontitis, treatment aimed at controlling the periodontal biofilm infection results in a resolution of the clinical and histological signs of inflammation. Although the cell types found in periodontal tissues following treatment have been well described, information on gene expression is limited to few candidate genes. Therefore, the aim of the study was to determine the expression profiles of immune and inflammatory genes in periodontal tissues from sites with severe chronic periodontitis following periodontal therapy in order to identify genes involved in tissue homeostasis. Gingival biopsies from 12 patients with severe chronic periodontitis were taken six to eight weeks following non-surgical periodontal therapy, and from 11 healthy controls. As internal standard, RNA of an immortalized human keratinocyte line (HaCaT was used. Total RNA was subjected to gene expression profiling using a commercially available microarray system focusing on inflammation-related genes. Post-hoc confirmation of selected genes was done by Realtime-PCR. Results Out of the 136 genes analyzed, the 5% most strongly expressed genes compared to healthy controls were Interleukin-12A (IL-12A, Versican (CSPG-2, Matrixmetalloproteinase-1 (MMP-1, Down syndrome critical region protein-1 (DSCR-1, Macrophage inflammatory protein-2β (Cxcl-3, Inhibitor of apoptosis protein-1 (BIRC-1, Cluster of differentiation antigen 38 (CD38, Regulator of G-protein signalling-1 (RGS-1, and Finkel-Biskis-Jinkins murine osteosarcoma virus oncogene (C-FOS; the 5% least strongly expressed genes were Receptor-interacting Serine/Threonine Kinase-2 (RIP-2, Complement component 3 (C3, Prostaglandin-endoperoxide synthase-2 (COX-2, Interleukin-8 (IL-8, Endothelin-1 (EDN-1, Plasminogen activator inhibitor type-2 (PAI-2, Matrix-metalloproteinase-14 (MMP-14, and Interferon regulating factor-7 (IRF-7. Conclusion Gene expression profiles found in periodontal tissues following

Spontaneous loss and alteration of antigen receptor expression in mature CD4+ T cells

International Nuclear Information System (INIS)

Kyoizumi, Seishi; Akiyama, Mitoshi; Hirai, Yuko; Kusunoki; Yoichiro; Tanabe, Kazumi; Umeki, Shigeko; Nakamura, Nori; Yamakido, Michio; Hamamoto, Kazuko.

1990-04-01

The T-cell receptor CD3 (TCR/CD3) complex plays a central role in antigen recognition and activation of mature T cells, and therefore abnormalities in the expression of the complex should induce unresponsiveness of T cells to antigen stimulus. Using flow cytometry, we detected and enumerated variant cells with loss or alteration of surface TCR/CD3 expression among human mature CD4 + T cells. The presence of variant CD4 + T cells was demonstrated by isolating and cloning them from peripheral blood, and their abnormalities can be accounted for by alterations in TCR expression such as defects of protein expression and partial protein deletion. The variant frequency in peripheral blood increased with aging in normal donors and was highly elevated in patients with ataxia telangiectasia, an autosomal recessive inherited disease with defective DNA repair and variable T-cell immunodeficiency. These findings suggest that such alterations in TCR expression are induced by somatic mutagenesis of TCR genes and can be important factors related to age-dependent and genetic disease-associated T-cell dysfunction. (author)

Characterization and gene expression analysis of the cir multi-gene family of plasmodium chabaudi chabaudi (AS)

KAUST Repository

Lawton, Jennifer

2012-03-29

Background: The pir genes comprise the largest multi-gene family in Plasmodium, with members found in P. vivax, P. knowlesi and the rodent malaria species. Despite comprising up to 5% of the genome, little is known about the functions of the proteins encoded by pir genes. P. chabaudi causes chronic infection in mice, which may be due to antigenic variation. In this model, pir genes are called cirs and may be involved in this mechanism, allowing evasion of host immune responses. In order to fully understand the role(s) of CIR proteins during P. chabaudi infection, a detailed characterization of the cir gene family was required.Results: The cir repertoire was annotated and a detailed bioinformatic characterization of the encoded CIR proteins was performed. Two major sub-families were identified, which have been named A and B. Members of each sub-family displayed different amino acid motifs, and were thus predicted to have undergone functional divergence. In addition, the expression of the entire cir repertoire was analyzed via RNA sequencing and microarray. Up to 40% of the cir gene repertoire was expressed in the parasite population during infection, and dominant cir transcripts could be identified. In addition, some differences were observed in the pattern of expression between the cir subgroups at the peak of P. chabaudi infection. Finally, specific cir genes were expressed at different time points during asexual blood stages.Conclusions: In conclusion, the large number of cir genes and their expression throughout the intraerythrocytic cycle of development indicates that CIR proteins are likely to be important for parasite survival. In particular, the detection of dominant cir transcripts at the peak of P. chabaudi infection supports the idea that CIR proteins are expressed, and could perform important functions in the biology of this parasite. Further application of the methodologies described here may allow the elucidation of CIR sub-family A and B protein

Characterization and gene expression analysis of the cir multi-gene family of plasmodium chabaudi chabaudi (AS

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Lawton Jennifer

2012-03-01

Full Text Available Abstract Background The pir genes comprise the largest multi-gene family in Plasmodium, with members found in P. vivax, P. knowlesi and the rodent malaria species. Despite comprising up to 5% of the genome, little is known about the functions of the proteins encoded by pir genes. P. chabaudi causes chronic infection in mice, which may be due to antigenic variation. In this model, pir genes are called cirs and may be involved in this mechanism, allowing evasion of host immune responses. In order to fully understand the role(s of CIR proteins during P. chabaudi infection, a detailed characterization of the cir gene family was required. Results The cir repertoire was annotated and a detailed bioinformatic characterization of the encoded CIR proteins was performed. Two major sub-families were identified, which have been named A and B. Members of each sub-family displayed different amino acid motifs, and were thus predicted to have undergone functional divergence. In addition, the expression of the entire cir repertoire was analyzed via RNA sequencing and microarray. Up to 40% of the cir gene repertoire was expressed in the parasite population during infection, and dominant cir transcripts could be identified. In addition, some differences were observed in the pattern of expression between the cir subgroups at the peak of P. chabaudi infection. Finally, specific cir genes were expressed at different time points during asexual blood stages. Conclusions In conclusion, the large number of cir genes and their expression throughout the intraerythrocytic cycle of development indicates that CIR proteins are likely to be important for parasite survival. In particular, the detection of dominant cir transcripts at the peak of P. chabaudi infection supports the idea that CIR proteins are expressed, and could perform important functions in the biology of this parasite. Further application of the methodologies described here may allow the elucidation of CIR sub

Characterization and gene expression analysis of the cir multi-gene family of plasmodium chabaudi chabaudi (AS)

KAUST Repository

Lawton, Jennifer; Brugat, Thibaut; Yan, Yam Xue; Reid, Adam James; Bö hme, Ulrike; Otto, Thomas Dan; Pain, Arnab; Jackson, Andrew; Berriman, Matthew; Cunningham, Deirdre; Preiser, Peter; Langhorne, Jean

2012-01-01

Background: The pir genes comprise the largest multi-gene family in Plasmodium, with members found in P. vivax, P. knowlesi and the rodent malaria species. Despite comprising up to 5% of the genome, little is known about the functions of the proteins encoded by pir genes. P. chabaudi causes chronic infection in mice, which may be due to antigenic variation. In this model, pir genes are called cirs and may be involved in this mechanism, allowing evasion of host immune responses. In order to fully understand the role(s) of CIR proteins during P. chabaudi infection, a detailed characterization of the cir gene family was required.Results: The cir repertoire was annotated and a detailed bioinformatic characterization of the encoded CIR proteins was performed. Two major sub-families were identified, which have been named A and B. Members of each sub-family displayed different amino acid motifs, and were thus predicted to have undergone functional divergence. In addition, the expression of the entire cir repertoire was analyzed via RNA sequencing and microarray. Up to 40% of the cir gene repertoire was expressed in the parasite population during infection, and dominant cir transcripts could be identified. In addition, some differences were observed in the pattern of expression between the cir subgroups at the peak of P. chabaudi infection. Finally, specific cir genes were expressed at different time points during asexual blood stages.Conclusions: In conclusion, the large number of cir genes and their expression throughout the intraerythrocytic cycle of development indicates that CIR proteins are likely to be important for parasite survival. In particular, the detection of dominant cir transcripts at the peak of P. chabaudi infection supports the idea that CIR proteins are expressed, and could perform important functions in the biology of this parasite. Further application of the methodologies described here may allow the elucidation of CIR sub-family A and B protein

Natural Mutations in Streptococcus agalactiae Resulting in Abrogation of β Antigen Production.

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Vasilyeva, Anastasia; Santos Sanches, Ilda; Florindo, Carlos; Dmitriev, Alexander

2015-01-01

Streptococcus agalactiae genome encodes 21 two-component systems (TCS) and a variety of regulatory proteins in order to control gene expression. One of the TCS, BgrRS, comprising the BgrR DNA-binding regulatory protein and BgrS sensor histidine kinase, was discovered within a putative virulence island. BgrRS influences cell metabolism and positively control the expression of bac gene, coding for β antigen at transcriptional level. Inactivation of bgrR abrogated bac gene expression and increased virulence properties of S. agalactiae. In this study, a total of 140 strains were screened for the presence of bac gene, and the TCS bgrR and bgrS genes. A total of 53 strains carried the bac, bgrR and bgrS genes. Most of them (48 strains) expressed β antigen, while five strains did not express β antigen. Three strains, in which bac gene sequence was intact, while bgrR and/or bgrS genes had mutations, and expression of β antigen was absent, were complemented with a constructed plasmid pBgrRS(P) encoding functionally active bgrR and bgrS gene alleles. This procedure restored expression of β antigen indicating the crucial regulatory role of TCS BgrRS. The complemented strain A49V/BgrRS demonstrated attenuated virulence in intraperitoneal mice model of S. agalactiae infection compared to parental strain A49V. In conclusion we showed that disruption of β antigen expression is associated with: i) insertion of ISSa4 upstream the bac gene just after the ribosomal binding site; ii) point mutation G342A resulting a stop codon TGA within the bac gene and a truncated form of β antigen; iii) single deletion (G) in position 439 of the bgrR gene resulting in a frameshift and the loss of DNA-binding domain of the BgrR protein, and iv) single base substitutions in bgrR and bgrS genes causing single amino acid substitutions in BgrR (Arg187Lys) and BgrS (Arg252Gln). The fact that BgrRS negatively controls virulent properties of S. agalactiae gives a novel clue for understanding of S

PRAME Gene Expression in Acute Leukemia and Its Clinical Significance

International Nuclear Information System (INIS)

Ding, Kai; Wang, Xiao-ming; Fu, Rong; Ruan, Er-bao; Liu, Hui; Shao, Zong-hong

2012-01-01

To investigate the expression of the preferentially expressed antigen of melanoma (PRAME) gene in acute leukemia and its clinical significance. The level of expressed PRAME mRNA in bone marrow mononuclear cells from 34 patients with acute leukemia (AL) and in 12 bone marrow samples from healthy volunteers was measured via RT-PCR. Correlation analyses between PRAME gene expression and the clinical characteristics (gender, age, white blood count, immunophenotype of leukemia, percentage of blast cells, and karyotype) of the patients were performed. The PRAME gene was expressed in 38.2% of all 34 patients, in 40.7% of the patients with acute myelogenous leukemia (AML, n=27), and in 28.6% of the patients with acute lymphoblastic leukemia (ALL, n=7), but was not expressed in the healthy volunteers. The difference in the expression levels between AML and ALL patients was statistically significant. The rate of gene expression was 80% in M 3 , 33.3% in M 2 , and 28.6% in M 5 . Gene expression was also found to be correlated with CD15 and CD33 expression and abnormal karyotype, but not with age, gender, white blood count or percentage of blast cells. The PRAME gene is highly expressed in acute leukemia and could be a useful marker to monitor minimal residual disease. This gene is also a candidate target for the immunotherapy of acute leukemia

A mouse model for chronic lymphocytic leukemia based on expression of the SV40 large T antigen

DEFF Research Database (Denmark)

ter Brugge, Petra J; Ta, Van B T; de Bruijn, Marjolein J W

2009-01-01

The simian virus 40 (SV40) T antigen is a potent oncogene able to transform many cell types and has been implicated in leukemia and lymphoma. In this report, we have achieved sporadic SV40 T-antigen expression in mature B cells in mice, by insertion of a SV40 T antigen gene in opposite...... transcriptional orientation in the immunoglobulin (Ig) heavy (H) chain locus between the D and J(H) segments. SV40 T-antigen expression appeared to result from retention of the targeted germline allele and concomitant antisense transcription of SV40 large T in mature B cells, leading to chronic lymphocytic...... leukemia (CLL). Although B-cell development was unperturbed in young mice, aging mice showed accumulation of a monoclonal B-cell population in which the targeted IgH allele was in germline configuration and the wild-type IgH allele had a productive V(D)J recombination. These leukemic B cells were Ig...

Identification of immune protective genes of Eimeria maxima through cDNA expression library screening.

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Yang, XinChao; Li, MengHui; Liu, JianHua; Ji, YiHong; Li, XiangRui; Xu, LiXin; Yan, RuoFeng; Song, XiaoKai

2017-02-16

Eimeria maxima is one of the most prevalent Eimeria species causing avian coccidiosis, and results in huge economic loss to the global poultry industry. Current control strategies, such as anti-coccidial medication and live vaccines have been limited because of their drawbacks. The third generation anticoccidial vaccines including the recombinant vaccines as well as DNA vaccines have been suggested as a promising alternative strategy. To date, only a few protective antigens of E. maxima have been reported. Hence, there is an urgent need to identify novel protective antigens of E. maxima for the development of neotype anticoccidial vaccines. With the aim of identifying novel protective genes of E. maxima, a cDNA expression library of E. maxima sporozoites was constructed using Gateway technology. Subsequently, the cDNA expression library was divided into 15 sub-libraries for cDNA expression library immunization (cDELI) using parasite challenged model in chickens. Protective sub-libraries were selected for the next round of screening until individual protective clones were obtained, which were further sequenced and analyzed. Adopting the Gateway technology, a high-quality entry library was constructed, containing 9.2 × 10 6 clones with an average inserted fragments length of 1.63 kb. The expression library capacity was 2.32 × 10 7 colony-forming units (cfu) with an average inserted fragments length of 1.64 Kb. The expression library was screened using parasite challenged model in chickens. The screening yielded 6 immune protective genes including four novel protective genes of EmJS-1, EmRP, EmHP-1 and EmHP-2, and two known protective genes of EmSAG and EmCKRS. EmJS-1 is the selR domain-containing protein of E. maxima whose function is unknown. EmHP-1 and EmHP-2 are the hypothetical proteins of E. maxima. EmRP and EmSAG are rhomboid-like protein and surface antigen glycoproteins of E. maxima respectively, and involved in invasion of the parasite. Our

Affinity Maturation of an Anti-V Antigen IgG Expressed In Situ Via Adenovirus Gene Delivery Confers Enhanced Protection Against Yersinia pestis Challenge

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Van Blarcom, Thomas J.; Sofer-Podesta, Carolina; Ang, John; Boyer, Julie L.; Crystal, Ronald G.; Georgiou, George

2013-01-01

Genetic transfer of neutralizing antibodies has been shown to confer strong and persistent protection against bacterial and viral infectious agents. While it is well established that for many exogenous neutralizing antibodies increased antigen affinity correlates with protection, the effect of antigen affinity on antibodies produced in situ following adenoviral gene transfer has not been examined. The mouse IgG2b monoclonal antibody 2C12.4 recognizes the Yersinia pestis Type III secretion apparatus protein LcrV (V antigen) and confers protection in mice when administered as an IgG intraperitoneally or, following genetic immunization with engineered, replication-defective serotype 5 human adenovirus (Ad) 1. 2C12.4 was expressed as a scFv fragment in E. coli and was shown to display a KD=3.5 nM by surface plasmon resonance (SPR) analysis. The 2C12.4 scFv was subjected to random mutagenesis and variants with increased affinity were isolated by flow cytometry using the Anchored Periplasmic Expression (APEx) bacterial display system. After a single round of mutagenesis, variants displaying up to 35-fold lower KD values (H8, KD=100 pM) were isolated. The variable domains of the H8 scFv were used to replace those of the parental 2C12.4 IgG encoded in the Ad vector, AdαV giving rise to AdαV.H8. The two adenoviral vectors resulted in similar titers of anti-V antigen antibodies 3 days post-immunization with 109, 1010 or 1011 particle units. Following intranasal challenge with 363 LD50Y. pestis CO92, 54% of the mice immunized with 1010 pu of AdαV.H8 survived at the 14 day end point compared to only 15% survivors for the group immunized with AdαV expressing the lower affinity 2C12.4 (Pgenetic transfer may confer increased protection not only for Y. pestis challenge but possibly for other pathogens. PMID:20393511

Chloroplast-Derived Vaccine Antigens and Biopharmaceuticals: Expression, Folding, Assembly and Functionality

Science.gov (United States)

Chebolu, S.; Daniell, H.

2009-01-01

Chloroplast genetic engineering offers several advantages, including high levels of transgene expression, transgene containment via maternal inheritance, and multi-gene expression in a single transformation event. Oral delivery is facilitated by hyperexpression of vaccine antigens against cholera, tetanus, anthrax, plague, or canine parvovirus (4%–31% of total soluble protein, TSP) in transgenic chloroplasts (leaves) or non-green plastids (carrots, tomato) as well as the availability of antibiotic free selectable markers or the ability to excise selectable marker genes. Hyperexpression of several therapeutic proteins, including human serum albumin (11.1% TSP), somatotropin (7% TSP), interferon-alpha (19% TSP), interferon-gamma (6% TSP), and antimicrobial peptide (21.5% TSP), facilitates efficient and economic purification. Also, the presence of chaperones and enzymes in chloroplasts facilitates assembly of complex multisubunit proteins and correct folding of human blood proteins with proper disulfide bonds. Functionality of chloroplast-derived vaccine antigens and therapeutic proteins has been demonstrated by several assays, including the macrophage lysis assay, GM1-ganglioside binding assay, protection of HeLA cells or human lung carcinoma cells against encephalomyocarditis virus, systemic immune response, protection against pathogen challenge, and growth or inhibition of cell cultures. Purification of human proinsulin has been achieved using novel purification strategies (inverse temperature transition property) that do not require expensive column chromatography techniques. Thus, transgenic chloroplasts are ideal bioreactors for production of functional human and animal therapeutic proteins in an environmentally friendly manner. PMID:19401820

Defining the expression of marker genes in equine mesenchymal stromal cells

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Deborah J Guest

2008-11-01

Full Text Available Deborah J Guest1, Jennifer C Ousey1, Matthew RW Smith21Animal Health Trust, Lanwades Park, Kentford, Newmarket, Suffolk, CB8 7UU; 2Reynolds House Referrals, Greenwood Ellis and Partners, 166 High Street, Newmarket, Suffolk, CB8 9WS, UKAbstract: Mesenchymal stromal (MS cells have been derived from multiple sources in the horse including bone marrow, adipose tissue and umbilical cord blood. To date these cells have been investigated for their differentiation potential and are currently being used to treat damage to horse musculoskeletal tissues. However, no work has been done in horse MS cells to examine the expression profile of proteins and cell surface antigens that are expressed in human MS cells. The identification of such profiles in the horse will allow the comparison of putative MS cells isolated from different laboratories and different tissues. At present it is difficult to ascertain whether equivalent cells are being used in different reports. Here, we report on the expression of a range of markers used to define human MS cells. Using immunocytochemistry we show that horse MS cells homogenously express collagens, alkaline phosphatase activity, CD44, CD90 and CD29. In contrast, CD14, CD79α and the embryonic stem cell markers Oct-4, SSEA (stage specific embryonic antigen -1, -3, -4, TRA (tumor rejection antigen -1–60 and -1–81 are not expressed. The MS cells also express MHC class I antigens but do not express class II antigens, although they are inducible by treatment with interferon gamma (IFN-γ.Keywords: mesenchymal stem cells, equine, gene expression

Analysis of CD83 antigen expression in human breast fibroadenoma and adjacent tissue

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Marcus Nascimento Borges

Full Text Available CONTEXT AND OBJECTIVE: Dendritic cell maturation is considered essential for starting an immune response. The CD83 antigen is an important marker of dendritic cell maturation. The objectives here were to analyze CD83 antigen expression in human breast fibroadenoma and breast tissue adjacent to the lesion and to identify clinical factors that might influence this expression. DESIGN AND SETTING: This was a retrospective study at a public university hospital, in which 29 histopathological samples of breast fibroadenoma and adjacent breast tissue, from 28 women of reproductive age, were analyzed. METHODS: The immunohistochemistry method was used to analyze the cell expression of the antigen. The antigen expression in the cells was evaluated by means of random manual counting using an optical microscope. RESULTS: Positive expression of the CD83 antigen in the epithelial cells of the fibroadenoma (365.52; standard deviation ± 133.13 in relation to the adjacent breast tissue cells (189.59; standard deviation ± 140.75 was statistically larger (P < 0.001. Several clinical features were analyzed, but only parity was shown to influence CD83 antigen expression in the adjacent breast tissue, such that positive expression was more evident in nulliparous women (P = 0.042. CONCLUSIONS: The expression of the CD83 antigen in the fibroadenoma was positive and greater than in the adjacent breast tissue. Positive expression of the antigen in the adjacent breast tissue was influenced by parity, and was significantly more evident in nulliparous women.

Plasmodium falciparum variant STEVOR antigens are expressed in merozoites and possibly associated with erythrocyte invasion

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Petter Michaela

2008-07-01

Full Text Available Abstract Background Plasmodium falciparum STEVOR proteins, encoded by the multicopy stevor gene family have no known biological functions. Their expression and unique locations in different parasite life cycle stages evoke multiple functionalities. Their abundance and hypervariability support a role in antigenic variation. Methods Immunoblotting of total parasite proteins with an anti-STEVOR antibody was used to identify variant antigens of this gene family and to follow changes in STEVOR expression in parasite populations panned on CSA or CD36 receptors. Immunofluorescence assays and immunoelectron microscopy were performed to study the subcellular localization of STEVOR proteins in different parasite stages. The capacity of the antibody to inhibit merozoite invasion of erythrocytes was assessed to determine whether STEVOR variants were involved in the invasion process. Results Antigenic variation of STEVORs at the protein level was observed in blood stage parasites. STEVOR variants were found to be present on the merozoite surface and in rhoptries. An insight into a participation in erythrocyte invasion was gained through an immunofluorescence analysis of a sequence of thin slides representing progressive steps in erythrocyte invasion. An interesting feature of the staining pattern was what appeared to be the release of STEVORs around the invading merozoites. Because the anti-STEVOR antibody did not inhibit invasion, the role of STEVORs in this process remains unknown. Conclusion The localization of STEVOR proteins to the merozoite surface and the rhoptries together with its prevalence as a released component in the invading merozoite suggest a role of these antigens in adhesion and/or immune evasion in the erythrocyte invasion process. These observations would also justify STEVORs for undergoing antigenic variation. Even though a role in erythrocyte invasion remains speculative, an association of members of the STEVOR protein family with

Effect of radiation on the expression of tumor-associated antigens of human lung adenocarcinoma cells

International Nuclear Information System (INIS)

Hareyama, Masato

1988-01-01

We studied the effects of irradiation on the expression of a tumor-associated antigen (YH206 antigen) of cultured human lung adenocarcinoma A549 cells by using enzyme-linked immunosorbent assay (ELISA) and flow cytometry. YH206 antigen is preferentially expressed on adenocarcinoma cells. Irradiation of A549 cells remarkably increased the expression of YH206 antigen on the cell surface and the level of the antigen in the culture supernatant as well as in the cell lysate, whereas it significantly affected the expression of HLA (MHC-class I) antigen on the same cells. The expression of HLA antigen on the cell was also increased after treatment of the cells with interferon-γ. In an additional experiment, cells were stained simultaneously for surface antigens (fluorescein coupled antibodies) and for DNA content (propidium iodide), and then dual parameter measurements were performed by flow cytometry to analyse the relationship between antigen levels and the cell cycle. YH206 antigen and HLA antigen increased more in the S and G 2 /M phases of the cell cycle than in G 0 /G 1 . The expression of YH206 antigen was enhanced in the S and G 2 /M phases by irradiation, whereas the expression of HLA antigen was enhanced in each phase of the cell cycle with irradiation or IFN. These results suggest that irradiation plays a key role in the change of the expression of certain tumor-associated antigens. (author)

Transient expression of hemagglutinin antigen from low pathogenic avian influenza A (H7N7 in Nicotiana benthamiana.

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Selvaraju Kanagarajan

Full Text Available The influenza A virus is of global concern for the poultry industry, especially the H5 and H7 subtypes as they have the potential to become highly pathogenic for poultry. In this study, the hemagglutinin (HA of a low pathogenic avian influenza virus of the H7N7 subtype isolated from a Swedish mallard Anas platyrhynchos was sequenced, characterized and transiently expressed in Nicotiana benthamiana. Recently, plant expression systems have gained interest as an alternative for the production of vaccine antigens. To examine the possibility of expressing the HA protein in N. benthamiana, a cDNA fragment encoding the HA gene was synthesized de novo, modified with a Kozak sequence, a PR1a signal peptide, a C-terminal hexahistidine (6×His tag, and an endoplasmic retention signal (SEKDEL. The construct was cloned into a Cowpea mosaic virus (CPMV-based vector (pEAQ-HT and the resulting pEAQ-HT-HA plasmid, along with a vector (pJL3:p19 containing the viral gene-silencing suppressor p19 from Tomato bushy stunt virus, was agro-infiltrated into N. benthamiana. The highest gene expression of recombinant plant-produced, uncleaved HA (rHA0, as measured by quantitative real-time PCR was detected at 6 days post infiltration (dpi. Guided by the gene expression profile, rHA0 protein was extracted at 6 dpi and subsequently purified utilizing the 6×His tag and immobilized metal ion adsorption chromatography. The yield was 0.2 g purified protein per kg fresh weight of leaves. Further molecular characterizations showed that the purified rHA0 protein was N-glycosylated and its identity confirmed by liquid chromatography-tandem mass spectrometry. In addition, the purified rHA0 exhibited hemagglutination and hemagglutination inhibition activity indicating that the rHA0 shares structural and functional properties with native HA protein of H7 influenza virus. Our results indicate that rHA0 maintained its native antigenicity and specificity, providing a good source of

Establishment of a common acute lymphoblastic leukemia cell line (LC4-1) and effects of phorbol myristate acetate (PMA) on the surface antigen expression of the cell line.

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Yoshimura, T; Mayumi, M; Yorifuji, T; Kim, K M; Heike, T; Miyanomae, T; Shinomiya, K; Mikawa, H

1987-09-01

A common acute lymphoblastic leukemia (ALL) cell line, designated LC4-1, was established from peripheral blood mononuclear cells of a patient with acute non-T-cell ALL. LC4-1 cells were characteristically positive for Ia, B4, and common ALL antigens (CALLA), but negative for B2, Tac, T3, T4, T8, T11, and M1 antigens and E-rosette formation. Approximately 30% of LC4-1 cells expressed detectable amounts of B1 antigens. LC4-1 cells expressed neither Epstein-Barr-virus-associated nuclear antigen (EBNA), cytoplasmic immunoglobulins (cIg) nor surface immunoglobulins (sIg). Gene rearrangements had already occurred in LC4-1 in the D-J region of immunoglobulin heavy chain genes, but not in T-cell receptor (beta-chain) genes, suggesting that LC4-1 is a progenitor cell line of B-cell lineage earlier than pre-B-cells. The expression of cell surface antigens of LC4-1 was changed by treatment with 4-phorbol 12-myristate 13-acetate (PMA) (0.1 ng/ml) for 2 days. Before treatment with PMA, about 98% of LC4-1 cells were positive for B4, CALLA, and Ia. However, following treatment they lost CALLA expression without any change in expression of Ia and B4. There was no change in B1-positive population. The change in surface antigens on LC4-1 cells seems to be due to differentiation induced in the cells by PMA. These results support the hypothesis that CALLA is a differentiation antigen and suggest one possible differentiation pathway for pre-B-cells.

Novel Antitumor Strategy Utilizing a Plasmid Expressing a Mycobacterium tuberculosis Antigen as a “Danger Signal” to Block Immune Escape of Tumor Cells

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Yoshiyuki Koyama

2015-07-01

Full Text Available Immune escape of tumor cells is one of the main obstacles hindering the effectiveness of cancer immunotherapy. We developed a novel strategy to block immune escape by transfecting tumor cells in vivo with genes of pathogenic antigens from Mycobacterium tuberculosis (TB. This induces presentation of the TB antigen on tumor cell surfaces, which can be recognized by antigen presenting cells (APCs as a “danger signal” to stimulate antitumor immune response. This strategy is also expected to amplify the immune response against tumor-associated antigens, and block immune escape of the tumor. DNA/PEI/chondroitin sulfate ternary complex is a highly effective non-viral gene vector system for in vivo transfection. A therapeutic complex was prepared using a plasmid encoding the TB antigen, early secretory antigenic target-6 (ESAT-6. This was injected intratumorally into syngeneic tumor-bearing mice, and induced significant tumor growth suppression comparable to or higher than similar complexes expressing cytokines such as interleukin-2 (IL-2 and interleukin-12 (IL-12. Co-transfection of the cytokine-genes and the ESAT-6-gene enhanced the antitumor efficacy of either treatment alone. In addition, complete tumor regression was achieved with the combination of ESAT-6 and IL-2 genes.

[Prokaryotic expression and histological localization of the Taenia solium CDC37 gene].

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Huang, Jiang; Li, Bo; Dai, Jia-Lin; Zhang, Ai-Hua

2013-02-01

To express Taenia solium gene encoding cell division cycle 37 protein (TsCDC37) and investigate its antigenicity and localization in adults of Taenia solium. The complete coding sequence of TsCDC37 was amplified by PCR based on the recombinant plasmid clone from the cDNA library of adult Taenia solium. The PCR product was cloned into a prokaryotic expression vector pET-28a (+). The recombinant expression plasmid was identified by PCR, double endonuclease digestion and sequencing. The recombinant plasmid was transformed into E. coli BL21/DE3 and followed by expression of the protein induced by IPTG. The mice were immunized subcutaneously with purified recombinant TsCDC37 formulated in Freund's adjuvant. The antigenicity of the recombinant protein was examined by Western blotting. The localization of TsCDC37 in adult worms was demonstrated by immunofluorescent technique. The recombinant expression vector was constructed successfully. The recombinant protein was about M(r) 52 000, it was then purified and specifically recognized by immuno sera of SD rats and sera from patients infected with Taenia solium, Taenia saginata or Taenia asiatica. The immunofluorescence assay revealed that TsCDC37 located at the tegument of T. solium adult and the eggs. TsCDC37 gene has been expressed with immunoreactivity. The recombinant protein is mainly expressed in tegument and egg, and is a common antigen of the three human taenia cestodes.

Expression of Hepatitis C Virus Core and E2 antigenic recombinant proteins and their use for development of diagnostic assays.

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Ali, Amjad; Nisar, Muhammad; Idrees, Muhammad; Rafique, Shazia; Iqbal, Muhammad

2015-05-01

Early diagnosis of HCV infection is based on detection of antibodies against HCV proteins using recombinant viral antigens. The present study was designed to select, clone and express the antigenic regions of Core and E2 genes from local HCV-3a genotype and to utilize the antigenic recombinant proteins (Core & E2) to develop highly sensitive, specific and economical diagnostic assays for detection of HCV infection. The antigenic sites were determined within Core and E2 genes and were then cloned in pET-28a expression vector. The right orientation of the desired inserted fragments of Core and E2 were confirmed via sequencing prior to expression and were then transformed in BL21 (DE3) pLysS strains of E. coli and induced with 0.5mM Isopropyl-b-D-thiogalactopyranoside (IPTG) for the production of antigenic recombinant proteins. The produced truncated antigens were then purified by Nickel affinity chromatography and were confirmed by western blotting, immunoblotting and enzyme-linked immunosorbent assay (ELISA). The expressed Core and E2 recombinant antigens were used to develop immunoblotting assay for the detection of anti-HCV antibodies in sera. With immunoblotting, a total of 93-HCV infected sera and 35-HCV negative individuals were tested for the presence of anti-HCV antibodies to the Core and E2 antigens. Recombinant antigen showed 100% reactivity against HCV infected sera, with no cross reactivity against HCV-negative sera. The immunoblot assay mixture of recombinant antigens (Core+E2) showed a strong reaction intensity in the test area (TA) as compared to the individual truncated Core and E2 recombinant antigens. In the in-house ELISA assay, mixed Core and E2 recombinant antigens showed 100% reactivity against a standardized panel of 150-HCV-positive sera and non reactivity against a standardized panel of 150 HCV-negative sera while also being non reactive to sera positive for other viral infections. The antigenic recombinant antigens also were tested for the

Equivalent Gene Expression Profiles between Glatopa™ and Copaxone®.

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Josephine S D'Alessandro

Full Text Available Glatopa™ is a generic glatiramer acetate recently approved for the treatment of patients with relapsing forms of multiple sclerosis. Gene expression profiling was performed as a means to evaluate equivalence of Glatopa and Copaxone®. Microarray analysis containing 39,429 unique probes across the entire genome was performed in murine glatiramer acetate--responsive Th2-polarized T cells, a test system highly relevant to the biology of glatiramer acetate. A closely related but nonequivalent glatiramoid molecule was used as a control to establish assay sensitivity. Multiple probe-level (Student's t-test and sample-level (principal component analysis, multidimensional scaling, and hierarchical clustering statistical analyses were utilized to look for differences in gene expression induced by the test articles. The analyses were conducted across all genes measured, as well as across a subset of genes that were shown to be modulated by Copaxone. The following observations were made across multiple statistical analyses: the expression of numerous genes was significantly changed by treatment with Copaxone when compared against media-only control; gene expression profiles induced by Copaxone and Glatopa were not significantly different; and gene expression profiles induced by Copaxone and the nonequivalent glatiramoid were significantly different, underscoring the sensitivity of the test system and the multiple analysis methods. Comparative analysis was also performed on sets of transcripts relevant to T-cell biology and antigen presentation, among others that are known to be modulated by glatiramer acetate. No statistically significant differences were observed between Copaxone and Glatopa in the expression levels (magnitude and direction of these glatiramer acetate-regulated genes. In conclusion, multiple methods consistently supported equivalent gene expression profiles between Copaxone and Glatopa.

Mosquito Passage Dramatically Changes var Gene Expression in Controlled Human Plasmodium falciparum Infections.

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Bachmann, Anna; Petter, Michaela; Krumkamp, Ralf; Esen, Meral; Held, Jana; Scholz, Judith A M; Li, Tao; Sim, B Kim Lee; Hoffman, Stephen L; Kremsner, Peter G; Mordmüller, Benjamin; Duffy, Michael F; Tannich, Egbert

2016-04-01

Virulence of the most deadly malaria parasite Plasmodium falciparum is linked to the variant surface antigen PfEMP1, which is encoded by about 60 var genes per parasite genome. Although the expression of particular variants has been associated with different clinical outcomes, little is known about var gene expression at the onset of infection. By analyzing controlled human malaria infections via quantitative real-time PCR, we show that parasite populations from 18 volunteers expressed virtually identical transcript patterns that were dominated by the subtelomeric var gene group B and, to a lesser extent, group A. Furthermore, major changes in composition and frequency of var gene transcripts were detected between the parental parasite culture that was used to infect mosquitoes and Plasmodia recovered from infected volunteers, suggesting that P. falciparum resets its var gene expression during mosquito passage and starts with the broad expression of a specific subset of var genes when entering the human blood phase.

ABO blood group antigens in oral mucosa. What is new?

DEFF Research Database (Denmark)

Dabelsteen, Erik

2002-01-01

which represent secondary gene products. They are synthesized in a stepwise fashion from a precursor by the action of different glycosyltransferases. In non-keratinized oral mucosa, a sequential elongation of the carbohydrates is associated with differentiation of epithelial cells, resulting...... in expression of precursors on basal cells and A/B antigens on spinous cells. Reduction or complete deletion of A/B antigen expression in oral carcinomas has been reported, a phenotypic change that is correlated with invasive and metastatic potential of the tumours and with the mortality rates of the patients....... Disappearance of the antigens is ascribed to the absence of A or B transferase gene expression. Several studies have shown that loss of A and B antigen expression is associated with increased cell motility, invasion in matrigel, and tumourigenecity in syngenic animals. In vivo studies of human oral wound...

Analysis of CD83 antigen expression in human breast fibroadenoma and adjacent tissue.

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Borges, Marcus Nascimento; Facina, Gil; Silva, Ismael Dale Cotrin Guerreiro; Waitzberg, Angela Flávia Logullo; Nazario, Afonso Celso Pinto

2011-12-01

Dendritic cell maturation is considered essential for starting an immune response. The CD83 antigen is an important marker of dendritic cell maturation. The objectives here were to analyze CD83 antigen expression in human breast fibroadenoma and breast tissue adjacent to the lesion and to identify clinical factors that might influence this expression. This was a retrospective study at a public university hospital, in which 29 histopathological samples of breast fibroadenoma and adjacent breast tissue, from 28 women of reproductive age, were analyzed. The immunohistochemistry method was used to analyze the cell expression of the antigen. The antigen expression in the cells was evaluated by means of random manual counting using an optical microscope. Positive expression of the CD83 antigen in the epithelial cells of the fibroadenoma (365.52; standard deviation ± 133.13) in relation to the adjacent breast tissue cells (189.59; standard deviation ± 140.75) was statistically larger (P fibroadenoma was positive and greater than in the adjacent breast tissue. Positive expression of the antigen in the adjacent breast tissue was influenced by parity, and was significantly more evident in nulliparous women.

Expression of antigen tf and galectin-3 in fibroadenoma.

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Gallegos, Itandehui Belem; Pérez-Campos, Eduardo; Martinez, Margarito; Mayoral, Miguel Ángel; Pérez, Laura; Aguilar, Sergio; Zenteno, Edgar; Pina, Maria del Socorro; Hernández, Pedro

2012-12-24

Fibroadenomas are benign human breast tumors, characterized by proliferation of epithelial and stromal components of the terminal ductal unit. They may grow, regress or remain unchanged, as the hormonal environment of the patient changes. Expression of antigen TF in mucin or mucin-type glycoproteins and of galectin-3 seems to contribute to proliferation and transformations events; their expression has been reported in ductal breast cancer and in aggressive tumors. Lectin histochemistry, immunohistochemistry, and immunofluorescence were used to examine the expression and distribution of antigen TF and galectin-3. We used lectins from Arachis hypogaea, Artocarpus integrifolia, and Amaranthus lecuocarpus to evaluate TF expression and a monoclonal antibody to evaluate galectin-3 expression. We used paraffin-embedded blocks from 10 breast tissues diagnosed with fibroadenoma and as control 10 healthy tissue samples. Histochemical and immunofluorescence analysis showed positive expression of galectin-3 in fibroadenoma tissue, mainly in stroma, weak interaction in ducts was observed; whereas, in healthy tissue samples the staining was also weak in ducts. Lectins from A. leucocarpus and A. integrifolia specificaly recognized ducts in healthy breast samples, whereas the lectin from A. hypogaea recognized ducts and stroma. In fibroadenoma tissue, the lectins from A. integrifolia, A. Hypogaea, and A. leucocarpus recognized mainly ducts. Our results suggest that expression of antigen TF and galectin-3 seems to participate in fibroadenoma development.

Expression of antigen tf and galectin-3 in fibroadenoma

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Gallegos Itandehui Belem

2012-12-01

Full Text Available Abstract Background Fibroadenomas are benign human breast tumors, characterized by proliferation of epithelial and stromal components of the terminal ductal unit. They may grow, regress or remain unchanged, as the hormonal environment of the patient changes. Expression of antigen TF in mucin or mucin-type glycoproteins and of galectin-3 seems to contribute to proliferation and transformations events; their expression has been reported in ductal breast cancer and in aggressive tumors. Findings Lectin histochemistry, immunohistochemistry, and immunofluorescence were used to examine the expression and distribution of antigen TF and galectin-3. We used lectins from Arachis hypogaea, Artocarpus integrifolia, and Amaranthus lecuocarpus to evaluate TF expression and a monoclonal antibody to evaluate galectin-3 expression. We used paraffin-embedded blocks from 10 breast tissues diagnosed with fibroadenoma and as control 10 healthy tissue samples. Histochemical and immunofluorescence analysis showed positive expression of galectin-3 in fibroadenoma tissue, mainly in stroma, weak interaction in ducts was observed; whereas, in healthy tissue samples the staining was also weak in ducts. Lectins from A. leucocarpus and A. integrifolia specificaly recognized ducts in healthy breast samples, whereas the lectin from A. hypogaea recognized ducts and stroma. In fibroadenoma tissue, the lectins from A. integrifolia, A. Hypogaea, and A. leucocarpus recognized mainly ducts. Conclusions Our results suggest that expression of antigen TF and galectin-3 seems to participate in fibroadenoma development.

The influence of concentration of inactivated Edwardsiella tarda bacterin and immersion time on antigen uptake and expression of immune-related genes in Japanese flounder (Paralichthys olivaceus).

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Du, Yang; Tang, Xiaoqian; Sheng, Xiuzhen; Xing, Jing; Zhan, Wenbin

2017-02-01

Our previous work has demonstrated that the immune response of Japanese flounder was associated with the concentration of formalin-inactivated Edwardsiella tarda and immersion time. In order to further investigate the influence of immersion vaccine dose and bath time on the antigen uptake, formalin-killed Edwardsiella tarda bacterin was prepared and adjusted to four concentrations (10 9 , 10 8 , 10 7 , 10 6  cfu ml -1 ) for 30, 60 and 90 min immersion in Japanese flounder model, respectively. Absolute quantitative real-time PCR was employed to examine the bacterin uptake in gill, skin, spleen and kidney at 3 and 6 h post vaccination. The results showed that the antigen uptaken in gills and skin were significant higher than spleen and kidney, and the antigen amounts in gill and skin both declined from 3 to 6 h, whereas the antigen amounts in spleen and kidney gradually increased. Significant higher antigen amounts were detected in 10 9 -30, 10 9 -60, 10 8 -60, 10 8 -90 and 10 8 -90 groups than other groups (P immersion with formalin-inactivated E. tarda, especially under 10 8 -60 min condition could efficiently enhance the antigen uptake and the expression of immune-related genes, which provided evidences for an enhanced vaccination effects under an optimized combination of vaccine dose and immersion time. Copyright © 2016 Elsevier Ltd. All rights reserved.

Plant bioreactors for the antigenic hook-associated flgK protein expression

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Luciana Rossi

2014-01-01

Full Text Available Plants engineered with genes encoding for the antigenic proteins of various microorganisms have shown to correctly express the proteins that elicit the production of antibodies in mammalian hosts. In livestock, plant-based vaccines could represent an innovative strategy for oral vaccination, especially to prevent infection by enteric pathogens. The aim of this study was to evaluate tobacco plants as a seedspecific expression system for the production of the flgK flagellar hook-associated protein from a wild type Salmonella typhimurium strain, as a model of an edible vaccine. The flgK gene is the principal component of bacterial flagella and is recognised as virulence factor by the innate immune system. It was isolated from the Salmonella typhimurium strain by PCR. The encoding sequence of flgK was transferred into a pBI binary vector, under control of soybean basic 7S globulin promoter for the seed-specific. Plant transformation was carried out using recombinant EHA 105 Agrobacterium tumefaciens. A transgenic population was obtained made up of independently kanamycin-resistant transgenic plants, which had a similar morphological appearance to the wild-type plants. Molecular analyses of seeds confirmed the integration of the gene and the average expression level of flgK was estimated to be about 0.6 mg per gram of seeds, corresponding to 0.33% of the total amount of soluble protein in tobacco seeds. This study showed that the foreign flgK gene could be stably incorporated into the tobacco plant genome by transcription through the nuclear apparatus of the plant, and that these genes are inherited by the next generation.

Adoptitive immunotherapy with genetically engineered T lymphocytes modified to express chimeric antigen receptors

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A. А. Pavlova

2017-01-01

Full Text Available Significant mortality due to oncological diseases as a whole, and oncohematological diseases in particular, motivates scientific and medical community to develop new treatment methods. One of the newest methods is adoptive cell therapy using patient’s own T-cells modified to express chimeric antigen receptors (CAR to tumor-specific antigens. Despite high cost and side effects of treatment, promising clinical trials even in patients with advanced disease allow to anticipate successful use of this method in clinical practice.The article includes a review of the main principles of this technique, published results of clinical studies of CAR T-cells with a focus on CD19 gene targeting, complications of this therapy, mechanisms of tumor resistance to CAR T-cells, and potential ways to overcome it.

Comparative immunological evaluation of recombinant Salmonella Typhimurium strains expressing model antigens as live oral vaccines.

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Zheng, Song-yue; Yu, Bin; Zhang, Ke; Chen, Min; Hua, Yan-Hong; Yuan, Shuofeng; Watt, Rory M; Zheng, Bo-Jian; Yuen, Kwok-Yung; Huang, Jian-Dong

2012-09-26

Despite the development of various systems to generate live recombinant Salmonella Typhimurium vaccine strains, little work has been performed to systematically evaluate and compare their relative immunogenicity. Such information would provide invaluable guidance for the future rational design of live recombinant Salmonella oral vaccines. To compare vaccine strains encoded with different antigen delivery and expression strategies, a series of recombinant Salmonella Typhimurium strains were constructed that expressed either the enhanced green fluorescent protein (EGFP) or a fragment of the hemagglutinin (HA) protein from the H5N1 influenza virus, as model antigens. The antigens were expressed from the chromosome, from high or low-copy plasmids, or encoded on a eukaryotic expression plasmid. Antigens were targeted for expression in either the cytoplasm or the outer membrane. Combinations of strategies were employed to evaluate the efficacy of combined delivery/expression approaches. After investigating in vitro and in vivo antigen expression, growth and infection abilities; the immunogenicity of the constructed recombinant Salmonella strains was evaluated in mice. Using the soluble model antigen EGFP, our results indicated that vaccine strains with high and stable antigen expression exhibited high B cell responses, whilst eukaryotic expression or colonization with good construct stability was critical for T cell responses. For the insoluble model antigen HA, an outer membrane expression strategy induced better B cell and T cell responses than a cytoplasmic strategy. Most notably, the combination of two different expression strategies did not increase the immune response elicited. Through systematically evaluating and comparing the immunogenicity of the constructed recombinant Salmonella strains in mice, we identified their respective advantages and deleterious or synergistic effects. Different construction strategies were optimally-required for soluble versus

Expression and immunogenicity of novel subunit enterovirus 71 VP1 antigens

International Nuclear Information System (INIS)

Xu, Juan; Wang, Shixia; Gan, Weihua; Zhang, Wenhong; Ju, Liwen; Huang, Zuhu; Lu, Shan

2012-01-01

Highlights: ► EV71 is a major emerging infectious disease in many Asian countries. ► Inactivated EV71 vaccines are in clinical studies but their safety and efficacy are unknown. ► Developing subunit based EV71 vaccines is significant and novel antigen design is needed. ► DNA immunization is an efficient tool to test the immunogenicity of VP1 based EV71 vaccines. ► Multiple VP1 antigens are developed showing immunogenic potential. -- Abstract: Hand, foot, and mouth disease (HFMD) is a common viral illness in young children. HFMD is caused by viruses belonging to the enterovirus genus of the picornavirus family. Recently, enterovirus 71 (EV71) has emerged as a virulent agent for HFMD with severe clinical outcomes. In the current report, we conducted a pilot antigen engineering study to optimize the expression and immunogenicity of subunit VP1 antigen for the design of EV71 vaccines. DNA immunization was adopted as a simple technical approach to test different designs of VP1 antigens without the need to express VP1 protein in vitro first. Our studies indicated that the expression and immunogenicity of VP1 protein can be improved with alternated VP1 antigen designs. Data presented in the current report revealed novel pathways to optimize the design of VP1 antigen-based EV71 vaccines.

[Optimization of prokaryotic expression conditions of Leptospira interrogans trigeminy genus-specific protein antigen based on surface response analysis].

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Wang, Jiang; Luo, Dongjiao; Sun, Aihua; Yan, Jie

2008-07-01

Lipoproteins LipL32 and LipL21 and transmembrane protein OMPL1 have been confirmed as the superficial genus-specific antigens of Leptospira interrogans, which can be used as antigens for developing a universal genetic engineering vaccine. In order to obtain high expression of an artificial fusion gene lipL32/1-lipL21-ompL1/2, we optimized prokaryotic expression conditions. We used surface response analysis based on the central composite design to optimize culture conditions of a new antigen protein by recombinant Escherichia coli DE3.The culture conditions included initial pH, induction start time, post-induction time, Isopropyl beta-D-thiogalactopyranoside (IPTG) concentration, and temperature. The maximal production of antigen protein was 37.78 mg/l. The optimal culture conditions for high recombinant fusion protein was determined: initial pH 7.9, induction start time 2.5 h, a post-induction time of 5.38 h, 0.20 mM IPTG, and a post-induction temperature of 31 degrees C. Surface response analysis based on CCD increased the target production. This statistical method reduced the number of experiments required for optimization and enabled rapid identification and integration of the key culture condition parameters for optimizing recombinant protein expression.

Cell-free translational screening of an expression sequence tag library of Clonorchis sinensis for novel antigen discovery.

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Kasi, Devi; Catherine, Christy; Lee, Seung-Won; Lee, Kyung-Ho; Kim, Yu Jung; Ro Lee, Myeong; Ju, Jung Won; Kim, Dong-Myung

2017-05-01

The rapidly evolving cloning and sequencing technologies have enabled understanding of genomic structure of parasite genomes, opening up new ways of combatting parasite-related diseases. To make the most of the exponentially accumulating genomic data, however, it is crucial to analyze the proteins encoded by these genomic sequences. In this study, we adopted an engineered cell-free protein synthesis system for large-scale expression screening of an expression sequence tag (EST) library of Clonorchis sinensis to identify potential antigens that can be used for diagnosis and treatment of clonorchiasis. To allow high-throughput expression and identification of individual genes comprising the library, a cell-free synthesis reaction was designed such that both the template DNA and the expressed proteins were co-immobilized on the same microbeads, leading to microbead-based linkage of the genotype and phenotype. This reaction configuration allowed streamlined expression, recovery, and analysis of proteins. This approach enabled us to identify 21 antigenic proteins. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:832-837, 2017. © 2017 American Institute of Chemical Engineers.

Genetical and functional investigation of fliC genes encoding flagellar serotype H4 in wildtype strains of Escherichia coli and in a laboratory E. coli K-12 strain expressing flagellar antigen type H48

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Schaudinn Christoph

2005-01-01

Full Text Available Abstract Background Serotyping of O-(lipopolysaccharide and H-(flagellar antigens is a wideley used method for identification of pathogenic strains and clones of Escherichia coli. At present, 176 O- and 53 H-antigens are described for E. coli which occur in different combinations in the strains. The flagellar antigen H4 is widely present in E. coli strains of different O-serotypes and pathotypes and we have investigated the genetic relationship between H4 encoding fliC genes by PCR, nucleotide sequencing and expression studies. Results The complete nucleotide sequence of fliC genes present in E. coli reference strains U9-41 (O2:K1:H4 and P12b (O15:H17 was determined and both were found 99.3% (1043 of 1050 nucleotides identical in their coding sequence. A PCR/RFLP protocol was developed for typing of fliC-H4 strains and 88 E. coli strains reacting with H4 antiserum were investigated. Nucleotide sequencing of complete fliC genes of six E. coli strains which were selected based on serum agglutination titers, fliC-PCR genotyping and reference data revealed 96.6 to 100% identity on the amino acid level. The functional expression of flagellin encoded by fliC-H4 from strain U9-41 and from our strain P12b which is an H4 expressing variant type was investigated in the E. coli K-12 strain JM109 which encodes flagellar type H48. The fliC recombinant plasmid carrying JM109 strains reacted with both H4 and H48 specific antisera whereas JM109 reacted only with the H48 antiserum. By immunoelectron microscopy, we could show that the flagella made by the fliC-H4 recombinant plasmid carrying strain are constituted of H48 and H4 flagellins which are co-assembled into functional flagella. Conclusion The flagellar serotype H4 is encoded by closely related fliC genes present in serologically different types of E. coli strainswhich were isolated at different time periods and geographical locations. Our expression studies show for the first time, that flagellins of

Expression of HIV-1 antigens in plants as potential subunit vaccines

CSIR Research Space (South Africa)

Meyers, A

2008-06-23

Full Text Available Open AcceResearch article Expression of HIV-1 antigens in plants as potential subunit vaccines Ann Meyers1,2, Ereck Chakauya1,2,3, Enid Shephard1,4, Fiona L Tanzer1,2, James Maclean1,2, Alisson Lynch1,2, Anna-Lise Williamson1,5 and Edward P Rybicki...Figure 1 The HIV-1 Gag-derived proteins used in this study. Scale diagram showing (A) native Pr55Gag ORF organisation in the Page 2 of 15 (page number not for citation purposes) gag gene, (B) the p17/p24 fusion protein ORF, (C) p24 ORF. ORFs labelled p7...

Purification and refolding of anti-T-antigen single chain antibodies (scFvs) expressed in Escherichia coli as inclusion bodies.

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Yuasa, Noriyuki; Koyama, Tsubasa; Fujita-Yamaguchi, Yoko

2014-02-01

T-antigen (Galβ1-3GalNAcα-1-Ser/Thr) is an oncofetal antigen that is commonly expressed as a carbohydrate determinant in many adenocarcinomas. Since it is associated with tumor progression and metastasis, production of recombinant antibodies specific for T-antigen could lead to the development of cancer diagnostics and therapeutics. Previously, we isolated and characterized 11 anti-T-antigen phage clones from a phage library displaying human single-chain antibodies (scFvs) and purified one scFv protein, 1G11. More recently, we purified and characterized 1E8 scFv protein using a Drosophila S2 expression system. In the current study, four anti-T-antigen scFv genes belonging to Groups 1-4 were purified from inclusion bodies expressed in Escherichia coli cells. Inclusion bodies isolated from E. coli cells were denatured in 3.5 M Gdn-HCl. Solubilized His-tagged scFv proteins were purified using Ni(2+)-Sepharose column chromatography in the presence of 3.5 M Gdn-HCl. Purified scFv proteins were refolded according to a previously published method of step-wise dialysis. Two anti-T-antigen scFv proteins, 1E6 and 1E8 that belong to Groups 1 and 2, respectively, were produced in sufficient amounts, thus allowing further characterization of their binding activity with T-antigen. Specificity and affinity constants determined using enzyme-linked immunosorbent assay (ELISA) and surface plasmon resonance (SPR), respectively, provided evidence that both 1E8 and 1E6 scFv proteins are T-antigen specific and suggested that 1E8 scFv protein has a higher affinity for T-antigen than 1E6 scFv protein.

Expression and immunogenicity of novel subunit enterovirus 71 VP1 antigens

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Xu, Juan [China-US Vaccine Research Center, The First Affiliated Hospital, Nanjing Medical University (China); Department of Microbiology and Immunology, Nanjing Medical University (China); Wang, Shixia [China-US Vaccine Research Center, The First Affiliated Hospital, Nanjing Medical University (China); Department of Medicine, University of Massachusetts Medical School (United States); Gan, Weihua [Department of Pediatrics, The Second Affiliated Hospital, Nanjing Medical University (China); Zhang, Wenhong [Department of Infectious Diseases, Huashan Hospital, Fudan University (China); Ju, Liwen [School of Public Health, Fudan University (China); Huang, Zuhu [Department of Infectious Diseases, The First Affiliated Hospital, Nanjing Medical University (China); China-US Vaccine Research Center, The First Affiliated Hospital, Nanjing Medical University (China); Lu, Shan, E-mail: shan.lu@umassmed.edu [Department of Infectious Diseases, The First Affiliated Hospital, Nanjing Medical University (China); China-US Vaccine Research Center, The First Affiliated Hospital, Nanjing Medical University (China); Department of Medicine, University of Massachusetts Medical School (United States)

2012-04-20

Highlights: Black-Right-Pointing-Pointer EV71 is a major emerging infectious disease in many Asian countries. Black-Right-Pointing-Pointer Inactivated EV71 vaccines are in clinical studies but their safety and efficacy are unknown. Black-Right-Pointing-Pointer Developing subunit based EV71 vaccines is significant and novel antigen design is needed. Black-Right-Pointing-Pointer DNA immunization is an efficient tool to test the immunogenicity of VP1 based EV71 vaccines. Black-Right-Pointing-Pointer Multiple VP1 antigens are developed showing immunogenic potential. -- Abstract: Hand, foot, and mouth disease (HFMD) is a common viral illness in young children. HFMD is caused by viruses belonging to the enterovirus genus of the picornavirus family. Recently, enterovirus 71 (EV71) has emerged as a virulent agent for HFMD with severe clinical outcomes. In the current report, we conducted a pilot antigen engineering study to optimize the expression and immunogenicity of subunit VP1 antigen for the design of EV71 vaccines. DNA immunization was adopted as a simple technical approach to test different designs of VP1 antigens without the need to express VP1 protein in vitro first. Our studies indicated that the expression and immunogenicity of VP1 protein can be improved with alternated VP1 antigen designs. Data presented in the current report revealed novel pathways to optimize the design of VP1 antigen-based EV71 vaccines.

Expression analysis of cancer-testis genes in prostate cancer reveals candidates for immunotherapy.

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Faramarzi, Sepideh; Ghafouri-Fard, Soudeh

2017-09-01

Prostate cancer is a prevalent disorder among men with a heterogeneous etiological background. Several molecular events and signaling perturbations have been found in this disorder. Among genes whose expressions have been altered during the prostate cancer development are cancer-testis antigens (CTAs). This group of antigens has limited expression in the normal adult tissues but aberrant expression in cancers. This property provides them the possibility to be used as cancer biomarkers and immunotherapeutic targets. Several CTAs have been shown to be immunogenic in prostate cancer patients and some of the have entered clinical trials. Based on the preliminary data obtained from these trials, it is expected that CTA-based therapeutic options are beneficial for at least a subset of prostate cancer patients.

Cell-Free Expression and In Situ Immobilization of Parasite Proteins from Clonorchis sinensis for Rapid Identification of Antigenic Candidates.

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Christy Catherine

Full Text Available Progress towards genetic sequencing of human parasites has provided the groundwork for a post-genomic approach to develop novel antigens for the diagnosis and treatment of parasite infections. To fully utilize the genomic data, however, high-throughput methodologies are required for functional analysis of the proteins encoded in the genomic sequences. In this study, we investigated cell-free expression and in situ immobilization of parasite proteins as a novel platform for the discovery of antigenic proteins. PCR-amplified parasite DNA was immobilized on microbeads that were also functionalized to capture synthesized proteins. When the microbeads were incubated in a reaction mixture for cell-free synthesis, proteins expressed from the microbead-immobilized DNA were instantly immobilized on the same microbeads, providing a physical linkage between the genetic information and encoded proteins. This approach of in situ expression and isolation enables streamlined recovery and analysis of cell-free synthesized proteins and also allows facile identification of the genes coding antigenic proteins through direct PCR of the microbead-bound DNA.

Characterization of a transcriptional promoter of human papillomavirus 18 and modulation of its expression by simian virus 40 and adenovirus early antigens

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Thierry, F.; Heard, J.M.; Dartmann, K.; Yaniv, M.

1987-01-01

RNA present in cells derived from cervical carcinoma that contained human papillomavirus 18 genomes was initiated in the 1.053-kilobase BamHI fragment that covered the complete noncoding region of this virus. When cloned upstream of the chloramphenicol acetyltransferase gene, this viral fragment directed the expression of the bacterial enzyme only in the sense orientation. Initiation sites were mapped around the ATG of open reading frame E6. This promoter was active in some human and simian cell lines, and its expression was modulated positively by simian virus 40 large T antigen and negatively by adenovirus type 5 E1a antigen

Intersex related gene expression profiles in clams Scrobicularia plana: Molecular markers and environmental application

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Ciocan, Corina M.; Cubero-Leon, Elena; Langston, William J.; Pope, Nick; Cornelius, Keith; Hill, E.M.; Alvarez-Munoz, Diana; Indiveri, Paolo; Lerebours, Adelaide; Minier, Christophe; Rotchell, Jeanette M.

2015-01-01

Highlights: • Expression of intersex-related genes was analysed in clam gonads sampled from the Channel. • Genes were differentially expressed at sites with varying levels of intersex and contaminants. • Correlations between gene expressions, key contaminants and sampling sites were identified. • No single gene expression studied correlated with intersex incidence. - Abstract: Intersex, the appearance of female characteristics in male gonads, has been identified in several aquatic species. It is a widespread phenomenon in populations of the bivalve, Scrobicularia plana, from the southwest coast of the U.K. Genes previously identified as differentially expressed (ferritin, testicular haploid expressed gene, THEG, proliferating cell nuclear antigen, PCNA; receptor activated protein kinase C, RACK; cytochrome B, CYB; and cytochrome c oxidase 1, COX1) in intersex clams relative to normal male clams, were selected for characterisation and an environmental survey of the Channel region. Transcripts were significantly differentially expressed at sites with varying intersex incidence and contaminant burdens. Significant correlations between specific gene expressions, key contaminants and sampling locations have been identified, though no single gene was associated with intersex incidence. The results highlight the difficulty in understanding the intersex phenomenon in molluscs where there is still a lack of knowledge on the control of normal reproduction

Gene expression analysis after receptor tyrosine kinase activation reveals new potential melanoma proteins

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Teutschbein, Janka; Haydn, Johannes M; Samans, Birgit; Krause, Michael; Eilers, Martin; Schartl, Manfred; Meierjohann, Svenja

2010-01-01

Melanoma is an aggressive tumor with increasing incidence. To develop accurate prognostic markers and targeted therapies, changes leading to malignant transformation of melanocytes need to be understood. In the Xiphophorus melanoma model system, a mutated version of the EGF receptor Xmrk (Xiphophorus melanoma receptor kinase) triggers melanomagenesis. Cellular events downstream of Xmrk, such as the activation of Akt, Ras, B-Raf or Stat5, were also shown to play a role in human melanomagenesis. This makes the elucidation of Xmrk downstream targets a useful method for identifying processes involved in melanoma formation. Here, we analyzed Xmrk-induced gene expression using a microarray approach. Several highly expressed genes were confirmed by realtime PCR, and pathways responsible for their induction were revealed using small molecule inhibitors. The expression of these genes was also monitored in human melanoma cell lines, and the target gene FOSL1 was knocked down by siRNA. Proliferation and migration of siRNA-treated melanoma cell lines were then investigated. Genes with the strongest upregulation after receptor activation were FOS-like antigen 1 (Fosl1), early growth response 1 (Egr1), osteopontin (Opn), insulin-like growth factor binding protein 3 (Igfbp3), dual-specificity phosphatase 4 (Dusp4), and tumor-associated antigen L6 (Taal6). Interestingly, most genes were blocked in presence of a SRC kinase inhibitor. Importantly, we found that FOSL1, OPN, IGFBP3, DUSP4, and TAAL6 also exhibited increased expression levels in human melanoma cell lines compared to human melanocytes. Knockdown of FOSL1 in human melanoma cell lines reduced their proliferation and migration. Altogether, the data show that the receptor tyrosine kinase Xmrk is a useful tool in the identification of target genes that are commonly expressed in Xmrk-transgenic melanocytes and melanoma cell lines. The identified molecules constitute new possible molecular players in melanoma development

Gene expression analysis after receptor tyrosine kinase activation reveals new potential melanoma proteins

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Krause Michael

2010-07-01

Full Text Available Abstract Background Melanoma is an aggressive tumor with increasing incidence. To develop accurate prognostic markers and targeted therapies, changes leading to malignant transformation of melanocytes need to be understood. In the Xiphophorus melanoma model system, a mutated version of the EGF receptor Xmrk (Xiphophorus melanoma receptor kinase triggers melanomagenesis. Cellular events downstream of Xmrk, such as the activation of Akt, Ras, B-Raf or Stat5, were also shown to play a role in human melanomagenesis. This makes the elucidation of Xmrk downstream targets a useful method for identifying processes involved in melanoma formation. Methods Here, we analyzed Xmrk-induced gene expression using a microarray approach. Several highly expressed genes were confirmed by realtime PCR, and pathways responsible for their induction were revealed using small molecule inhibitors. The expression of these genes was also monitored in human melanoma cell lines, and the target gene FOSL1 was knocked down by siRNA. Proliferation and migration of siRNA-treated melanoma cell lines were then investigated. Results Genes with the strongest upregulation after receptor activation were FOS-like antigen 1 (Fosl1, early growth response 1 (Egr1, osteopontin (Opn, insulin-like growth factor binding protein 3 (Igfbp3, dual-specificity phosphatase 4 (Dusp4, and tumor-associated antigen L6 (Taal6. Interestingly, most genes were blocked in presence of a SRC kinase inhibitor. Importantly, we found that FOSL1, OPN, IGFBP3, DUSP4, and TAAL6 also exhibited increased expression levels in human melanoma cell lines compared to human melanocytes. Knockdown of FOSL1 in human melanoma cell lines reduced their proliferation and migration. Conclusion Altogether, the data show that the receptor tyrosine kinase Xmrk is a useful tool in the identification of target genes that are commonly expressed in Xmrk-transgenic melanocytes and melanoma cell lines. The identified molecules constitute

Phenotypic H-Antigen Typing by Mass Spectrometry Combined with Genetic Typing of H Antigens, O Antigens, and Toxins by Whole-Genome Sequencing Enhances Identification of Escherichia coli Isolates.

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Cheng, Keding; Chui, Huixia; Domish, Larissa; Sloan, Angela; Hernandez, Drexler; McCorrister, Stuart; Robinson, Alyssia; Walker, Matthew; Peterson, Lorea A M; Majcher, Miles; Ratnam, Sam; Haldane, David J M; Bekal, Sadjia; Wylie, John; Chui, Linda; Tyler, Shaun; Xu, Bianli; Reimer, Aleisha; Nadon, Celine; Knox, J David; Wang, Gehua

2016-08-01

Mass spectrometry-based phenotypic H-antigen typing (MS-H) combined with whole-genome-sequencing-based genetic identification of H antigens, O antigens, and toxins (WGS-HOT) was used to type 60 clinical Escherichia coli isolates, 43 of which were previously identified as nonmotile, H type undetermined, or O rough by serotyping or having shown discordant MS-H and serotyping results. Whole-genome sequencing confirmed that MS-H was able to provide more accurate data regarding H antigen expression than serotyping. Further, enhanced and more confident O antigen identification resulted from gene cluster based typing in combination with conventional typing based on the gene pair comprising wzx and wzy and that comprising wzm and wzt The O antigen was identified in 94.6% of the isolates when the two genetic O typing approaches (gene pair and gene cluster) were used in conjunction, in comparison to 78.6% when the gene pair database was used alone. In addition, 98.2% of the isolates showed the existence of genes for various toxins and/or virulence factors, among which verotoxins (Shiga toxin 1 and/or Shiga toxin 2) were 100% concordant with conventional PCR based testing results. With more applications of mass spectrometry and whole-genome sequencing in clinical microbiology laboratories, this combined phenotypic and genetic typing platform (MS-H plus WGS-HOT) should be ideal for pathogenic E. coli typing. Copyright © 2016 Cheng et al.

Expression and the antigenicity of recombinant coat proteins of tungro viruses expressed in Escherichia coli.

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Yee, Siew Fung; Chu, Chia Huay; Poili, Evenni; Sum, Magdline Sia Henry

2017-02-01

Rice tungro disease (RTD) is a recurring disease affecting rice farming especially in the South and Southeast Asia. The disease is commonly diagnosed by visual observation of the symptoms on diseased plants in paddy fields and by polymerase chain reaction (PCR). However, visual observation is unreliable and PCR can be costly. High-throughput as well as relatively cheap detection methods are important for RTD management for screening large number of samples. Due to this, detection by serological assays such as immunoblotting assays and enzyme-linked immunosorbent assay are preferred. However, these serological assays are limited by lack of continuous supply of antibodies as reagents due to the difficulty in preparing sufficient purified virions as antigens. This study aimed to generate and evaluate the reactivity of the recombinant coat proteins of Rice tungro bacilliform virus (RTBV) and Rice tungro spherical virus (RTSV) as alternative antigens to generate antibodies. The genes encoding the coat proteins of both viruses, RTBV (CP), and RTSV (CP1, CP2 and CP3) were cloned and expressed as recombinant fusion proteins in Escherichia coli. All of the recombinant fusion proteins, with the exception of the recombinant fusion protein of the CP2 of RTSV, were reactive against our in-house anti-tungro rabbit serum. In conclusion, our study showed the potential use of the recombinant fusion coat proteins of the tungro viruses as alternative antigens for production of antibodies for diagnostic purposes. Copyright © 2016 Elsevier B.V. All rights reserved.

[Study of testicular cancer gene expression in samples of oral leukoplakia and squamous cell carcinoma of the mouth].

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Skorodumova, L O; Muraev, A A; Zakharova, E S; Shepelev, M V; Korobko, I V; Zaderenko, I A; Ivanov, S Iu; Gnuchev, N V; Georgiev, G P; Larin, S S

2012-01-01

Cancer-testis (CT) antigens are normally expressed mostly in human germ cells, there is also an aberrant expression in some tumor cells. This expression profile makes them potential tumor growth biomarkers and a promising target for tumor immunotherapy. Specificity of CT genes expression in oral malignant and potentially malignant diseases, e.g. oral leukoplakia, is not yet studied. Data on CT genes expression profile in leukoplakia would allow developing new diagnostic methods with potential value for immunotherapy and prophylaxis of leukoplakia malignization. In our study we compared CT genes expression in normal oral mucosa, oral leukoplakia and oral squamous cell carcinoma. We are the first to describe CT genes expression in oral leukoplakia without dysplasia. This findings make impossible differential diagnosis of oral leukoplakia and squamous cell carcinoma on the basis of CT genes expression. The prognostic value of CT genes expression is still unclear, therefore the longitudinal studies are necessary.

The porcine circovirus type 1 capsid gene promoter improves antigen expression and immunogenicity in a HIV-1 plasmid vaccine

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Burger Marieta

2011-02-01

Full Text Available Abstract Background One of the promising avenues for development of vaccines against Human immunodeficiency virus type 1 (HIV-1 and other human pathogens is the use of plasmid-based DNA vaccines. However, relatively large doses of plasmid must be injected for a relatively weak response. We investigated whether genome elements from Porcine circovirus type 1 (PCV-1, an apathogenic small ssDNA-containing virus, had useful expression-enhancing properties that could allow dose-sparing in a plasmid vaccine. Results The linearised PCV-1 genome inserted 5' of the CMV promoter in the well-characterised HIV-1 plasmid vaccine pTHgrttnC increased expression of the polyantigen up to 2-fold, and elicited 3-fold higher CTL responses in mice at 10-fold lower doses than unmodified pTHgrttnC. The PCV-1 capsid gene promoter (Pcap alone was equally effective. Enhancing activity was traced to a putative composite host transcription factor binding site and a "Conserved Late Element" transcription-enhancing sequence previously unidentified in circoviruses. Conclusions We identified a novel PCV-1 genome-derived enhancer sequence that significantly increased antigen expression from plasmids in in vitro assays, and improved immunogenicity in mice of the HIV-1 subtype C vaccine plasmid, pTHgrttnC. This should allow significant dose sparing of, or increased responses to, this and other plasmid-based vaccines. We also report investigations of the potential of other circovirus-derived sequences to be similarly used.

Antigenic determinants and functional domains in core antigen and e antigen from hepatitis B virus

International Nuclear Information System (INIS)

Salfeld, J.; Pfaff, E.; Noah, M.; Schaller, H.

1989-01-01

The precore/core gene of hepatitis B virus directs the synthesis of two polypeptides, the 21-kilodalton subunit (p21c) forming the viral nucleocapsid (serologically defined as core antigen [HBcAg]) and a secreted processed protein (p17e, serologically defined as HBe antigen [HBeAg]). Although most of their primary amino acid sequences are identical, HBcAg and HBeAg display different antigenic properties that are widely used in hepatitis B virus diagnosis. To locate and to characterize the corresponding determinants, segments of the core gene were expressed in Escherichia coli and probed with a panel of polyclonal or monoclonal antibodies in radioimmunoassays or enzyme-linked immunosorbent assays, Western blots, and competition assays. Three distinct major determinants were characterized. It is postulated that HBcAg and HBeAg share common basic three-dimensional structure exposing the common linear determinant HBe1 but that they differ in the presentation of two conformational determinants that are either introduced (HBc) or masked (HBe2) in the assembled core. The simultaneous presentation of HBe1 and HBc, two distinctly different antigenic determinants with overlapping amino acid sequences, is interpreted to indicate the presence of slightly differently folded, stable conformational states of p21c in the hepatitis virus nucleocapsid

Gene expression and gene therapy imaging

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Rome, Claire; Couillaud, Franck; Moonen, Chrit T.W.

2007-01-01

The fast growing field of molecular imaging has achieved major advances in imaging gene expression, an important element of gene therapy. Gene expression imaging is based on specific probes or contrast agents that allow either direct or indirect spatio-temporal evaluation of gene expression. Direct evaluation is possible with, for example, contrast agents that bind directly to a specific target (e.g., receptor). Indirect evaluation may be achieved by using specific substrate probes for a target enzyme. The use of marker genes, also called reporter genes, is an essential element of MI approaches for gene expression in gene therapy. The marker gene may not have a therapeutic role itself, but by coupling the marker gene to a therapeutic gene, expression of the marker gene reports on the expression of the therapeutic gene. Nuclear medicine and optical approaches are highly sensitive (detection of probes in the picomolar range), whereas MRI and ultrasound imaging are less sensitive and require amplification techniques and/or accumulation of contrast agents in enlarged contrast particles. Recently developed MI techniques are particularly relevant for gene therapy. Amongst these are the possibility to track gene therapy vectors such as stem cells, and the techniques that allow spatiotemporal control of gene expression by non-invasive heating (with MRI guided focused ultrasound) and the use of temperature sensitive promoters. (orig.)

Low expression of a few genes indicates good prognosis in estrogen receptor positive breast cancer

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Buechler Steven

2009-07-01

Full Text Available Abstract Background Many breast cancer patients remain free of distant metastasis even without adjuvant chemotherapy. While standard histopathological tests fail to identify these good prognosis patients with adequate precision, analyses of gene expression patterns in primary tumors have resulted in more successful diagnostic tests. These tests use continuous measurements of the mRNA concentrations of numerous genes to determine a risk of metastasis in lymph node negative breast cancer patients with other clinical traits. Methods A survival model is constructed from genes that are both connected with relapse and have expression patterns that define distinct subtypes, suggestive of different cellular states. This in silico study uses publicly available microarray databases generated with Affymetrix GeneChip technology. The genes in our model, as represented by array probes, have distinctive distributions in a patient cohort, consisting of a large normal component of low expression values; and a long right tail of high expression values. The cutoff between low and high expression of a probe is determined from the distribution using the theory of mixture models. The good prognosis group in our model consists of the samples in the low expression component of multiple genes. Results Here, we define a novel test for risk of metastasis in estrogen receptor positive (ER+ breast cancer patients, using four probes that determine distinct subtypes. The good prognosis group in this test, denoted AP4-, consists of the samples with low expression of each of the four probes. Two probes target MKI67, antigen identified by monoclonal antibody Ki-67, one targets CDC6, cell division cycle 6 homolog (S. cerevisiae, and a fourth targets SPAG5, sperm associated antigen 5. The long-term metastasis-free survival probability for samples in AP4- is sufficiently high to render chemotherapy of questionable benefit. Conclusion A breast cancer subtype defined by low

A Lactococcus lactis BFE920 feed vaccine expressing a fusion protein composed of the OmpA and FlgD antigens from Edwardsiella tarda was significantly better at protecting olive flounder (Paralichthys olivaceus) from edwardsiellosis than single antigen vaccines.

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Beck, Bo Ram; Lee, Soon Ho; Kim, Daniel; Park, Ji Hye; Lee, Hyun Kyung; Kwon, San-Sung; Lee, Kwan Hee; Lee, Jae Il; Song, Seong Kyu

2017-09-01

Edwardsiellosis is a major fish disease that causes a significant economic damage in the aquaculture industry. Here, we assessed vaccine efficacy after feeding oral vaccines to olive flounder (Paralichthys olivaceus), either L. lactis BFE920 expressing Edwardsiella tarda outer membrane protein A (OmpA), flagellar hook protein D (FlgD), or a fusion antigen of the two. Feed vaccination was done twice with a one-week interval. Fish were fed regular feed adsorbed with the vaccines. Feed vaccination was given over the course of one week to maximize the interaction between the feed vaccines and the fish intestine. Flounder fed the vaccine containing the fusion antigen had significantly elevated levels T cell genes (CD4-1, CD4-2, and CD8α), type 1 helper T cell (Th1) subset indicator genes (T-bet and IFN-γ), and antigen-specific antibodies compared to the groups fed the single antigen-expressing vaccines. Furthermore, the superiority of the fusion vaccine was also observed in survival rates when fish were challenged with E. tarda: OmpA-FlgD-expressing vaccine (82.5% survival); FlgD-vaccine (55.0%); OmpA-vaccine (50%); WT L. lactis BFE920 (37.5%); Ctrl (10%). In addition, vaccine-fed fish exhibited increased weight gain (∼20%) and a decreased feed conversion ratio (∼20%) during the four week vaccination period. Flounder fed the FlgD-expressing vaccine, either the single or the fusion form, had significantly increased expression of TLR5M, IL-1β, and IL-12p40, suggesting that the FlgD may be a ligand of olive flounder TLR5M receptor or closely related to the TLR5M pathway. In conclusion, the present study demonstrated that olive flounder fed L. lactis BFE920 expressing a fusion antigen composed of E. tarda OmpA and FlgD showed a strong protective effect against edwardsiellosis indicating this may be developed as an E. tarda feed vaccine. Copyright © 2017 Elsevier Ltd. All rights reserved.

Gene expression pattern at different time points following ALA-PDT

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Verwanger, T.; Sanovic, R.; Ruhdorfer, S.; Aberger, F.; Frischauf, A.; Krammer, B.

2003-01-01

Full text: The photo sensitizer protoporphyrin IX, endogenously accumulated from the precursor aminolevulinic acid (ALA), is a successful agent in photodynamic tumor therapy. In spite of encouraging clinical results, the basic mechanisms leading to cell death are not fully understood. We therefore set out to analyze the alteration of the gene expression pattern in the squamous cell carcinoma cell line A-431 at different time points after photodynamic treatment with endogenous protoporphyrin IX by cDNA-array technique. Cells were incubated for 16 hours with 100 μg/ml ALA and irradiated with a fluence of 3.5 J/cm 2 resulting in 50 % survival until 8 hours post treatment. RNA was isolated at 1.5, 3, 5 and 8 hours post treatment as well as of 3 controls (untreated, light only and dark), radioactively labelled by reverse transcription with 33P-dCTP and hybridized onto macroarray PCR filters containing PCR products of 2135 genes, which were selected for relevance in tumors, stress response and signal transduction. Verification of observed expression changes was carried out by real time PCR. We found a strong induction of expression of immediate early genes like c-fos as well as decreased expression of genes involved in proliferation like myc and the proliferating cell nuclear antigen (PCNA). (author)

Reactivity of some mammalian sera with the bovine leukaemia virus env gene polypeptide expressed in Escherichia coli

International Nuclear Information System (INIS)

Slavikova, K.; Zajac, V.

1989-01-01

Sera from bovine leukaemia virus (BLV)-infected cattle and sheep were tested by radioimmunoassay and Western blot for their reactivity with 60,000 protein coded by the env gene of BLV and expressed in Escherichia coli. This protein, antigenically similar to BLV protein, reacted with antibodies against BLV antigens in the sera tested. (author). 3 figs., 1 tab., 13 refs

Expression of blood group antigens A and B in pancreas of vertebrates

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ELENKA GEORGIEVA

2012-01-01

Full Text Available The biological role of blood group antigens (BGA A and B in tissues of different vertebrates is still controversial. There are few investigations on vertebrate pancreas and no obvious explanation of their tissue expression. The aim of the present study is to follow and compare the pancreatic expression of BGA A and B in representatives of five vertebrate classes. The biotin-streptavidin-proxidase labeling system was used for immunohistochemical detection of BGA by monoclonal antibodies to human A and B antigens. The present study reveals specific immunoreactivity in acinar and epithelial cells of pancreatic efferent ducts in species free-living vertebrates. The immunoperoxidase staining shows antigenic heterogeneity in the cellular localization. The number of positive cells and the intensity of expression vary in different species. Endothelial cells are positive only in the pancreas of Emys orbicularis. The lack of BGA A and B in some species suggests that the expression of these antigens is dependent not only on the evolutionary level of the species, but mainly on some genetic control mechanisms. The production of BGA A and B and the variability in their cellular localization probably reflect the stage of cell differentiation and the mechanisms of pancreatic secretor function. The presence of histo BGA in endodermal acinar pancreatic cells confirms the assumption for the high antigenic stability and conservatism of these molecules in vertebrate histogenesis and evolution.

Molecular characterisation and the protective immunity evaluation of Eimeria maxima surface antigen gene.

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Liu, Tingqi; Huang, Jingwei; Li, Yanlin; Ehsan, Muhammad; Wang, Shuai; Zhou, Zhouyang; Song, Xiaokai; Yan, Ruofeng; Xu, Lixin; Li, Xiangrui

2018-05-30

Coccidiosis is recognised as a major parasitic disease in chickens. Eimeria maxima is considered as a highly immunoprotective species within the Eimeria spp. family that infects chickens. In the present research, the surface antigen gene of E. maxima (EmSAG) was cloned, and the ability of EmSAG to stimulate protection against E. maxima was evaluated. Prokaryotic and eukaryotic plasmids expressing EmSAG were constructed. The EmSAG transcription and expression in vivo was performed based on the RT-PCR and immunoblot analysis. The expression of EmSAG in sporozoites and merozoites was detected through immunofluorescence analyses. The immune protection was assessed based on challenge experiments. Flow cytometry assays were used to determine the T cell subpopulations. The serum antibody and cytokine levels were evaluated by ELISA. The open reading frame (ORF) of EmSAG gene contained 645 bp encoding 214 amino acid residues. The immunoblot and RT-PCR analyses indicated that the EmSAG gene were transcribed and expressed in vivo. The EmSAG proteins were expressed in sporozoite and merozoite stages of E. maxima by the immunofluorescence assay. Challenge experiments showed that both pVAX1-SAG and the recombinant EmSAG (rEmSAG) proteins were successful in alleviating jejunal lesions, decreasing loss of body weight and the oocyst ratio. Additionally, these experiments possessed anticoccidial indices (ACI) of more than 170. Higher percentages of CD4 + and CD8 + T cells were detected in both EmSAG-inoculated birds than those of the negative control groups (P maxima.

Multiple Sclerosis Risk Variant HLA-DRB1*1501 Associates with High Expression of DRB1 Gene in Different Human Populations

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Abad-Grau, María del Mar; Fedetz, María; Izquierdo, Guillermo; Lucas, Miguel; Fernández, Óscar; Ndagire, Dorothy; Catalá-Rabasa, Antonio; Ruiz, Agustín; Gayán, Javier; Delgado, Concepción; Arnal, Carmen

2012-01-01

The human leukocyte antigen (HLA) DRB1*1501 has been consistently associated with multiple sclerosis (MS) in nearly all populations tested. This points to a specific antigen presentation as the pathogenic mechanism though this does not fully explain the disease association. The identification of expression quantitative trait loci (eQTL) for genes in the HLA locus poses the question of the role of gene expression in MS susceptibility. We analyzed the eQTLs in the HLA region with respect to MS-associated HLA-variants obtained from genome-wide association studies (GWAS). We found that the Tag of DRB1*1501, rs3135388 A allele, correlated with high expression of DRB1, DRB5 and DQB1 genes in a Caucasian population. In quantitative terms, the MS-risk AA genotype carriers of rs3135388 were associated with 15.7-, 5.2- and 8.3-fold higher expression of DQB1, DRB5 and DRB1, respectively, than the non-risk GG carriers. The haplotype analysis of expression-associated variants in a Spanish MS cohort revealed that high expression of DRB1 and DQB1 alone did not contribute to the disease. However, in Caucasian, Asian and African American populations, the DRB1*1501 allele was always highly expressed. In other immune related diseases such as type 1 diabetes, inflammatory bowel disease, ulcerative colitis, asthma and IgA deficiency, the best GWAS-associated HLA SNPs were also eQTLs for different HLA Class II genes. Our data suggest that the DR/DQ expression levels, together with specific structural properties of alleles, seem to be the causal effect in MS and in other immunopathologies rather than specific antigen presentation alone. PMID:22253788

Enhanced specificity in immunoscreening of expression cDNA clones using radiolabeled antigen overlay

International Nuclear Information System (INIS)

Chao, S.; Chao, L.; Chao, J.

1989-01-01

A highly sensitive and specific method has been developed for immunoscreening clones from an expression cDNA library. The procedures utilize a radiolabeled antigen detection method described originally for the immunoblotting of plasma proteins. Screening of rat alpha 1-antitrypsin clones was used. Comparison between Western blots of alpha 1-antitrypsin using both labeled antigen and protein A detection methods showed that the former yielded lower background and greater sensitivity than the latter. Further, this technique was shown to have a lower detection limit of less than 20 ng through Western blot analysis of varying concentrations of alpha 1-antitrypsin. The procedures are based on the expression of the protein by cDNA clones containing the DNA inserts in the correct reading frame. Following the transfer of phage proteins to nitrocellulose membranes, the bivalent antibodies bind monovalently to both nitrocellulose-bound-antigen in the phage lysates and radiolabeled antigen. The radiolabeled antigen overlay method is superior to the protein A detection method in sensitivity, specificity and reproducibility. This improved method can be applied in general for screening expression cDNA libraries, provided that the specific antiserum and radiolabeled antigen are available

Liver cancer: expression features of hepatitis B antigens

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V. A. Tumanskiy

2013-12-01

Full Text Available Introduction. Hepatocellular carcinoma (HCC is currently the fifth most common malignancy in men and the eighth in women worldwide. According to the latest European Union countries’ statistics the incidence of HC cancer is about 8,29 per 100000 accidents, cholangiocellular (CC cancer – 0,9-1,3 per 100 thousand of population per year[10,14]. Hepatitis B virus (HBV is the major etiologic factor for the development of HCC [18]. People chronically infected with HBV are 20 times more likely to develop liver cancer than uninfected people [1,22,28]. Many studies have shown the association between Hepatitis B virus (HBV and hepatitis C virus (HCV infections and the development of cholangiocarcinoma (CCA [4,6,9,11,12]. At the same time, the expression features of HBsAg, HBcAg in HCC and CCA have not been studied clearly yet. Aim of investigation: to study the expression features of hepatitis B antigens in tumor tissue from patients with hepatocellular carcinoma and cholangiocarcinoma. Materials and methods. The complex pathomorphological research was performed using liver biopsies of 87 patients aged from 33 up to 83 years, where 50 (57,47% of them had HCC carcinoma and 37 (42,53% had cholangiocellular cancer. 15 patients among examined 87 ones were ill with chronic viral hepatitis (11 were ill with HCV, 3 – HBV B, 1 – HBV + HCV before, 72 cancer patients, corresponding to the clinical data, never had this one in their past medical history. The localization of hepatitis B surface antigen (HBsAg and core antigen (HBcAg was investigated by an indirect immunoperoxidase method in formalin-fixed, paraffin-embedded liver specimens obtained from 50 (57,47% patients with hepatocellular carcinoma and 37 (42,53% patients with cholangiocarcinoma. using antibodies Rb a-Hu Primary Hepatitis B Virus Core Antigen (HBcAg and Mo a-Hu Primary Hepatitis B Virus Surface Antigen (HBsAg, Сlone 3E7, and visualization system DAKO EnVision+ with diaminobenzidine. Liver

Magnitude of Alloresponses to MHC Class I/II Expressing Human Cardiac Myocytes is Limited by their Intrinsic Ability to Process and Present Antigenic Peptides

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Aftab A. Ansari

2003-01-01

Full Text Available In this investigation we have explored the relationship between the weak allogenicity of cardiac myocytes and their capacity to present allo-antigens by examining the ability of a human cardiac myocyte cell line (W-1 to process and present nominal antigens. W-1 cells (HLA-A*0201 and HLA-DR β1*0301 pulsed with the influenza A matrix 1 (58-66 peptide (M1 were able to serve as targets for the HLA-A*0201 restricted CTL line PG, specific for M1-peptide. However, PG-CTLs were unable to lyse W-1 target cells infected with a recombinant vaccinia virus expressing the M1 protein (M1-VAC. Pretreatment of these M1-VAC targets with IFN-γ partially restored their ability to process and present the M1 peptide. However, parallel studies demonstrated that IFN-γ pretreated W-1's could not process tetanus toxin (TT or present the TT(830-843 peptide to HLA-DR3 restricted TT-primed T cells. Semi-quantitative RT-PCR measurements revealed significantly lower constitutive levels of expression for MHC class I, TAP-1/2, and LMP-2/7 genes in W-1s that could be elevated by pretreatment with IFN-γ to values equal to or greater than those expressed in EBV-PBLs. However, mRNA levels for the genes encoding MHC class II, Ii, CIITA, and DMA/B were markedly lower in both untreated and IFN-γ pretreated W-1s relative to EBV-PBLs. Furthermore, pulse-chase analysis of the corresponding genes revealed significantly lower protein levels and longer half-life expression in W-1s relative to EBV-PBLs. These results suggest that weak allogenicity of cardiac myocytes may be governed by their limited expression of MHC genes and gene products critical for antigen processing and presentation.

Pur-Alpha Induces JCV Gene Expression and Viral Replication by Suppressing SRSF1 in Glial Cells.

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Ilker Kudret Sariyer

Full Text Available PML is a rare and fatal demyelinating disease of the CNS caused by the human polyomavirus, JC virus (JCV, which occurs in AIDS patients and those on immunosuppressive monoclonal antibody therapies (mAbs. We sought to identify mechanisms that could stimulate reactivation of JCV in a cell culture model system and targeted pathways which could affect early gene transcription and JCV T-antigen production, which are key steps of the viral life cycle for blocking reactivation of JCV. Two important regulatory partners we have previously identified for T-antigen include Pur-alpha and SRSF1 (SF2/ASF. SRSF1, an alternative splicing factor, is a potential regulator of JCV whose overexpression in glial cells strongly suppresses viral gene expression and replication. Pur-alpha has been most extensively characterized as a sequence-specific DNA- and RNA-binding protein which directs both viral gene transcription and mRNA translation, and is a potent inducer of the JCV early promoter through binding to T-antigen.Pur-alpha and SRSF1 both act directly as transcriptional regulators of the JCV promoter and here we have observed that Pur-alpha is capable of ameliorating SRSF1-mediated suppression of JCV gene expression and viral replication. Interestingly, Pur-alpha exerted its effect by suppressing SRSF1 at both the protein and mRNA levels in glial cells suggesting this effect can occur independent of T-antigen. Pur-alpha and SRSF1 were both localized to oligodendrocyte inclusion bodies by immunohistochemistry in brain sections from patients with HIV-1 associated PML. Interestingly, inclusion bodies were typically positive for either Pur-alpha or SRSF1, though some cells appeared to be positive for both proteins.Taken together, these results indicate the presence of an antagonistic interaction between these two proteins in regulating of JCV gene expression and viral replication and suggests that they play an important role during viral reactivation leading to

Antigenic characterisation of yeast-expressed lyssavirus nucleoproteins.

Science.gov (United States)

Kucinskaite, Indre; Juozapaitis, Mindaugas; Serva, Andrius; Zvirbliene, Aurelija; Johnson, Nicholas; Staniulis, Juozas; Fooks, Anthony R; Müller, Thomas; Sasnauskas, Kestutis; Ulrich, Rainer G

2007-12-01

In Europe, three genotypes of the genus Lyssavirus, family Rhabdoviridae, are present, classical rabies virus (RABV, genotype 1), European bat lyssavirus type 1 (EBLV-1, genotype 5) and European bat lyssavirus type 2 (EBLV-2, genotype 6). The entire authentic nucleoprotein (N protein) encoding sequences of RABV (challenge virus standard, CVS, strain), EBLV-1 and EBLV-2 were expressed in yeast Saccharomyces cerevisiae at high level. Purification of recombinant N proteins by caesium chloride gradient centrifugation resulted in yields between 14-17, 25-29 and 18-20 mg/l of induced yeast culture for RABV-CVS, EBLV-1 and EBLV-2, respectively. The purified N proteins were evaluated by negative staining electron microscopy, which revealed the formation of nucleocapsid-like structures. The antigenic conformation of the N proteins was investigated for their reactivity with monoclonal antibodies (mAbs) directed against different lyssaviruses. The reactivity pattern of each mAb was virtually identical between immunofluorescence assay with virus-infected cells, and ELISA and dot blot assay using the corresponding recombinant N proteins. These observations lead us to conclude that yeast-expressed lyssavirus N proteins share antigenic properties with naturally expressed virus protein. These recombinant proteins have the potential for use as components of serological assays for lyssaviruses.

Gene expression

International Nuclear Information System (INIS)

Hildebrand, C.E.; Crawford, B.D.; Walters, R.A.; Enger, M.D.

1983-01-01

We prepared probes for isolating functional pieces of the metallothionein locus. The probes enabled a variety of experiments, eventually revealing two mechanisms for metallothionein gene expression, the order of the DNA coding units at the locus, and the location of the gene site in its chromosome. Once the switch regulating metallothionein synthesis was located, it could be joined by recombinant DNA methods to other, unrelated genes, then reintroduced into cells by gene-transfer techniques. The expression of these recombinant genes could then be induced by exposing the cells to Zn 2+ or Cd 2+ . We would thus take advantage of the clearly defined switching properties of the metallothionein gene to manipulate the expression of other, perhaps normally constitutive, genes. Already, despite an incomplete understanding of how the regulatory switch of the metallothionein locus operates, such experiments have been performed successfully

Cloning an expressed gene shared by the human sex chromosomes

International Nuclear Information System (INIS)

Darling, S.M.; Banting, G.S.; Pym, B.; Wolfe, J.; Goodfellow, P.N.

1986-01-01

The existence of genes shared by mammalian sex chromosomes has been predicted on both evolutionary and functional grounds. However, the only experimental evidence for such genes in humans is the cell-surface antigen encoded by loci on the X and Y chromosomes (MIC2X and MIC2Y, respectively), which is recognized by the monoclonal antibody 12E7. Using the bacteriophage λgt11 expression system in Escherichia coli and immunoscreening techniques, the authors have isolated a cDNA clone whose primary product is recognized by 12E7. Southern blot analysis using somatic cell hybrids containing only the human X or Y chromosomes shows that the sequences reacting with the cDNA clone are localized to the sex chromosomes. In addition, the clone hybridizes to DNAs isolated from mouse cells that have been transfected with human DNA and selected for 12E7 expression on the fluorescence-activated cell sorter. The authors conclude that the cDNA clone encodes the 12E7 antigen, which is the primary product of the MIC2 loci. The clone was used to explore sequence homology between MIC2X and MIC2Y; these loci are closely related, if not identical

Duffy blood group antigens: structure, serological properties and function

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Ewa Łukasik

2016-03-01

Full Text Available Duffy (Fy blood group antigens are located on seven-transmembrane glycoprotein expressed on erythrocytes and endothelial cells, which acts as atypical chemokine receptor (ACKR1 and malarial receptor. The biological role of the Duffy glycoprotein has not been explained yet. It is suggested that Duffy protein modulate the intensity of the inflammatory response. The Duffy blood group system consists of two major antigens, Fya and Fyb, encoded by two codominant alleles designated FY*A and FY*B which differ by a single nucleotide polymorphism (SNP at position 125G>A of the FY gene that results in Gly42Asp amino acid change in the Fya and Fyb antigens, respectively. The presence of antigen Fya and/or Fyb on the erythrocytes determine three Duffy-positive phenotypes: Fy(a+b-, Fy(a-b+ and Fy(a+b+, identified in Caucasian population. The Duffy-negative phenotype Fy(a-b-, frequent in Africans, but very rare in Caucasians, is defined by the homozygous state of FY*B-33 alleles. The FY*B-33 allele is associated with a SNP -33T>C in the promoter region of the FY gene, which suppresses erythroid expression of this gene without affecting its expression in other tissues. The FY*X allele, found in Caucasians, is correlated with weak expression of Fyb antigen. Fyx antigen differs from the native Fyb by the Arg89Cys and Ala100Thr amino acid substitutions due to SNPs: 265C>T and 298G>A in FY*B allele. The frequency of the FY alleles shows marked geographic disparities, the FY*B-33 allele is predominant in Africans, the FY*B in Caucasians, while the FY*A allele is dominant in Asians and it is the most prevalent allele globally.

Morphological correlates of genital HPV infection: Viral replication, transcription and gene expression

International Nuclear Information System (INIS)

Crum, C.P.; Friedman, D.; Nuovo, G.; Silverstein, S.J.

1987-01-01

Current studies indicate a strong correlation between specific morphological changes and the presence of certain HPV strains in precancerous squamous epithelium of the cervix, vulva and vagina. HPV type 16 is the most commonly detected HPV type in cervical lesions in our experience, and 85% of these lesions exhibit some morphological features associated with aneuploid epithelium (CIN). However, over 50% of these lesions containing HPV 16 DNA exhibit, in addition, foci of epithelium indistinguishable from condyloma, although in our experience, only one HPV type(16) is detected in the majority of these lesions. DNA-DNA in situ hybridization analysis of these lesions containing HPV 16 DNA has demonstrated nucleic acids in areas resembling both condyloma and CIN, with the greatest concentration in mature cells containing cytoplasmic maturation. Ten percent of lesions containing HPV 16 produce detectable capsid antigens, and we have confirmed the presence of these antigens in the same areas which hybridize in-situ for HPV DNA. Recent studies using biotin and S-35 labeled RNa probes constructed in GEM-1 vectors indicate that early HPV genes are expressed primarily in the upper (more mature) regions of the neoplastic epithelium. Thus maturation appears to exert a positive influence on a variety of HPV functions in neoplastic epithelium, including DNA replication, early and late gene expression. It is possible that patterns of gene expression may vary between lesions associated with different HPV types or different morphologies. This possibility is being explored

Fiscal 2000 pioneering research report on the basic technology for novel DNA drug creation using anti-gene engineering; 2000 nendo anti gene kogaku ni yoru shinki DNA drug soshutsu kiban gijutsu chosa kenkyu hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-03-01

Research is conducted concerning the possibility of anti-gene engineering basic to the application of DNA (deoxyribonucleic acid) drugs capable of serving as functional DNAs to the control of the expression of industrially useful substance producing genes or of anomalous genes and concerning the possibility of novel industry creation on the strength of the said engineering. The specific research items are described below. Technical seeds are investigated relating to the tissue- and cell-specific drug delivery system for the expression of the molecular device function of the DNA drug. Concerning molecular target technologies such as the anti-sense method, possibilities are studied of utilizing the currently available technical seeds for the eventual creation of novel industries. Concerning novel designing methods utilizing genome information such as SNPs (single nucleotide polymorphisms), investigations are conducted to determine if they would help novel technology development and novel material development. The domestic state is surveyed in relation to DNA drugs, and possibilities are investigated of novel substance production and novel medicine creation with the aid of anti-gene engineering. (NEDO)

Augmentation of antigen-specific immune responses using DNA-fusogenic liposome vaccine

International Nuclear Information System (INIS)

Yoshikawa, Tomoaki; Imazu, Susumu; Gao Jianqing; Hayashi, Kazuyuki; Tsuda, Yasuhiro; Shimokawa, Mariko; Sugita, Toshiki; Niwa, Takako; Oda, Atushi; Akashi, Mitsuru; Tsutsumi, Yasuo; Mayumi, Tadanori; Nakagawa, Shinsaku

2004-01-01

In an attempt to enhance the immunological efficacy of genetic immunization, we investigated a new biological means for delivering antigen gene directly to the cytoplasm via membrane fusion. In this context, we investigated fusogenic liposome (FL) encapsulating DNA as a possible genetic immunization vehicle. RT-PCR analysis indicated that a FL could introduce and express encapsulating OVA gene efficiently and rapidly in vitro. Consistent with this observation, an in vitro assay showed that FL-mediated antigen-gene delivery can induce potent presentation of antigen via the MHC class I-dependent pathway. Accordingly, immunization with FL containing the OVA-gene induced potent OVA-specific Th1 and Th2 cytokine production. Additionally, OVA-specific CTL responses and antibody production were also observed in systemic compartments including the spleen, upon immunization with the OVA-gene encapsulating FL. These findings suggest that FL is an effective genetic immunization carrier system for the stimulation of antigen-specific immune responses against its encoding antigen

Neighboring Genes Show Correlated Evolution in Gene Expression

Science.gov (United States)

Ghanbarian, Avazeh T.; Hurst, Laurence D.

2015-01-01

When considering the evolution of a gene’s expression profile, we commonly assume that this is unaffected by its genomic neighborhood. This is, however, in contrast to what we know about the lack of autonomy between neighboring genes in gene expression profiles in extant taxa. Indeed, in all eukaryotic genomes genes of similar expression-profile tend to cluster, reflecting chromatin level dynamics. Does it follow that if a gene increases expression in a particular lineage then the genomic neighbors will also increase in their expression or is gene expression evolution autonomous? To address this here we consider evolution of human gene expression since the human-chimp common ancestor, allowing for both variation in estimation of current expression level and error in Bayesian estimation of the ancestral state. We find that in all tissues and both sexes, the change in gene expression of a focal gene on average predicts the change in gene expression of neighbors. The effect is highly pronounced in the immediate vicinity (genes increasing their expression in humans tend to avoid nuclear lamina domains and be enriched for the gene activator 5-hydroxymethylcytosine, we conclude that, most probably owing to chromatin level control of gene expression, a change in gene expression of one gene likely affects the expression evolution of neighbors, what we term expression piggybacking, an analog of hitchhiking. PMID:25743543

Human Tregs Made Antigen Specific by Gene Modification: The Power to Treat Autoimmunity and Antidrug Antibodies with Precision

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Patrick R. Adair

2017-09-01

Full Text Available Human regulatory CD4+ T cells (Tregs are potent immunosuppressive lymphocytes responsible for immune tolerance and homeostasis. Since the seminal reports identifying Tregs, vast research has been channeled into understanding their genesis, signature molecular markers, mechanisms of suppression, and role in disease. This research has opened the doors for Tregs as a potential therapeutic for diseases and disorders such as multiple sclerosis, type I diabetes, transplantation, and immune responses to protein therapeutics, like factor VIII. Seminal clinical trials have used polyclonal Tregs, but the frequency of antigen-specific Tregs among polyclonal populations is low, and polyclonal Tregs may risk non-specific immunosuppression. Antigen-specific Treg therapy, which uses genetically modified Tregs expressing receptors specific for target antigens, greatly mitigates this risk. Building on the principles of T-cell receptor cloning, chimeric antigen receptors (CARs, and a novel CAR derivative, called B-cell antibody receptors, our lab has developed different types of antigen-specific Tregs. This review discusses the current research and optimization of gene-modified antigen-specific human Tregs in our lab in several disease models. The preparations and considerations for clinical use of such Tregs also are discussed.

Antimetastatic gene expression profiles mediated by retinoic acid receptor beta 2 in MDA-MB-435 breast cancer cells

International Nuclear Information System (INIS)

Wallden, Brett; Emond, Mary; Swift, Mari E; Disis, Mary L; Swisshelm, Karen

2005-01-01

The retinoic acid receptor beta 2 (RARβ2) gene modulates proliferation and survival of cultured human breast cancer cells. Previously we showed that ectopic expression of RARβ2 in a mouse xenograft model prevented metastasis, even in the absence of the ligand, all-trans retinoic acid. We investigated both cultured cells and xenograft tumors in order to delineate the gene expression profiles responsible for an antimetastatic phenotype. RNA from MDA-MB-435 human breast cancer cells transduced with RARβ2 or empty retroviral vector (LXSN) was analyzed using Agilent Human 1A Oligo microarrays. The one hundred probes with the greatest differential intensity (p < 0.004, jointly) were determined by selecting the top median log ratios from eight-paired microarrays. Validation of differences in expression was done using Northern blot analysis and quantitative RT-PCR (qRT-PCR). We determined expression of selected genes in xenograft tumors. RARβ2 cells exhibit gene profiles with overrepresentation of genes from Xq28 (p = 2 × 10 -8 ), a cytogenetic region that contains a large portion of the cancer/testis antigen gene family. Other functions or factors impacted by the presence of exogenous RARβ2 include mediators of the immune response and transcriptional regulatory mechanisms. Thirteen of fifteen (87%) of the genes evaluated in xenograft tumors were consistent with differences we found in the cell cultures (p = 0.007). Antimetastatic RARβ2 signalling, direct or indirect, results in an elevation of expression for genes such as tumor-cell antigens (CTAG1 and CTAG2), those involved in innate immune response (e.g., RIG-I/DDX58), and tumor suppressor functions (e.g., TYRP1). Genes whose expression is diminished by RARβ2 signalling include cell adhesion functions (e.g, CD164) nutritional or metabolic processes (e.g., FABP6), and the transcription factor, JUN

Cloning and Expressing Recombinant Protective Antigen Domains of B. anthracis

Science.gov (United States)

2011-09-01

future predictive modeling toolkits. 1 1. Introduction The use of Bacillus anthracis as a bio - weapon in the United States in 2001 affirmed the need...for improved sensing and detection of biological weapons of mass destruction (WMD). Protective Antigen (PA) protein of Bacillus anthracis is the...Cloning and Expressing Recombinant Protective Antigen Domains of B. anthracis by Deborah A. Sarkes, Joshua M. Kogot, Irene Val-Addo

Gene Expression Commons: an open platform for absolute gene expression profiling.

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Jun Seita

Full Text Available Gene expression profiling using microarrays has been limited to comparisons of gene expression between small numbers of samples within individual experiments. However, the unknown and variable sensitivities of each probeset have rendered the absolute expression of any given gene nearly impossible to estimate. We have overcome this limitation by using a very large number (>10,000 of varied microarray data as a common reference, so that statistical attributes of each probeset, such as the dynamic range and threshold between low and high expression, can be reliably discovered through meta-analysis. This strategy is implemented in a web-based platform named "Gene Expression Commons" (https://gexc.stanford.edu/ which contains data of 39 distinct highly purified mouse hematopoietic stem/progenitor/differentiated cell populations covering almost the entire hematopoietic system. Since the Gene Expression Commons is designed as an open platform, investigators can explore the expression level of any gene, search by expression patterns of interest, submit their own microarray data, and design their own working models representing biological relationship among samples.

Multiple sclerosis risk variant HLA-DRB1*1501 associates with high expression of DRB1 gene in different human populations.

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Antonio Alcina

Full Text Available The human leukocyte antigen (HLA DRB1*1501 has been consistently associated with multiple sclerosis (MS in nearly all populations tested. This points to a specific antigen presentation as the pathogenic mechanism though this does not fully explain the disease association. The identification of expression quantitative trait loci (eQTL for genes in the HLA locus poses the question of the role of gene expression in MS susceptibility. We analyzed the eQTLs in the HLA region with respect to MS-associated HLA-variants obtained from genome-wide association studies (GWAS. We found that the Tag of DRB1*1501, rs3135388 A allele, correlated with high expression of DRB1, DRB5 and DQB1 genes in a Caucasian population. In quantitative terms, the MS-risk AA genotype carriers of rs3135388 were associated with 15.7-, 5.2- and 8.3-fold higher expression of DQB1, DRB5 and DRB1, respectively, than the non-risk GG carriers. The haplotype analysis of expression-associated variants in a Spanish MS cohort revealed that high expression of DRB1 and DQB1 alone did not contribute to the disease. However, in Caucasian, Asian and African American populations, the DRB1*1501 allele was always highly expressed. In other immune related diseases such as type 1 diabetes, inflammatory bowel disease, ulcerative colitis, asthma and IgA deficiency, the best GWAS-associated HLA SNPs were also eQTLs for different HLA Class II genes. Our data suggest that the DR/DQ expression levels, together with specific structural properties of alleles, seem to be the causal effect in MS and in other immunopathologies rather than specific antigen presentation alone.

Biosynthetic basis of incompatible histo-blood group A antigen expression

DEFF Research Database (Denmark)

David, L; Leitao, D; Sobrinho-Simoes, M

1993-01-01

The expression of incompatible A carbohydrate antigens in some adenocarcinomas may provide an explanation for the generally observed lower incidence of adenocarcinoma among types O and B versus type A individuals. The chemistry and genetic basis of incompatible A expression is largely unknown. He...

[Reconstruction of Leptospira interrogans lipL21 gene and characteristics of its expression product].

Science.gov (United States)

Luo, Dong-jiao; Hu, Ye; Dennin, R H; Yan, Jie

2007-09-01

To reconstruct the nucleotide sequence of Leptospira interrogans lipL21 gene for increasing the output of prokaryotic expression and to understand the changes on immunogenicity of the expression products before and after reconstruction, and to determine the position of envelope lipoprotein LipL21 on the surface of leptospiral body. According to the preferred codons of E.coli, the nucleotide sequence of lipL21 gene was designed and synthesized, and then its prokaryotic expression system was constructed. By using SDS-PAGE plus BioRad agarose image analysor, the expression level changes of lipL21 genes before and after reconstruction were measured. A Western blot assay using rabbit anti-TR/Patoc I serum as the first antibody was performed to identify the immunoreactivity of the two target recombinant proteins rLipL21s before and after reconstruction. The changes of cross agglutination titers of antisera against two rLipL21s before and after reconstruction to the different leptospiral serogroups were demonstrated using microscope agglutination test (MAT). Immuno-electronmicroscopy was applied to confirm the location of LipL21s. The expression outputs of original and reconstructed lipL21 genes were 8.5 % and 46.5 % of the total bacterial proteins, respectively. Both the two rLipL21s could take place immune conjugation reaction with TR/Patoc I antiserum. After immunization with each of the two rLipL21s in rabbits, the animals could produce specific antibody. Similar MAT titers with 1:80 - 1:320 of the two antisera against rLipL21s were present. LipL21 was confirmed to locate on the surface of leptospiral envelope. LipL21 is a superficial antigen of Leptospira interrogans. The expression output of the reconstructed lipL21 gene is remarkably increased. The expression rLipL21 maintains fine antigenicity and immunoreactivity and its antibody still shows an extensive cross immunoagglutination activity. The high expression of the reconstructed lipL21 gene will offer a

Expression of tomato yellow leaf curl virus coat protein using baculovirus expression system and evaluation of its utility as a viral antigen.

Science.gov (United States)

Elgaied, Lamiaa; Salem, Reda; Elmenofy, Wael

2017-08-01

DNA encoding the coat protein (CP) of an Egyptian isolate of tomato yellow leaf curl virus (TYLCV) was inserted into the genome of Autographa californica nucleopolyhedrovirus (AcNPV) under the control of polyhedrin promoter. The generated recombinant baculovirus construct harboring the coat protein gene was characterized using PCR analysis. The recombinant coat protein expressed in infected insect cells was used as a coating antigen in an indirect Enzyme-linked immunosorbent assay (ELISA) and dot blot to test its utility for the detection of antibody generated against TYLCV virus particles. The results of ELISA and dot blot showed that the TYLCV-antibodies reacted positively with extracts of infected cells using the recombinant virus as a coating antigen with strong signals as well as the TYLCV infected tomato and beat plant extracts as positive samples. Scanning electron microscope examination showed that the expressed TYLCV coat protein was self-assembled into virus-like particles (VLPs) similar in size and morphology to TYLCV virus particles. These results concluded that, the expressed coat protein of TYLCV using baculovirus vector system is a reliable candidate for generation of anti-CP antibody for inexpensive detection of TYLCV-infected plants using indirect CP-ELISA or dot blot with high specificity.

General and family-specific gene expression responses to viral hemorrhagic septicaemia virus infection in rainbow trout (Oncorhynchus mykiss)

DEFF Research Database (Denmark)

Jørgensen, H. B. H.; Sørensen, P.; Cooper, G. A.

2011-01-01

challenge) and a relatively high susceptibility (18% survival following challenge) trout family that were both split into a group exposed to virus and a non-exposed control group. In total, 939 genes were differentially expressed between infected and non-infected fish (FDR p = 0.05). Five groups of Gene...... Ontology categories were involved in immune-related processes and over-represented in infected fish: (i) stress and defense response, (ii) NFkappaB signal transduction, (iii) response to non-self, (iv) antigen processing and presentation, and (v) proteasome complexes. The first four categories were also...... over-represented among the 642 differentially expressed genes in the low-susceptibility trout family but not among the 556 differentially expressed genes in the high-susceptibility trout family. Expression profiles for most immune genes discussed showed increased transcription from day 3 post...

Axotomy induces MHC class I antigen expression on rat nerve cells

DEFF Research Database (Denmark)

Maehlen, J; Schröder, H D; Klareskog, L

1988-01-01

Immunomorphological staining demonstrates that class I major histocompatibility complex (MHC)-coded antigen expression can be selectively induced on otherwise class I-negative rat nerve cells by peripheral axotomy. Induction of class I as well as class II antigen expression was simultaneously seen...... on non-neural cells in the immediate vicinity of the injured nerve cells. As nerve regeneration after axotomy includes growth of new nerve cell processes and formation of new nerve cell contacts, the present findings raise the question of a role for MHC-coded molecules in cell-cell interactions during...... nerve cell growth....

Alteration of the gene expression profile of T-cell receptor αβ-modified T-cells with diffuse large B-cell lymphoma specificity.

Science.gov (United States)

Zha, Xianfeng; Yin, Qingsong; Tan, Huo; Wang, Chunyan; Chen, Shaohua; Yang, Lijian; Li, Bo; Wu, Xiuli; Li, Yangqiu

2013-05-01

Antigen-specific, T-cell receptor (TCR)-modified cytotoxic T lymphocytes (CTLs) that target tumors are an attractive strategy for specific adoptive immunotherapy. Little is known about whether there are any alterations in the gene expression profile after TCR gene transduction in T cells. We constructed TCR gene-redirected CTLs with specificity for diffuse large B-cell lymphoma (DLBCL)-associated antigens to elucidate the gene expression profiles of TCR gene-redirected T-cells, and we further analyzed the gene expression profile pattern of these redirected T-cells by Affymetrix microarrays. The resulting data were analyzed using Bioconductor software, a two-fold cut-off expression change was applied together with anti-correlation of the profile ratios to render the microarray analysis set. The fold change of all genes was calculated by comparing the three TCR gene-modified T-cells and a negative control counterpart. The gene pathways were analyzed using Bioconductor and Kyoto Encyclopedia of Genes and Genomes. Identical genes whose fold change was greater than or equal to 2.0 in all three TCR gene-redirected T-cell groups in comparison with the negative control were identified as the differentially expressed genes. The differentially expressed genes were comprised of 33 up-regulated genes and 1 down-regulated gene including JUNB, FOS, TNF, INF-γ, DUSP2, IL-1B, CXCL1, CXCL2, CXCL9, CCL2, CCL4, and CCL8. These genes are mainly involved in the TCR signaling, mitogen-activated protein kinase signaling, and cytokine-cytokine receptor interaction pathways. In conclusion, we characterized the gene expression profile of DLBCL-specific TCR gene-redirected T-cells. The changes corresponded to an up-regulation in the differentiation and proliferation of the T-cells. These data may help to explain some of the characteristics of the redirected T-cells.

Prediction of graft-versus-host disease in humans by donor gene-expression profiling.

Directory of Open Access Journals (Sweden)

Chantal Baron

2007-01-01

Full Text Available BACKGROUND: Graft-versus-host disease (GVHD results from recognition of host antigens by donor T cells following allogeneic hematopoietic cell transplantation (AHCT. Notably, histoincompatibility between donor and recipient is necessary but not sufficient to elicit GVHD. Therefore, we tested the hypothesis that some donors may be "stronger alloresponders" than others, and consequently more likely to elicit GVHD. METHODS AND FINDINGS: To this end, we measured the gene-expression profiles of CD4(+ and CD8(+ T cells from 50 AHCT donors with microarrays. We report that pre-AHCT gene-expression profiling segregates donors whose recipient suffered from GVHD or not. Using quantitative PCR, established statistical tests, and analysis of multiple independent training-test datasets, we found that for chronic GVHD the "dangerous donor" trait (occurrence of GVHD in the recipient is under polygenic control and is shaped by the activity of genes that regulate transforming growth factor-beta signaling and cell proliferation. CONCLUSIONS: These findings strongly suggest that the donor gene-expression profile has a dominant influence on the occurrence of GVHD in the recipient. The ability to discriminate strong and weak alloresponders using gene-expression profiling could pave the way to personalized transplantation medicine.

Differential expression of the Escherichia coli autoaggregation factor antigen 43

DEFF Research Database (Denmark)

Schembri, Mark; Hjerrild, Louise; Gjermansen, Morten

2003-01-01

Antigen 43 (Ag43) is a self-recognizing surface adhesin found in most Escherichia coli strains. Due to its excellent cell-to-cell aggregation characteristics, Ag43 expression confers clumping and fluffing of cells and promotes biofilm formation. Ag43 expression is repressed by the cellular redox...

Expression of the Native Cholera Toxin B Subunit Gene and Assembly as Functional Oligomers in Transgenic Tobacco Chloroplasts

Science.gov (United States)

Daniell, Henry; Lee, Seung-Bum; Panchal, Tanvi; Wiebe, Peter O.

2012-01-01

The B subunits of enterotoxigenic Escherichia coli (LTB) and cholera toxin of Vibrio cholerae (CTB) are candidate vaccine antigens. Integration of an unmodified CTB-coding sequence into chloroplast genomes (up to 10,000 copies per cell), resulted in the accumulation of up to 4.1% of total soluble tobacco leaf protein as functional oligomers (410-fold higher expression levels than that of the unmodified LTB gene expressed via the nuclear genome). However, expresssion levels reported are an underestimation of actual accumulation of CTB in transgenic chloroplasts, due to aggregation of the oligomeric forms in unboiled samples similar to the aggregation observed for purified bacterial antigen. PCR and Southern blot analyses confirmed stable integration of the CTB gene into the chloroplast genome. Western blot analysis showed that the chloroplast-synthesized CTB assembled into oligomers and were antigenically identical with purified native CTB. Also, binding assays confirmed that chloroplast- synthesized CTB binds to the intestinal membrane GM1-ganglioside receptor, indicating correct folding and disulfide bond formation of CTB pentamers within transgenic chloroplasts. In contrast to stunted nuclear transgenic plants, chloroplast transgenic plants were morphologically indistinguishable from untransformed plants, when CTB was constitutively expressed in chloroplasts. Introduced genes were inherited stably in subsequent generations, as confirmed by PCR and Southern blot analyses. Increased production of an efficient transmucosal carrier molecule and delivery system, like CTB, in transgenic chloroplasts makes plant-based oral vaccines and fusion proteins with CTB needing oral administration commercially feasible. Successful expression of foreign genes in transgenic chromoplasts and availability of marker-free chloroplast transformation techniques augurs well for development of vaccines in edible parts of transgenic plants. Furthermore, since the quaternary structure of

Structure and expression of the human and mouse T4 genes

International Nuclear Information System (INIS)

Maddon, P.J.; Molineaux, S.M.; Maddon, D.F.; Zimmerman, K.A.; Godfrey, M.; Alt, F.W.; Chess, L.; Axel, R.

1987-01-01

The T4 molecule may serve as a T-cell receptor recognizing molecules on the surface of specific target cells and also serves as the receptor for the human immunodeficiency virus. To define the mechanisms of interaction of T4 with the surface of antigen-presenting cells as well as with human immunodeficiency virus, the authors have further analyzed the sequence, structure, and expression of the human and mouse T4 genes. T4 consists of an extracellular segment comprised of a leader sequence followed by four tandem variable-joining (VJ)-like domains, a transmembrane domain, and A cytoplasmic segment. The structural domains of the T4 protein deduced from amino acid sequence are precisely reflected in the intron-exon organization of the gene. Analysis of the expression of the T4 gene indicates that T4 RNA is expressed not only in T lymphocytes, but in B cells, macrophages, and granulocytes. T4 is also expressed in a developmentally regulated manner in specific regions of the brain. It is, therefore, possible that T4 plays a more general role in mediating cell recognition events that are not restricted to the cellular immune response

Effect of radiation on the expression of tumor-associated antigens of human lung adenocarcinoma cells. Immunological study using monoclonal antibodies

Energy Technology Data Exchange (ETDEWEB)

Hareyama, Masato

1988-12-01

We studied the effects of irradiation on the expression of a tumor-associated antigen (YH206 antigen) of cultured human lung adenocarcinoma A549 cells by using enzyme-linked immunosorbent assay (ELISA) and flow cytometry. YH206 antigen is preferentially expressed on adenocarcinoma cells. Irradiation of A549 cells remarkably increased the expression of YH206 antigen on the cell surface and the level of the antigen in the culture supernatant as well as in the cell lysate, whereas it significantly affected the expression of HLA (MHC-class I) antigen on the same cells. The expression of HLA antigen on the cell was also increased after treatment of the cells with interferon-..gamma... In an additional experiment, cells were stained simultaneously for surface antigens (fluorescein coupled antibodies) and for DNA content (propidium iodide), and then dual parameter measurements were performed by flow cytometry to analyse the relationship between antigen levels and the cell cycle. YH206 antigen and HLA antigen increased more in the S and G/sub 2//M phases of the cell cycle than in G/sub 0//G/sub 1/. The expression of YH206 antigen was enhanced in the S and G/sub 2//M phases by irradiation, whereas the expression of HLA antigen was enhanced in each phase of the cell cycle with irradiation or IFN. These results suggest that irradiation plays a key role in the change of the expression of certain tumor-associated antigens.

Gene expression study and pathway analysis of histological subtypes of intestinal metaplasia that progress to gastric cancer.

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Osmel Companioni

Full Text Available Intestinal metaplasia (IM is a precursor lesion that precedes gastric cancer (GC. There are two IM histological subtypes, complete (CIM and incomplete (IIM, the latter having higher progression rates to GC. This study was aimed at analysing gene expression and molecular processes involved in the progression from normal mucosa to IM, and also from IM subtypes to GC.We used expression data to compare the transcriptome of healthy gastric mucosa to that of IM not progressing to GC, and the transcriptome of IM subtypes that had progressed to GC to those that did not progress. Some deregulated genes were validated and pathway analyses were performed.Comparison of IM subtypes that had progressed to GC with those that did not progress showed smaller differences in the expression profiles than the comparison of IM that did not progress with healthy mucosa. New transcripts identified in IM not progressing to GC included TRIM, TMEM, homeobox and transporter genes and SNORD116. Comparison to normal mucosa identified non tumoral Warburg effect and melatonin degradation as previously unreported processes involved in IM. Overexpressed antigen processing is common to both IM-subtypes progressing to GC, but IIM showed more over-expressed oncogenic genes and molecular processes than CIM.There are greater differences in gene expression and molecular processes involved in the progression from normal healthy mucosa to IM than from IM to gastric cancer. While antigen processing is common in both IM-subtypes progressing to GC, more oncogenic processes are observed in the progression of IIM.

Cloning of synthetic gene including antigens against Urinary Tract Infections in pET28a+ vector

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Zohreh Haghri

2017-12-01

Full Text Available There are many different bacterial infections in the world that patients are suffering from and research teams are trying to find suitable ways to prevent and treat them. Urinary Tract Infections (UTIs are most important infections in the world , and they are more common among women because vaginal cavity is near to urethral opening. The aim of this study is cloning of synthetic gene include antigens against UTIs in pET28a+ vector. Antibiotic resistant has been increasing because of antibiotic overuse recently, so It shows the necessity of developing a vaccine against these infections. There for, it will be imperative to develop a vaccine instead of antibiotics. This infection causes by many organisms, most important of which are Uropathogenic Escherichia coli (UPEC, Proteus mirabilis and Klebsiella pneumoniae Uropathogenic Escherichia .coli is the most important microorganism that causes these infections more than other bacteria, so in developing a vaccine it is the most important one, that have to be considered. The synthetic Gene which was designed against these three bacteria including antigens which are important and common to cause these infections. This gene has involved 1293bp. It was ordered to Gene Ray Biotechnology. Primers were designed by Gene Runner. Gene and pET28a+ vector was checked by SnappGene. Synthetic gene was multiplied by PCR and cloned in pET28a+ vector. Construct was transformed into E. coli TOP10.The clone was confirmed by PCR, Digestion. This data indicates that this gene can be expressed and it might be a vaccine candidate to protect people from these infections in the future.

Gene Expression Correlation for Cancer Diagnosis: A Pilot Study

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Binbing Ling

2014-01-01

Full Text Available Poor prognosis for late-stage, high-grade, and recurrent cancers has been motivating cancer researchers to search for more efficient biomarkers to identify the onset of cancer. Recent advances in constructing and dynamically analyzing biomolecular networks for different types of cancer have provided a promising novel strategy to detect tumorigenesis and metastasis. The observation of different biomolecular networks associated with normal and cancerous states led us to hypothesize that correlations for gene expressions could serve as valid indicators of early cancer development. In this pilot study, we tested our hypothesis by examining whether the mRNA expressions of three randomly selected cancer-related genes PIK3C3, PIM3, and PTEN were correlated during cancer progression and the correlation coefficients could be used for cancer diagnosis. Strong correlations (0.68≤r≤1.0 were observed between PIK3C3 and PIM3 in breast cancer, between PIK3C3 and PTEN in breast and ovary cancers, and between PIM3 and PTEN in breast, kidney, liver, and thyroid cancers during disease progression, implicating that the correlations for cancer network gene expressions could serve as a supplement to current clinical biomarkers, such as cancer antigens, for early cancer diagnosis.

Gene expression profile and immunological evaluation of unique hypothetical unknown proteins of Mycobacterium leprae by using quantitative real-time PCR.

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Kim, Hee Jin; Prithiviraj, Kalyani; Groathouse, Nathan; Brennan, Patrick J; Spencer, John S

2013-02-01

The cell-mediated immunity (CMI)-based in vitro gamma interferon release assay (IGRA) of Mycobacterium leprae-specific antigens has potential as a promising diagnostic means to detect those individuals in the early stages of M. leprae infection. Diagnosis of leprosy is a major obstacle toward ultimate disease control and has been compromised in the past by the lack of specific markers. Comparative bioinformatic analysis among mycobacterial genomes identified potential M. leprae-specific proteins called "hypothetical unknowns." Due to massive gene decay and the prevalence of pseudogenes, it is unclear whether any of these proteins are expressed or are immunologically relevant. In this study, we performed cDNA-based quantitative real-time PCR to investigate the expression status of 131 putative open reading frames (ORFs) encoding hypothetical unknowns. Twenty-six of the M. leprae-specific antigen candidates showed significant levels of gene expression compared to that of ESAT-6 (ML0049), which is an important T cell antigen of low abundance in M. leprae. Fifteen of 26 selected antigen candidates were expressed and purified in Escherichia coli. The seroreactivity to these proteins of pooled sera from lepromatous leprosy patients and cavitary tuberculosis patients revealed that 9 of 15 recombinant hypothetical unknowns elicited M. leprae-specific immune responses. These nine proteins may be good diagnostic reagents to improve both the sensitivity and specificity of detection of individuals with asymptomatic leprosy.

Susceptibility to experimental biliary atresia linked to different hepatic gene expression profiles in two mouse strains.

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Leonhardt, Johannes; Kuebler, Joachim F; Turowski, Carmen; Tschernig, Thomas; Geffers, Robert; Petersen, Claus

2010-02-01

To compare hepatic gene expression during the development of experimental biliary atresia (BA) in two different mouse strains. Balb/c mice and C57Black/6 (Black/6) mice were infected with rhesus rotavirus (RRV) postpartum, clinical signs of BA and survival were noted. Liver sections were assessed for cluster of differentiation antigen (CD) 3, CD4 and CD8 expression, and the hepatic virus load was determined. Second, mice of both strains were sacrificed three days after infection. Isolated hepatic RNA was subjected to gene expression analysis using Affymetrix Gene Chip MOE 430 2.0. The incidence of BA was significantly lower in Black/6 mice compared to Balb/c mice (13.5% vs. 67%, P < 0.05). The mean virus titers were higher in mice with BA compared to mice without BA. Different gene profiles three days after virus infection were noted, with differential expression of 201 genes, including those regulating apoptosis, nucleic acid binding, transport function and particularly the immune response (chemokine C-C motif ligand 2, toll-like receptor 3, CD antigen 14, chemokine (C-X-C motif) ligands 10 and 11). This correlated with a significant increase of CD4 positive cells only in Balb/c mice with BA compared to healthy mice (13.5 vs. 5.0; P < 0.05). Black/6 mice did not exhibit any significant increase of CD3 or CD4 leukocytes despite cholestasis. The different susceptibility to experimental BA was associated with an increase of CD4 T-cells in the liver of Balb/c mice, which is linked to different gene profiles at the onset of bile duct obstruction.

Imaging gene expression in gene therapy

International Nuclear Information System (INIS)

Wiebe, Leonard I.

1997-01-01

Full text. Gene therapy can be used to introduce new genes, or to supplement the function of indigenous genes. At the present time, however, there is non-invasive test to demonstrate efficacy of the gene transfer and expression processes. It has been postulated that scintigraphic imaging can offer unique information on both the site at which the transferred gene is expressed, and the degree of expression, both of which are critical issue for safety and clinical efficacy. Many current studies are based on 'suicide gene therapy' of cancer. Cells modified to express these genes commit metabolic suicide in the presence of an enzyme encoded by the transferred gene and a specifically-convertible pro drug. Pro drug metabolism can lead to selective metabolic trapping, required for scintigraphy. Herpes simplex virus type-1 thymidine kinase (H S V-1 t k + ) has been use for 'suicide' in vivo tumor gene therapy. It has been proposed that radiolabelled nucleosides can be used as radiopharmaceuticals to detect H S V-1 t k + gene expression where the H S V-1 t k + gene serves a reporter or therapeutic function. Animal gene therapy models have been studied using purine-([ 18 F]F H P G; [ 18 F]-A C V), and pyrimidine- ([ 123 / 131 I]I V R F U; [ 124 / 131I ]) antiviral nucleosides. Principles of gene therapy and gene therapy imaging will be reviewed and experimental data for [ 123 / 131I ]I V R F U imaging with the H S V-1 t k + reporter gene will be presented

Multiple injections of electroporated autologous T cells expressing a chimeric antigen receptor mediate regression of human disseminated tumor.

Science.gov (United States)

Zhao, Yangbing; Moon, Edmund; Carpenito, Carmine; Paulos, Chrystal M; Liu, Xiaojun; Brennan, Andrea L; Chew, Anne; Carroll, Richard G; Scholler, John; Levine, Bruce L; Albelda, Steven M; June, Carl H

2010-11-15

Redirecting T lymphocyte antigen specificity by gene transfer can provide large numbers of tumor-reactive T lymphocytes for adoptive immunotherapy. However, safety concerns associated with viral vector production have limited clinical application of T cells expressing chimeric antigen receptors (CAR). T lymphocytes can be gene modified by RNA electroporation without integration-associated safety concerns. To establish a safe platform for adoptive immunotherapy, we first optimized the vector backbone for RNA in vitro transcription to achieve high-level transgene expression. CAR expression and function of RNA-electroporated T cells could be detected up to a week after electroporation. Multiple injections of RNA CAR-electroporated T cells mediated regression of large vascularized flank mesothelioma tumors in NOD/scid/γc(-/-) mice. Dramatic tumor reduction also occurred when the preexisting intraperitoneal human-derived tumors, which had been growing in vivo for >50 days, were treated by multiple injections of autologous human T cells electroporated with anti-mesothelin CAR mRNA. This is the first report using matched patient tumor and lymphocytes showing that autologous T cells from cancer patients can be engineered to provide an effective therapy for a disseminated tumor in a robust preclinical model. Multiple injections of RNA-engineered T cells are a novel approach for adoptive cell transfer, providing flexible platform for the treatment of cancer that may complement the use of retroviral and lentiviral engineered T cells. This approach may increase the therapeutic index of T cells engineered to express powerful activation domains without the associated safety concerns of integrating viral vectors. Copyright © 2010 AACR.

[Gene deletion and functional analysis of the heptyl glycosyltransferase (waaF) gene in Vibrio parahemolyticus O-antigen cluster].

Science.gov (United States)

Zhao, Feng; Meng, Songsong; Zhou, Deqing

2016-02-04

To construct heptyl glycosyltransferase gene II (waaF) gene deletion mutant of Vibrio parahaemolyticus, and explore the function of the waaF gene in Vibrio parahaemolyticus. The waaF gene deletion mutant was constructed by chitin-based transformation technology using clinical isolates, and then the growth rate, morphology and serotypes were identified. The different sources (O3, O5 and O10) waaF gene complementations were constructed through E. coli S17λpir strains conjugative transferring with Vibrio parahaemolyticus, and the function of the waaF gene was further verified by serotypes. The waaF gene deletion mutant strain was successfully constructed and it grew normally. The growth rate and morphology of mutant were similar with the wild type strains (WT), but the mutant could not occurred agglutination reaction with O antisera. The O3 and O5 sources waaF gene complementations occurred agglutination reaction with O antisera, but the O10 sources waaF gene complementations was not. The waaF gene was related with O-antigen synthesis and it was the key gene of O-antigen synthesis pathway in Vibrio parahaemolyticus. The function of different sources waaF gene were not the same.

Unpolarized release of vaccinia virus and HIV antigen by colchicine treatment enhances intranasal HIV antigen expression and mucosal humoral responses.

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Yan Zhang

Full Text Available The induction of a strong mucosal immune response is essential to building successful HIV vaccines. Highly attenuated recombinant HIV vaccinia virus can be administered mucosally, but even high doses of immunization have been found unable to induce strong mucosal antibody responses. In order to solve this problem, we studied the interactions of recombinant HIV vaccinia virus Tiantan strain (rVTT-gagpol in mucosal epithelial cells (specifically Caco-2 cell layers and in BALB/c mice. We evaluated the impact of this virus on HIV antigen delivery and specific immune responses. The results demonstrated that rVTT-gagpol was able to infect Caco-2 cell layers and both the nasal and lung epithelia in BALB/c mice. The progeny viruses and expressed p24 were released mainly from apical surfaces. In BALB/c mice, the infection was limited to the respiratory system and was not observed in the blood. This showed that polarized distribution limited antigen delivery into the whole body and thus limited immune response. To see if this could be improved upon, we stimulated unpolarized budding of the virus and HIV antigens by treating both Caco-2 cells and BALB/c mice with colchicine. We found that, in BALB/c mice, the degree of infection and antigen expression in the epithelia went up. As a result, specific immune responses increased correspondingly. Together, these data suggest that polarized budding limits antigen delivery and immune responses, but unpolarized distribution can increase antigen expression and delivery and thus enhance specific immune responses. This conclusion can be used to optimize mucosal HIV vaccine strategies.

Expression of Lewisa, Sialyl Lewisa, Lewisx, Sialyl Lewisx, Antigens as Prognostic Factors in Patients with Colorectal Cancer

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Tohru Nakagoe

2000-01-01

Full Text Available BACKGROUND: Altered expression of blood group-related carbohydrate antigens such as sialyl Lewis (Lex antigen in tumours is associated with tumour progression behaviour and subsequent prognosis. However, the prognostic value of the expression of Le-related antigens in colorectal tumours remains unclear.

Determining Physical Mechanisms of Gene Expression Regulation from Single Cell Gene Expression Data

OpenAIRE

Ezer, Daphne; Moignard, Victoria; G?ttgens, Berthold; Adryan, Boris

2016-01-01

Many genes are expressed in bursts, which can contribute to cell-to-cell heterogeneity. It is now possible to measure this heterogeneity with high throughput single cell gene expression assays (single cell qPCR and RNA-seq). These experimental approaches generate gene expression distributions which can be used to estimate the kinetic parameters of gene expression bursting, namely the rate that genes turn on, the rate that genes turn off, and the rate of transcription. We construct a complete ...

Effects of radiation on the expression of antigens on the membranes of human adenocarcinoma cells

International Nuclear Information System (INIS)

Hareyama, Masato; Imai, Kozo; Oouchi, Atsushi; Shidou, Mitsuo; Takahashi, Hiroki; Koshiba, Hirohumi; Yachi, Akira; Morita, Kazuo

1992-01-01

We have investigated the effects of irradiation on the membranes of tumor cells. X-ray irradiation caused remarkable increases in the expression of tumor-associated antigens (YH206, CEA) and c-erbB-2 protein by flow cytometry, whereas IFN had no obvious effect on the expression of tumor-associated antigens and c-erbB-2 protein. On the other hand, the expression of MHC Class I and ICAM-1 antigen on the membrane by flow cytometry was enhanced by both irradiation and IFN. In addition, the irradiated cells, when analyzed using a CEA specific probe, showed remarkable increases in the CEA mRNA compared to IFN-treated cells. It is possible that enhancement of the expression of tumor-associated antigens and c-erbB-2 protein, together with the enhancement of that of MHC-Class I and ICAM-1, would help cytotoxic killer cells recognize the tumor cells. (author)

The detection of K88, K99 fimbrial antigen and enterotoxin genes of Escherichia coli isolated from piglets and calves with diarrhoea in Indonesia

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Supar

1996-03-01

Full Text Available Enterotoxigenic Escherichia coli (ETEC strains cause diarrhoeal disease in piglets and calves in Indonesia. These strains possess two virulence factors namely attachment and enterotoxin antigens . These factors could be detected phenotypically and genetically. Haemolytic Escherichia coli (E coli isolates possessing K88 fimbrial antigen associated with 0-group 108 and 149. They were positive for K88 gene and demonstrated their ability to produce heat labile enterotoxin (LT and genetically were all positive for LT gene . Seventeen isolates ofE coli K88 which associated with 0-group 149 were positive forSTb gene, other O-serotypes were negative . Ten isolates of Ecoli K88 which associated with 0-group 108 possessed K88, K99, LT and STa genes, but negative for STb gene . However, phenotypically the K99 antigen and STa toxin were not expressed under laboratory conditions, the reason was not well understood . E. coli K99 strains isolated from calves wit h diarrhoea were all associated with 0-group 9 and produced STa toxin when tested by suckling mousse bioassay. The E. coli K99 calf isolates were all hybridized with K99 and STa gene only . It is likely that K99 gene is associated with STa gene . The DNA hybridization technique is more convenience to be used for confirmation diagnosis of colibacillosis, however, not all veterinary laboratories could perform these tests .

Imaging gene expression in gene therapy

Energy Technology Data Exchange (ETDEWEB)

Wiebe, Leonard I. [Alberta Univ., Edmonton (Canada). Noujaim Institute for Pharmaceutical Oncology Research

1997-12-31

Full text. Gene therapy can be used to introduce new genes, or to supplement the function of indigenous genes. At the present time, however, there is non-invasive test to demonstrate efficacy of the gene transfer and expression processes. It has been postulated that scintigraphic imaging can offer unique information on both the site at which the transferred gene is expressed, and the degree of expression, both of which are critical issue for safety and clinical efficacy. Many current studies are based on `suicide gene therapy` of cancer. Cells modified to express these genes commit metabolic suicide in the presence of an enzyme encoded by the transferred gene and a specifically-convertible pro drug. Pro drug metabolism can lead to selective metabolic trapping, required for scintigraphy. Herpes simplex virus type-1 thymidine kinase (H S V-1 t k{sup +}) has been use for `suicide` in vivo tumor gene therapy. It has been proposed that radiolabelled nucleosides can be used as radiopharmaceuticals to detect H S V-1 t k{sup +} gene expression where the H S V-1 t k{sup +} gene serves a reporter or therapeutic function. Animal gene therapy models have been studied using purine-([{sup 18} F]F H P G; [{sup 18} F]-A C V), and pyrimidine- ([{sup 123}/{sup 131} I]I V R F U; [{sup 124}/{sup 131I}]) antiviral nucleosides. Principles of gene therapy and gene therapy imaging will be reviewed and experimental data for [{sup 123}/{sup 131I}]I V R F U imaging with the H S V-1 t k{sup +} reporter gene will be presented

Mosaic VSGs and the scale of Trypanosoma brucei antigenic variation.

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James P J Hall

Full Text Available A main determinant of prolonged Trypanosoma brucei infection and transmission and success of the parasite is the interplay between host acquired immunity and antigenic variation of the parasite variant surface glycoprotein (VSG coat. About 0.1% of trypanosome divisions produce a switch to a different VSG through differential expression of an archive of hundreds of silent VSG genes and pseudogenes, but the patterns and extent of the trypanosome diversity phenotype, particularly in chronic infection, are unclear. We applied longitudinal VSG cDNA sequencing to estimate variant richness and test whether pseudogenes contribute to antigenic variation. We show that individual growth peaks can contain at least 15 distinct variants, are estimated computationally to comprise many more, and that antigenically distinct 'mosaic' VSGs arise from segmental gene conversion between donor VSG genes or pseudogenes. The potential for trypanosome antigenic variation is probably much greater than VSG archive size; mosaic VSGs are core to antigenic variation and chronic infection.

Identification of transcription coactivator OCA-B-dependent genes involved in antigen-dependent B cell differentiation by cDNA array analyses.

Science.gov (United States)

Kim, Unkyu; Siegel, Rachael; Ren, Xiaodi; Gunther, Cary S; Gaasterland, Terry; Roeder, Robert G

2003-07-22

The tissue-specific transcriptional coactivator OCA-B is required for antigen-dependent B cell differentiation events, including germinal center formation. However, the identity of OCA-B target genes involved in this process is unknown. This study has used large-scale cDNA arrays to monitor changes in gene expression patterns that accompany mature B cell differentiation. B cell receptor ligation alone induces many genes involved in B cell expansion, whereas B cell receptor and helper T cell costimulation induce genes associated with B cell effector function. OCA-B expression is induced by both B cell receptor ligation alone and helper T cell costimulation, suggesting that OCA-B is involved in B cell expansion as well as B cell function. Accordingly, several genes involved in cell proliferation and signaling, such as Lck, Kcnn4, Cdc37, cyclin D3, B4galt1, and Ms4a11, have been identified as OCA-B-dependent genes. Further studies on the roles played by these genes in B cells will contribute to an understanding of B cell differentiation.

Genomic Characterization of Variable Surface Antigens Reveals a Telomere Position Effect as a Prerequisite for RNA Interference-Mediated Silencing in Paramecium tetraurelia

Science.gov (United States)

Baranasic, Damir; Oppermann, Timo; Cheaib, Miriam; Cullum, John; Schmidt, Helmut

2014-01-01

ABSTRACT Antigenic or phenotypic variation is a widespread phenomenon of expression of variable surface protein coats on eukaryotic microbes. To clarify the mechanism behind mutually exclusive gene expression, we characterized the genetic properties of the surface antigen multigene family in the ciliate Paramecium tetraurelia and the epigenetic factors controlling expression and silencing. Genome analysis indicated that the multigene family consists of intrachromosomal and subtelomeric genes; both classes apparently derive from different gene duplication events: whole-genome and intrachromosomal duplication. Expression analysis provides evidence for telomere position effects, because only subtelomeric genes follow mutually exclusive transcription. Microarray analysis of cultures deficient in Rdr3, an RNA-dependent RNA polymerase, in comparison to serotype-pure wild-type cultures, shows cotranscription of a subset of subtelomeric genes, indicating that the telomere position effect is due to a selective occurrence of Rdr3-mediated silencing in subtelomeric regions. We present a model of surface antigen evolution by intrachromosomal gene duplication involving the maintenance of positive selection of structurally relevant regions. Further analysis of chromosome heterogeneity shows that alternative telomere addition regions clearly affect transcription of closely related genes. Consequently, chromosome fragmentation appears to be of crucial importance for surface antigen expression and evolution. Our data suggest that RNAi-mediated control of this genetic network by trans-acting RNAs allows rapid epigenetic adaptation by phenotypic variation in combination with long-term genetic adaptation by Darwinian evolution of antigen genes. PMID:25389173

Targeted gene delivery to the synovial pannus in antigen-induced arthritis by ultrasound-targeted microbubble destruction in vivo.

Science.gov (United States)

Xiang, Xi; Tang, Yuanjiao; Leng, Qianying; Zhang, Lingyan; Qiu, Li

2016-02-01

The purpose of this study was to optimize an ultrasound-targeted microbubble destruction (UTMD) technique to improve the in vivo transfection efficiency of the gene encoding enhanced green fluorescent protein (EGFP) in the synovial pannus in an antigen-induced arthritis rabbit model. A mixture of microbubbles and plasmids was locally injected into the knee joints of an antigen-induced arthritis (AIA) rabbits. The plasmid concentrations and ultrasound conditions were varied in the experiments. We also tested local articular and intravenous injections. The rabbits were divided into five groups: (1) ultrasound+microbubbles+plasmid; (2) ultrasound+plasmid; (3) microbubble+plasmid; (4) plasmid only; (5) untreated controls. EGFP expression was observed by fluorescent microscope and immunohistochemical staining in the synovial pannus of each group. The optimal plasmid dosage and ultrasound parameter were determined based on the results of EGFP expression and the present and absent of tissue damage under light microscopy. The irradiation procedure was performed to observe the duration of the EGFP expression in the synovial pannus and other tissues and organs, as well as the damage to the normal cells. The optimal condition was determined to be a 1-MHz ultrasound pulse applied for 5 min with a power output of 2 W/cm(2) and a 20% duty cycle along with 300 μg of plasmid. Under these conditions, the synovial pannus showed significant EGFP expression without significant damage to the surrounding normal tissue. The EGFP expression induced by the local intra-articular injection was significantly more increased than that induced by the intravenous injection. The EGFP expression in the synovial pannus of the ultrasound+microbubbles+plasmid group was significantly higher than that of the other four groups (Ppannus of an AIA model. Thus, this could become a safe and effective non-viral gene transfection procedure for arthritis therapy. Copyright © 2015 Elsevier B.V. All rights

[Prokaryotic expression of recombinant prochymosin gene and its antiserum preparation].

Science.gov (United States)

Li, Xin-ping; Liu, Huan-huan; Pu, Yan; Zhang, Fu-chun; Li, Yi-jie

2012-07-01

To optimize the prochymosin (pCHY) gene codons and express the gene in Escherichia coli (E.coli), and to prepare its antiserum and detect chymosin protein specifically. According to codon usage bias of E.coli, prochymosin gene sequence was synthesized based on the conserved sequences of prochymosin gene from bovine, lamb and camel, and then cloned into the plasmid pET-30a and pcDNA3-AAT-COMP-C3d3 (pcD-ACC), respectively. pET-30a-pCHY was expressed, as the detected antigen, in E.coli BL21(DE3) after IPTG induction. RT-PCR was used to detect prochymosin mRNA expression in liver from the mice injected pcDNA3-AAT-COMP-pCHY-C3d3(pACCC) by hydrodynamics-based transfection method. To prepare the antiserum of prochymosin, pACCC and GST-pCHY proteins were used to immunize New Zealand rabbits in accordance with DNA prime-protein boost strategy. Antibody levels were tested by ELISA. Western blotting showed the molecular weight of His-pCHY protein was about 55 000, similar to the expected molecular size. ELISA demonstrated that the titer level of prochymosin antiserum was high. Based on the codon optimization, we have obtained high-titer prochymosin antiserum through DNA vaccine vector pcD-ACC combined with DNA prime-protein boost strategy, similar to that by protein vaccine.

[Expression and activity determination of recombinant capsid protein VP2 gene of enterovirus type 71].

Science.gov (United States)

Huang, Xueyong; Liu, Guohua; Hu, Xiaoning; Du, Yanhua; Li, Xingle; Xu, Yuling; Chen, Haomin; Xu, Bianli

2014-04-01

To clone and express the recombinant capsid protein VP2 of enterovirus type 71 (EV71) and to identify the immune activity of expressed protein in order to build a basis for the investigation work of vaccine and diagnostic antigen. VP2 gene of EV71 was amplified by PCR, and then was cut by restriction enzyme and inserted into expression vector pMAL-c2X. The positive recombinants were transferred into E.coli TB1, the genetically engineered bacteria including pMAL-c2X-VP2 plasmids were induced by isopropyl thiogalactoside ( IPTG) , and the expression products were analyzed by SDS-PAGE and western blotting method. EV71 IgM antibody detection method by ELISA was set up, and the sensitivity and specificity of this method was assessed; 60 neutralizing antibody positive serum samples from hand foot and mouth disease (HFMD) patients were determined, of which 52 samples were positive and 8 samples were negative; a total of 88 acute phase serum samples of HFMD patients diagnosed in clinical were also detected. VP2 gene of 762 bp was obtained by PCR, the gene segment inserted into the recombinant vector was identified using restriction enzyme digestion. The recombinant vector could express a specific about 71 500 fusion protein in E.coli by SDS-PAGE. The purified recombinant protein of EV71-VP2 can react with the serum of HFMD patients to produce a specific band by western blotting. The sensitivity and specificity of ELISA was 87% and 83%, respectively. Of the 88 acute phase serum samples from children with HFMD, 48 samples (55%) were positive by the ELISA assay. VP2 gene of EV71 has been cloned and a prokaryotic high expression system for VP2 gene was successfully constructed in the present study. The recombination EV71-VP2 has well antigenicity, which could be useful for developing diagnose reagent or vaccine of EV71.

Dynamics of antigen presentation to transgene product-specific CD4+ T cells and of Treg induction upon hepatic AAV gene transfer

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George Q Perrin

2016-01-01

Full Text Available The tolerogenic hepatic microenvironment impedes clearance of viral infections but is an advantage in viral vector gene transfer, which often results in immune tolerance induction to transgene products. Although the underlying tolerance mechanism has been extensively studied, our understanding of antigen presentation to transgene product-specific CD4+ T cells remains limited. To address this, we administered hepatotropic adeno-associated virus (AAV8 vector expressing cytoplasmic ovalbumin (OVA into wt mice followed by adoptive transfer of transgenic OVA-specific T cells. We find that that the liver-draining lymph nodes (celiac and portal are the major sites of MHC II presentation of the virally encoded antigen, as judged by in vivo proliferation of DO11.10 CD4+ T cells (requiring professional antigen-presenting cells, e.g., macrophages and CD4+CD25+FoxP3+ Treg induction. Antigen presentation in the liver itself contributes to activation of CD4+ T cells egressing from the liver. Hepatic-induced Treg rapidly disseminate through the systemic circulation. By contrast, a secreted OVA transgene product is presented in multiple organs, and OVA-specific Treg emerge in both the thymus and periphery. In summary, liver draining lymph nodes play an integral role in hepatic antigen presentation and peripheral Treg induction, which results in systemic regulation of the response to viral gene products.

Application of a scalable plant transient gene expression platform for malaria vaccine development

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Holger eSpiegel

2015-12-01

Full Text Available Despite decades of intensive research efforts there is currently no vaccine that provides sustained sterile immunity against malaria. In this context, a large number of targets from the different stages of the Plasmodium falciparum life cycle have been evaluated as vaccine candidates. None of these candidates has fulfilled expectations, and as long as we lack a single target that induces strain-transcending protective immune responses, combining key antigens from different life cycle stages seems to be the most promising route towards the development of efficacious malaria vaccines. After the identification of potential targets using approaches such as omics-based technology and reverse immunology, the rapid expression, purification and characterization of these proteins, as well as the generation and analysis of fusion constructs combining different promising antigens or antigen domains before committing to expensive and time consuming clinical development, represents one of the bottlenecks in the vaccine development pipeline. The production of recombinant proteins by transient gene expression in plants is a robust and versatile alternative to cell-based microbial and eukaryotic production platforms. The transfection of plant tissues and/or whole plants using Agrobacterium tumefaciens offers a low technical entry barrier, low costs and a high degree of flexibility embedded within a rapid and scalable workflow. Recombinant proteins can easily be targeted to different subcellular compartments according to their physicochemical requirements, including post-translational modifications, to ensure optimal yields of high quality product, and to support simple and economical downstream processing. Here we demonstrate the use of a plant transient expression platform based on transfection with A. tumefaciens as essential component of a malaria vaccine development workflow involving screens for expression, solubility and stability using fluorescent fusion

Analysis of gene expression profile microarray data in complex regional pain syndrome.

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Tan, Wulin; Song, Yiyan; Mo, Chengqiang; Jiang, Shuangjian; Wang, Zhongxing

2017-09-01

The aim of the present study was to predict key genes and proteins associated with complex regional pain syndrome (CRPS) using bioinformatics analysis. The gene expression profiling microarray data, GSE47603, which included peripheral blood samples from 4 patients with CRPS and 5 healthy controls, was obtained from the Gene Expression Omnibus (GEO) database. The differentially expressed genes (DEGs) in CRPS patients compared with healthy controls were identified using the GEO2R online tool. Functional enrichment analysis was then performed using The Database for Annotation Visualization and Integrated Discovery online tool. Protein‑protein interaction (PPI) network analysis was subsequently performed using Search Tool for the Retrieval of Interaction Genes database and analyzed with Cytoscape software. A total of 257 DEGs were identified, including 243 upregulated genes and 14 downregulated ones. Genes in the human leukocyte antigen (HLA) family were most significantly differentially expressed. Enrichment analysis demonstrated that signaling pathways, including immune response, cell motion, adhesion and angiogenesis were associated with CRPS. PPI network analysis revealed that key genes, including early region 1A binding protein p300 (EP300), CREB‑binding protein (CREBBP), signal transducer and activator of transcription (STAT)3, STAT5A and integrin α M were associated with CRPS. The results suggest that the immune response may therefore serve an important role in CRPS development. In addition, genes in the HLA family, such as HLA‑DQB1 and HLA‑DRB1, may present potential biomarkers for the diagnosis of CRPS. Furthermore, EP300, its paralog CREBBP, and the STAT family genes, STAT3 and STAT5 may be important in the development of CRPS.

In Vitro Pre-Clinical Validation of Suicide Gene Modified Anti-CD33 Redirected Chimeric Antigen Receptor T-Cells for Acute Myeloid Leukemia.

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Kentaro Minagawa

Full Text Available Approximately fifty percent of patients with acute myeloid leukemia can be cured with current therapeutic strategies which include, standard dose chemotherapy for patients at standard risk of relapse as assessed by cytogenetic and molecular analysis, or high-dose chemotherapy with allogeneic hematopoietic stem cell transplant for high-risk patients. Despite allogeneic hematopoietic stem cell transplant about 25% of patients still succumb to disease relapse, therefore, novel strategies are needed to improve the outcome of patients with acute myeloid leukemia.We developed an immunotherapeutic strategy targeting the CD33 myeloid antigen, expressed in ~ 85-90% of patients with acute myeloid leukemia, using chimeric antigen receptor redirected T-cells. Considering that administration of CAR T-cells has been associated with cytokine release syndrome and other potential off-tumor effects in patients, safety measures were here investigated and reported. We genetically modified human activated T-cells from healthy donors or patients with acute myeloid leukemia with retroviral supernatant encoding the inducible Caspase9 suicide gene, a ΔCD19 selectable marker, and a humanized third generation chimeric antigen receptor recognizing human CD33. ΔCD19 selected inducible Caspase9-CAR.CD33 T-cells had a 75±3.8% (average ± standard error of the mean chimeric antigen receptor expression, were able to specifically lyse CD33+ targets in vitro, including freshly isolated leukemic blasts from patients, produce significant amount of tumor-necrosis-factor-alpha and interferon-gamma, express the CD107a degranulation marker, and proliferate upon antigen specific stimulation. Challenging ΔCD19 selected inducible Caspase9-CAR.CD33 T-cells with programmed-death-ligand-1 enriched leukemia blasts resulted in significant killing like observed for the programmed-death-ligand-1 negative leukemic blasts fraction. Since the administration of 10 nanomolar of a non

Recruitment of PfSET2 by RNA polymerase II to variant antigen encoding loci contributes to antigenic variation in P. falciparum.

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Uchechi E Ukaegbu

2014-01-01

Full Text Available Histone modifications are important regulators of gene expression in all eukaryotes. In Plasmodium falciparum, these epigenetic marks regulate expression of genes involved in several aspects of host-parasite interactions, including antigenic variation. While the identities and genomic positions of many histone modifications have now been cataloged, how they are targeted to defined genomic regions remains poorly understood. For example, how variant antigen encoding loci (var are targeted for deposition of unique histone marks is a mystery that continues to perplex the field. Here we describe the recruitment of an ortholog of the histone modifier SET2 to var genes through direct interactions with the C-terminal domain (CTD of RNA polymerase II. In higher eukaryotes, SET2 is a histone methyltransferase recruited by RNA pol II during mRNA transcription; however, the ortholog in P. falciparum (PfSET2 has an atypical architecture and its role in regulating transcription is unknown. Here we show that PfSET2 binds to the unphosphorylated form of the CTD, a property inconsistent with its recruitment during mRNA synthesis. Further, we show that H3K36me3, the epigenetic mark deposited by PfSET2, is enriched at both active and silent var gene loci, providing additional evidence that its recruitment is not associated with mRNA production. Over-expression of a dominant negative form of PfSET2 designed to disrupt binding to RNA pol II induced rapid var gene expression switching, confirming both the importance of PfSET2 in var gene regulation and a role for RNA pol II in its recruitment. RNA pol II is known to transcribe non-coding RNAs from both active and silent var genes, providing a possible mechanism by which it could recruit PfSET2 to var loci. This work unifies previous reports of histone modifications, the production of ncRNAs, and the promoter activity of var introns into a mechanism that contributes to antigenic variation by malaria parasites.

Cloning and expression of pab gene of M. tuberculosis isolated from pulmonary TB patient in E.coli DH5α

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Tri Y. M. Raras

2011-11-01

Full Text Available Background: Mycobacterium tuberculosis antigen38 is a potent serodiagnostic agent containing two M. tuberculosisspecific B-cell epitopes. The high price of imported diagnostic agents hinders realization of fast clinical TB diagnosis in developing countries. Therefore, we produced recombinant antigen38 (recAg38M from M. tuberculosis local strain, which might be used to produce economical tuberculosis serodiagnostic kit.Methods: Pab gene that was isolated from pulmonary TB patient in Malang was cloned into a plasmid vector (pGEMTeasy to construct pMB38. The E.coli DH5α clone carrying pMb38 was selected on X-gal medium. The expression of pab was mediated using pPRoExHTc under the control of Trc promoter and E.coli DH5α as host.Results: Alignment of the pab sequence from the white E.coli DH5α clones with that of M. tuberculosis H37Rv showed 98% homology. The recombinant protein in which the signal peptide has been deleted to prevent the protein being secreted into medium was found in the cytoplasm.Conclusion: pab gene of M. tuberculosis isolated from a TB patient could be expressed in heterologous system in E.coliDH5α. (Med J Indones 2011; 20:247-54Keywords: Mycobacterium tuberculosis, Pab gene expression, recombinant antigen38

Circulating MicroRNAs in Plasma of Hepatitis B e Antigen Positive Children Reveal Liver-Specific Target Genes

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Winther, Thilde Nordmann; Jacobsen, Kari Stougaard; Mirza, Aashiq Hussain

2014-01-01

Background and Aim. Hepatitis B e antigen positive (HBeAg-positive) children are at high risk of severe complications such as hepatocellular carcinoma and cirrhosis. Liver damage is caused by the host immune response to infected hepatocytes, and we hypothesise that specific microRNAs play a role...... in this complex interaction between virus and host. The study aimed to identify microRNAs with aberrant plasma expressions in HBeAg-positive children and with liver-specific target genes. Methods. By revisiting our previous screen of microRNA plasma levels in HBeAg-positive and HBeAg-negative children...... with chronic hepatitis B (CHB) and in healthy controls, candidate microRNAs with aberrant plasma expressions in HBeAg-positive children were identified. MicroRNAs targeting liver-specific genes were selected based on bioinformatics analysis and validated by qRT-PCR using plasma samples from 34 HBe...

Validation of suitable reference genes for expression normalization in Echinococcus spp. larval stages.

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Espínola, Sergio Martin; Ferreira, Henrique Bunselmeyer; Zaha, Arnaldo

2014-01-01

In recent years, a significant amount of sequence data (both genomic and transcriptomic) for Echinococcus spp. has been published, thereby facilitating the analysis of genes expressed during a specific stage or involved in parasite development. To perform a suitable gene expression quantification analysis, the use of validated reference genes is strongly recommended. Thus, the aim of this work was to identify suitable reference genes to allow reliable expression normalization for genes of interest in Echinococcus granulosus sensu stricto (s.s.) (G1) and Echinococcus ortleppi upon induction of the early pre-adult development. Untreated protoscoleces (PS) and pepsin-treated protoscoleces (PSP) from E. granulosus s.s. (G1) and E. ortleppi metacestode were used. The gene expression stability of eleven candidate reference genes (βTUB, NDUFV2, RPL13, TBP, CYP-1, RPII, EF-1α, βACT-1, GAPDH, ETIF4A-III and MAPK3) was assessed using geNorm, Normfinder, and RefFinder. Our qPCR data showed a good correlation with the recently published RNA-seq data. Regarding expression stability, EF-1α and TBP were the most stable genes for both species. Interestingly, βACT-1 (the most commonly used reference gene), and GAPDH and ETIF4A-III (previously identified as housekeeping genes) did not behave stably in our assay conditions. We propose the use of EF-1α as a reference gene for studies involving gene expression analysis in both PS and PSP experimental conditions for E. granulosus s.s. and E. ortleppi. To demonstrate its applicability, EF-1α was used as a normalizer gene in the relative quantification of transcripts from genes coding for antigen B subunits. The same EF-1α reference gene may be used in studies with other Echinococcus sensu lato species. This report validates suitable reference genes for species of class Cestoda, phylum Platyhelminthes, thus providing a foundation for further validation in other epidemiologically important cestode species, such as those from the

Validation of Suitable Reference Genes for Expression Normalization in Echinococcus spp. Larval Stages

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Espínola, Sergio Martin; Ferreira, Henrique Bunselmeyer; Zaha, Arnaldo

2014-01-01

In recent years, a significant amount of sequence data (both genomic and transcriptomic) for Echinococcus spp. has been published, thereby facilitating the analysis of genes expressed during a specific stage or involved in parasite development. To perform a suitable gene expression quantification analysis, the use of validated reference genes is strongly recommended. Thus, the aim of this work was to identify suitable reference genes to allow reliable expression normalization for genes of interest in Echinococcus granulosus sensu stricto (s.s.) (G1) and Echinococcus ortleppi upon induction of the early pre-adult development. Untreated protoscoleces (PS) and pepsin-treated protoscoleces (PSP) from E. granulosus s.s. (G1) and E. ortleppi metacestode were used. The gene expression stability of eleven candidate reference genes (βTUB, NDUFV2, RPL13, TBP, CYP-1, RPII, EF-1α, βACT-1, GAPDH, ETIF4A-III and MAPK3) was assessed using geNorm, Normfinder, and RefFinder. Our qPCR data showed a good correlation with the recently published RNA-seq data. Regarding expression stability, EF-1α and TBP were the most stable genes for both species. Interestingly, βACT-1 (the most commonly used reference gene), and GAPDH and ETIF4A-III (previously identified as housekeeping genes) did not behave stably in our assay conditions. We propose the use of EF-1α as a reference gene for studies involving gene expression analysis in both PS and PSP experimental conditions for E. granulosus s.s. and E. ortleppi. To demonstrate its applicability, EF-1α was used as a normalizer gene in the relative quantification of transcripts from genes coding for antigen B subunits. The same EF-1α reference gene may be used in studies with other Echinococcus sensu lato species. This report validates suitable reference genes for species of class Cestoda, phylum Platyhelminthes, thus providing a foundation for further validation in other epidemiologically important cestode species, such as those from the

Synthesis and expression of CDw75 antigen in human colorectal cancer

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Costa-Nogueira, Clotilde; Villar-Portela, Susana; Cuevas, Elisa; Gil-Martín, Emilio; Fernández-Briera, Almudena

2009-01-01

Increased ST6Gal I activity has been associated with the α(2,6)sialylation enhancement of membrane glycoconjugates observed in metastatic colorectal carcinomas (CRC). Siaα(2,6)Galβ(1,4)GlcNAc sequence, known as CDw75, is a sialylated carbohydrate determinant generated by the ST6Gal I. This epitope has been reported to be associated with the progression of gastric and colorectal tumours, hence there are only a few conclusive studies to date. By radioisotopic techniques we evaluated the ST6Gal I activity in healthy, transitional and tumour tissues from 43 patients with CRC. By immunohistochemistry we assessed the CDw75 expression in 25 colorectal adenomas, 43 tumours, 13 transitional and 28 healthy tissues of CRC patients. ST6Gal I activity was likewise found to be statistically higher in tumour tissue respect to healthy tissue from CRC patients. CDw75 expression was positive in 20% of colorectal adenomas. Furthermore, 70% of tumour specimens and 8.3% of transitional specimens were positive for CDw75 expression, whereas none of the healthy ones showed the presence of the epitope. The major contribution of this study is the inclusion of data from transitional tissue and the analysis of CDw75 antigen expression in CRC and in colorectal adenomas, little known so far. ST6Gal I activity and CDw75 antigen expression were increased in CRC. Although their comparison did not reach the statistical significance, a great extent of patients showed both, an enhanced tumour ST6Gal I activity and an increased CDw75 expression in the tumour tissue. So, these two variables may play a role in malignant transformation. The expression of CDw75 in colorectal adenomas suggests that this antigen may be a tumour marker in CRC

Trans-acting GC-rich non-coding RNA at var expression site modulates gene counting in malaria parasite.

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Guizetti, Julien; Barcons-Simon, Anna; Scherf, Artur

2016-11-16

Monoallelic expression of the var multigene family enables immune evasion of the malaria parasite Plasmodium falciparum in its human host. At a given time only a single member of the 60-member var gene family is expressed at a discrete perinuclear region called the 'var expression site'. However, the mechanism of var gene counting remains ill-defined. We hypothesize that activation factors associating specifically with the expression site play a key role in this process. Here, we investigate the role of a GC-rich non-coding RNA (ncRNA) gene family composed of 15 highly homologous members. GC-rich genes are positioned adjacent to var genes in chromosome-central gene clusters but are absent near subtelomeric var genes. Fluorescence in situ hybridization demonstrates that GC-rich ncRNA localizes to the perinuclear expression site of central and subtelomeric var genes in trans. Importantly, overexpression of distinct GC-rich ncRNA members disrupts the gene counting process at the single cell level and results in activation of a specific subset of var genes in distinct clones. We identify the first trans-acting factor targeted to the elusive perinuclear var expression site and open up new avenues to investigate ncRNA function in antigenic variation of malaria and other protozoan pathogens. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

Genetic diversity of K-antigen gene clusters of Escherichia coli and their molecular typing using a suspension array.

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Yang, Shuang; Xi, Daoyi; Jing, Fuyi; Kong, Deju; Wu, Junli; Feng, Lu; Cao, Boyang; Wang, Lei

2018-04-01

Capsular polysaccharides (CPSs), or K-antigens, are the major surface antigens of Escherichia coli. More than 80 serologically unique K-antigens are classified into 4 groups (Groups 1-4) of capsules. Groups 1 and 4 contain the Wzy-dependent polymerization pathway and the gene clusters are in the order galF to gnd; Groups 2 and 3 contain the ABC-transporter-dependent pathway and the gene clusters consist of 3 regions, regions 1, 2 and 3. Little is known about the variations among the gene clusters. In this study, 9 serotypes of K-antigen gene clusters (K2ab, K11, K20, K24, K38, K84, K92, K96, and K102) were sequenced and correlated with their CPS chemical structures. On the basis of sequence data, a K-antigen-specific suspension array that detects 10 distinct CPSs, including the above 9 CPSs plus K30, was developed. This is the first report to catalog the genetic features of E. coli K-antigen variations and to develop a suspension array for their molecular typing. The method has a number of advantages over traditional bacteriophage and serum agglutination methods and lays the foundation for straightforward identification and detection of additional K-antigens in the future.

Genetic diversity and antigenicity variation of Babesia bovis merozoite surface antigen-1 (MSA-1) in Thailand.

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Tattiyapong, Muncharee; Sivakumar, Thillaiampalam; Takemae, Hitoshi; Simking, Pacharathon; Jittapalapong, Sathaporn; Igarashi, Ikuo; Yokoyama, Naoaki

2016-07-01

Babesia bovis, an intraerythrocytic protozoan parasite, causes severe clinical disease in cattle worldwide. The genetic diversity of parasite antigens often results in different immune profiles in infected animals, hindering efforts to develop immune control methodologies against the B. bovis infection. In this study, we analyzed the genetic diversity of the merozoite surface antigen-1 (msa-1) gene using 162 B. bovis-positive blood DNA samples sourced from cattle populations reared in different geographical regions of Thailand. The identity scores shared among 93 msa-1 gene sequences isolated by PCR amplification were 43.5-100%, and the similarity values among the translated amino acid sequences were 42.8-100%. Of 23 total clades detected in our phylogenetic analysis, Thai msa-1 gene sequences occurred in 18 clades; seven among them were composed of sequences exclusively from Thailand. To investigate differential antigenicity of isolated MSA-1 proteins, we expressed and purified eight recombinant MSA-1 (rMSA-1) proteins, including an rMSA-1 from B. bovis Texas (T2Bo) strain and seven rMSA-1 proteins based on the Thai msa-1 sequences. When these antigens were analyzed in a western blot assay, anti-T2Bo cattle serum strongly reacted with the rMSA-1 from T2Bo, as well as with three other rMSA-1 proteins that shared 54.9-68.4% sequence similarity with T2Bo MSA-1. In contrast, no or weak reactivity was observed for the remaining rMSA-1 proteins, which shared low sequence similarity (35.0-39.7%) with T2Bo MSA-1. While demonstrating the high genetic diversity of the B. bovis msa-1 gene in Thailand, the present findings suggest that the genetic diversity results in antigenicity variations among the MSA-1 antigens of B. bovis in Thailand. Copyright © 2016 Elsevier B.V. All rights reserved.

Sarcocystis neurona merozoites express a family of immunogenic surface antigens that are orthologues of the Toxoplasma gondii surface antigens (SAGs) and SAG-related sequences.

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Howe, Daniel K; Gaji, Rajshekhar Y; Mroz-Barrett, Meaghan; Gubbels, Marc-Jan; Striepen, Boris; Stamper, Shelby

2005-02-01

Sarcocystis neurona is a member of the Apicomplexa that causes myelitis and encephalitis in horses but normally cycles between the opossum and small mammals. Analysis of an S. neurona expressed sequence tag (EST) database revealed four paralogous proteins that exhibit clear homology to the family of surface antigens (SAGs) and SAG-related sequences of Toxoplasma gondii. The primary peptide sequences of the S. neurona proteins are consistent with the two-domain structure that has been described for the T. gondii SAGs, and each was predicted to have an amino-terminal signal peptide and a carboxyl-terminal glycolipid anchor addition site, suggesting surface localization. All four proteins were confirmed to be membrane associated and displayed on the surface of S. neurona merozoites. Due to their surface localization and homology to T. gondii surface antigens, these S. neurona proteins were designated SnSAG1, SnSAG2, SnSAG3, and SnSAG4. Consistent with their homology, the SnSAGs elicited a robust immune response in infected and immunized animals, and their conserved structure further suggests that the SnSAGs similarly serve as adhesins for attachment to host cells. Whether the S. neurona SAG family is as extensive as the T. gondii SAG family remains unresolved, but it is probable that additional SnSAGs will be revealed as more S. neurona ESTs are generated. The existence of an SnSAG family in S. neurona indicates that expression of multiple related surface antigens is not unique to the ubiquitous organism T. gondii. Instead, the SAG gene family is a common trait that presumably has an essential, conserved function(s).

Sarcocystis neurona Merozoites Express a Family of Immunogenic Surface Antigens That Are Orthologues of the Toxoplasma gondii Surface Antigens (SAGs) and SAG-Related Sequences†

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Howe, Daniel K.; Gaji, Rajshekhar Y.; Mroz-Barrett, Meaghan; Gubbels, Marc-Jan; Striepen, Boris; Stamper, Shelby

2005-01-01

Sarcocystis neurona is a member of the Apicomplexa that causes myelitis and encephalitis in horses but normally cycles between the opossum and small mammals. Analysis of an S. neurona expressed sequence tag (EST) database revealed four paralogous proteins that exhibit clear homology to the family of surface antigens (SAGs) and SAG-related sequences of Toxoplasma gondii. The primary peptide sequences of the S. neurona proteins are consistent with the two-domain structure that has been described for the T. gondii SAGs, and each was predicted to have an amino-terminal signal peptide and a carboxyl-terminal glycolipid anchor addition site, suggesting surface localization. All four proteins were confirmed to be membrane associated and displayed on the surface of S. neurona merozoites. Due to their surface localization and homology to T. gondii surface antigens, these S. neurona proteins were designated SnSAG1, SnSAG2, SnSAG3, and SnSAG4. Consistent with their homology, the SnSAGs elicited a robust immune response in infected and immunized animals, and their conserved structure further suggests that the SnSAGs similarly serve as adhesins for attachment to host cells. Whether the S. neurona SAG family is as extensive as the T. gondii SAG family remains unresolved, but it is probable that additional SnSAGs will be revealed as more S. neurona ESTs are generated. The existence of an SnSAG family in S. neurona indicates that expression of multiple related surface antigens is not unique to the ubiquitous organism T. gondii. Instead, the SAG gene family is a common trait that presumably has an essential, conserved function(s). PMID:15664946

The SnSAG merozoite surface antigens of Sarcocystis neurona are expressed differentially during the bradyzoite and sporozoite life cycle stages.

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Gautam, A; Dubey, J P; Saville, W J; Howe, D K

2011-12-29

Sarcocystis neurona is a two-host coccidian parasite whose complex life cycle progresses through multiple developmental stages differing at morphological and molecular levels. The S. neurona merozoite surface is covered by multiple, related glycosylphosphatidylinositol-linked proteins, which are orthologous to the surface antigen (SAG)/SAG1-related sequence (SRS) gene family of Toxoplasma gondii. Expression of the SAG/SRS proteins in T. gondii and another related parasite Neospora caninum is life-cycle stage specific and seems necessary for parasite transmission and persistence of infection. In the present study, the expression of S. neurona merozoite surface antigens (SnSAGs) was evaluated in the sporozoite and bradyzoite stages. Western blot analysis was used to compare SnSAG expression in merozoites versus sporozoites, while immunocytochemistry was performed to examine expression of the SnSAGs in merozoites versus bradyzoites. These analyses revealed that SnSAG2, SnSAG3 and SnSAG4 are expressed in sporozoites, while SnSAG5 was appeared to be downregulated in this life cycle stage. In S. neurona bradyzoites, it was found that SnSAG2, SnSAG3, SnSAG4 and SnSAG5 were either absent or expression was greatly reduced. As shown for T. gondii, stage-specific expression of the SnSAGs may be important for the parasite to progress through its developmental stages and complete its life cycle successfully. Thus, it is possible that the SAG switching mechanism by these parasites could be exploited as a point of intervention. As well, the alterations in surface antigen expression during different life cycle stages may need to be considered when designing prospective approaches for protective vaccination. Copyright © 2011 Elsevier B.V. All rights reserved.

Leukemia Associated Antigens: Their Dual Role as Biomarkers and Immunotherapeutic Targets for Acute Myeloid Leukemia

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Michael Schmitt

2007-01-01

Full Text Available Leukemia associated antigens (LAAs are being increasingly identified by methods such as cytotoxic T-lymphocyte (CTL cloning, serological analysis of recombinant cDNA expression libraries (SEREX and mass spectrometry (MS. In additional, large scale screening techniques such as microarray, single nucleotide polymorphisms (SNPs, serial analysis of gene expression (SAGE and 2-dimensional gel electrophoresis (2-DE have expanded our understanding of the role that tumor antigens play in the biological processes which are perturbed in acute myeloid leukemia (AML. It has become increasingly apparent that these antigens play a dual role, not only as targets for immunotherapy, but also as biomarkers of disease state, stage, response to treatment and survival. We need biomarkers to enable the identification of the patients who are most likely to benefit from specific treatments (conventional and/or novel and to help clinicians and scientists improve clinical end points and treatment design. Here we describe the LAAs identified in AML, to date, which have already been shown to play a dual role as biomarkers of AML disease.Abbreviations: AML: acute myeloid leukemia; APL: acute promyelocytic leukemia; ATRA: all-trans-retinoic acid; B-CLL: B-cell chronic lymphocytic leukemia; CT: cancer-testis; CTL: cytotoxic T-lymphocyte; FAB: French-American-British; HI: hypusination inhibitors; HSP: heat shock protein; ITD: internal tandem duplication; LAA: leukemia associated antigen; MDS: myelodysplastic syndrome; MGEA6: meningioma antigen 6; MPD: myeloproliferative disease; MS: mass spectrometry; NK: natural killer; PRAME: preferentially expressed antigen of melanoma; PRTN3: proteinase 3; RAGE-1: renal antigen 1; RHAMM: receptor for hyaluronic acid-mediated motility; RQ-PCR: real-time PCR; SAGE: serial analysis of gene expression; SCT: stem cell transplant; SEREX: serological analysis of recombinant cDNA expression libraries; SNPs: single nucleotide polymorphisms; UPD

Recovery of human metapneumovirus from cDNA: optimization of growth in vitro and expression of additional genes

International Nuclear Information System (INIS)

Biacchesi, Stephane; Skiadopoulos, Mario H.; Tran, Kim C.; Murphy, Brian R.; Collins, Peter L.; Buchholz, Ursula J.

2004-01-01

essentially the same as rHMPV-GFP. Northern blot analysis showed that the increased number and promoter-proximal location of the added copies of the F and G genes resulted in a more than 6- and 14-fold increase in the expression of F and G mRNA, respectively, and sequence analysis confirmed the intactness of the added genes in recovered virus. Thus, it should be feasible to construct an HMPV vaccine virus containing extra copies of the G and F putative protective antigen genes to increase antigen expression or to provide representation of additional antigenic lineages or subgroups of HMPV

Stabilization of Transfected Cells Expressing Low-Incidence Blood Group Antigens: Novel Methods Facilitating Their Use as Reagent-Cells.

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Cecilia González

Full Text Available The identification of erythrocyte antibodies in the serum of patients rely on panels of human red blood cells (RBCs, which coexpress many antigens and are not easily available for low-incidence blood group phenotypes. These problems have been addressed by generating cell lines expressing unique blood group antigens, which may be used as an alternative to human RBCs. However, the use of cell lines implies several drawbacks, like the requirement of cell culture facilities and the high cost of cryopreservation. The application of cell stabilization methods could facilitate their use as reagent cells in clinical laboratories.We generated stably-transfected cells expressing low-incidence blood group antigens (Dia and Lua. High-expresser clones were used to assess the effect of TransFix® treatment and lyophilization as cell preservation methods. Cells were kept at 4°C and cell morphology, membrane permeability and antigenic properties were evaluated at several time-points after treatment.TransFix® addition to cell suspensions allows cell stabilization and proper antigen detection for at least 120 days, despite an increase in membrane permeability and a reduction in antigen expression levels. Lyophilized cells showed minor morphological changes and antigen expression levels were rather conserved at days 1, 15 and 120, indicating a high stability of the freeze-dried product. These stabilized cells have been proved to react specifically with human sera containing alloantibodies.Both stabilization methods allow long-term preservation of the transfected cells antigenic properties and may facilitate their distribution and use as reagent-cells expressing low-incidence antigens, overcoming the limited availability of such rare RBCs.

Quantitative Analyses of Core Promoters Enable Precise Engineering of Regulated Gene Expression in Mammalian Cells

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Ede, Christopher; Chen, Ximin; Lin, Meng-Yin; Chen, Yvonne Y.

2016-01-01

Inducible transcription systems play a crucial role in a wide array of synthetic biology circuits. However, the majority of inducible promoters are constructed from a limited set of tried-and-true promoter parts, which are susceptible to common shortcomings such as high basal expression levels (i.e., leakiness). To expand the toolbox for regulated mammalian gene expression and facilitate the construction of mammalian genetic circuits with precise functionality, we quantitatively characterized a panel of eight core promoters, including sequences with mammalian, viral, and synthetic origins. We demonstrate that this selection of core promoters can provide a wide range of basal gene expression levels and achieve a gradient of fold-inductions spanning two orders of magnitude. Furthermore, commonly used parts such as minimal CMV and minimal SV40 promoters were shown to achieve robust gene expression upon induction, but also suffer from high levels of leakiness. In contrast, a synthetic promoter, YB_TATA, was shown to combine low basal expression with high transcription rate in the induced state to achieve significantly higher fold-induction ratios compared to all other promoters tested. These behaviors remain consistent when the promoters are coupled to different genetic outputs and different response elements, as well as across different host-cell types and DNA copy numbers. We apply this quantitative understanding of core promoter properties to the successful engineering of human T cells that respond to antigen stimulation via chimeric antigen receptor signaling specifically under hypoxic environments. Results presented in this study can facilitate the design and calibration of future mammalian synthetic biology systems capable of precisely programmed functionality. PMID:26883397

Cell differentiation in cardiac myxomas: confocal microscopy and gene expression analysis after laser capture microdissection.

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Pucci, Angela; Mattioli, Claudia; Matteucci, Marco; Lorenzini, Daniele; Panvini, Francesca; Pacini, Simone; Ippolito, Chiara; Celiento, Michele; De Martino, Andrea; Dolfi, Amelio; Belgio, Beatrice; Bortolotti, Uberto; Basolo, Fulvio; Bartoloni, Giovanni

2018-05-22

Cardiac myxomas are rare tumors with a heterogeneous cell population including properly neoplastic (lepidic), endothelial and smooth muscle cells. The assessment of neoplastic (lepidic) cell differentiation pattern is rather difficult using conventional light microscopy immunohistochemistry and/or whole tissue extracts for mRNA analyses. In a preliminary study, we investigated 20 formalin-fixed and paraffin-embedded cardiac myxomas by means of conventional immunohistochemistry; in 10/20 cases, cell differentiation was also analyzed by real-time RT-PCR after laser capture microdissection of the neoplastic cells, whereas calretinin and endothelial antigen CD31 immunoreactivity was localized in 4/10 cases by double immunofluorescence confocal microscopy. Gene expression analyses of α-smooth muscle actin, endothelial CD31 antigen, alpha-cardiac actin, matrix metalloprotease-2 (MMP2) and tissue inhibitor of matrix metalloprotease-1 (TIMP1) was performed on cDNA obtained from either microdissected neoplastic cells or whole tumor sections. We found very little or absent CD31 and α-Smooth Muscle Actin expression in the microdissected cells as compared to the whole tumors, whereas TIMP1 and MMP2 genes were highly expressed in both ones, greater levels being found in patients with embolic phenomena. α-Cardiac Actin was not detected. Confocal microscopy disclosed two different signals corresponding to calretinin-positive myxoma cells and to endothelial CD31-positive cells, respectively. In conclusion, the neoplastic (lepidic) cells showed a distinct gene expression pattern and no consistent overlapping with endothelial and smooth muscle cells or cardiac myocytes; the expression of TIMP1 and MMP2 might be related to clinical presentation; larger series studies using also systematic transcriptome analysis might be useful to confirm the present results.

Blood group antigen A type 3 expression is a favorable prognostic factor in advanced NSCLC.

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Schmidt, L H; Kuemmel, A; Schliemann, C; Schulze, A; Humberg, J; Mohr, M; Görlich, D; Hartmann, W; Bröckling, S; Marra, A; Hillejan, L; Goletz, S; Karsten, U; Berdel, W E; Spieker, T; Wiewrodt, R

2016-02-01

Several blood group-related carbohydrate antigens are prognosis-relevant markers of tumor tissues. A type 3 (repetitive A) is a blood group antigen specific for A1 erythrocytes. Its potential expression in tumor tissues has so far not been examined. We have evaluated its expression in normal lung and in lung cancer using a novel antibody (A69-A/E8). For comparison an anti-A antibody specific to A types 1 and 2 was used, because its expression on lung cancer tissue has been previously reported to be of prognostic relevance. Resected tissue samples of 398 NSCLC patients were analyzed in immunohistochemistry using tissue microarrays. Expression of A type 3 was not observed in non-malignant lung tissues. A type 3 was expressed on tumor cells of around half of NSCLC patients of blood group A1 (ptype 1/2 antigen was observed (p=0.562), the expression of A type 3 by tumor cells indicated a highly significant favorable prognosis among advanced NSCLC patients (p=0.011) and in NSCLC patients with lymphatic spread (p=0.014). Univariate prognostic results were confirmed in a Cox proportional hazards model. In this study we present for the first time prognostic data for A type 3 antigen expression in lung cancer patients. Prospective studies should be performed to confirm the prognostic value of A type 3 expression for an improved risk stratification in NSCLC patients. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Cloning and Expression of Fusion Genes of Domain A-1 Protective Antigen of Bacillus Anthracis and Shigella Enterotoxin B Subunit (Stxb In E. Coil

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AH ahmadi

2015-02-01

Conclusion: The findings of the current study revealed that this antigen can be raised as an anti-cancer and recombinant vaccine candidate against types of Shigella, Escherichia coli and Bacillus anthracis which can be due to such factors as identification of antigen(PA by antibody PA20, its apoptosis induction properties, property of immunogenicity, adjuvant and delivery of STxB protein and high expression levels of Gb3 in human cancer cells.

Expression cloning of camelid nanobodies specific for Xenopus embryonic antigens.

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Keiji Itoh

Full Text Available Developmental biology relies heavily on the use of conventional antibodies, but their production and maintenance involves significant effort. Here we use an expression cloning approach to identify variable regions of llama single domain antibodies (known as nanobodies, which recognize specific embryonic antigens. A nanobody cDNA library was prepared from lymphocytes of a llama immunized with Xenopus embryo lysates. Pools of bacterially expressed cDNAs were sib-selected for the ability to produce specific staining patterns in gastrula embryos. Three different nanobodies were isolated: NbP1 and NbP3 stained yolk granules, while the reactivity of NbP7 was predominantly restricted to the cytoplasm and the cortex. The isolated nanobodies recognized specific protein bands in immunoblot analysis. A reverse proteomic approach identified NbP1 target antigen as EP45/Seryp, a serine protease inhibitor. Given the unique stability of nanobodies and the ease of their expression in diverse systems, we propose that nanobody cDNA libraries represent a promising resource for molecular markers for developmental biology.

Genetic identity and differential gene expression between Trichomonas vaginalis and Trichomonas tenax

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Mundodi Vasanthakrishna

2009-03-01

Full Text Available Abstract Background Trichomonas vaginalis is a human urogenital pathogen responsible for trichomonosis, the number-one, non-viral sexually transmitted disease (STD worldwide, while T. tenax is a commensal of the human oral cavity, found particularly in patients with poor oral hygiene and advanced periodontal disease. The extent of genetic identity between T. vaginalis and its oral commensal counterpart is unknown. Results Genes that were differentially expressed in T. vaginalis were identified by screening three independent subtraction cDNA libraries enriched for T. vaginalis genes. The same thirty randomly selected cDNA clones encoding for proteins with specific functions associated with colonization were identified from each of the subtraction cDNA libraries. In addition, a T. vaginalis cDNA expression library was screened with patient sera that was first pre-adsorbed with an extract of T. tenax antigens, and seven specific cDNA clones were identified from this cDNA library. Interestingly, some of the clones identified by the subtraction cDNA screening were also obtained from the cDNA expression library with the pre-adsorbed sera. Moreover and noteworthy, clones identified by both the procedures were found to be up-regulated in expression in T. vaginalis upon contact with vaginal epithelial cells, suggesting a role for these gene products in host colonization. Semi-quantitative RT-PCR analysis of select clones showed that the genes were not unique to T. vaginalis and that these genes were also present in T. tenax, albeit at very low levels of expression. Conclusion These results suggest that T. vaginalis and T. tenax have remarkable genetic identity and that T. vaginalis has higher levels of gene expression when compared to that of T. tenax. The data may suggest that T. tenax could be a variant of T. vaginalis.

Coordinate gene regulation by fimbriae-induced signal transduction

DEFF Research Database (Denmark)

Schembri, Mark; Klemm, Per

2001-01-01

whether fimbriae expression can affect expression of other genes, Analysis of gene expression in two E.coli strains, differing in the fim locus, indicated the flu gene to be affected. The flu gene encodes the antigen 43 (Ag43) surface protein, specifically involved in bacterial aggregation...

Construction of a recombinant adenovirus co-expressing truncated human prostate-specific membrane antigen and mouse 4-1BBL genes and its effect on dendritic cells

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Xiaodong Weng

2011-03-01

Full Text Available Our aim was to construct a recombinant adenovirus co-expressing truncated human prostate-specific membrane antigen (tPSMA and mouse 4-1BBL genes and to determine its effect on dendritic cells (DCs generated from bone marrow suspensions harvested from C57BL/6 mice for which the effect of 4-1BBL on DCs is not clear, especially during DCs processing tumor-associated antigen. Replication deficient adenovirus AdMaxTM Expression System was used to construct recombinant adenovirus Ad-tPSMA-internal ribosome entry site-mouse 4-1BBL (Ad-tPSMA-IRES-m4-1BBL and Ad-enhanced green fluorescent protein. Day 7 proliferating DC aggregates generated from C57BL/6 mice were collected as immature DCs and further mature DCs were obtained by lipopolysaccharide activated immature DCs. After DCs were exposed to the recombinant adenovirus with 250 multiplicity of infection, the expression of tPSMA and m4-1BBL proteins were detected by Western blot, and the apoptosis and phenotype of DCs were analyzed by flow cytometry. Cytokines (IL-6 and IL-12 in the supernatant were detected by enzyme-linked immunosorbent assay (ELISA. Proliferation of T cells was detected by allogeneic mixed lymphocyte reactions. The tPSMA and m4-1BBL proteins were expressed correctly. The apoptosis rate of DCs transfected with Ad-tPSMA-IRES-m4-1BBL was 14.6%, lower than that of control DCs. The expression of co-stimulatory molecules [CD80 (81.6 ± 5.4% and CD86 (80.13 ± 2.81%] up-regulated in Ad-tPSMA-IRES-m4-1BBL-pulsed DCs, and the level of IL-6 (3960.2 ± 50.54 pg/mL and IL-12 (249.57 ± 12.51 pg/mL production in Ad-tPSMA-IRES-m4-1BBL-transduced DCs were significantly higher (P < 0.05 than those in control DCs. Ad-tPSMA-IRES-m4-1BBL induced higher T-cell proliferation (OD450 = 0.614 ± 0.018, indicating that this recombinant adenovirus can effectively enhance the activity of DCs.

Expression of the Gastrin-Releasing Peptide Receptor, the Prostate Stem Cell Antigen and the Prostate-Specific Membrane Antigen in Lymph Node and Bone Metastases of Prostate Cancer

NARCIS (Netherlands)

Ananias, Hildo J. K.; van den Heuvel, Marius C.; Helfrich, Wijnand; de Jong, Igle J.

2009-01-01

OBJECTIVE. Cell membrane antigens like the gastrin-releasing peptide receptor (GRPR), the prostate stem cell antigen (PSCA), and the prostate-specific membrane antigen (PSMA), expressed in prostate cancer, are attractive targets for new therapeutic and diagnostic applications. Therefore, we

The effects of a partitioned var gene repertoire of Plasmodium falciparum on antigenic diversity and the acquisition of clinical immunity

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Arinaminpathy Nimalan

2008-01-01

Full Text Available Abstract Background The human malaria parasite Plasmodium falciparum exploits antigenic diversity and within-host antigenic variation to evade the host's immune system. Of particular importance are the highly polymorphic var genes that encode the family of cell surface antigens PfEMP1 (Plasmodium falciparum Erythrocyte Membrane Protein 1. It has recently been shown that in spite of their extreme diversity, however, these genes fall into distinct groups according to chromosomal location or sequence similarity, and that recombination may be confined within these groups. Methods This study presents a mathematical analysis of how recombination hierarchies affect diversity, and, by using simple stochastic simulations, investigates how intra- and inter-genic diversity influence the rate at which individuals acquire clinical immunity. Results The analysis demonstrates that the partitioning of the var gene repertoire has a limiting effect on the total diversity attainable through recombination and that the limiting effect is strongly influenced by the respective sizes of each of the partitions. Furthermore, by associating expression of one of the groups with severe malaria it is demonstrated how a small number of infections can be sufficient to protect against disease despite a seemingly limitless number of possible non-identical repertoires. Conclusion Recombination hierarchies within the var gene repertoire of P. falciparum have a severe effect on strain diversity and the process of acquiring immunity against clinical malaria. Future studies will show how the existence of these recombining groups can offer an evolutionary advantage in spite of their restriction on diversity.

The evaluaton of prevalence rate of p53 antigen expression in cutaneous malignant melanoma and it′s relation to tumor thickness

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Faghihi Gita

2005-01-01

Full Text Available P53 tumor suppressor gene mutation is one of the most common genetic alteration in human malignancies. This study was done to determine the prevalence of the P53 antigen expression by sex, age, type of melanoma, thickness of the lesion and site of the antigen expression either cytoplasmic or nuclear. Paraffin embeded block of 50 patients (45 primary and metastaticwith documented diagnosis of melanoma deparaffinized and immuno stained with DO-7 monoclonal antibody. The lesions were divided depending on the degree of the staining as follow: 1. no staining, 2. mild (less than 10%, 3. moderate (10%-50% staining, 4. severe (more than 50%. Fifty four percent of evaluated patients were female and 46% were male. Forty percent of lesions were graded as no staining, 36% of lesions showed mild staining, 14% moderate and 10% severe staining site of expression was excusively in the cytoplasm. There was no meaningful statistical deference between severity of staining and the age group, sex, type and thickness of melanoma. (p value was 0.532, 0.488, 0.626, 0.954 respectively.

Profiling helper T cell subset gene expression in deer mice

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Hjelle Brian

2006-08-01

Full Text Available Abstract Background Deer mice (Peromyscus maniculatus are the most common mammals in North America and are reservoirs for several zoonotic agents, including Sin Nombre virus (SNV, the principal etiologic agent of hantavirus cardiopulmonary syndrome (HCPS in North America. Unlike human HCPS patients, SNV-infected deer mice show no overt pathological symptoms, despite the presence of virus in the lungs. A neutralizing IgG antibody response occurs, but the virus establishes a persistent infection. Limitations of detailed analysis of deer mouse immune responses to SNV are the lack of reagents and methods for evaluating such responses. Results We developed real-time PCR-based detection assays for several immune-related transcription factor and cytokine genes from deer mice that permit the profiling of CD4+ helper T cells, including markers of Th1 cells (T-bet, STAT4, IFNγ, TNF, LT, Th2 cells (GATA-3, STAT6, IL-4, IL-5 and regulatory T cells (Fox-p3, IL-10, TGFβ1. These assays compare the expression of in vitro antigen-stimulated and unstimulated T cells from individual deer mice. Conclusion We developed molecular methods for profiling immune gene expression in deer mice, including a multiplexed real-time PCR assay for assessing expression of several cytokine and transcription factor genes. These assays should be useful for characterizing the immune responses of experimentally- and naturally-infected deer mice.

Application of Adoptive T-Cell Therapy Using Tumor Antigen-Specific T-Cell Receptor Gene Transfer for the Treatment of Human Leukemia

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Toshiki Ochi

2010-01-01

Full Text Available The last decade has seen great strides in the field of cancer immunotherapy, especially the treatment of melanoma. Beginning with the identification of cancer antigens, followed by the clinical application of anti-cancer peptide vaccination, it has now been proven that adoptive T-cell therapy (ACT using cancer antigen-specific T cells is the most effective option. Despite the apparent clinical efficacy of ACT, the timely preparation of a sufficient number of cancer antigen-specific T cells for each patient has been recognized as its biggest limitation. Currently, therefore, attention is being focused on ACT with engineered T cells produced using cancer antigen-specific T-cell receptor (TCR gene transfer. With regard to human leukemia, ACT using engineered T cells bearing the leukemia antigen-specific TCR gene still remains in its infancy. However, several reports have provided preclinical data on TCR gene transfer using Wilms' tumor gene product 1 (WT1, and also preclinical and clinical data on TCR gene transfer involving minor histocompatibility antigen, both of which have been suggested to provide additional clinical benefit. In this review, we examine the current status of anti-leukemia ACT with engineered T cells carrying the leukemia antigen-specific TCR gene, and discuss the existing barriers to progress in this area.

Cytotoxic T cells in chronic idiopathic neutropenia express restricted antigen receptors.

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Mastrodemou, Semeli; Stalika, Evangelia; Vardi, Anna; Gemenetzi, Katerina; Spanoudakis, Michalis; Karypidou, Maria; Mavroudi, Irene; Hadzidimitriou, Anastasia; Stavropoulos-Giokas, Catherine; Papadaki, Helen A; Stamatopoulos, Kostas

2017-12-01

Chronic idiopathic neutropenia (CIN) is an acquired disorder of granulopoiesis characterized by female predominance and mostly uncomplicated course. Crucial to CIN pathophysiology is the presence of activated T lymphocytes with myelosuppressive properties in both peripheral blood (PB) and bone marrow (BM). We systematically profiled the T cell receptor beta chain (TRB) gene repertoire in CD8 + cells of 34 CIN patients through subcloning/Sanger sequencing analysis of TRBV-TRBD-TRBJ gene rearrangements. Remarkable repertoire skewing and oligoclonality were observed, along with shared clonotypes between different patients, alluding to antigen selection. Cross-comparison of our sequence dataset with public TRB sequence databases revealed that CIN may rarely share common immunogenetic features with other entities, however, the CIN TRB repertoire is largely disease-biased. Overall, these findings suggest that CIN may be driven by long-term exposure to a restricted set of specific CIN-associated antigens.

Phasevarions mediate random switching of gene expression in pathogenic Neisseria.

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Yogitha N Srikhanta

2009-04-01

Full Text Available Many host-adapted bacterial pathogens contain DNA methyltransferases (mod genes that are subject to phase-variable expression (high-frequency reversible ON/OFF switching of gene expression. In Haemophilus influenzae, the random switching of the modA gene controls expression of a phase-variable regulon of genes (a "phasevarion", via differential methylation of the genome in the modA ON and OFF states. Phase-variable mod genes are also present in Neisseria meningitidis and Neisseria gonorrhoeae, suggesting that phasevarions may occur in these important human pathogens. Phylogenetic studies on phase-variable mod genes associated with type III restriction modification (R-M systems revealed that these organisms have two distinct mod genes--modA and modB. There are also distinct alleles of modA (abundant: modA11, 12, 13; minor: modA4, 15, 18 and modB (modB1, 2. These alleles differ only in their DNA recognition domain. ModA11 was only found in N. meningitidis and modA13 only in N. gonorrhoeae. The recognition site for the modA13 methyltransferase in N. gonorrhoeae strain FA1090 was identified as 5'-AGAAA-3'. Mutant strains lacking the modA11, 12 or 13 genes were made in N. meningitidis and N. gonorrhoeae and their phenotype analyzed in comparison to a corresponding mod ON wild-type strain. Microarray analysis revealed that in all three modA alleles multiple genes were either upregulated or downregulated, some of which were virulence-associated. For example, in N. meningitidis MC58 (modA11, differentially expressed genes included those encoding the candidate vaccine antigens lactoferrin binding proteins A and B. Functional studies using N. gonorrhoeae FA1090 and the clinical isolate O1G1370 confirmed that modA13 ON and OFF strains have distinct phenotypes in antimicrobial resistance, in a primary human cervical epithelial cell model of infection, and in biofilm formation. This study, in conjunction with our previous work in H. influenzae, indicates

Phasevarions mediate random switching of gene expression in pathogenic Neisseria.

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Srikhanta, Yogitha N; Dowideit, Stefanie J; Edwards, Jennifer L; Falsetta, Megan L; Wu, Hsing-Ju; Harrison, Odile B; Fox, Kate L; Seib, Kate L; Maguire, Tina L; Wang, Andrew H-J; Maiden, Martin C; Grimmond, Sean M; Apicella, Michael A; Jennings, Michael P

2009-04-01

Many host-adapted bacterial pathogens contain DNA methyltransferases (mod genes) that are subject to phase-variable expression (high-frequency reversible ON/OFF switching of gene expression). In Haemophilus influenzae, the random switching of the modA gene controls expression of a phase-variable regulon of genes (a "phasevarion"), via differential methylation of the genome in the modA ON and OFF states. Phase-variable mod genes are also present in Neisseria meningitidis and Neisseria gonorrhoeae, suggesting that phasevarions may occur in these important human pathogens. Phylogenetic studies on phase-variable mod genes associated with type III restriction modification (R-M) systems revealed that these organisms have two distinct mod genes--modA and modB. There are also distinct alleles of modA (abundant: modA11, 12, 13; minor: modA4, 15, 18) and modB (modB1, 2). These alleles differ only in their DNA recognition domain. ModA11 was only found in N. meningitidis and modA13 only in N. gonorrhoeae. The recognition site for the modA13 methyltransferase in N. gonorrhoeae strain FA1090 was identified as 5'-AGAAA-3'. Mutant strains lacking the modA11, 12 or 13 genes were made in N. meningitidis and N. gonorrhoeae and their phenotype analyzed in comparison to a corresponding mod ON wild-type strain. Microarray analysis revealed that in all three modA alleles multiple genes were either upregulated or downregulated, some of which were virulence-associated. For example, in N. meningitidis MC58 (modA11), differentially expressed genes included those encoding the candidate vaccine antigens lactoferrin binding proteins A and B. Functional studies using N. gonorrhoeae FA1090 and the clinical isolate O1G1370 confirmed that modA13 ON and OFF strains have distinct phenotypes in antimicrobial resistance, in a primary human cervical epithelial cell model of infection, and in biofilm formation. This study, in conjunction with our previous work in H. influenzae, indicates that

FARO server: Meta-analysis of gene expression by matching gene expression signatures to a compendium of public gene expression data

DEFF Research Database (Denmark)

Manijak, Mieszko P.; Nielsen, Henrik Bjørn

2011-01-01

circumvented by instead matching gene expression signatures to signatures of other experiments. FINDINGS: To facilitate this we present the Functional Association Response by Overlap (FARO) server, that match input signatures to a compendium of 242 gene expression signatures, extracted from more than 1700...... Arabidopsis microarray experiments. CONCLUSIONS: Hereby we present a publicly available tool for robust characterization of Arabidopsis gene expression experiments which can point to similar experimental factors in other experiments. The server is available at http://www.cbs.dtu.dk/services/faro/....

Digital gene expression analysis of gene expression differences within Brassica diploids and allopolyploids.

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Jiang, Jinjin; Wang, Yue; Zhu, Bao; Fang, Tingting; Fang, Yujie; Wang, Youping

2015-01-27

Brassica includes many successfully cultivated crop species of polyploid origin, either by ancestral genome triplication or by hybridization between two diploid progenitors, displaying complex repetitive sequences and transposons. The U's triangle, which consists of three diploids and three amphidiploids, is optimal for the analysis of complicated genomes after polyploidization. Next-generation sequencing enables the transcriptome profiling of polyploids on a global scale. We examined the gene expression patterns of three diploids (Brassica rapa, B. nigra, and B. oleracea) and three amphidiploids (B. napus, B. juncea, and B. carinata) via digital gene expression analysis. In total, the libraries generated between 5.7 and 6.1 million raw reads, and the clean tags of each library were mapped to 18547-21995 genes of B. rapa genome. The unambiguous tag-mapped genes in the libraries were compared. Moreover, the majority of differentially expressed genes (DEGs) were explored among diploids as well as between diploids and amphidiploids. Gene ontological analysis was performed to functionally categorize these DEGs into different classes. The Kyoto Encyclopedia of Genes and Genomes analysis was performed to assign these DEGs into approximately 120 pathways, among which the metabolic pathway, biosynthesis of secondary metabolites, and peroxisomal pathway were enriched. The non-additive genes in Brassica amphidiploids were analyzed, and the results indicated that orthologous genes in polyploids are frequently expressed in a non-additive pattern. Methyltransferase genes showed differential expression pattern in Brassica species. Our results provided an understanding of the transcriptome complexity of natural Brassica species. The gene expression changes in diploids and allopolyploids may help elucidate the morphological and physiological differences among Brassica species.

Diagnostic value of tolerance-related gene expression measured in the recipient alloantigen-reactive T cell fraction.

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Lim, Dong-Gyun; Park, Youn-Hee; Kim, Sung-Eun; Jeong, Seong-Hee; Kim, Song-Cheol

2013-08-01

The efficient development of tolerance-inducing therapies and safe reduction of immunosuppression should be supported by early diagnosis and prediction of tolerance in transplantation. Using mouse models of donor-specific tolerance to allogeneic skin and islet grafts we tested whether measurement of tolerance-related gene expression in their alloantigen-reactive peripheral T cell fraction efficiently reflected the tolerance status of recipients. We found that Foxp3, Nrn1, and Klrg1 were preferentially expressed in conditions of tolerance compared with rejection or unmanipulated controls if their expression is measured in CD69(+) T cells prepared from coculture of recipient peripheral T cells and donor antigen-presenting cells. The same pattern of gene expression was observed in recipients grafted with either skin or islets, recipients of different genetic origins, and even those taking immunosuppressive drugs. These findings suggest that the expression of tolerance-related genes in the alloantigen-reactive T cell fraction could be used to detect tolerance in the clinic. Copyright © 2013 Elsevier Inc. All rights reserved.

Limited transplantation of antigen-expressing hematopoietic stem cells induces long-lasting cytotoxic T cell responses.

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Warren L Denning

2011-02-01

Full Text Available Harnessing the ability of cytotoxic T lymphocytes (CTLs to recognize and eradicate tumor or pathogen-infected cells is a critical goal of modern immune-based therapies. Although multiple immunization strategies efficiently induce high levels of antigen-specific CTLs, the initial increase is typically followed by a rapid contraction phase resulting in a sharp decline in the frequency of functional CTLs. We describe a novel approach to immunotherapy based on a transplantation of low numbers of antigen-expressing hematopoietic stem cells (HSCs following nonmyeloablative or partially myeloablative conditioning. Continuous antigen presentation by a limited number of differentiated transgenic hematopoietic cells results in an induction and prolonged maintenance of fully functional effector T cell responses in a mouse model. Recipient animals display high levels of antigen-specific CTLs four months following transplantation in contrast to dendritic cell-immunized animals in which the response typically declines at 4-6 weeks post-immunization. Majority of HSC-induced antigen-specific CD8+ T cells display central memory phenotype, efficiently kill target cells in vivo, and protect recipients against tumor growth in a preventive setting. Furthermore, we confirm previously published observation that high level engraftment of antigen-expressing HSCs following myeloablative conditioning results in tolerance and an absence of specific cytotoxic activity in vivo. In conclusion, the data presented here supports potential application of immunization by limited transplantation of antigen-expressing HSCs for the prevention and treatment of cancer and therapeutic immunization of chronic infectious diseases such as HIV-1/AIDS.

Development of stable Vibrio cholerae O1 Hikojima type vaccine strains co-expressing the Inaba and Ogawa lipopolysaccharide antigens.

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Stefan L Karlsson

Full Text Available We describe here the development of stable classical and El Tor V. cholerae O1 strains of the Hikojima serotype that co-express the Inaba and Ogawa antigens of O1 lipopolysaccharide (LPS. Mutation of the wbeT gene reduced LPS perosamine methylation and thereby gave only partial transformation into Ogawa LPS on the cell surface. The strains express approximately equal amounts of Inaba- and Ogawa-LPS antigens which are preserved after formalin-inactivation of the bacteria. Oral immunizations of both inbred and outbred mice with formalin-inactivated whole-cell vaccine preparations of these strains elicited strong intestinal IgA anti-LPS as well as serum vibriocidal antibody responses against both Inaba and Ogawa that were fully comparable to the responses induced by the licensed Dukoral vaccine. Passive protection studies in infant mice showed that immune sera raised against either of the novel Hikojima vaccine strains protected baby mice against infection with virulent strains of both serotypes. This study illustrates the power of using genetic manipulation to improve the properties of bacteria strains for use in killed whole-cell vaccines.

Detection of Burkholderia pseudomallei O-antigen serotypes in near-neighbor species

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Stone Joshua K

2012-11-01

Full Text Available Abstract Background Burkholderia pseudomallei is the etiological agent of melioidosis and a CDC category B select agent with no available effective vaccine. Previous immunizations in mice have utilized the lipopolysaccharide (LPS as a potential vaccine target because it is known as one of the most important antigenic epitopes in B. pseudomallei. Complicating this strategy are the four different B. pseudomallei LPS O-antigen types: A, B, B2, and rough. Sero-crossreactivity is common among O-antigens of Burkholderia species. Here, we identified the presence of multiple B. pseudomallei O-antigen types and sero-crossreactivity in its near-neighbor species. Results PCR screening of O-antigen biosynthesis genes, phenotypic characterization using SDS-PAGE, and immunoblot analysis showed that majority of B. mallei and B. thailandensis strains contained the typical O-antigen type A. In contrast, most of B. ubonensis and B. thailandensis-like strains expressed the atypical O-antigen types B and B2, respectively. Most B. oklahomensis strains expressed a distinct and non-seroreactive O-antigen type, except strain E0147 which expressed O-antigen type A. O-antigen type B2 was also detected in B. thailandensis 82172, B. ubonensis MSMB108, and Burkholderia sp. MSMB175. Interestingly, B. thailandensis-like MSMB43 contained a novel serotype B positive O-antigen. Conclusions This study expands the number of species which express B. pseudomallei O-antigen types. Further work is required to elucidate the full structures and how closely these are to the B. pseudomallei O-antigens, which will ultimately determine the efficacy of the near-neighbor B serotypes for vaccine development.

Evaluation of Antigen-Conjugated Fluorescent Beads to Identify Antigen-Specific B Cells

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Isabel Correa

2018-03-01

Full Text Available Selection of single antigen-specific B cells to identify their expressed antibodies is of considerable interest for evaluating human immune responses. Here, we present a method to identify single antibody-expressing cells using antigen-conjugated fluorescent beads. To establish this, we selected Folate Receptor alpha (FRα as a model antigen and a mouse B cell line, expressing both the soluble and the membrane-bound forms of a human/mouse chimeric antibody (MOv18 IgG1 specific for FRα, as test antibody-expressing cells. Beads were conjugated to FRα using streptavidin/avidin-biotin bridges and used to select single cells expressing the membrane-bound form of anti-FRα. Bead-bound cells were single cell-sorted and processed for single cell RNA retrotranscription and PCR to isolate antibody heavy and light chain variable regions. Variable regions were then cloned and expressed as human IgG1/k antibodies. Like the original clone, engineered antibodies from single cells recognized native FRα. To evaluate whether antigen-coated beads could identify specific antibody-expressing cells in mixed immune cell populations, human peripheral blood mononuclear cells (PBMCs were spiked with test antibody-expressing cells. Antigen-specific cells could comprise up to 75% of cells selected with antigen-conjugated beads when the frequency of the antigen-positive cells was 1:100 or higher. In PBMC pools, beads conjugated to recombinant antigens FRα and HER2 bound antigen-specific anti-FRα MOv18 and anti-HER2 Trastuzumab antibody-expressing cells, respectively. From melanoma patient-derived B cells selected with melanoma cell line-derived protein-coated fluorescent beads, we generated a monoclonal antibody that recognized melanoma antigen-coated beads. This approach may be further developed to facilitate analysis of B cells and their antibody profiles at the single cell level and to help unravel humoral immune repertoires.

Evaluation of Antigen-Conjugated Fluorescent Beads to Identify Antigen-Specific B Cells.

Science.gov (United States)

Correa, Isabel; Ilieva, Kristina M; Crescioli, Silvia; Lombardi, Sara; Figini, Mariangela; Cheung, Anthony; Spicer, James F; Tutt, Andrew N J; Nestle, Frank O; Karagiannis, Panagiotis; Lacy, Katie E; Karagiannis, Sophia N

2018-01-01

Selection of single antigen-specific B cells to identify their expressed antibodies is of considerable interest for evaluating human immune responses. Here, we present a method to identify single antibody-expressing cells using antigen-conjugated fluorescent beads. To establish this, we selected Folate Receptor alpha (FRα) as a model antigen and a mouse B cell line, expressing both the soluble and the membrane-bound forms of a human/mouse chimeric antibody (MOv18 IgG1) specific for FRα, as test antibody-expressing cells. Beads were conjugated to FRα using streptavidin/avidin-biotin bridges and used to select single cells expressing the membrane-bound form of anti-FRα. Bead-bound cells were single cell-sorted and processed for single cell RNA retrotranscription and PCR to isolate antibody heavy and light chain variable regions. Variable regions were then cloned and expressed as human IgG1/k antibodies. Like the original clone, engineered antibodies from single cells recognized native FRα. To evaluate whether antigen-coated beads could identify specific antibody-expressing cells in mixed immune cell populations, human peripheral blood mononuclear cells (PBMCs) were spiked with test antibody-expressing cells. Antigen-specific cells could comprise up to 75% of cells selected with antigen-conjugated beads when the frequency of the antigen-positive cells was 1:100 or higher. In PBMC pools, beads conjugated to recombinant antigens FRα and HER2 bound antigen-specific anti-FRα MOv18 and anti-HER2 Trastuzumab antibody-expressing cells, respectively. From melanoma patient-derived B cells selected with melanoma cell line-derived protein-coated fluorescent beads, we generated a monoclonal antibody that recognized melanoma antigen-coated beads. This approach may be further developed to facilitate analysis of B cells and their antibody profiles at the single cell level and to help unravel humoral immune repertoires.

Evaluation of Antigen-Conjugated Fluorescent Beads to Identify Antigen-Specific B Cells

Science.gov (United States)

Correa, Isabel; Ilieva, Kristina M.; Crescioli, Silvia; Lombardi, Sara; Figini, Mariangela; Cheung, Anthony; Spicer, James F.; Tutt, Andrew N. J.; Nestle, Frank O.; Karagiannis, Panagiotis; Lacy, Katie E.; Karagiannis, Sophia N.

2018-01-01

Selection of single antigen-specific B cells to identify their expressed antibodies is of considerable interest for evaluating human immune responses. Here, we present a method to identify single antibody-expressing cells using antigen-conjugated fluorescent beads. To establish this, we selected Folate Receptor alpha (FRα) as a model antigen and a mouse B cell line, expressing both the soluble and the membrane-bound forms of a human/mouse chimeric antibody (MOv18 IgG1) specific for FRα, as test antibody-expressing cells. Beads were conjugated to FRα using streptavidin/avidin-biotin bridges and used to select single cells expressing the membrane-bound form of anti-FRα. Bead-bound cells were single cell-sorted and processed for single cell RNA retrotranscription and PCR to isolate antibody heavy and light chain variable regions. Variable regions were then cloned and expressed as human IgG1/k antibodies. Like the original clone, engineered antibodies from single cells recognized native FRα. To evaluate whether antigen-coated beads could identify specific antibody-expressing cells in mixed immune cell populations, human peripheral blood mononuclear cells (PBMCs) were spiked with test antibody-expressing cells. Antigen-specific cells could comprise up to 75% of cells selected with antigen-conjugated beads when the frequency of the antigen-positive cells was 1:100 or higher. In PBMC pools, beads conjugated to recombinant antigens FRα and HER2 bound antigen-specific anti-FRα MOv18 and anti-HER2 Trastuzumab antibody-expressing cells, respectively. From melanoma patient-derived B cells selected with melanoma cell line-derived protein-coated fluorescent beads, we generated a monoclonal antibody that recognized melanoma antigen-coated beads. This approach may be further developed to facilitate analysis of B cells and their antibody profiles at the single cell level and to help unravel humoral immune repertoires. PMID:29628923

Extracellular Expression in Aspergillus niger of an Antibody Fused to Leishmania sp. Antigens.

Science.gov (United States)

Magaña-Ortíz, Denis; Fernández, Francisco; Loske, Achim M; Gómez-Lim, Miguel A

2018-01-01

Nucleoside hydrolase and sterol 24-c-methyltransferase, two antigenic proteins of Leishmania sp., were expressed in Aspergillus niger. Genetic transformation of conidia was achieved using underwater shock waves. scFv antibody addressed to DEC205, a receptor of dendritic cells, was fused to two proteins of Leishmania sp. Receptor 205 has a relevant role in the immune system in mammals; it can modulate T cell response to different antigens. Extracellular expression strategy of recombinant antibody was achieved using a fragment of native glucoamylase A (514 aa) as a carrier. Fermentations in shake flasks showed that the recombinant protein (104 kDa) was expressed and secreted only when maltose was used as carbon source; on the contrary, the expression was highly repressed in presence of xylose. Noteworthy, recombinant protein was secreted without glucoamylase-carrier and accumulation at intracellular level was not observed. The results presented here demonstrate the high value of Aspergillus niger as biotechnological platform for recombinant antibodies against Leishmania sp. at low cost. To the best of our knowledge, this is the first report about the recombinant expression of antigenic proteins of Leishmania sp. in filamentous fungi. The protein obtained can be used to explore novel strategies to induce immunity against Leishmania sp. or it can be employed in diagnostic kits to detect this neglected disease.

The Many Faces of Human Leukocyte Antigen-G

DEFF Research Database (Denmark)

Dahl, Mette; Djurisic, Snezana; Hviid, Thomas Vauvert F

2014-01-01

Pregnancy is an immunological paradox, where fetal antigens encoded by polymorphic genes inherited from the father do not provoke a maternal immune response. The fetus is not rejected as it would be theorized according to principles of tissue transplantation. A major contribution to fetal tolerance...... is the human leukocyte antigen (HLA)-G, a nonclassical HLA protein displaying limited polymorphism, restricted tissue distribution, and a unique alternative splice pattern. HLA-G is primarily expressed in placenta and plays multifaceted roles during pregnancy, both as a soluble and a membrane-bound molecule......, differences in HLA-G isoform expression, and possible differences in functional activity. Furthermore, we highlight important observations regarding HLA-G genetics and expression in preeclampsia that future research should address....

[Neoretinal antigen expression: a comparison of anatomical and clinical features of a murine uveoretinitis model].

Science.gov (United States)

Terrada, C; Pâques, M; Fisson, S; De Kozak, Y; Klatzmann, D; Salomon, B; LeHoang, P; Bodaghi, B

2008-02-01

Uveitis is an inflammation involving the retina. The antigens targeted by the experimental models are located in the pigmentary epithelium-photoreceptor complex. To gain insights into the variations in topographic expression of the antigen in the retina, we studied a new mouse model. and methods: Stable retinal expression of the influenza virus hemagglutinin (HA) was obtained after intravitreal or subretinal injection of recombinant adeno-associated virus carrying HA (AAV-HA). One month later, we transferred HA-specific T cells, followed by a subcutaneous immunization of the cognate antigen emulsified in CFA. The animals were clinically examined with a slit lamp biomicroscope. Infiltration of donor cells was detected by immunostaining on retina flatmounts with anti-Thy-1.1 antibody, and infiltrating cells were studied using FACS analysis. Whatever the location of the HA expression, intraocular inflammation was clinically and histologically detected in all animals, between 10 and 15 days after immunization with HA. Lesions were identified with histopathological analysis. The ocular infiltrate was mostly composed of macrophages and HA-specific T cells in different proportions. The topographic variations of targeted ocular antigens do not seem to modify the development of inflammatory reactions in our model. By targeting different antigen-presenting cells, ocular infiltrating cells are different.

Analysis of GAGE, NY-ESO-1 and SP17 cancer/testis antigen expression in early stage non-small cell lung carcinoma

International Nuclear Information System (INIS)

Gjerstorff, Morten F; Pøhl, Mette; Olsen, Karen E; Ditzel, Henrik J

2013-01-01

The unique expression pattern and immunogenic properties of cancer/testis antigens make them ideal targets for immunotherapy of cancer. The MAGE-A3 cancer/testis antigen is frequently expressed in non-small cell lung cancer (NSCLC) and vaccination with MAGE-A3 in patients with MAGE-A3-positive NSCLC has shown promising results. However, little is known about the expression of other cancer/testis antigens in NSCLC. In the present study the expression of cancer/testis antigens GAGE, NY-ESO-1 and SP17 was investigated in patients with completely resected, early stage, primary NSCLC. Tumor biopsies from normal lung tissue and from a large cohort (n = 169) of NSCLC patients were examined for GAGE, NY-ESO-1 and SP17 protein expression by immunohistochemical analysis. The expression of these antigens was further matched to clinical and pathological features using univariate cox regression analysis. GAGE and NY-ESO-1 cancer/testis antigens were not expressed in normal lung tissue, while SP17 was expressed in ciliated lung epithelia. The frequency of GAGE, NY-ESO-1 and SP17 expression in NSCLC tumors were 26.0% (44/169), 11.8% (20/169) and 4.7% (8/169), respectively, and 33.1% (56/169) of the tumors expressed at least one of these antigens. In general, the expression of GAGE, NY-ESO-1 and SP17 was not significantly associated with a specific histotype (adenocarcinoma vs. squamous cell carcinoma), but high-level GAGE expression (>50%) was more frequent in squamous cell carcinoma (p = 0.02). Furthermore, the frequency of GAGE expression was demonstrated to be significantly higher in stage II-IIIa than stage I NSCLC (17.0% vs. 35.8%; p = 0.02). Analysis of the relation between tumor expression of GAGE and NY-ESO-1 and survival endpoints revealed no significant associations. Our study demonstrates that GAGE, NY-ESO-1 and SP17 cancer/testis antigens are candidate targets for immunotherapy of NSCLC and further suggest that multi-antigen vaccines may be beneficial

Quantitative RT-PCR analysis of estrogen receptor gene expression in laser microdissected prostate cancer tissue.

Science.gov (United States)

Walton, Thomas J; Li, Geng; McCulloch, Thomas A; Seth, Rashmi; Powe, Desmond G; Bishop, Michael C; Rees, Robert C

2009-06-01

Real-time quantitative RT-PCR analysis of laser microdissected tissue is considered the most accurate technique for determining tissue gene expression. The discovery of estrogen receptor beta (ERbeta) has focussed renewed interest on the role of estrogen receptors in prostate cancer, yet few studies have utilized the technique to analyze estrogen receptor gene expression in prostate cancer. Fresh tissue was obtained from 11 radical prostatectomy specimens and from 6 patients with benign prostate hyperplasia. Pure populations of benign and malignant prostate epithelium were laser microdissected, followed by RNA isolation and electrophoresis. Quantitative RT-PCR was performed using primers for androgen receptor (AR), estrogen receptor beta (ERbeta), estrogen receptor alpha (ERalpha), progesterone receptor (PGR) and prostate specific antigen (PSA), with normalization to two housekeeping genes. Differences in gene expression were analyzed using the Mann-Whitney U-test. Correlation coefficients were analyzed using Spearman's test. Significant positive correlations were seen when AR and AR-dependent PSA, and ERalpha and ERalpha-dependent PGR were compared, indicating a representative population of RNA transcripts. ERbeta gene expression was significantly over-expressed in the cancer group compared with benign controls (P cancer group (P prostate cancer specimens. In concert with recent studies the findings suggest differential production of ERbeta splice variants, which may play important roles in the genesis of prostate cancer. (c) 2009 Wiley-Liss, Inc.

Three gene expression vector sets for concurrently expressing multiple genes in Saccharomyces cerevisiae.

Science.gov (United States)

Ishii, Jun; Kondo, Takashi; Makino, Harumi; Ogura, Akira; Matsuda, Fumio; Kondo, Akihiko

2014-05-01

Yeast has the potential to be used in bulk-scale fermentative production of fuels and chemicals due to its tolerance for low pH and robustness for autolysis. However, expression of multiple external genes in one host yeast strain is considerably labor-intensive due to the lack of polycistronic transcription. To promote the metabolic engineering of yeast, we generated systematic and convenient genetic engineering tools to express multiple genes in Saccharomyces cerevisiae. We constructed a series of multi-copy and integration vector sets for concurrently expressing two or three genes in S. cerevisiae by embedding three classical promoters. The comparative expression capabilities of the constructed vectors were monitored with green fluorescent protein, and the concurrent expression of genes was monitored with three different fluorescent proteins. Our multiple gene expression tool will be helpful to the advanced construction of genetically engineered yeast strains in a variety of research fields other than metabolic engineering. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

Non-MHC Antigenic Targets of the Humoral Immune Response in Transplantation

OpenAIRE

Zhang, Qiuheng; Reed, Elaine F.

2010-01-01

There is a growing body of data supporting a role for non-HLA antibodies in acute and chronic rejection of solid organ transplants. While many of these non-HLA antigens remain poorly defined, the principle antigenic targets are expressed on cells of the allograft including endothelium and epithelium. These non-HLA antigens are classified as either alloantigens, such as the major histocompatibility complex class I chain-related gene A (MICA) or MICB, or tissue-specific autoantigens such as vim...

Identification, expression and phylogenetic analysis of EgG1Y162 from Echinococcus granulosus

Science.gov (United States)

Zhang, Fengbo; Ma, Xiumin; Zhu, Yuejie; Wang, Hongying; Liu, Xianfei; Zhu, Min; Ma, Haimei; Wen, Hao; Fan, Haining; Ding, Jianbing

2014-01-01

Objective: This study was to clone, identify and analyze the characteristics of egG1Y162 gene from Echinococcus granulosus. Methods: Genomic DNA and total RNAs were extracted from four different developmental stages of protoscolex, germinal layer, adult and egg of Echinococcus granulosus, respectively. Fluorescent quantitative PCR was used for analyzing the expression of egG1Y162 gene. Prokaryotic expression plasmid of pET41a-EgG1Y162 was constructed to express recombinant His-EgG1Y162 antigen. Western blot analysis was performed to detect antigenicity of EgG1Y162 antigen. Gene sequence, amino acid alignment and phylogenetic tree of EgG1Y162 were analyzed by BLAST, online Spidey and MEGA4 software, respectively. Results: EgG1Y162 gene was expressed in four developmental stages of Echinococcus granulosus. And, egG1Y162 gene expression was the highest in the adult stage, with the relative value of 19.526, significantly higher than other three stages. Additionally, Western blot analysis revealed that EgG1Y162 recombinant protein had good reaction with serum samples from Echinococcus granulosus infected human and dog. Moreover, EgG1Y162 antigen was phylogenetically closest to EmY162 antigen, with the similarity over 90%. Conclusion: Our study identified EgG1Y162 antigen in Echinococcus granulosus for the first time. EgG1Y162 antigen had a high similarity with EmY162 antigen, with the genetic differences mainly existing in the intron region. And, EgG1Y162 recombinant protein showed good antigenicity. PMID:25337206

Identification, expression and phylogenetic analysis of EgG1Y162 from Echinococcus granulosus.

Science.gov (United States)

Zhang, Fengbo; Ma, Xiumin; Zhu, Yuejie; Wang, Hongying; Liu, Xianfei; Zhu, Min; Ma, Haimei; Wen, Hao; Fan, Haining; Ding, Jianbing

2014-01-01

This study was to clone, identify and analyze the characteristics of egG1Y162 gene from Echinococcus granulosus. Genomic DNA and total RNAs were extracted from four different developmental stages of protoscolex, germinal layer, adult and egg of Echinococcus granulosus, respectively. Fluorescent quantitative PCR was used for analyzing the expression of egG1Y162 gene. Prokaryotic expression plasmid of pET41a-EgG1Y162 was constructed to express recombinant His-EgG1Y162 antigen. Western blot analysis was performed to detect antigenicity of EgG1Y162 antigen. Gene sequence, amino acid alignment and phylogenetic tree of EgG1Y162 were analyzed by BLAST, online Spidey and MEGA4 software, respectively. EgG1Y162 gene was expressed in four developmental stages of Echinococcus granulosus. And, egG1Y162 gene expression was the highest in the adult stage, with the relative value of 19.526, significantly higher than other three stages. Additionally, Western blot analysis revealed that EgG1Y162 recombinant protein had good reaction with serum samples from Echinococcus granulosus infected human and dog. Moreover, EgG1Y162 antigen was phylogenetically closest to EmY162 antigen, with the similarity over 90%. Our study identified EgG1Y162 antigen in Echinococcus granulosus for the first time. EgG1Y162 antigen had a high similarity with EmY162 antigen, with the genetic differences mainly existing in the intron region. And, EgG1Y162 recombinant protein showed good antigenicity.

Gene expression profiling: cell cycle deregulation and aneuploidy do not cause breast cancer formation in WAP-SVT/t transgenic animals.

Science.gov (United States)

Klein, Andreas; Guhl, Eva; Zollinger, Raphael; Tzeng, Yin-Jeh; Wessel, Ralf; Hummel, Michael; Graessmann, Monika; Graessmann, Adolf

2005-05-01

Microarray studies revealed that as a first hit the SV40 T/t antigen causes deregulation of 462 genes in mammary gland cells (ME cells) of WAP-SVT/t transgenic animals. The majority of deregulated genes are cell proliferation specific and Rb-E2F dependent, causing ME cell proliferation and gland hyperplasia but not breast cancer formation. In the breast tumor cells a further 207 genes are differentially expressed, most of them belonging to the cell communication category. In tissue culture breast tumor cells frequently switch off WAP-SVT/t transgene expression and regain the morphology and growth characteristics of normal ME cells, although the tumor-revertant cells are aneuploid and only 114 genes regain the expression level of normal ME cells. The profile of retransformants shows that only 38 deregulated genes are tumor-specific, and that none of them is considered to be a typical breast cancer gene.

Expression of Tac antigen component of bovine interleukin-2 receptor in different leukocyte populations infected with Theileria parva or Theileria annulata.

Science.gov (United States)

Dobbelaere, D A; Prospero, T D; Roditi, I J; Kelke, C; Baumann, I; Eichhorn, M; Williams, R O; Ahmed, J S; Baldwin, C L; Clevers, H

1990-01-01

The Tac antigen component of the bovine interleukin-2 receptor was expressed as a Cro-beta-galactosidase fusion protein in Escherichia coli and used to raise antibodies in rabbits. These antibodies were used for flow cytofluorimetric analysis to investigate the expression of Tac antigen in a variety of Theileria parva-infected cell lines and also in three Theileria annulata-infected cell lines. Cells expressing Tac antigen on their surface were found in all T. parva-infected cell lines tested whether these were of T- or B-cell origin. T cells expressing Tac antigen could be CD4- CD8-, CD4+ CD8-, CD4- CD8+, or CD4+ CD8+. Tac antigen expression was observed both in cultures which had been maintained in the laboratory for several years and in transformed cell lines which had recently been established by infection of lymphocytes in vitro with T. parva. Northern (RNA) blot analysis demonstrated Tac antigen transcripts in RNA isolated from all T. parva-infected cell lines. Three T. annulata-infected cell lines which were not of T-cell origin were also tested. Two of them expressed Tac antigen on their surface. Abundant Tac antigen mRNA was detected in these T. annulata-infected cell lines, but only trace amounts were demonstrated in the third cell line, which contained very few Tac antigen-expressing cells. In all cell lines tested, whether cloned or uncloned, a proportion of the cells did not express detectable levels of Tac antigen on their surface. This was also the case for a number of other leukocyte surface markers. In addition, we showed that the interleukin-2 receptors were biologically functional, because addition of recombinant interleukin-2 to cultures stimulated cell proliferation. Recombinant interleukin-2 treatment also resulted in increased amounts of steady-state Tac antigen mRNA. The relevance of interleukin-2 receptor expression on Theileria-infected cells is discussed. Images PMID:1979317

Large scale gene expression meta-analysis reveals tissue-specific, sex-biased gene expression in humans

Directory of Open Access Journals (Sweden)

Benjamin Mayne

2016-10-01

Full Text Available The severity and prevalence of many diseases are known to differ between the sexes. Organ specific sex-biased gene expression may underpin these and other sexually dimorphic traits. To further our understanding of sex differences in transcriptional regulation, we performed meta-analyses of sex biased gene expression in multiple human tissues. We analysed 22 publicly available human gene expression microarray data sets including over 2500 samples from 15 different tissues and 9 different organs. Briefly, by using an inverse-variance method we determined the effect size difference of gene expression between males and females. We found the greatest sex differences in gene expression in the brain, specifically in the anterior cingulate cortex, (1818 genes, followed by the heart (375 genes, kidney (224 genes, colon (218 genes and thyroid (163 genes. More interestingly, we found different parts of the brain with varying numbers and identity of sex-biased genes, indicating that specific cortical regions may influence sexually dimorphic traits. The majority of sex-biased genes in other tissues such as the bladder, liver, lungs and pancreas were on the sex chromosomes or involved in sex hormone production. On average in each tissue, 32% of autosomal genes that were expressed in a sex-biased fashion contained androgen or estrogen hormone response elements. Interestingly, across all tissues, we found approximately two-thirds of autosomal genes that were sex-biased were not under direct influence of sex hormones. To our knowledge this is the largest analysis of sex-biased gene expression in human tissues to date. We identified many sex-biased genes that were not under the direct influence of sex chromosome genes or sex hormones. These may provide targets for future development of sex-specific treatments for diseases.

Structural defect linked to nonrandom mutations in the matrix gene of Biden strain subacute sclerosing panencephalitis virus defined by cDNA cloning and expression of chimeric genes

International Nuclear Information System (INIS)

Ayata, M.; Hirano, A.; Wong, T.C.

1989-01-01

Biken strain, a nonproductive measles viruslike agent isolated from a subacute sclerosing panencephalitis (SSPE) patient, contains a posttranscriptional defect affecting matrix (M) protein. A putative M protein was translated in vitro with RNA from Biken strain-infected cells. A similar protein was detected in vivo by an antiserum against a peptide synthesized from the cloned M gene of Edmonston strain measles virus. By using a novel method, full-length cDNAs of the Biken M gene were selectively cloned. The cloned Biken M gene contained an open reading frame which encoded 8 extra carboxy-terminal amino acid residues and 20 amino acid substitutions predicted to affect both the hydrophobicity and secondary structure of the gene product. The cloned gene was expressed in vitro and in vivo into a 37,500 M r protein electrophoretically and antigenically distinct from the M protein of Edmonston strain but identical to the M protein in Biken strain-infected cells. Chimeric M proteins synthesized in vitro and in vivo showed that the mutations in the carboxy-proximal region altered the local antigenicity and those in the amino region affected the overall protein conformation. The protein expressed from the Biken M gene was unstable in vivo. Instability was attributed to multiple mutations. These results offer insights into the basis of the defect in Biken strain and pose intriguing questions about the evolutionary origins of SSPE viruses in general

The effects of Ostertagia occidentalis somatic antigens on ovine TLR2 and TLR4 expression

Directory of Open Access Journals (Sweden)

Hassan BORJI

2015-10-01

Full Text Available Background: Recognition of helminth-derived pathogen associated molecular patterns (PAMPs by pattern recognition receptors (PRRs, including toll like recep­tors (TLRs is the first step towards initiating anti–helminth immune re­sponses.Methods: Using somatic antigens of Ostertagia occidentalis, an important abomasal parasite of ruminants, the expression of ovine TLR2 and TLR4 in peripheral blood mononuclear cells (PBMCs was analyzed by real-time quatitative reverse-transcrip­tion polymerase chain reaction (qRT-PCR. Somatic antigens of O. occidentalis were prepared to stimulate ovine PBMCs in a time and dose dependent manner.Results: A high expression of TLR2 and TLR4 was observed in PBMCs cultured with somatic antigens of the parasites specially when PBMCs were cultured with 100 µg/ml of somatic antigens and incubated for 2h. Up-regulation of TLR2 expres­sion was more pronounced and evident in our study.Conclsusion: Somatic antigens of O. occidentalis have immunostimulatory and domi­nant role on peripheral immune cells. This study provide for the first time evidence of induction of TLRs in ovine PBMCs by somatic antigen of O. occidentalis

[Prokaryotic expression of Leptospira interrogans groEL gene and immunoprotection of its products in hamsters].

Science.gov (United States)

Li, Xiaoyu; Wang, Yinhuan; Yan, Jie; Cheng, Dongqing

2013-03-01

To construct a prokaryotic expression system of groEL gene of Leptospira interrogans serogroup Icterohaemorrhagia serovar Lai strain Lai, and to determine the immunoprotective effect of recombinant GroEL protein (rGroEL) in LVG hamsters. The groEL gene was amplified by high fidelity PCR and the amplification products were then sequenced. A prokaryotic expression system of groEL gene was constructed using routine genetic engineering technique. SDS-PAGE plus Bio-Rad Gel Image Analyzer was applied to examine the expression and dissolubility of rGroEL protein while Ni-NTA affinity chromatography was used to extract the expressed rGroEL. The immunoprotective rate in rGroEL-immunized LVG hamsters was determined after challenge with L.interrogans strain Lai. The cross agglutination titers of sera from immunized hamsters with different L.interrogans serogroups were detected using MAT. The nucleotide and amino acid sequences of the cloned groEL gene were the same as those reported in GenBank. The constructed prokaryotic expression system of groEL gene expressed soluble rGroEL. The immunoprotective rates of 100 and 200 μg rGroEL in LVG hamsters were 50.0 % and 75.0%, respectively. The sera from the rGroEL-immunized LVG hamsters agglutinated all the L.interrogans serogroups tested with different levels. The GroEL protein is a genus-specific immunoprotective antigen of L.interrogans and can be used to develop an universal genetically engineering vaccine of Leptospira.

T cells expressing VHH-directed oligoclonal chimeric HER2 antigen receptors

DEFF Research Database (Denmark)

Jamnani, Fatemeh Rahimi; Rahbarizadeh, Fatemeh; Shokrgozar, Mohammad Ali

2014-01-01

Adoptive cell therapy with engineered T cells expressing chimeric antigen receptors (CARs) originated from antibodies is a promising strategy in cancer immunotherapy. Several unsuccessful trials, however, highlight the need for alternative conventional binding domains and the better combination...

Expression of antigens coded in murine leukemia viruses on thymocytes of allogeneic donor origin in AKR mice following syngeneic or allogeneic bone marrow transplantation

International Nuclear Information System (INIS)

Wustrow, T.P.; Good, R.A.

1985-01-01

Removal of T-lymphocytes from marrow inoculum with monoclonal antibody plus complement permitted establishment of long-lived allogeneic chimeras between C57BL/6 and AKR/J mice. Development of leukemia was prevented for 15 mo. Protection from leukemia occurred with both young (4 wk) and older (4 mo) recipients. AKR mice reconstituted with syngeneic marrow or control AKR mice all developed leukemia-lymphoma before 1 yr of age. During spontaneous lymphomagenesis in AKR mice, amplified expression of gag or env gene-coded virus antigens on the surface of thymocytes preceded leukemia development and evidence for amplification of other virus genes. These changes generally appeared before 6 mo. Similar viral gene expression and viral gene amplification occurred in the thymus and spleen cells of leukemia-resistant chimeric mice. Using monoclonal antibodies to Mr 70,000 glycoprotein epitopes characteristic of ecotropic, xenotropic, or dualtropic viruses, antigens marking each virus form were found on thymocytes of allogeneic 4-wk and 4-mo chimeras as well as on the cells of AKR mice and of AKR mice reconstituted with syngeneic marrow. Flow cytometric analysis showed amplification of the virus genes in mice protected from leukemia-lymphoma by allogeneic bone marrow transplantation from leukemia-resistant mice. Allogeneic chimeras and syngeneically transplanted mice both showed evidence of accelerated viremia and of recombinant virus formation. The findings suggest that an event essential to leukemogenesis which occurs within the AKR lymphoid cells or their environment is lacking in the allogeneic chimeras. The nature of this influence of a resistance gene or genes introduced into AKR mice by allogeneic bone marrow transplantation deserves further study

Genistein-induced alterations of radiation-responsive gene expression

Energy Technology Data Exchange (ETDEWEB)

Grace, M.B. [Armed Forces Radiobiology Research Institute, 8901 Wisconsin Avenue, Bethesda, MD 20889-5603 (United States)], E-mail: grace@afrri.usuhs.mil; Blakely, W.F.; Landauer, M.R. [Armed Forces Radiobiology Research Institute, 8901 Wisconsin Avenue, Bethesda, MD 20889-5603 (United States)

2007-07-15

In order to clarify the molecular mechanism of radioprotection and understand biological dosimetry in the presence of medical countermeasure-radioprotectants, their effects on ionizing radiation (IR)-responsive molecular biomarkers must be examined. We used genistein in a radiation model system and measured gene expression by multiplex QRT-PCR assay in drug-treated healthy human blood cultures. Genistein has been demonstrated to be a radiosensitizer of malignant cells and a radioprotector against IR-induced lethality in a mouse model. Whole-blood cultures were supplemented with 50, 100, and 200{mu}M concentrations of genistein, 16 h prior to receiving a 2-Gy ({sup 60}Co-{gamma} rays, 10 cGy/min) dose of IR. Total RNA was isolated from whole blood 24 h postirradiation for assessments. Combination treatments of genistein and IR resulted in no significant genistein effects on ddb2 and bax downstream transcripts to p53, or proliferating cell-nuclear antigen, pcna, necessary for DNA synthesis and cell-cycle progression. Use of these radiation-responsive targets would be recommended for dose-assessment applications. We also observed decreased expression of pro-survival transcript, bcl-2. Genistein and IR-increased expression of cdkn1a and gadd45a, showing that genistein also stimulates p53 transcriptional activity. These results confirm published molecular signatures for genistein in numerous in vitro models. Evaluation of gene biomarkers may be further exploited for devising novel radiation countermeasure and/or therapeutic strategies.

Analysis of the Kinetics and Regulation of Cytokine Gene Expression During the Primary In Vivo Immune Response to Killed Brucella Abortus

Science.gov (United States)

1992-08-10

Purified protein derivative of Mycobacterium tuberculosis and excretory-secretory antigen(s) of Toxocara canis expand in vitro human T cells with...day after immunization viii 47 49 LIST OF TABLES I. PCR primers and Southern blot probes of Th 11Th2 cytokines II. Cytokine mRNA levels in Thyl...sensitive quantitative reverse transcriptase-polymerase chain reaction (RT- PCR ) assay to measure changes in Thl and Th2 cytokine gene expression during

[Cloning and expressing of cyclophilin B gene from Schistosoma japonnicum and the analysis of immunoprotective effect].

Science.gov (United States)

Peng, Jinbiao; Han, Hongxiao; Hong, Yang; Wang, Yan; Guo, Fanji; Shi, Yaojun; Fu, Zhiqiang; Liu, Jinming; Cheng, Guofeng; Lin, Jiaojiao

2010-03-01

The present study was intend to clone and express the cDNA encoding Cyclophilin B (CyPB) of Schistosoma japonicum, its preliminary biological function and further immunoprotective effect against schistosome infection in mice. RT-PCR technique was applied to amplify a full-length cDNA encoding protein Cyclophilin B (Sj CyPB) from schistosomula cDNA. The expression profiles of Sj CyPB were determined by Real-time PCR using the template cDNAs isolated from 7, 13, 18, 23, 32 and 42 days parasites. The cDNA containing the Open Reading Frame of CyPB was then subcloned into a pGEX-6P-1 vector and transformed into competent Escherichia coli BL21 for expressing. The recombinant protein was renaturated, purified and its antigenicity were detected by Western blotting, and the immunoprotective effect induced by recombinant Sj CyPB was evaluated in Balb/C mice. The cDNA containing the ORF of Sj CyPB was cloned with the length of 672 base pairs, encoding 223 amino acids. Real-time PCR analysis revealed that the gene had the highest expression in 18-day schistosomula, suggesting that Sj CyPB was schistosomula differentially expressed gene. The recombinant protein showed a good antigenicity detected by Western blotting. Animal experiment indicated that the vaccination of recombinant CyPB protein in mice led to 31.5% worm and 41.01% liver egg burden reduction, respectively, compared with those of the control. A full-length cDNA differentially expressed in schistosomula was obtained. The recombinant Sj CyPB protein could induce partial protection against schistosome infection.

[Cloning expression and serological evaluation on Mycobacterium tuberculosis four new antigens].

Science.gov (United States)

Luo, Q; Li, S J; Xiao, T Y; Li, M C; Liu, H C; Lou, Y L; Wan, K L

2018-04-10

Objective: To evaluate the serological diagnostic value of Mycobacterium (M.) tuberculosis four new antigens Rv0432, Rv0674, Rv1566c and Rv1547. Methods: Rv0432, Rv0674, Rv1566c and Rv1547 were amplified from M. tuberculosis strain H37Rv genomic DNA by using PCR, among which Rv1547 was divided into two segments for amplification ( Rv1547-1 and Rv1547-2 ). The segments were cloned into expression vector PET-32a while the recombinant proteins were purified by affinity chromatography. Serums were incubated with BL21 (DE3) proteins. Antibodies IgG against M. tuberculosis were tested with 151 serum samples (41 healthy people and 110 TB patients) by using ELISA. The diagnostic efficiency of antigens was analyzed by means of receiver operating characteristic curve. Difference of the objective proteins in TB patients and healthy controls was compared by t -test. Results: Recombinant antigens Rv0432, Rv0674, Rv1566c, Rv1547-1 and Rv1547-2 were successfully expressed and purified. Results from ELISA showed that the sensitivity, specificity, positive predictive value, negative predictive value, Youden index and area under the curve of Rv0432, Rv0674, Rv1566c, Rv1547-1 and Rv1547-2, as 43.64%-92.73%, 80.49%-92.68%, 0.92-0.94, 0.38-0.80, 0.363-0.732 and 0.649-0.915. All the objective proteins showed significantly higher antibody levels in TB patients, when compared to the healthy controls ( P <0.000 1). Conclusion: The newly identified antigens Rv0432, Rv0674, Rv1566c, Rv1547-1 and Rv1547-2 all performed well when being used for TB serological diagnosis, thus were expected to be new candidate antigens used for TB diagnosis.

Differential Gene Expression and Aging

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Laurent Seroude

2002-01-01

Full Text Available It has been established that an intricate program of gene expression controls progression through the different stages in development. The equally complex biological phenomenon known as aging is genetically determined and environmentally modulated. This review focuses on the genetic component of aging, with a special emphasis on differential gene expression. At least two genetic pathways regulating organism longevity act by modifying gene expression. Many genes are also subjected to age-dependent transcriptional regulation. Some age-related gene expression changes are prevented by caloric restriction, the most robust intervention that slows down the aging process. Manipulating the expression of some age-regulated genes can extend an organism's life span. Remarkably, the activity of many transcription regulatory elements is linked to physiological age as opposed to chronological age, indicating that orderly and tightly controlled regulatory pathways are active during aging.

Novel Functions for Glycosyltransferases Jhp0562 and GalT in Lewis Antigen Synthesis and Variation in Helicobacter pylori

OpenAIRE

Pohl, Mary Ann; Kienesberger, Sabine; Blaser, Martin J.

2012-01-01

Lewis (Le) antigens are fucosylated oligosaccharides present in the Helicobacter pylori lipopolysaccharide. Expression of these antigens is believed to be important for H. pylori colonization, since Le antigens also are expressed on the gastric epithelia in humans. A galactosyltransferase encoded by β-(1,3)galT is essential for production of type 1 (Lea and Leb) antigens. The upstream gene jhp0562, which is present in many but not all H. pylori strains, is homologous to β-(1,3)galT but is of ...

Human Tumor Antigens Yesterday, Today, and Tomorrow.

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Finn, Olivera J

2017-05-01

The question of whether human tumors express antigens that can be recognized by the immune system has been answered with a resounding YES. Most were identified through spontaneous antitumor humoral and cellular immune responses found in cancer patients and include peptides, glycopeptides, phosphopeptides, viral peptides, and peptides resulting from common mutations in oncogenes and tumor-suppressor genes, or common gene fusion events. Many have been extensively tested as candidates for anticancer vaccines. More recently, attention has been focused on the potentially large number of unique tumor antigens, mutated neoantigens, that are the predicted products of the numerous mutations revealed by exome sequencing of primary tumors. Only a few have been confirmed as targets of spontaneous immunity and immunosurveillance, and even fewer have been tested in preclinical and clinical settings. The field has been divided for a long time on the relative importance of shared versus mutated antigens in tumor surveillance and as candidates for vaccines. This question will eventually need to be answered in a head to head comparison in well-designed clinical trials. One advantage that shared antigens have over mutated antigens is their potential to be used in vaccines for primary cancer prevention. Cancer Immunol Res; 5(5); 347-54. ©2017 AACR . ©2017 American Association for Cancer Research.

Lack of ADAM2, CALR3 and SAGE1 Cancer/Testis Antigen Expression in Lung and Breast Cancer

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Maheswaran, Emeaga; Pedersen, Christina B; Ditzel, Henrik J

2015-01-01

and antigenic properties, but the expression patterns of most of the more than 200 identified cancer/testis antigens in various cancers remain largely uncharacterized. In this study, we investigated the expression of the cancer/testis antigens ADAM2, CALR3 and SAGE1 in lung and breast cancer, the two most...... frequent human cancers, with the purpose of providing novel therapeutic targets for these diseases. We used a set of previously uncharacterized antibodies against the cancer/testis antigens ADAM2, CALR3 and SAGE1 to investigate their expression in a large panel of normal tissues as well as breast and lung...... cancers. Staining for the well-characterized MAGE-A proteins was included for comparison. Immunohistochemical staining confirmed previous mRNA analysis demonstrating that ADAM2, CALR3 and SAGE1 proteins are confined to testis in normal individuals. Negative tissues included plancenta, which express many...

Polycistronic gene expression in Aspergillus niger.

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Schuetze, Tabea; Meyer, Vera

2017-09-25

Genome mining approaches predict dozens of biosynthetic gene clusters in each of the filamentous fungal genomes sequenced so far. However, the majority of these gene clusters still remain cryptic because they are not expressed in their natural host. Simultaneous expression of all genes belonging to a biosynthetic pathway in a heterologous host is one approach to activate biosynthetic gene clusters and to screen the metabolites produced for bioactivities. Polycistronic expression of all pathway genes under control of a single and tunable promoter would be the method of choice, as this does not only simplify cloning procedures, but also offers control on timing and strength of expression. However, polycistronic gene expression is a feature not commonly found in eukaryotic host systems, such as Aspergillus niger. In this study, we tested the suitability of the viral P2A peptide for co-expression of three genes in A. niger. Two genes descend from Fusarium oxysporum and are essential to produce the secondary metabolite enniatin (esyn1, ekivR). The third gene (luc) encodes the reporter luciferase which was included to study position effects. Expression of the polycistronic gene cassette was put under control of the Tet-On system to ensure tunable gene expression in A. niger. In total, three polycistronic expression cassettes which differed in the position of luc were constructed and targeted to the pyrG locus in A. niger. This allowed direct comparison of the luciferase activity based on the position of the luciferase gene. Doxycycline-mediated induction of the Tet-On expression cassettes resulted in the production of one long polycistronic mRNA as proven by Northern analyses, and ensured comparable production of enniatin in all three strains. Notably, gene position within the polycistronic expression cassette matters, as, luciferase activity was lowest at position one and had a comparable activity at positions two and three. The P2A peptide can be used to express at

A re-assessment of gene-tag classification approaches for describing var gene expression patterns during human Plasmodium falciparum malaria parasite infections.

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Githinji, George; Bull, Peter C

2017-01-01

PfEMP1 are variant parasite antigens that are inserted on the surface of Plasmodium falciparum infected erythrocytes (IE). Through interactions with various host molecules, PfEMP1 mediate IE sequestration in tissues and play a key role in the pathology of severe malaria. PfEMP1 is encoded by a diverse multi-gene family called var . Previous studies have shown that that expression of specific subsets of var genes are associated with low levels of host immunity and severe malaria. However, in most clinical studies to date, full-length var gene sequences were unavailable and various approaches have been used to make comparisons between var gene expression profiles in different parasite isolates using limited information. Several studies have relied on the classification of a 300 - 500 base-pair "DBLα tag" region in the DBLα domain located at the 5' end of most var genes. We assessed the relationship between various DBLα tag classification methods, and sequence features that are only fully assessable through full-length var gene sequences. We compared these different sequence features in full-length var gene from six fully sequenced laboratory isolates. These comparisons show that despite a long history of recombination,   DBLα sequence tag classification can provide functional information on important features of full-length var genes. Notably, a specific subset of DBLα tags previously defined as "group A-like" is associated with CIDRα1 domains proposed to bind to endothelial protein C receptor. This analysis helps to bring together different sources of data that have been used to assess var gene expression in clinical parasite isolates.

Validation of cell-free culture using scanning electron microscopy (SEM) and gene expression studies.

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Yang, R; Elankumaran, Y; Hijjawi, N; Ryan, U

2015-06-01

A cell-free culture system for Cryptosporidium parvum was analysed using scanning electron microscopy (SEM) to characterise life cycle stages and compare gene expression in cell-free culture and cell culture using HCT-8 cells. Cryptosporidium parvum samples were harvested at 2 h, 8 h, 14 h, 26 h, 50 h, 74 h, 98 h, 122 h and 170 h, chemically fixed and specimens were observed using a Zeiss 1555 scanning electron microscope. The presence of sporozoites, trophozoites and type I merozoites were identified by SEM. Gene expression in cell culture and cell-free culture was studied using reverse transcriptase quantitative PCR (RT-qPCR) of the sporozoite surface antigen protein (cp15), the glycoprotein 900 (gp900), the Cryptosporidium oocyst wall protein (COWP) and 18S ribosomal RNA (rRNA) genes in both cell free and conventional cell culture. In cell culture, cp15 expression peaked at 74 h, gp900 expression peaked at 74 h and 98 h and COWP expression peaked at 50 h. In cell-free culture, CP15 expression peaked at 98 h, gp900 expression peaked at 74 h and COWP expression peaked at 122 h. The present study is the first to compare gene expression of C. parvum in cell culture and cell-free culture and to characterise life cycle stages of C. parvum in cell-free culture using SEM. Findings from this study showed that gene expression patterns in cell culture and cell-free culture were similar but in cell-free culture, gene expression was delayed for CP15 and COWP in cell free culture compared with the cell culture system and was lower. Although three life cycle stageswere conclusively identified, improvements in SEM methodology should lead to the detection of more life cycle stages. Copyright © 2015 Elsevier Inc. All rights reserved.

In vitro selection of Plasmodium falciparum 3D7 for expression of variant surface antigens associated with severe malaria in African children

DEFF Research Database (Denmark)

Staalsoe, Trine; Nielsen, Morten A; Vestergaard, Lasse S

2003-01-01

) in older semi-immune children. Establishment of the genetic mechanism underlying changes in VSA expression in response to in vitro selective pressure is now possible because of the availability of the entire genomic sequence of the P. falciparum clone 3D7. As a first step towards direct molecular...... identification of VSASM-encoding genes in 3D7, we report here a method of enforcing expression of VSASM-like antigens in this parasite clone by a novel selection method using plasma from semi-immune children with low VSAUM-specific, but high VSASM-specific, IgG reactivity. In addition to the resulting increase...... and epidemiologically diverse areas of endemic parasite transmission. The described selection method appears a useful tool in the identification of genes encoding VSA involved in severe and life-threatening P. falciparum malaria....

Gene expression profiling in gastric mucosa from Helicobacter pylori-infected and uninfected patients undergoing chronic superficial gastritis.

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Ze-Min Yang

Full Text Available Helicobacter pylori infection reprograms host gene expression and influences various cellular processes, which have been investigated by cDNA microarray using in vitro culture cells and in vivo gastric biopsies from patients of the Chronic Abdominal Complaint. To further explore the effects of H. pylori infection on host gene expression, we have collected the gastric antral mucosa samples from 6 untreated patients with gastroscopic and pathologic confirmation of chronic superficial gastritis. Among them three patients were infected by H. pylori and the other three patients were not. These samples were analyzed by a microarray chip which contains 14,112 cloned cDNAs, and microarray data were analyzed via BRB ArrayTools software and Ingenuity Pathways Analysis (IPA website. The results showed 34 genes of 38 differentially expressed genes regulated by H. pylori infection had been annotated. The annotated genes were involved in protein metabolism, inflammatory and immunological reaction, signal transduction, gene transcription, trace element metabolism, and so on. The 82% of these genes (28/34 were categorized in three molecular interaction networks involved in gene expression, cancer progress, antigen presentation and inflammatory response. The expression data of the array hybridization was confirmed by quantitative real-time PCR assays. Taken together, these data indicated that H. pylori infection could alter cellular gene expression processes, escape host defense mechanism, increase inflammatory and immune responses, activate NF-κB and Wnt/β-catenin signaling pathway, disturb metal ion homeostasis, and induce carcinogenesis. All of these might help to explain H. pylori pathogenic mechanism and the gastroduodenal pathogenesis induced by H. pylori infection.

In vivo and in vitro expression of myeloid antigens on B-lineage acute lymphoblastic leukemia cells.

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Hara, J; Kawa-Ha, K; Yumura-Yagi, K; Kurahashi, H; Tawa, A; Ishihara, S; Inoue, M; Murayama, N; Okada, S

1991-01-01

The expression of myeloid antigens has been extensively examined using two-color analysis in 43 children with B-lineage acute lymphoblastic leukemia (ALL). On pre-culture cells, CD33 expression was frequently observed in CD19+, CD10- B-precursor ALL, and CD14 was expressed only on the cells from B-precursor ALL expressing CD19, CD10 and CD20, and B-ALL. After 2 or 3 days of culture without TPA, CD13 emerged on the cells from 21 of 29 patients irrespective of the presence or the absence of fetal calf serum in the culture. Of four patients with CD10+ B-precursor ALL, which showed no expression of CD13 after culture, two had T-cell associated antigens. Whereas the addition of TPA to the culture enhanced the expression of CD13 on the cells from acute non-lymphocytic leukemia (ANLL), TPA reduced the expression of this antigen on B-precursor cells. These findings suggest that the regulatory mechanism of CD13 expression may be different between B-precursor ALL and ANLL. Co-culture with cycloheximide mostly abrogated the induction of CD13, suggesting that CD13 expression was mainly dependent on de novo protein synthesis.

Presymptomatic Diagnosis of Celiac Disease in Predisposed Children: The Role of Gene Expression Profile.

Science.gov (United States)

Galatola, Martina; Cielo, Donatella; Panico, Camilla; Stellato, Pio; Malamisura, Basilio; Carbone, Lorenzo; Gianfrani, Carmen; Troncone, Riccardo; Greco, Luigi; Auricchio, Renata

2017-09-01

The prevalence of celiac disease (CD) has increased significantly in recent years, and risk prediction and early diagnosis have become imperative especially in at-risk families. In a previous study, we identified individuals with CD based on the expression profile of a set of candidate genes in peripheral blood monocytes. Here we evaluated the expression of a panel of CD candidate genes in peripheral blood mononuclear cells from at-risk infants long time before any symptom or production of antibodies. We analyzed the gene expression of a set of 9 candidate genes, associated with CD, in 22 human leukocyte antigen predisposed children from at-risk families for CD, studied from birth to 6 years of age. Nine of them developed CD (patients) and 13 did not (controls). We analyzed gene expression at 3 different time points (age matched in the 2 groups): 4-19 months before diagnosis, at the time of CD diagnosis, and after at least 1 year of a gluten-free diet. At similar age points, controls were also evaluated. Three genes (KIAA, TAGAP [T-cell Activation GTPase Activating Protein], and SH2B3 [SH2B Adaptor Protein 3]) were overexpressed in patients, compared with controls, at least 9 months before CD diagnosis. At a stepwise discriminant analysis, 4 genes (RGS1 [Regulator of G-protein signaling 1], TAGAP, TNFSF14 [Tumor Necrosis Factor (Ligand) Superfamily member 14], and SH2B3) differentiate patients from controls before serum antibodies production and clinical symptoms. Multivariate equation correctly classified CD from non-CD children in 95.5% of patients. The expression of a small set of candidate genes in peripheral blood mononuclear cells can predict CD at least 9 months before the appearance of any clinical and serological signs of the disease.

Monoclonal antibodies to murine thrombospondin-1 and thrombospondin-2 reveal differential expression patterns in cancer and low antigen expression in normal tissues

International Nuclear Information System (INIS)

Bujak, Emil; Pretto, Francesca; Ritz, Danilo; Gualandi, Laura; Wulhfard, Sarah; Neri, Dario

2014-01-01

There is a considerable interest for the discovery and characterization of tumor-associated antigens, which may facilitate antibody-based pharmacodelivery strategies. Thrombospondin-1 and thrombospondin-2 are homologous secreted proteins, which have previously been reported to be overexpressed during remodeling typical for wound healing and tumor progression and to possibly play a functional role in cell proliferation, migration and apoptosis. To our knowledge, a complete immunohistochemical characterization of thrombospondins levels in normal rodent tissues has not been reported so far. Using antibody phage technology, we have generated and characterized monoclonal antibodies specific to murine thrombospondin-1 and thrombospondin-2, two antigens which share 62% aminoacid identity. An immunofluorescence analysis revealed that both antigens are virtually undetectable in normal mouse tissues, except for a weak staining of heart tissue by antibodies specific to thrombospondin-1. The analysis also showed that thrombospondin-1 was strongly expressed in 5/7 human tumors xenografted in nude mice, while it was only barely detectable in 3/8 murine tumors grafted in immunocompetent mice. By contrast, a high-affinity antibody to thrombospondin-2 revealed a much lower level of expression of this antigen in cancer specimens. Our analysis resolves ambiguities related to conflicting reports on thrombosponding expression in health and disease. Based on our findings, thrombospondin-1 (and not thrombospondin-2) may be considered as a target for antibody-based pharmacodelivery strategies, in consideration of its low expression in normal tissues and its upregulation in cancer. - Highlights: • High affinity monoclonal antibodies to murine and human TSP1 and 2 were raised. • Both antigens are virtually undetectable in normal mouse tissues. • Strong positivity of human tumor xenografts for TSP1 was detected. • Study revealed much lower level of TSP2 expression in cancer specimens

Monoclonal antibodies to murine thrombospondin-1 and thrombospondin-2 reveal differential expression patterns in cancer and low antigen expression in normal tissues

Energy Technology Data Exchange (ETDEWEB)

Bujak, Emil [Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology (ETH Zürich), Vladimir-Prelog-Weg 2, CH-8093 Zurich (Switzerland); Pretto, Francesca; Ritz, Danilo; Gualandi, Laura; Wulhfard, Sarah [Philochem AG, Libernstrasse 3, CH-8112 Otelfingen (Switzerland); Neri, Dario, E-mail: neri@pharma.ethz.ch [Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology (ETH Zürich), Vladimir-Prelog-Weg 2, CH-8093 Zurich (Switzerland)

2014-09-10

There is a considerable interest for the discovery and characterization of tumor-associated antigens, which may facilitate antibody-based pharmacodelivery strategies. Thrombospondin-1 and thrombospondin-2 are homologous secreted proteins, which have previously been reported to be overexpressed during remodeling typical for wound healing and tumor progression and to possibly play a functional role in cell proliferation, migration and apoptosis. To our knowledge, a complete immunohistochemical characterization of thrombospondins levels in normal rodent tissues has not been reported so far. Using antibody phage technology, we have generated and characterized monoclonal antibodies specific to murine thrombospondin-1 and thrombospondin-2, two antigens which share 62% aminoacid identity. An immunofluorescence analysis revealed that both antigens are virtually undetectable in normal mouse tissues, except for a weak staining of heart tissue by antibodies specific to thrombospondin-1. The analysis also showed that thrombospondin-1 was strongly expressed in 5/7 human tumors xenografted in nude mice, while it was only barely detectable in 3/8 murine tumors grafted in immunocompetent mice. By contrast, a high-affinity antibody to thrombospondin-2 revealed a much lower level of expression of this antigen in cancer specimens. Our analysis resolves ambiguities related to conflicting reports on thrombosponding expression in health and disease. Based on our findings, thrombospondin-1 (and not thrombospondin-2) may be considered as a target for antibody-based pharmacodelivery strategies, in consideration of its low expression in normal tissues and its upregulation in cancer. - Highlights: • High affinity monoclonal antibodies to murine and human TSP1 and 2 were raised. • Both antigens are virtually undetectable in normal mouse tissues. • Strong positivity of human tumor xenografts for TSP1 was detected. • Study revealed much lower level of TSP2 expression in cancer specimens

Genomic polymorphism, recombination, and linkage disequilibrium in human major histocompatibility complex-encoded antigen-processing genes.

Science.gov (United States)

van Endert, P M; Lopez, M T; Patel, S D; Monaco, J J; McDevitt, H O

1992-01-01

Recently, two subunits of a large cytosolic protease and two putative peptide transporter proteins were found to be encoded by genes within the class II region of the major histocompatibility complex (MHC). These genes have been suggested to be involved in the processing of antigenic proteins for presentation by MHC class I molecules. Because of the high degree of polymorphism in MHC genes, and previous evidence for both functional and polypeptide sequence polymorphism in the proteins encoded by the antigen-processing genes, we tested DNA from 27 consanguineous human cell lines for genomic polymorphism by restriction fragment length polymorphism (RFLP) analysis. These studies demonstrate a strong linkage disequilibrium between TAP1 and LMP2 RFLPs. Moreover, RFLPs, as well as a polymorphic stop codon in the telomeric TAP2 gene, appear to be in linkage disequilibrium with HLA-DR alleles and RFLPs in the HLA-DO gene. A high rate of recombination, however, seems to occur in the center of the complex, between the TAP1 and TAP2 genes. Images PMID:1360671

Evaluation of variants of melanoma-associated antigen genes and mRNA transcripts in melanomas of dogs.

Science.gov (United States)

Stell, Anneliese J; Dobson, Jane M; Scase, Timothy J; Catchpole, Brian

2009-12-01

OBJECTIVE-To characterize variability in melanoma-associated antigen (MAA) genes and gene expression in melanomas of dogs. ANIMALS-18 dogs with malignant melanomas and 8 healthy control dogs. PROCEDURES-cDNA was prepared from malignant melanoma biopsy specimens and from pigmented oral mucocutaneous tissues of healthy control dogs. Genomic DNA was extracted from poorly pigmented melanomas. A PCR assay was performed by use of Melan-A, SILV, or tyrosinase-specific primers. RESULTS-Splice variants of Melan-A and SILV were identified in malignant melanomas and also in healthy pigmented tissues, whereas a tyrosinase splice variant was detected in melanoma tissues only. A short interspersed nuclear element (SINE) insertion mutation was identified in the SILV gene in 1 of 10 poorly pigmented melanomas. Six novel exonic single nucleotide polymorphisms (SNPs; 3 synonymous and 3 nonsynonymous) were detected in the tyrosinase gene, and 1 nonsynonymous exonic SNP was detected in the SILV gene. CONCLUSIONS AND CLINICAL RELEVANCE-Variants of MAA mRNA were detected in malignant melanoma tissues of dogs. The importance of MAA alternative transcripts expressed in melanomas and normal pigmented tissues was unclear, but they may have represented a means of regulating melanin synthesis. The tyrosinase splice variant was detected only in melanomas and could potentially be a tumor-specific target for immunotherapy. A SILV SINE insertion mutation was identified in a melanoma from a Great Dane, a breed known to carry this mutation (associated with merle coat color). The nonsynonymous SNPs detected in tyrosinase and SILV transcripts did not appear to affect tumor pigmentation.

DNA mismatch repair related gene expression as potential biomarkers to assess cadmium exposure in Arabidopsis seedlings

International Nuclear Information System (INIS)

Liu Wan; Zhou Qixing; Li Peijun; Gao Hairong; Han, Y.P.; Li, X.J.; Yang, Y.S.; Li Yanzhi

2009-01-01

In the current study, Arabidopsis seedlings were hydroponically grown on MS media containing cadmium (Cd) of 0-2.0 mg L -1 for 60 h of treatment. Gene expression profiles were used to relate exposure to Cd with some altered biological responses and/or specific growth effects. RT-PCR analysis was used to quantitate mRNA expression for seven genes known to be involved in DNA mismatch repair (MMR) system and cell division. Results indicated that Cd concentrations of 0.25-2.0 mg L -1 cause increased total soluble protein levels in shoots of Arabidopsis seedlings in an inverted U-shaped dose-response manner. Exposure to 0.25 and 0.5 mg L -1 of Cd dramatically induced expression of four genes (i.e. proliferating cell nuclear antigen 2 (atPCNA 2), MutL1 homolog (atMLH1), MutS 2 homolog (atMSH2) and atMSH3) and five genes (i.e. atPCNA1,2, atMLH1 and atMSH2,7), respectively, in shoots of Arabidopsis seedlings; Exposure to 1.0 mg L -1 of Cd significantly elevated expression of only two genes (atMSH6,7), but caused prominent inhibition in expression of three genes (atPCNA2, atMLH1 and atMSH3) in shoots of Arabidopsis seedlings. The expression alterations of the above genes were independent of any biological effects such as survival, fresh weight and chlorophyll level of shoots. However, shoots of Arabidopsis seedlings exposed to 2.0 mg L -1 of Cd exhibited statistically prominent repression in expression of these seven genes, and showed incipient reduction of fresh weight and chlorophyll level. This research provides data concerning sensitivity of expression profiles of atMLH1, atMSH2,3,6,7 and atPCNA1,2 genes in Arabidopsis seedlings to Cd exposure, as well as the potential use of these gene expression patterns as representative molecular biomarkers indicative of Cd exposure and related biological effects.

Immunogenicity in pig-tailed macaques of poliovirus replicons expressing HIV-1 and SIV antigens and protection against SHIV-89.6P disease

International Nuclear Information System (INIS)

Fultz, Patricia N.; Stallworth, Jackie; Porter, Donna; Novak, Miroslav; Anderson, Marie J.; Morrow, Casey D.

2003-01-01

In the search for an effective vaccine against the human immunodeficiency virus (HIV), novel ways to deliver viral antigens are being evaluated. One such approach is the use of nonreplicating viral vectors encoding HIV and/or SIV genes that are expressed after infection of host cells. Nonreplicating poliovirus vectors, termed replicons, that expressed HIV-1/HXB2 and SIVmac239 gag and various HIV-1 env genes from different clades were tested for immunogenicity and protective efficacy against intravenous challenge of pig-tailed macaques with SHIV-89.6P. To maximize both cellular and humoral immune responses, a prime-boost regimen was used. Initially, macaques were immunized four times over 35 weeks by either the intranasal and intrarectal or the intramuscular (im) route with mixtures of poliovirus replicons expressing HIV-1 gag and multiple env genes. Immunization with replicons alone induced both serum antibodies and lymphocyte proliferative responses. After boosting with purified Env protein, neutralizing antibodies to SHIV-89.6P were induced in four of five immunized animals. In a second experiment, four macaques were immunized im three times over 27 weeks with replicons expressing the SIVmac239 gag and HIV-1/HXB2 env genes. All immunized animals were then boosted twice with purified HIV-1-89.6 rgp140-Env and SIVmac239 p55-Gag proteins. Four control animals received only the two protein inoculations. Immunized and control animals were then challenged intravenously with the pathogenic SHIV-89.6P. After challenge the animals were monitored for virus isolation from peripheral blood mononuclear cells and plasma viremia and for changes in virus-specific antibody titers. Naieve pig-tailed macaques experienced rapid loss of CD4 + T cells and died between 38 and 62 weeks after infection. In contrast, macaques immunized with replicons and proteins rapidly cleared plasma virus and did not experience sustained loss of CD4 + lymphocytes. Furthermore, two of the four macaques

Analysis of mechanism for human γδ T cell recognition of nonpeptide antigens

International Nuclear Information System (INIS)

Yamashita, Seiji; Tanaka, Yoshimasa; Tsutsumi, Shuichi; Aburatani, Hiroyuki; Minato, Nagahiro; Ihara, Sigeo

2005-01-01

Whereas human γδ T cells respond to nonpeptide antigens like pyrophosphomonoesters and alkyl amines in the primary reactions, only pyrophosphomonoesters provoke proliferative responses in the secondary responses. To elucidate the differences in stimulatory activity between the two groups of nonpeptide antigens, we systematically analyzed time courses of gene expressions by microarray analyses. While 253 genes were induced by stimulation with 2-methyl-3-butenyl-1-pyrophosphate (2M3B1PP), only 35 genes were detected after stimulation with isobutyl amine. Then, γδ T cells expressed various cytokines like XCL1-2, CCL3-4, TNF-α, and IFN-γ in response to 2M3B1PP in a time-dependent manner, while transient expressions were observed in IBA during the time period. The differences in such responsiveness are likely to originate from the activation state of NFAT, which is involved in the expression of transcription factors, EGR1-3 and NR4A1-2, and might play a crucial role in effector functions of γδ T cells

Gene expression inference with deep learning.

Science.gov (United States)

Chen, Yifei; Li, Yi; Narayan, Rajiv; Subramanian, Aravind; Xie, Xiaohui

2016-06-15

Large-scale gene expression profiling has been widely used to characterize cellular states in response to various disease conditions, genetic perturbations, etc. Although the cost of whole-genome expression profiles has been dropping steadily, generating a compendium of expression profiling over thousands of samples is still very expensive. Recognizing that gene expressions are often highly correlated, researchers from the NIH LINCS program have developed a cost-effective strategy of profiling only ∼1000 carefully selected landmark genes and relying on computational methods to infer the expression of remaining target genes. However, the computational approach adopted by the LINCS program is currently based on linear regression (LR), limiting its accuracy since it does not capture complex nonlinear relationship between expressions of genes. We present a deep learning method (abbreviated as D-GEX) to infer the expression of target genes from the expression of landmark genes. We used the microarray-based Gene Expression Omnibus dataset, consisting of 111K expression profiles, to train our model and compare its performance to those from other methods. In terms of mean absolute error averaged across all genes, deep learning significantly outperforms LR with 15.33% relative improvement. A gene-wise comparative analysis shows that deep learning achieves lower error than LR in 99.97% of the target genes. We also tested the performance of our learned model on an independent RNA-Seq-based GTEx dataset, which consists of 2921 expression profiles. Deep learning still outperforms LR with 6.57% relative improvement, and achieves lower error in 81.31% of the target genes. D-GEX is available at https://github.com/uci-cbcl/D-GEX CONTACT: xhx@ics.uci.edu Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Isolation of antigenic substances from HIV-1 envelope gp160 gene transfectants by mild acid elution and X-irradiation treatment. For the development of CTL-based immunotherapy

International Nuclear Information System (INIS)

Fujimoto, Chiaki; Nakagawa, Yohko; Shimizu, Masumi; Ohara, Kunitoshi; Takahashi, Hidemi

2003-01-01

Cytotoxic T lymphocytes (CTLs) play a central role in a broad spectrum of tumor immunity. Such CTLs generally recognize processed antigenic fragments in association with class I major histocompatibility complex (MHC) molecules. Thus, it is important to identify naturally processed antigens associated with class I MHC molecules to generate and activate antigen-specific CTLs. Those processed antigens fitted in the groove of class I MHC molecules are fixed by the β2-microglobulin. Mild acid elution is one method used to isolate antigenic fragments from class I MHC molecules on tumor cells by unfastening a clasp of β2-microglobulin, a critical component for stabilizing class I MHC molecules on the cell surface. Indeed, after the mild acid treatment, the expression of class I MHC molecules was temporarily down-modulated and a strong antigenic fraction for CTL recognition was obtained. To our surprise, such down-modulation of class I MHC molecule expression was also observed when the tumor cells were irradiated. Therefore, using human immunodeficiency virus type I (HIV-1) gp160 env gene transfectants, we examined the effect of X-irradiation on releasing the loaded antigenic fragments. Functional extracts were obtained from X-irradiated cell supernatants that sensitized syngeneic fibroblasts for specific CTL recognition, suggesting that X-irradiation extracts would also contain known antigenic epitopes. These results indicate that, in addition to the conventional mild acid elution treatment, X-irradiation method shown in this paper may provide a new approach for CTL-based vaccine development via isolating antigenic molecules from various tumors or virally infected cells. (author)

Candidate genes expressed in human islets and their role in the pathogenesis of type 1 diabetes

DEFF Research Database (Denmark)

Storling, Joachim; Brorsson, Caroline Anna

2013-01-01

In type 1 diabetes (T1D), the insulin-producing β cells are destroyed by an immune-mediated process leading to complete insulin deficiency. There is a strong genetic component in T1D. Genes located in the human leukocyte antigen (HLA) region are the most important genetic determinants of disease......, but more than 40 additional loci are known to significantly affect T1D risk. Since most of the currently known genetic candidates have annotated immune cell functions, it is generally considered that most of the genetic susceptibility in T1D is caused by variation in genes affecting immune cell function....... Recent studies, however, indicate that most T1D candidate genes are expressed in human islets suggesting that the functions of the genes are not restricted to immune cells, but also play roles in the islets and possibly the β cells. Several candidates change expression levels within the islets following...

The androgen receptor controls expression of the cancer-associated sTn antigen and cell adhesion through induction of ST6GalNAc1 in prostate cancer

Science.gov (United States)

Munkley, Jennifer; Oltean, Sebastian; Vodák, Daniel; Wilson, Brian T.; Livermore, Karen E.; Zhou, Yan; Star, Eleanor; Floros, Vasileios I.; Johannessen, Bjarne; Knight, Bridget; McCullagh, Paul; McGrath, John; Crundwell, Malcolm; Skotheim, Rolf I.; Robson, Craig N.; Leung, Hing Y.; Harries, Lorna W.; Rajan, Prabhakar; Mills, Ian G.; Elliott, David J.

2015-01-01

Patterns of glycosylation are important in cancer, but the molecular mechanisms that drive changes are often poorly understood. The androgen receptor drives prostate cancer (PCa) development and progression to lethal metastatic castration-resistant disease. Here we used RNA-Seq coupled with bioinformatic analyses of androgen-receptor (AR) binding sites and clinical PCa expression array data to identify ST6GalNAc1 as a direct and rapidly activated target gene of the AR in PCa cells. ST6GalNAc1 encodes a sialytransferase that catalyses formation of the cancer-associated sialyl-Tn antigen (sTn), which we find is also induced by androgen exposure. Androgens induce expression of a novel splice variant of the ST6GalNAc1 protein in PCa cells. This splice variant encodes a shorter protein isoform that is still fully functional as a sialyltransferase and able to induce expression of the sTn-antigen. Surprisingly, given its high expression in tumours, stable expression of ST6GalNAc1 in PCa cells reduced formation of stable tumours in mice, reduced cell adhesion and induced a switch towards a more mesenchymal-like cell phenotype in vitro. ST6GalNAc1 has a dynamic expression pattern in clinical datasets, being significantly up-regulated in primary prostate carcinoma but relatively down-regulated in established metastatic tissue. ST6GalNAc1 is frequently upregulated concurrently with another important glycosylation enzyme GCNT1 previously associated with prostate cancer progression and implicated in Sialyl Lewis X antigen synthesis. Together our data establishes an androgen-dependent mechanism for sTn antigen expression in PCa, and are consistent with a general role for the androgen receptor in driving important coordinate changes to the glycoproteome during PCa progression. PMID:26452038

The effect of mutation on Rhodococcus equi virulence plasmid gene expression and mouse virulence.

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Ren, Jun; Prescott, John F

2004-11-15

An 81 kb virulence plasmid containing a pathogenicity island (PI) plays a crucial role in the pathogenesis of Rhodococcus equi pneumonia in foals but its specific function in virulence and regulation of plasmid-encoded virulence genes is unclear. Using a LacZ selection marker developed for R. equi in this study, in combination with an apramycin resistance gene, an efficient two-stage homologous recombination targeted gene mutation procedure was used to mutate three virulence plasmid genes, a LysR regulatory gene homologue (ORF4), a ResD-like two-component response regulator homologue (ORF8), and a gene (ORF10) of unknown function that is highly expressed by R. equi inside macrophages, as well as the chromosomal gene operon, phoPR. Virulence testing by liver clearance after intravenous injection in mice showed that the ORF4 and ORF8 mutants were fully attenuated, that the phoPR mutant was hypervirulent, and that virulence of the ORF10 mutant remained unchanged. A virulence plasmid DNA microarray was used to compare the plasmid gene expression profile of each of the four gene-targeted mutants against the parental R. equi strain. Changes were limited to PI genes and gene induction was observed for all mutants, suggesting that expression of virulence plasmid genes is dominated by a negative regulatory network. The finding of attenuation of ORF4 and ORF8 mutants despite enhanced transcription of vapA suggests that factors other than VapA are important for full expression of virulence. ORF1, a putative Lsr antigen gene, was strongly and similarly induced in all mutants, implying a common regulatory pathway affecting this gene for all four mutated genes. ORF8 is apparently the centre of this common pathway. Two distinct highly correlated gene induction patterns were observed, that of the ORF4 and ORF8 mutants, and that of the ORF10 and phoPR mutants. The gene induction pattern distinguishing these two groups paralleled their virulence in mice.

Production of dengue virus envelope protein domain III-based antigens in tobacco chloroplasts using inducible and constitutive expression systems.

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Gottschamel, Johanna; Lössl, Andreas; Ruf, Stephanie; Wang, Yanliang; Skaugen, Morten; Bock, Ralph; Clarke, Jihong Liu

2016-07-01

Dengue fever is a disease in many parts of the tropics and subtropics and about half the world's population is at risk of infection according to the World Health Organization. Dengue is caused by any of the four related dengue virus serotypes DEN-1, -2, -3 and -4, which are transmitted to people by Aedes aegypti mosquitoes. Currently there is only one vaccine (Dengvaxia(®)) available (limited to a few countries) on the market since 2015 after half a century's intensive efforts. Affordable and accessible vaccines against dengue are hence still urgently needed. The dengue envelop protein domain III (EDIII), which is capable of eliciting serotype-specific neutralizing antibodies, has become the focus for subunit vaccine development. To contribute to the development of an accessible and affordable dengue vaccine, in the current study we have used plant-based vaccine production systems to generate a dengue subunit vaccine candidate in tobacco. Chloroplast genome engineering was applied to express serotype-specific recombinant EDIII proteins in tobacco chloroplasts using both constitutive and ethanol-inducible expression systems. Expression of a tetravalent antigen fusion construct combining EDIII polypeptides from all four serotypes was also attempted. Transplastomic EDIII-expressing tobacco lines were obtained and homoplasmy was verified by Southern blot analysis. Northern blot analyses showed expression of EDIII antigen-encoding genes. EDIII protein accumulation levels varied for the different recombinant EDIII proteins and the different expression systems, and reached between 0.8 and 1.6 % of total cellular protein. Our study demonstrates the suitability of the chloroplast compartment as a production site for an EDIII-based vaccine candidate against dengue fever and presents a Gateway(®) plastid transformation vector for inducible transgene expression.

New Data on Vaccine Antigen Deficient Bordetella pertussis Isolates

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Valérie Bouchez

2015-09-01

Full Text Available Evolution of Bordetella pertussis is driven by natural and vaccine pressures. Isolates circulating in regions with high vaccination coverage present multiple allelic and antigenic variations as compared to isolates collected before introduction of vaccination. Furthermore, during the last epidemics reported in regions using pertussis acellular vaccines, isolates deficient for vaccine antigens, such as pertactin (PRN, were reported to reach high proportions of circulating isolates. More sporadic filamentous hemagglutinin (FHA or pertussis toxin (PT deficient isolates were also collected. The whole genome of some recent French isolates, deficient or non-deficient in vaccine antigens, were analyzed. Transcription profiles of the expression of the main virulence factors were also compared. The invasive phenotype in an in vitro human tracheal epithelial (HTE cell model of infection was evaluated. Our genomic analysis focused on SNPs related to virulence genes known to be more likely to present allelic polymorphism. Transcriptomic data indicated that isolates circulating since the introduction of pertussis vaccines present lower transcription levels of the main virulence genes than the isolates of the pre-vaccine era. Furthermore, isolates not producing FHA present significantly higher expression levels of the entire set of genes tested. Finally, we observed that recent isolates are more invasive in HTE cells when compared to the reference strain, but no multiplication occurs within cells.

An inducible transgenic mouse model for immune mediated hepatitis showing clearance of antigen expressing hepatocytes by CD8+ T cells.

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Marcin Cebula

Full Text Available The liver has the ability to prime immune responses against neo antigens provided upon infections. However, T cell immunity in liver is uniquely modulated by the complex tolerogenic property of this organ that has to also cope with foreign agents such as endotoxins or food antigens. In this respect, the nature of intrahepatic T cell responses remains to be fully characterized. To gain deeper insight into the mechanisms that regulate the CD8+ T cell responses in the liver, we established a novel OVA_X_CreER(T2 mouse model. Upon tamoxifen administration OVA antigen expression is observed in a fraction of hepatocytes, resulting in a mosaic expression pattern. To elucidate the cross-talk of CD8+ T cells with antigen-expressing hepatocytes, we adoptively transferred K(b/OVA257-264-specific OT-I T cells to OVA_X_CreER(T2 mice or generated triple transgenic OVA_X CreER(T2_X_OT-I mice. OT-I T cells become activated in OVA_X_CreER(T2 mice and induce an acute and transient hepatitis accompanied by liver damage. In OVA_X_CreER(T2_X_OT-I mice, OVA induction triggers an OT-I T cell mediated, fulminant hepatitis resulting in 50% mortality. Surviving mice manifest a long lasting hepatitis, and recover after 9 weeks. In these experimental settings, recovery from hepatitis correlates with a complete loss of OVA expression indicating efficient clearance of the antigen-expressing hepatocytes. Moreover, a relapse of hepatitis can be induced upon re-induction of cured OVA_X_CreER(T2_X_OT-I mice indicating absence of tolerogenic mechanisms. This pathogen-free, conditional mouse model has the advantage of tamoxifen inducible tissue specific antigen expression that reflects the heterogeneity of viral antigen expression and enables the study of intrahepatic immune responses to both de novo and persistent antigen. It allows following the course of intrahepatic immune responses: initiation, the acute phase and antigen clearance.

Scaling of gene expression data allowing the comparison of different gene expression platforms

NARCIS (Netherlands)

van Ruissen, Fred; Schaaf, Gerben J.; Kool, Marcel; Baas, Frank; Ruijter, Jan M.

2008-01-01

Serial analysis of gene expression (SAGE) and microarrays have found a widespread application, but much ambiguity exists regarding the amalgamation of the data resulting from these technologies. Cross-platform utilization of gene expression data from the SAGE and microarray technology could reduce

cis sequence effects on gene expression

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Jacobs Kevin

2007-08-01

Full Text Available Abstract Background Sequence and transcriptional variability within and between individuals are typically studied independently. The joint analysis of sequence and gene expression variation (genetical genomics provides insight into the role of linked sequence variation in the regulation of gene expression. We investigated the role of sequence variation in cis on gene expression (cis sequence effects in a group of genes commonly studied in cancer research in lymphoblastoid cell lines. We estimated the proportion of genes exhibiting cis sequence effects and the proportion of gene expression variation explained by cis sequence effects using three different analytical approaches, and compared our results to the literature. Results We generated gene expression profiling data at N = 697 candidate genes from N = 30 lymphoblastoid cell lines for this study and used available candidate gene resequencing data at N = 552 candidate genes to identify N = 30 candidate genes with sufficient variance in both datasets for the investigation of cis sequence effects. We used two additive models and the haplotype phylogeny scanning approach of Templeton (Tree Scanning to evaluate association between individual SNPs, all SNPs at a gene, and diplotypes, with log-transformed gene expression. SNPs and diplotypes at eight candidate genes exhibited statistically significant (p cis sequence effects in our study, respectively. Conclusion Based on analysis of our results and the extant literature, one in four genes exhibits significant cis sequence effects, and for these genes, about 30% of gene expression variation is accounted for by cis sequence variation. Despite diverse experimental approaches, the presence or absence of significant cis sequence effects is largely supported by previously published studies.

Extracting gene expression patterns and identifying co-expressed genes from microarray data reveals biologically responsive processes

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Paules Richard S

2007-11-01

Full Text Available Abstract Background A common observation in the analysis of gene expression data is that many genes display similarity in their expression patterns and therefore appear to be co-regulated. However, the variation associated with microarray data and the complexity of the experimental designs make the acquisition of co-expressed genes a challenge. We developed a novel method for Extracting microarray gene expression Patterns and Identifying co-expressed Genes, designated as EPIG. The approach utilizes the underlying structure of gene expression data to extract patterns and identify co-expressed genes that are responsive to experimental conditions. Results Through evaluation of the correlations among profiles, the magnitude of variation in gene expression profiles, and profile signal-to-noise ratio's, EPIG extracts a set of patterns representing co-expressed genes. The method is shown to work well with a simulated data set and microarray data obtained from time-series studies of dauer recovery and L1 starvation in C. elegans and after ultraviolet (UV or ionizing radiation (IR-induced DNA damage in diploid human fibroblasts. With the simulated data set, EPIG extracted the appropriate number of patterns which were more stable and homogeneous than the set of patterns that were determined using the CLICK or CAST clustering algorithms. However, CLICK performed better than EPIG and CAST with respect to the average correlation between clusters/patterns of the simulated data. With real biological data, EPIG extracted more dauer-specific patterns than CLICK. Furthermore, analysis of the IR/UV data revealed 18 unique patterns and 2661 genes out of approximately 17,000 that were identified as significantly expressed and categorized to the patterns by EPIG. The time-dependent patterns displayed similar and dissimilar responses between IR and UV treatments. Gene Ontology analysis applied to each pattern-related subset of co-expressed genes revealed underlying

Structure and expression of the Xenopus retinoblastoma gene.

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Destrée, O H; Lam, K T; Peterson-Maduro, L J; Eizema, K; Diller, L; Gryka, M A; Frebourg, T; Shibuya, E; Friend, S H

1992-09-01

We have cloned a Xenopus homology (XRb1) of the human retinoblastoma susceptibility gene. DNA sequence analysis shows that the XRb1 gene product is highly conserved in many regions. The leucine repeat motif and many of the potential cdc2 phosphorylation sites, as well as potential sites for other kinases, are retained. The region of the protein homologous to the SV40 T antigen binding site and the basic region directly C-terminal to the E1A binding site are all conserved. XRb1 gene expression at the RNA level was studied by Northern blot analysis. Transcripts of 4.2 and 10-kb are present as maternal RNA stores in the oocyte. While the 4.2-kb product is stable until at least the mid-blastula stage, the 10-kb transcript is selectively degraded. Between stages 11 and 13 the 10-kb transcript reappears and also a minor product of approximately 11 kb becomes apparent. Both the 4.2- and the 10-kb transcripts remain present until later stages of development and are also present in all adult tissues examined, although at differing levels. Antibodies raised against human p105Rb which recognize the protein product of the XRb1 gene, pXRb1, detect the Xenopus 99-kDa protein prior to the mid-blastula stage, but at lower levels than at later stages in development.

Renal Gene Expression Database (RGED): a relational database of gene expression profiles in kidney disease.

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Zhang, Qingzhou; Yang, Bo; Chen, Xujiao; Xu, Jing; Mei, Changlin; Mao, Zhiguo

2014-01-01

We present a bioinformatics database named Renal Gene Expression Database (RGED), which contains comprehensive gene expression data sets from renal disease research. The web-based interface of RGED allows users to query the gene expression profiles in various kidney-related samples, including renal cell lines, human kidney tissues and murine model kidneys. Researchers can explore certain gene profiles, the relationships between genes of interests and identify biomarkers or even drug targets in kidney diseases. The aim of this work is to provide a user-friendly utility for the renal disease research community to query expression profiles of genes of their own interest without the requirement of advanced computational skills. Website is implemented in PHP, R, MySQL and Nginx and freely available from http://rged.wall-eva.net. http://rged.wall-eva.net. © The Author(s) 2014. Published by Oxford University Press.

Renal Gene Expression Database (RGED): a relational database of gene expression profiles in kidney disease

Science.gov (United States)

Zhang, Qingzhou; Yang, Bo; Chen, Xujiao; Xu, Jing; Mei, Changlin; Mao, Zhiguo

2014-01-01

We present a bioinformatics database named Renal Gene Expression Database (RGED), which contains comprehensive gene expression data sets from renal disease research. The web-based interface of RGED allows users to query the gene expression profiles in various kidney-related samples, including renal cell lines, human kidney tissues and murine model kidneys. Researchers can explore certain gene profiles, the relationships between genes of interests and identify biomarkers or even drug targets in kidney diseases. The aim of this work is to provide a user-friendly utility for the renal disease research community to query expression profiles of genes of their own interest without the requirement of advanced computational skills. Availability and implementation: Website is implemented in PHP, R, MySQL and Nginx and freely available from http://rged.wall-eva.net. Database URL: http://rged.wall-eva.net PMID:25252782

Modulation of gene expression made easy

DEFF Research Database (Denmark)

Solem, Christian; Jensen, Peter Ruhdal

2002-01-01

A new approach for modulating gene expression, based on randomization of promoter (spacer) sequences, was developed. The method was applied to chromosomal genes in Lactococcus lactis and shown to generate libraries of clones with broad ranges of expression levels of target genes. In one example...... that the method can be applied to modulating the expression of native genes on the chromosome. We constructed a series of strains in which the expression of the las operon, containing the genes pfk, pyk, and ldh, was modulated by integrating a truncated copy of the pfk gene. Importantly, the modulation affected...

Comparative analysis of human conjunctival and corneal epithelial gene expression with oligonucleotide microarrays.

Science.gov (United States)

Turner, Helen C; Budak, Murat T; Akinci, M A Murat; Wolosin, J Mario

2007-05-01

To determine global mRNA expression levels in corneal and conjunctival epithelia and identify transcripts that exhibit preferential tissue expression. cDNA samples derived from human conjunctival and corneal epithelia were hybridized in three independent experiments to a commercial oligonucleotide array representing more than 22,000 transcripts. The resultant signal intensities and microarray software transcript present/absent calls were used in conjunction with the local pooled error (LPE) statistical method to identify transcripts that are preferentially or exclusively expressed in one of the two tissues at significant levels (expression >1% of the beta-actin level). EASE (Expression Analysis Systematic Explorer software) was used to identify biological systems comparatively overrepresented in either epithelium. Immuno-, and cytohistochemistry was performed to validate or expand on selected results of interest. The analysis identified 332 preferential and 93 exclusive significant corneal epithelial transcripts. The corresponding numbers of conjunctival epithelium transcripts were 592 and 211, respectively. The overrepresented biological processes in the cornea were related to cell adhesion and oxiredox equilibria and cytoprotection activities. In the conjunctiva, the biological processes that were most prominent were related to innate immunity and melanogenesis. Immunohistochemistry for antigen-presenting cells and melanocytes was consistent with these gene signatures. The transcript comparison identified a substantial number of genes that have either not been identified previously or are not known to be highly expressed in these two epithelia, including testican-1, ECM1, formin, CRTAC1, and NQO1 in the cornea and, in the conjunctiva, sPLA(2)-IIA, lipocalin 2, IGFBP3, multiple MCH class II proteins, and the Na-Pi cotransporter type IIb. Comparative gene expression profiling leads to the identification of many biological processes and previously unknown genes that

Using gene expression noise to understand gene regulation

NARCIS (Netherlands)

Munsky, B.; Neuert, G.; van Oudenaarden, A.

2012-01-01

Phenotypic variation is ubiquitous in biology and is often traceable to underlying genetic and environmental variation. However, even genetically identical cells in identical environments display variable phenotypes. Stochastic gene expression, or gene expression "noise," has been suggested as a

Co-Introduced Functional CCR2 Potentiates In Vivo Anti-Lung Cancer Functionality Mediated by T Cells Double Gene-Modified to Express WT1-Specific T-Cell Receptor

Science.gov (United States)

Asai, Hiroaki; Fujiwara, Hiroshi; An, Jun; Ochi, Toshiki; Miyazaki, Yukihiro; Nagai, Kozo; Okamoto, Sachiko; Mineno, Junichi; Kuzushima, Kiyotaka; Shiku, Hiroshi; Inoue, Hirofumi; Yasukawa, Masaki

2013-01-01

Background and Purpose Although gene-modification of T cells to express tumor-related antigen-specific T-cell receptor (TCR) or chimeric antigen receptor (CAR) has clinically proved promise, there still remains room to improve the clinical efficacy of re-directed T-cell based antitumor adoptive therapy. In order to achieve more objective clinical responses using ex vivo-expanded tumor-responsive T cells, the infused T cells need to show adequate localized infiltration into the tumor. Methodology/Principal Findings Human lung cancer cells variously express a tumor antigen, Wilms' Tumor gene product 1 (WT1), and an inflammatory chemokine, CCL2. However, CCR2, the relevant receptor for CCL2, is rarely expressed on activated T-lymphocytes. A HLA-A2402+ human lung cancer cell line, LK79, which expresses high amounts of both CCL2 and WT1 mRNA, was employed as a target. Normal CD8+ T cells were retrovirally gene-modified to express both CCR2 and HLA-A*2402-restricted and WT1235–243 nonapeptide-specific TCR as an effector. Anti-tumor functionality mediated by these effector cells against LK79 cells was assessed both in vitro and in vivo. Finally the impact of CCL2 on WT1 epitope-responsive TCR signaling mediated by the effector cells was studied. Introduced CCR2 was functionally validated using gene-modified Jurkat cells and human CD3+ T cells both in vitro and in vivo. Double gene-modified CD3+ T cells successfully demonstrated both CCL2-tropic tumor trafficking and cytocidal reactivity against LK79 cells in vitro and in vivo. CCL2 augmented the WT1 epitope-responsive TCR signaling shown by relevant luciferase production in double gene-modified Jurkat/MA cells to express luciferase and WT1-specific TCR, and CCL2 also dose-dependently augmented WT1 epitope-responsive IFN-γ production and CD107a expression mediated by these double gene-modifiedCD3+ T cells. Conclusion/Significance Introduction of the CCL2/CCR2 axis successfully potentiated in vivo anti-lung cancer

Co-introduced functional CCR2 potentiates in vivo anti-lung cancer functionality mediated by T cells double gene-modified to express WT1-specific T-cell receptor.

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Hiroaki Asai

Full Text Available BACKGROUND AND PURPOSE: Although gene-modification of T cells to express tumor-related antigen-specific T-cell receptor (TCR or chimeric antigen receptor (CAR has clinically proved promise, there still remains room to improve the clinical efficacy of re-directed T-cell based antitumor adoptive therapy. In order to achieve more objective clinical responses using ex vivo-expanded tumor-responsive T cells, the infused T cells need to show adequate localized infiltration into the tumor. METHODOLOGY/PRINCIPAL FINDINGS: Human lung cancer cells variously express a tumor antigen, Wilms' Tumor gene product 1 (WT1, and an inflammatory chemokine, CCL2. However, CCR2, the relevant receptor for CCL2, is rarely expressed on activated T-lymphocytes. A HLA-A2402(+ human lung cancer cell line, LK79, which expresses high amounts of both CCL2 and WT1 mRNA, was employed as a target. Normal CD8(+ T cells were retrovirally gene-modified to express both CCR2 and HLA-A*2402-restricted and WT1(235-243 nonapeptide-specific TCR as an effector. Anti-tumor functionality mediated by these effector cells against LK79 cells was assessed both in vitro and in vivo. Finally the impact of CCL2 on WT1 epitope-responsive TCR signaling mediated by the effector cells was studied. Introduced CCR2 was functionally validated using gene-modified Jurkat cells and human CD3(+ T cells both in vitro and in vivo. Double gene-modified CD3(+ T cells successfully demonstrated both CCL2-tropic tumor trafficking and cytocidal reactivity against LK79 cells in vitro and in vivo. CCL2 augmented the WT1 epitope-responsive TCR signaling shown by relevant luciferase production in double gene-modified Jurkat/MA cells to express luciferase and WT1-specific TCR, and CCL2 also dose-dependently augmented WT1 epitope-responsive IFN-γ production and CD107a expression mediated by these double gene-modified CD3(+ T cells. CONCLUSION/SIGNIFICANCE: Introduction of the CCL2/CCR2 axis successfully potentiated in

The Mycobacterium leprae antigen 85 complex gene family: identification of the genes for the 85A, 85C, and related MPT51 proteins

NARCIS (Netherlands)

Rinke de Wit, T. F.; Bekelie, S.; Osland, A.; Wieles, B.; Janson, A. A.; Thole, J. E.

1993-01-01

The genes for two novel members (designated 85A and 85C) of the Mycobacterium leprae antigen 85 complex family of proteins and the gene for the closely related M. leprae MPT51 protein were isolated. The complete DNA sequence of the M. leprae 85C gene and partial sequences of the 85A and MPT51 genes

Early prostate cancer antigen expression in predicting presence of prostate cancer in men with histologically negative biopsies.

Science.gov (United States)

Hansel, D E; DeMarzo, A M; Platz, E A; Jadallah, S; Hicks, J; Epstein, J I; Partin, A W; Netto, G J

2007-05-01

Early prostate cancer antigen is a nuclear matrix protein that was recently shown to be expressed in prostate adenocarcinoma and adjacent benign tissue. Previous studies have demonstrated early prostate cancer antigen expression in benign prostate tissue up to 5 years before a diagnosis of prostate carcinoma, suggesting that early prostate cancer antigen could be used as a potential predictive marker. We evaluated early prostate cancer antigen expression by immunohistochemistry using a polyclonal antibody (Onconome Inc., Seattle, Washington) on benign biopsies from 98 patients. Biopsies were obtained from 4 groups that included 39 patients with first time negative biopsy (group 1), 24 patients with persistently negative biopsies (group 2), 8 patients with initially negative biopsies who were subsequently diagnosed with prostate carcinoma (group 3) and negative biopsies obtained from 27 cases where other concurrent biopsies contained prostate carcinoma (group 4). Early prostate cancer antigen staining was assessed by 2 of the authors who were blind to the group of the examined sections. Staining intensity (range 0 to 3) and extent (range 1 to 3) scores were assigned. The presence of intensity 3 staining in any of the blocks of a biopsy specimen was considered as positive for early prostate cancer antigen for the primary outcome in the statistical analysis. In addition, as secondary outcomes we evaluated the data using the proportion of blocks with intensity 3 early prostate cancer antigen staining, the mean of the product of staining intensity and staining extent of all blocks within a biopsy, and the mean of the product of intensity 3 staining and extent. Primary outcome analysis revealed the proportion of early prostate cancer antigen positivity to be highest in group 3 (6 of 8, 75%) and lowest in group 2 (7 of 24, 29%, p=0.04 for differences among groups). A relatively higher than expected proportion of early prostate cancer antigen positivity was present in

Co-ordinate expression of the pre-T-cell receptor complex and a novel immature thymocyte-specific antigen, IMT-1, during thymocyte development.

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Tong, J J; Kishi, H; Nagata, T; Muraguchi, A

1999-01-01

Previously we described a monoclonal antibody (mAb) that reacted with a cell-surface antigen, immature thymocyte antigen-1 (IMT-1), which is expressed on thymocytes of late CD4- CD8- (double negative) to early CD4+ CD8+ (double positive) differentiation stages. In this study, we investigated the expression of IMT-1 on various cell lineages in thymus as well as in peripheral lymphoid organs. We found that IMT-1 is expressed on T-cell receptor (TCR)-betalo and TCR-deltalo thymocytes, but not on TCR-betahi, TCR-deltahi or natural killer (NK)1.1+ thymocytes, or on peripheral alpha beta or gamma delta T cells. We also investigated the kinetics of expression of IMT-1 during fetal thymocyte development and compared it with the expression of the pre-TCR complex, comprising CD3, pre-TCR-alpha (pTalpha) and TCR-beta. We found that expression of both was similar, starting at day 14.5 of gestation, peaking on day 16.5 and gradually decreasing thereafter. Furthermore, the expression of both IMT-1 and pTalpha was drastically reduced when DN thymocytes in recombination activating gene (RAG)-2-/- mice were challenged in vivo with anti-CD3 mAb. These results indicate that IMT-1 is expressed on not only immature thymocytes of alpha beta T-cell lineage but also on those of gamma delta T-cell lineage, and that the expression of IMT-1 and the pre-TCR complex is co-ordinately regulated during the alpha beta lineage thymocyte development.

Nuclear localization of Merkel cell polyomavirus large T antigen in Merkel cell carcinoma

International Nuclear Information System (INIS)

Nakamura, Tomoyuki; Sato, Yuko; Watanabe, Daisuke; Ito, Hideki; Shimonohara, Nozomi; Tsuji, Takahiro; Nakajima, Noriko; Suzuki, Yoshio; Matsuo, Koma; Nakagawa, Hidemi; Sata, Tetsutaro; Katano, Harutaka

2010-01-01

To clarify whether mutations in the large T gene encoded by Merkel cell polyomavirus affect the expression and function of large T antigen in Merkel cell carcinoma cases, we investigated the expression of large T antigen in vitro and in vivo. Immunohistochemistry using a rabbit polyclonal antibody revealed that large T antigen was expressed in the nuclei of Merkel cell carcinoma cells with Merkel cell polyomavirus infection. Deletion mutant analyses identified an Arg-Lys-Arg-Lys sequence (amino acids 277-280) as a nuclear localization signal in large T antigen. Sequence analyses revealed that there were no mutations in the nuclear localization signal in any of the eleven Merkel cell polyomavirus strains examined. Furthermore, stop codons were not observed in the upstream of the nuclear localization signal in any of the Merkel cell carcinoma cases examined. These data suggest that the nuclear localization signal is highly conserved and functional in Merkel cell carcinoma cases.

Immunohistochemical study of p53 and proliferating cell nuclear antigen expression in odontogenic keratocyst and periapical cyst.

Science.gov (United States)

Sajeevan, Thara Purath; Saraswathi, Tillai Rajasekaran; Ranganathan, Kannan; Joshua, Elizabeth; Rao, Uma Devi K

2014-07-01

p53 protein is a product of p53 gene, which is now classified as a tumor suppressor gene. The gene is a frequent target for mutation, being seen as a common step in the pathogenesis of many human cancers. Proliferating cell nuclear antigen (PCNA) is an auxiliary protein of DNA polymerase delta and plays a critical role in initiation of cell proliferation. The aim of this study is to assess and compare the expression of p53 and PCNA in lining epithelium of odontogenic keratocyst (OKC) and periapical cyst (PA). A total of 20 cases comprising 10 OKC and 10 PA were included in retrospective study. Three paraffin section of 4 μm were cut, one was used for routine hematoxylin and eosin stain, while the other two were used for immunohistochemistry. Statistical analysis was performed using Chi-square test. The level of staining and intensity were assessed in all these cases. OKC showed PCNA expression in all cases (100%), whereas in perapical cyst only 60% of cases exhibited PCNA staining. (1) OKC showed p53 expression in 6 cases (60%) whereas in PA only 10% of the cases exhibited p53 staining. Chi-square test showed PCNA staining intensity was more significant than p53 in OKC. (2) The staining intensity of PA using p53, PCNA revealed that PCNA stating intensity was more significant than p53. OKC shows significant proliferative activity than PA using PCNA and p53. PCNA staining was more intense when compared with p53 in both OKC and PA.

Use of JH4 joining segment gene by an anti-arsonate antibody that bears the major A-strain cross-reactive idiotype but displays diminished antigen binding.

Science.gov (United States)

Slaughter, C A; Jeske, D J; Kuziel, W A; Milner, E C; Capra, J D

1984-06-01

One of the antibody families utilized by the A/J mouse in its response to p-azophenylarsonate (Ars) is characterized by the expression of the major anti-arsonate cross-reactive idiotype (CRI) of the A strain. This family has been termed the Ars-A family. A hybridoma antibody (HP 101F11 ) obtained after immunization of an A/J mouse with Ars was identified initially as displaying the CRI, but was subsequently found to bind antigen at a level much lower than most members of the Ars-A family. The results of binding studies suggested that HP 101F11 possesses reduced avidity for antigen. When isolated light and heavy chains were allowed to recombine with the heavy and light chains of a strongly antigen-binding, strongly CRI-positive antibody of the Ars-A family (HP 93G7 ), the low level of antigen binding by HP 101F11 was found to be due to a structurally variant heavy chain. Whereas antibodies of the Ars-A family with normal avidity for antigen had been shown to use the JH2 joining segment gene, amino acid sequence analysis of HP 101F11 revealed that this antibody has a JH segment with a sequence identical to that encoded by a portion of a different JH gene, JH4 . The implication that 101F11 uses the JH4 gene instead of JH2 was supported by the observation that the productively rearranged gene is associated with an Eco R1 restriction fragment 0.95 Kb smaller than the corresponding fragments of Ars-A hybridomas with normal avidity for antigen. The size difference of 0.95 Kb corresponds exactly to the known distance between the JH2 and JH4 genes in BALB/c germline DNA. In addition to the structural differences immediately attributable to the use of JH4 , HP 101F11 has shown an amino acid interchange in the DH segment, and a single amino acid deletion at the DH-JH boundary. These results show that variation among members of the Ars-A family in the DH and/or JH segments provides alternative structural forms of Ars-A antibodies upon which selective processes can operate

Identification of genes expressed in cultures of E. coli lysogens carrying the Shiga toxin-encoding prophage Φ24B

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Riley Laura M

2012-03-01

Full Text Available Abstract Background Shigatoxigenic E. coli are a global and emerging health concern. Shiga toxin, Stx, is encoded on the genome of temperate, lambdoid Stx phages. Genes essential for phage maintenance and replication are encoded on approximately 50% of the genome, while most of the remaining genes are of unknown function nor is it known if these annotated hypothetical genes are even expressed. It is hypothesized that many of the latter have been maintained due to positive selection pressure, and that some, expressed in the lysogen host, have a role in pathogenicity. This study used Change Mediated Antigen Technology (CMAT™ and 2D-PAGE, in combination with RT-qPCR, to identify Stx phage genes that are expressed in E. coli during the lysogenic cycle. Results Lysogen cultures propagated for 5-6 hours produced a high cell density with a low proportion of spontaneous prophage induction events. The expression of 26 phage genes was detected in these cultures by differential 2D-PAGE of expressed proteins and CMAT. Detailed analyses of 10 of these genes revealed that three were unequivocally expressed in the lysogen, two expressed from a known lysogenic cycle promoter and one uncoupled from the phage regulatory network. Conclusion Propagation of a lysogen culture in which no cells at all are undergoing spontaneous lysis is impossible. To overcome this, RT-qPCR was used to determine gene expression profiles associated with the growth phase of lysogens. This enabled the definitive identification of three lambdoid Stx phage genes that are expressed in the lysogen and seven that are expressed during lysis. Conservation of these genes in this phage genome, and other Stx phages where they have been identified as present, indicates their importance in the phage/lysogen life cycle, with possible implications for the biology and pathogenicity of the bacterial host.

Sequential appearance of thymocyte subpopulations and T cell antigen receptor gene messages in the mouse thymus after sublethal irradiation

International Nuclear Information System (INIS)

Tomooka, S.; Matsuzaki, G.; Kishihara, K.; Tanaka, K.; Yoshikai, Y.; Taniguchi, K.; Himeno, K.; Nomoto, K.

1987-01-01

The sequential differentiation patterns of thymocyte were observed with cell surface phenotypes and the expression of T cell antigen receptor in 800 rad irradiated adult mice. Thymus was severely reduced in size and cell number by day 5 after whole body irradiation and rapidly recovered from day 7 to day 14. Surface marker analysis on day 5 after irradiation showed thymocytes with Thy-1low L3T4+/Lyt-2- dominantly existed and suggested that these cells were radioresistant-survived cells. On the other hand, thymocytes on day 7 were composed of a large number of Thy-1high L3T4+/Lyt-2+ blast-like cells and a relatively high proportion of Thy-1high L3T4-/Lyt-2- cells which expressed a large amount of gamma-chain gene messages but scarcely any alpha- and beta-chain gene messages similar to the fetal thymocytes. On day 14, thymocytes were composed mostly of Thy-1high H-2low L3T4+/Lyt-2+ subpopulation which expressed a remarkably low level of gamma-chain gene messages, and high levels of alpha- and beta-chain transcripts analogous to those of normal adult thymus. Taken together, intrathymic radioresistent stem cells for T thymocytes seem to proliferate and differentiate after irradiation with the same pattern as was seen in a fetal thymus development

Microarray analysis of differentially expressed genes and their functions in omental visceral adipose tissues of pregnant women with vs. without gestational diabetes mellitus

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Qian, Yuan; Sun, Hao; Xiao, Hongli; Ma, Meirun; Xiao, Xue; Qu, Qinzai

2017-01-01

Increasing evidence has shown that insulin resistance in omental visceral adipose tissue (OVAT) is a characteristic of gestational diabetes mellitus (GDM). The present study aimed to identify differentially expressed genes (DEGs) and their associated functions and pathways involved in the pathogenesis of GDM by comparing the expression profiles of OVATs obtained from pregnant Chinese women with and without GDM during caesarian section. A total of 935 DEGs were identified, including 450 downregulated and 485 upregulated genes. In the gene ontology category cellular components, the DEGs were predominantly associated with functions of the extracellular region, while receptor binding was predominant in the molecular function category and biological process terms included antigen processing and presentation, extracellular matrix organization, positive regulation of cell-substrate adhesion, response to nutrients and response to dietary excess. Functional enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment were performed and a functional interaction network was constructed. Functions of downregulated genes included antigen processing and presentation as well as cell adhesion molecules, while those of upregulated genes included transforming growth factor (TGF)-β-signaling, focal adhesion, phosphoinositide-3 kinase-Akt-signaling, P53 signaling, extracellular matrix-receptor interaction and regulation of actin cytoskeleton pathway. The five main pathways associated with GDM were antigen processing and presentation, cell adhesion molecules, Type 1 diabetes mellitus, natural killer cell-mediated cytotoxicity and TGF-β signaling. These pathways were included in the KEGG pathway categories of ‘signaling molecules and interaction’, ‘immune system’ and ‘inflammatory response’, suggesting that these processes are involved in GDM. The results of the present study enhanced the present understanding of the mechanisms associated with insulin

De nonklassiske humant leukocyt-antigen (HLA)-vaevstyper--fra implantation til transplantation

DEFF Research Database (Denmark)

Hviid, Thomas Vauvert F

2006-01-01

), other functional HLA genes have been detected, the so-called non-classical HLA class Ib genes: HLA-E, -G and -F. They resemble the HLA class Ia antigens in many ways, but several major differences have been described. They are almost monomorphic and generally have a restricted pattern of expression. One...... has a role in implantation. A very strong expression of HLA-G is observed in the invasive trophoblast cells in the placenta. HLA-G may be involved in certain complications of pregnancy and the genetic predisposition to these. Finally, HLA-G expression has been associated with a reduced risk...

Characterization of differentially expressed genes using high-dimensional co-expression networks

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Coelho Goncalves de Abreu, Gabriel; Labouriau, Rodrigo S.

2010-01-01

We present a technique to characterize differentially expressed genes in terms of their position in a high-dimensional co-expression network. The set-up of Gaussian graphical models is used to construct representations of the co-expression network in such a way that redundancy and the propagation...... that allow to make effective inference in problems with high degree of complexity (e.g. several thousands of genes) and small number of observations (e.g. 10-100) as typically occurs in high throughput gene expression studies. Taking advantage of the internal structure of decomposable graphical models, we...... construct a compact representation of the co-expression network that allows to identify the regions with high concentration of differentially expressed genes. It is argued that differentially expressed genes located in highly interconnected regions of the co-expression network are less informative than...

Regulation of eucaryotic gene expression

Energy Technology Data Exchange (ETDEWEB)

Brent, R.; Ptashne, M.S

1989-05-23

This patent describes a method of regulating the expression of a gene in a eucaryotic cell. The method consists of: providing in the eucaryotic cell, a peptide, derived from or substantially similar to a peptide of a procaryotic cell able to bind to DNA upstream from or within the gene, the amount of the peptide being sufficient to bind to the gene and thereby control expression of the gene.

[Prokaryotic expression of vp3 gene of Muscovy duck parvovirus, and its antiserum preparation for detection of virus multiplication].

Science.gov (United States)

Huang, Yu; Zhu, Yumin; Dong, Shijuan; Yu, Ruisong; Zhang, Yuanshu; Li, Zhen

2015-01-01

New epidemic broke out in recent year which was suspected to be caused by variant Muscovy duck parvovirus (MDPV). For this reason, new MDPV detection methods are needed for the new virus strains. In this study, a pair of primers were designed according to the full-length genome of MDPV strain SAAS-SHNH, which were identified in 2012, and were used to amplify the vp3 gene of MDPV by polymerase chain reaction. After being sequenced, the vp3 gene was subcloned into the prokaryotic expression vector PET28a. The recombinant plasmid was transformed into E. coli BL21 and induced with IPTG. SDS-PAGE and Western blotting analysis showed the MDPV vp3 gene was successfully expressed. After being purified by Ni2+ affinity chromatography system, the recombinant protein was used as antigen to immunize rabbits to obtain antiserum. Western blotting analysis showed that the acquired antiserum could react specifically with VP3 protein of J3D6 strain and MDPV vaccine strain. The antiserum could also be used for detection of cultured MDPV from primary duck embryo fibroblasts by immune fluorescence assay (IFA). It could be concluded that the VP3 protein and its antibody prepared in the research could be used for detection of VP3 antiserum and antigen respectively.

Sperm associated antigen 9 (SPAG9) expression and humoral response in benign and malignant salivary gland tumors

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Agarwal, Sumit; Parashar, Deepak; Gupta, Namita; Jagadish, Nirmala; Thakar, Alok; Suri, Vaishali; Kumar, Rajive; Gupta, Anju; Ansari, Abdul S; Lohiya, Nirmal Kumar; Suri, Anil

2015-01-01

Salivary gland cancers are highly aggressive epithelial tumor associated with metastatic potential and high mortality. The tumors are biologically diverse and are of various histotypes. Besides, the detection and diagnosis is a major problem of salivary gland cancer for available treatment modalities. In the present study, we have investigated the association of sperm associated antigen 9 (SPAG9) expression with salivary gland tumor (SGT). Clinical specimens of benign (n = 16) and malignant tumors (n = 86) were examined for the SPAG9 expression. In addition, the sera and adjacent non-cancerous tissues (n = 72) from available patients were obtained. Our in situ RNA hybridization and immunohistochemistry (IHC) analysis revealed significant difference (p = 0.0001) in SPAG9 gene and protein expression in benign (63%) and malignant tumor (84%) specimens. Further, significant association was also observed between SPAG9 expression and malignant tumors (P = 0.05). A cut-off value of >10% cells expressing SPAG9 protein designated as positive in IHC, predicted presence of malignant SGT with 83.72% sensitivity, 100% specificity, 100% PPV and 83.72% NPV. Humoral response against SPAG9 protein was generated in 68% of SGT patients. A cut-off value of 0.212 OD for anti-SPAG9 antibodies in ELISA predicted presence of malignant SGT with 69.23% sensitivity, 100% specificity, 100% PPV and 78.94% NPV. Collectively, our data suggests that the majority of SGT show significant difference and association among benign and malignant tumors for SPAG9 gene and protein expression and also exhibit humoral response against SPAG9 protein. Hence, SPAG9 may be developed as a biomarker for detection and diagnosis of salivary gland tumors. PMID:25941602

Strains of Sarcocystis neurona exhibit differences in their surface antigens, including the absence of the major surface antigen SnSAG1.

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Howe, Daniel K; Gaji, Rajshekhar Y; Marsh, Antoinette E; Patil, Bhagyashree A; Saville, William J; Lindsay, David S; Dubey, J P; Granstrom, David E

2008-05-01

A gene family of surface antigens is expressed by merozoites of Sarcocystis neurona, the primary cause of equine protozoal myeloencephalitis (EPM). These surface proteins, designated SnSAGs, are immunodominant and therefore excellent candidates for development of EPM diagnostics or vaccines. Prior work had identified an EPM isolate lacking the major surface antigen SnSAG1, thus suggesting there may be some diversity in the SnSAGs expressed by different S. neurona isolates. Therefore, a bioinformatic, molecular and immunological study was conducted to assess conservation of the SnSAGs. Examination of an expressed sequence tag (EST) database revealed several notable SnSAG polymorphisms. In particular, the EST information implied that the EPM strain SN4 lacked the major surface antigen SnSAG1. The absence of this surface antigen from the SN4 strain was confirmed by both Western blot and Southern blot. To evaluate SnSAG polymorphisms in the S. neurona population, 14 strains were examined by Western blots using monospecific polyclonal antibodies against the four described SnSAGs. The results of these analyses demonstrated that SnSAG2, SnSAG3, and SnSAG4 are present in all 14 S. neurona strains tested, although some variance in SnSAG4 was observed. Importantly, SnSAG1 was not detected in seven of the strains, which included isolates from four cases of EPM and a case of fatal meningoencephalitis in a sea otter. Genetic analyses by PCR using gene-specific primers confirmed the absence of the SnSAG1 locus in six of these seven strains. Collectively, the data indicated that there is heterogeneity in the surface antigen composition of different S. neurona isolates, which is an important consideration for development of serological tests and prospective vaccines for EPM. Furthermore, the diversity reported herein likely extends to other phenotypes, such as strain virulence, and may have implications for the phylogeny of the various Sarcocystis spp. that undergo sexual stages

Low cost tuberculosis vaccine antigens in capsules: expression in chloroplasts, bio-encapsulation, stability and functional evaluation in vitro.

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Priya Saikumar Lakshmi

Full Text Available Tuberculosis (TB caused by Mycobacterium tuberculosis is one of the leading fatal infectious diseases. The development of TB vaccines has been recognized as a major public health priority by the World Health Organization. In this study, three candidate antigens, ESAT-6 (6 kDa early secretory antigenic target and Mtb72F (a fusion polyprotein from two TB antigens, Mtb32 and Mtb39 fused with cholera toxin B-subunit (CTB and LipY (a cell wall protein were expressed in tobacco and/or lettuce chloroplasts to facilitate bioencapsulation/oral delivery. Site-specific transgene integration into the chloroplast genome was confirmed by Southern blot analysis. In transplastomic leaves, CTB fusion proteins existed in soluble monomeric or multimeric forms of expected sizes and their expression levels varied depending upon the developmental stage and time of leaf harvest, with the highest-level of accumulation in mature leaves harvested at 6PM. The CTB-ESAT6 and CTB-Mtb72F expression levels reached up to 7.5% and 1.2% of total soluble protein respectively in mature tobacco leaves. Transplastomic CTB-ESAT6 lettuce plants accumulated up to 0.75% of total leaf protein. Western blot analysis of lyophilized lettuce leaves stored at room temperature for up to six months showed that the CTB-ESAT6 fusion protein was stable and preserved proper folding, disulfide bonds and assembly into pentamers for prolonged periods. Also, antigen concentration per gram of leaf tissue was increased 22 fold after lyophilization. Hemolysis assay with purified CTB-ESAT6 protein showed partial hemolysis of red blood cells and confirmed functionality of the ESAT-6 antigen. GM1-binding assay demonstrated that the CTB-ESAT6 fusion protein formed pentamers to bind with the GM1-ganglioside receptor. The expression of functional Mycobacterium tuberculosis antigens in transplastomic plants should facilitate development of a cost-effective and orally deliverable TB booster vaccine with potential

Low cost tuberculosis vaccine antigens in capsules: expression in chloroplasts, bio-encapsulation, stability and functional evaluation in vitro.

Science.gov (United States)

Lakshmi, Priya Saikumar; Verma, Dheeraj; Yang, Xiangdong; Lloyd, Bethany; Daniell, Henry

2013-01-01

Tuberculosis (TB) caused by Mycobacterium tuberculosis is one of the leading fatal infectious diseases. The development of TB vaccines has been recognized as a major public health priority by the World Health Organization. In this study, three candidate antigens, ESAT-6 (6 kDa early secretory antigenic target) and Mtb72F (a fusion polyprotein from two TB antigens, Mtb32 and Mtb39) fused with cholera toxin B-subunit (CTB) and LipY (a cell wall protein) were expressed in tobacco and/or lettuce chloroplasts to facilitate bioencapsulation/oral delivery. Site-specific transgene integration into the chloroplast genome was confirmed by Southern blot analysis. In transplastomic leaves, CTB fusion proteins existed in soluble monomeric or multimeric forms of expected sizes and their expression levels varied depending upon the developmental stage and time of leaf harvest, with the highest-level of accumulation in mature leaves harvested at 6PM. The CTB-ESAT6 and CTB-Mtb72F expression levels reached up to 7.5% and 1.2% of total soluble protein respectively in mature tobacco leaves. Transplastomic CTB-ESAT6 lettuce plants accumulated up to 0.75% of total leaf protein. Western blot analysis of lyophilized lettuce leaves stored at room temperature for up to six months showed that the CTB-ESAT6 fusion protein was stable and preserved proper folding, disulfide bonds and assembly into pentamers for prolonged periods. Also, antigen concentration per gram of leaf tissue was increased 22 fold after lyophilization. Hemolysis assay with purified CTB-ESAT6 protein showed partial hemolysis of red blood cells and confirmed functionality of the ESAT-6 antigen. GM1-binding assay demonstrated that the CTB-ESAT6 fusion protein formed pentamers to bind with the GM1-ganglioside receptor. The expression of functional Mycobacterium tuberculosis antigens in transplastomic plants should facilitate development of a cost-effective and orally deliverable TB booster vaccine with potential for long

Infrequent Expression of the Cancer-Testis Antigen, PASD1, in Ovarian Cancer

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Ghazala Khan

2015-01-01

Full Text Available Ovarian cancer is very treatable in the early stages of disease; however, it is usually detected in the later stages, at which time, treatment is no longer as effective. If discovered early (Stage I, there is a 90% chance of five-year survival. Therefore, it is imperative that early-stage biomarkers are identified to enhance the early detection of ovarian cancer. Cancer-testis antigens (CTAs, such as Per ARNT SIM (PAS domain containing 1 (PASD1, are unique in that their expression is restricted to immunologically restricted sites, such as the testis and placenta, which do not express MHC class I, and cancer, making them ideally positioned to act as targets for immunotherapy as well as potential biomarkers for cancer detection where expressed. We examined the expression of PASD1a and b in a number of cell lines, as well as eight healthy ovary samples, eight normal adjacent ovarian tissues, and 191 ovarian cancer tissues, which were predominantly stage I ( n = 164 and stage II ( n = 14 disease. We found that despite the positive staining of skin cancer, only one stage Ic ovarian cancer patient tissue expressed PASD1a and b at detectable levels. This may reflect the predominantly stage I ovarian cancer samples examined. To examine the restriction of PASD1 expression, we examined endometrial tissue arrays and found no expression in 30 malignant tumor tissues, 23 cases of hyperplasia, or 16 normal endometrial tissues. Our study suggests that the search for a single cancer-testes antigen/biomarker that can detect early ovarian cancer must continue.

Hepatitis B surface antigen (HBsAg) expression in plant cell culture: Kinetics of antigen accumulation in batch culture and its intracellular form.

Science.gov (United States)

Smith, Mark L; Mason, Hugh S; Shuler, Michael L

2002-12-30

The production of edible vaccines in transgenic plants and plant cell culture may be improved through a better understanding of antigen processing and assembly. The hepatitis B surface antigen (HBsAg) was chosen for study because it undergoes substantial and complex post-translational modifications, which are necessary for its immunogenicity. This antigen was expressed in soybean (Glycine max L. Merr. cv Williams 82) and tobacco NT1 (Nicotiana tabacum L.) cell suspension cultures, and HBsAg production in batch culture was characterized. The plant-derived antigen consisted predominantly of disulfide cross-linked HBsAg protein (p24(s)) dimers, which were all membrane associated. Similar to yeast, the plant-expressed HBsAg was retained intracellularly. The maximal HBsAg titers were obtained with soybean suspension cultures (20-22 mg/L) with titers in tobacco cultures being approximately 10-fold lower. For soybean cells, electron microscopy and immunolocalization demonstrated that all the HBsAg was localized to the endoplasmic reticulum (ER) and provoked dilation and proliferation of the ER network. Sucrose gradient analysis of crude extracts showed that HBsAg had a complex size distribution uncharacteristic of the antigen's normal structure of uniform 22-nm virus-like particles. The extent of authentic epitope formation was assessed by comparing total p24(s) synthesized to that reactive by polyclonal and monoclonal immunoassays. Depending on culture age, between 40% and 100% of total p24(s) was polyclonal antibody reactive whereas between 6% and 37% was recognized by a commercial monoclonal antibody assay. Possible strategies to increase HBsAg production and improve post-translational processing are discussed. Copyright 2002 Wiley Periodicals, Inc.

Expression of Immunoglobulin Receptors with Distinctive Features Indicating Antigen Selection by Marginal Zone B Cells from Human Spleen

Science.gov (United States)

Colombo, Monica; Cutrona, Giovanna; Reverberi, Daniele; Bruno, Silvia; Ghiotto, Fabio; Tenca, Claudya; Stamatopoulos, Kostas; Hadzidimitriou, Anastasia; Ceccarelli, Jenny; Salvi, Sandra; Boccardo, Simona; Calevo, Maria Grazia; De Santanna, Amleto; Truini, Mauro; Fais, Franco; Ferrarini, Manlio

2013-01-01

Marginal zone (MZ) B cells, identified as surface (s)IgMhighsIgDlowCD23low/−CD21+CD38− B cells, were purified from human spleens, and the features of their V(D)J gene rearrangements were investigated and compared with those of germinal center (GC), follicular mantle (FM) and switched memory (SM) B cells. Most MZ B cells were CD27+ and exhibited somatic hypermutations (SHM), although to a lower extent than SM B cells. Moreover, among MZ B-cell rearrangements, recurrent sequences were observed, some of which displayed intraclonal diversification. The same diversifying sequences were detected in very low numbers in GC and FM B cells and only when a highly sensitive, gene-specific polymerase chain reaction was used. This result indicates that MZ B cells could expand and diversify in situ and also suggested the presence of a number of activation-induced cytidine deaminase (AID)-expressing B cells in the MZ. The notion of antigen-driven expansion/selection in situ is further supported by the VH CDR3 features of MZ B cells with highly conserved amino acids at specific positions and by the finding of shared (“stereotyped”) sequences in two different spleens. Collectively, the data are consistent with the notion that MZ B cells are a special subset selected by in situ antigenic stimuli. PMID:23877718

Antisense long noncoding RNAs regulate var gene activation in the malaria parasite Plasmodium falciparum.

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Amit-Avraham, Inbar; Pozner, Guy; Eshar, Shiri; Fastman, Yair; Kolevzon, Netanel; Yavin, Eylon; Dzikowski, Ron

2015-03-03

The virulence of Plasmodium falciparum, the causative agent of the deadliest form of human malaria, is attributed to its ability to evade human immunity through antigenic variation. These parasites alternate between expression of variable antigens, encoded by members of a multicopy gene family named var. Immune evasion through antigenic variation depends on tight regulation of var gene expression, ensuring that only a single var gene is expressed at a time while the rest of the family is maintained transcriptionally silent. Understanding how a single gene is chosen for activation is critical for understanding mutually exclusive expression but remains a mystery. Here, we show that antisense long noncoding RNAs (lncRNAs) initiating from var introns are associated with the single active var gene at the time in the cell cycle when the single var upstream promoter is active. We demonstrate that these antisense transcripts are incorporated into chromatin, and that expression of these antisense lncRNAs in trans triggers activation of a silent var gene in a sequence- and dose-dependent manner. On the other hand, interference with these lncRNAs using complement peptide nucleic acid molecules down-regulated the active var gene, erased the epigenetic memory, and induced expression switching. Altogether, our data provide evidence that these antisense lncRNAs play a key role in regulating var gene activation and mutually exclusive expression.

Interleukins 1alpha and 1beta secreted by some melanoma cell lines strongly reduce expression of MITF-M and melanocyte differentiation antigens.

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Kholmanskikh, Olga; van Baren, Nicolas; Brasseur, Francis; Ottaviani, Sabrina; Vanacker, Julie; Arts, Nathalie; van der Bruggen, Pierre; Coulie, Pierre; De Plaen, Etienne

2010-10-01

We report that melanoma cell lines expressing the interleukin-1 receptor exhibit 4- to 10-fold lower levels of mRNA of microphthalmia-associated transcription factor (MITF-M) when treated with interleukin-1beta. This effect is NF-kappaB and JNK-dependent. MITF-M regulates the expression of melanocyte differentiation genes such as MLANA, tyrosinase and gp100, which encode antigens recognized on melanoma cells by autologous cytolytic T lymphocytes. Accordingly, treating some melanoma cells with IL-1beta reduced by 40-100% their ability to activate such antimelanoma cytolytic T lymphocytes. Finally, we observed large amounts of biologically active IL-1alpha or IL-1beta secreted by two melanoma cell lines that did not express MITF-M, suggesting an autocrine MITF-M downregulation. We estimate that approximately 13% of melanoma cell lines are MITF-M-negative and secrete IL-1 cytokines. These results indicate that the repression of melanocyte-differentiation genes by IL-1 produced by stromal cells or by tumor cells themselves may represent an additional mechanism of melanoma immune escape.

Different Temporal Effects of Ebola Virus VP35 and VP24 Proteins on Global Gene Expression in Human Dendritic Cells.

Science.gov (United States)

Ilinykh, Philipp A; Lubaki, Ndongala M; Widen, Steven G; Renn, Lynnsey A; Theisen, Terence C; Rabin, Ronald L; Wood, Thomas G; Bukreyev, Alexander

2015-08-01

Ebola virus (EBOV) causes a severe hemorrhagic fever with a deficient immune response, lymphopenia, and lymphocyte apoptosis. Dendritic cells (DC), which trigger the adaptive response, do not mature despite EBOV infection. We recently demonstrated that DC maturation is unblocked by disabling the innate response antagonizing domains (IRADs) in EBOV VP35 and VP24 by the mutations R312A and K142A, respectively. Here we analyzed the effects of VP35 and VP24 with the IRADs disabled on global gene expression in human DC. Human monocyte-derived DC were infected by wild-type (wt) EBOV or EBOVs carrying the mutation in VP35 (EBOV/VP35m), VP24 (EBOV/VP24m), or both (EBOV/VP35m/VP24m). Global gene expression at 8 and 24 h was analyzed by deep sequencing, and the expression of interferon (IFN) subtypes up to 5 days postinfection was analyzed by quantitative reverse transcription-PCR (qRT-PCR). wt EBOV induced a weak global gene expression response, including markers of DC maturation, cytokines, chemokines, chemokine receptors, and multiple IFNs. The VP35 mutation unblocked the expression, resulting in a dramatic increase in expression of these transcripts at 8 and 24 h. Surprisingly, DC infected with EBOV/VP24m expressed lower levels of many of these transcripts at 8 h after infection, compared to wt EBOV. In contrast, at 24 h, expression of the transcripts increased in DC infected with any of the three mutants, compared to wt EBOV. Moreover, sets of genes affected by the two mutations only partially overlapped. Pathway analysis demonstrated that the VP35 mutation unblocked pathways involved in antigen processing and presentation and IFN signaling. These data suggest that EBOV IRADs have profound effects on the host adaptive immune response through massive transcriptional downregulation of DC. This study shows that infection of DC with EBOV, but not its mutant forms with the VP35 IRAD and/or VP24 IRAD disabled, causes a global block in expression of host genes. The temporal

PfSETvs methylation of histone H3K36 represses virulence genes in Plasmodium falciparum

DEFF Research Database (Denmark)

Jiang, Lubin; Mu, Jianbing; Zhang, Qingfeng

2013-01-01

The variant antigen Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1), which is expressed on the surface of P. falciparum-infected red blood cells, is a critical virulence factor for malaria. Each parasite has 60 antigenically distinct var genes that each code for a different PfEMP1...... parasite nuclei and their expression as proteins on the surface of individual infected red blood cells. PfSETvs-dependent H3K36me3 is present along the entire gene body, including the transcription start site, to silence var genes. With low occupancy of PfSETvs at both the transcription start site of var...... protein. During infection the clonal parasite population expresses only one gene at a time before switching to the expression of a new variant antigen as an immune-evasion mechanism to avoid the host antibody response. The mechanism by which 59 of the 60 var genes are silenced remains largely unknown...

Gene Expression Analysis of Plum pox virus (Sharka) Susceptibility/Resistance in Apricot (Prunus armeniaca L.).

Science.gov (United States)

Rubio, Manuel; Ballester, Ana Rosa; Olivares, Pedro Manuel; Castro de Moura, Manuel; Dicenta, Federico; Martínez-Gómez, Pedro

2015-01-01

RNA-Seq has proven to be a very powerful tool in the analysis of the Plum pox virus (PPV, sharka disease)/Prunus interaction. This technique is an important complementary tool to other means of studying genomics. In this work an analysis of gene expression of resistance/susceptibility to PPV in apricot is performed. RNA-Seq has been applied to analyse the gene expression changes induced by PPV infection in leaves from two full-sib apricot genotypes, "Rojo Pasión" and "Z506-7", resistant and susceptible to PPV, respectively. Transcriptomic analyses revealed the existence of more than 2,000 genes related to the pathogen response and resistance to PPV in apricot. These results showed that the response to infection by the virus in the susceptible genotype is associated with an induction of genes involved in pathogen resistance such as the allene oxide synthase, S-adenosylmethionine synthetase 2 and the major MLP-like protein 423. Over-expression of the Dicer protein 2a may indicate the suppression of a gene silencing mechanism of the plant by PPV HCPro and P1 PPV proteins. On the other hand, there were 164 genes involved in resistance mechanisms that have been identified in apricot, 49 of which are located in the PPVres region (scaffold 1 positions from 8,050,804 to 8,244,925), which is responsible for PPV resistance in apricot. Among these genes in apricot there are several MATH domain-containing genes, although other genes inside (Pleiotropic drug resistance 9 gene) or outside (CAP, Cysteine-rich secretory proteins, Antigen 5 and Pathogenesis-related 1 protein; and LEA, Late embryogenesis abundant protein) PPVres region could also be involved in the resistance.

Inferring gene expression dynamics via functional regression analysis

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Leng Xiaoyan

2008-01-01

Full Text Available Abstract Background Temporal gene expression profiles characterize the time-dynamics of expression of specific genes and are increasingly collected in current gene expression experiments. In the analysis of experiments where gene expression is obtained over the life cycle, it is of interest to relate temporal patterns of gene expression associated with different developmental stages to each other to study patterns of long-term developmental gene regulation. We use tools from functional data analysis to study dynamic changes by relating temporal gene expression profiles of different developmental stages to each other. Results We demonstrate that functional regression methodology can pinpoint relationships that exist between temporary gene expression profiles for different life cycle phases and incorporates dimension reduction as needed for these high-dimensional data. By applying these tools, gene expression profiles for pupa and adult phases are found to be strongly related to the profiles of the same genes obtained during the embryo phase. Moreover, one can distinguish between gene groups that exhibit relationships with positive and others with negative associations between later life and embryonal expression profiles. Specifically, we find a positive relationship in expression for muscle development related genes, and a negative relationship for strictly maternal genes for Drosophila, using temporal gene expression profiles. Conclusion Our findings point to specific reactivation patterns of gene expression during the Drosophila life cycle which differ in characteristic ways between various gene groups. Functional regression emerges as a useful tool for relating gene expression patterns from different developmental stages, and avoids the problems with large numbers of parameters and multiple testing that affect alternative approaches.

ST6GalNAc-I controls expression of sialyl-Tn antigen in gastrointestinal tissues

DEFF Research Database (Denmark)

Marcos, Nuno T; Bennett, Eric Paul; Gomes, Joana

2011-01-01

-Tn biosynthesis. We developed novel monoclonal antibodies specific for ST6GalNAc-I and evaluated its expression in gastrointestinal tissues. ST6GalNAc-I was detected in normal colon mucosa co-localized with O-acetylated sialyl-Tn. Expression was largely unaltered in colorectal adenocarcinomas. In contrast, we......NAc-I as the major enzyme controlling the expression of cancer-associated sialyl-Tn antigen in gastrointestinal tissues....

Synthetic promoter libraries- tuning of gene expression

DEFF Research Database (Denmark)

Hammer, Karin; Mijakovic, Ivan; Jensen, Peter Ruhdal

2006-01-01

knockout and strong overexpression. However, applications such as metabolic optimization and control analysis necessitate a continuous set of expression levels with only slight increments in strength to cover a specific window around the wildtype expression level of the studied gene; this requirement can......The study of gene function often requires changing the expression of a gene and evaluating the consequences. In principle, the expression of any given gene can be modulated in a quasi-continuum of discrete expression levels but the traditional approaches are usually limited to two extremes: gene...

T-cell synapse formation depends on antigen recognition but not CD3 interaction: studies with TCR:ζ, a candidate transgene for TCR gene therapy.

Science.gov (United States)

Roszik, János; Sebestyén, Zsolt; Govers, Coen; Guri, Yakir; Szöor, Arpád; Pályi-Krekk, Zsuzsanna; Vereb, György; Nagy, Peter; Szöllosi, János; Debets, Reno

2011-05-01

T-cell receptors (TCRs) can be genetically modified to improve gene-engineered T-cell responses, a strategy considered critical for the success of clinical TCR gene therapy to treat cancers. TCR:ζ, which is a heterodimer of TCRα and β chains each coupled to complete human CD3ζ, overcomes issues of mis-pairing with endogenous TCR chains, shows high surface expression and mediates antigen-specific T-cell functions in vitro. In the current study, we further characterized TCR:ζ in gene-engineered T cells and assessed whether this receptor is able to interact with surface molecules and drive correct synapse formation in Jurkat T cells. The results showed that TCR:ζ mediates the formation of synaptic areas with antigen-positive target cells, interacts closely with CD8α and MHC class I (MHCI), and co-localizes with CD28, CD45 and lipid rafts, similar to WT TCR. TCR:ζ did not closely associate with endogenous CD3ε, despite its co-presence in immune synapses, and TCR:ζ showed enhanced synaptic accumulation in T cells negative for surface-expressed TCR molecules. Notably, synaptic TCR:ζ demonstrated lowered densities when compared with TCR in dual TCR T cells, a phenomenon that was related to both extracellular and intracellular CD3ζ domains present in the TCR:ζ molecule and responsible for enlarged synapse areas. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Why are parasite contingency genes often associated with telomeres?

Science.gov (United States)

Barry, J D; Ginger, M L; Burton, P; McCulloch, R

2003-01-01

Contingency genes are common in pathogenic microbes and enable, through pre-emptive mutational events, rapid, clonal switches in phenotype that are conducive to survival and proliferation in hosts. Antigenic variation, which is a highly successful survival strategy employed by eubacterial and eukaryotic pathogens, involves large repertoires of distinct contingency genes that are expressed differentially, enabling evasion of host acquired immunity. Most, but not all, antigenic variation systems make extensive use of subtelomeres. Study of model systems has shown that subtelomeres have unusual properties, including reversible silencing of genes mediated by proteins binding to the telomere, and engagement in ectopic recombination with other subtelomeres. There is a general theory that subtelomeric location confers a capacity for gene diversification through such recombination, although experimental evidence is that there is no increased mitotic recombination at such loci and that sequence homogenisation occurs. Possible benefits of subtelomeric location for pathogen contingency systems are reversible gene silencing, which could contribute to systems for gene switching and mutually exclusive expression, and ectopic recombination, leading to gene family diversification. We examine, in several antigenic variation systems, what possible benefits apply.

Upregulated Expression of a Unique Gene by Hepatitis B x Antigen Promotes Hepatocellular Growth and Tumorigenesis

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Zhaorui Lian

2003-05-01

Full Text Available Hepatitis B x antigen (HBxAg is a trans-activating protein that may be involved in hepatocarcinogenesis, although few natural effectors of HBxAg that participate in this process have been identified. To identify additional effectors, whole cell RNA isolated from HBxAg-positive and HBxAg-negative HepG2 cells were compared by polymerase chain reaction select cDNA subtraction, and one clone, upregulated gene, clone 11 (URG11, was chosen for further characterization. Elevated levels of URG11 mRNA and protein were observed in HBxAg-positive compared to HBxAg-negative HepG2 cells. Costaining was observed in infected liver (P<.01. URG11 stimulated cell growth in culture (P<.01, anchorage-independent growth in soft agar (P<.001, and accelerated tumor formation (P<.01, and yielded larger tumors (P<.02 in SCID mice injected subcutaneously with HepG2 cells. These data suggest that URG11 is a natural effector of HBxAg that may promote the development of hepatocellular carcinoma.

Expression of endogenous ALV antigens and susceptibility to subgroup E ALV in three strains of chickens (Endogenous avian C. type virus)

International Nuclear Information System (INIS)

Robinson, H.L.; Lamoreux, W.F.

1976-01-01

Cells from three strains of Kimber Farms chickens, K16, K18, and K28, have been characterized for the expression of endogenous avian C-type virus (ALV) antigens and for susceptibility to subgroup E ALV. In K16 the coordinate dominant expression of chick helper factor (chf ), the type specific antigen of endogenous subgroup E ALV, and the group specific (gs) antigen of ALV was observed. The expression of chf and gs antigen in K16 chf + gs + cells was similar to that observed in SPAFAS and H and N gs + cells. In K18 chf but not gs antigen was expressed. The expression of chf in K18 chf + gs + cells was distinct from that observed for the chf + gs + pedigrees but similar to that found in SPAFAS chf + gs - helper extremely high (h/sub E/) cells. Cells from K16 and K18 chickens were uniformly resistant to subgroup E ALV. In cells from K28 chickens, susceptibility to subgroup B virus correlated with susceptibility to subgroup E virus. The efficiency of plating of subgroup E virus on susceptible K28 cells with 10 3 --10 4 -fold lower on chf + cells than on chf - cells

Adaptive Evolution of Gene Expression in Drosophila.

Science.gov (United States)

Nourmohammad, Armita; Rambeau, Joachim; Held, Torsten; Kovacova, Viera; Berg, Johannes; Lässig, Michael

2017-08-08

Gene expression levels are important quantitative traits that link genotypes to molecular functions and fitness. In Drosophila, population-genetic studies have revealed substantial adaptive evolution at the genomic level, but the evolutionary modes of gene expression remain controversial. Here, we present evidence that adaptation dominates the evolution of gene expression levels in flies. We show that 64% of the observed expression divergence across seven Drosophila species are adaptive changes driven by directional selection. Our results are derived from time-resolved data of gene expression divergence across a family of related species, using a probabilistic inference method for gene-specific selection. Adaptive gene expression is stronger in specific functional classes, including regulation, sensory perception, sexual behavior, and morphology. Moreover, we identify a large group of genes with sex-specific adaptation of expression, which predominantly occurs in males. Our analysis opens an avenue to map system-wide selection on molecular quantitative traits independently of their genetic basis. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Adaptive Evolution of Gene Expression in Drosophila

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Armita Nourmohammad

2017-08-01

Full Text Available Gene expression levels are important quantitative traits that link genotypes to molecular functions and fitness. In Drosophila, population-genetic studies have revealed substantial adaptive evolution at the genomic level, but the evolutionary modes of gene expression remain controversial. Here, we present evidence that adaptation dominates the evolution of gene expression levels in flies. We show that 64% of the observed expression divergence across seven Drosophila species are adaptive changes driven by directional selection. Our results are derived from time-resolved data of gene expression divergence across a family of related species, using a probabilistic inference method for gene-specific selection. Adaptive gene expression is stronger in specific functional classes, including regulation, sensory perception, sexual behavior, and morphology. Moreover, we identify a large group of genes with sex-specific adaptation of expression, which predominantly occurs in males. Our analysis opens an avenue to map system-wide selection on molecular quantitative traits independently of their genetic basis.

Progesterone impairs antigen-non-specific immune protection by CD8 T memory cells via interferon-γ gene hypermethylation.

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Yao, Yushi; Li, Hui; Ding, Jie; Xia, Yixin; Wang, Lei

2017-11-01

Pregnant women and animals have increased susceptibility to a variety of intracellular pathogens including Listeria monocytogenes (LM), which has been associated with significantly increased level of sex hormones such as progesterone. CD8 T memory(Tm) cell-mediated antigen-non-specific IFN-γ responses are critically required in the host defense against LM. However, whether and how increased progesterone during pregnancy modulates CD8 Tm cell-mediated antigen-non-specific IFN-γ production and immune protection against LM remain poorly understood. Here we show in pregnant women that increased serum progesterone levels are associated with DNA hypermethylation of IFN-γ gene promoter region and decreased IFN-γ production in CD8 Tm cells upon antigen-non-specific stimulation ex vivo. Moreover, IFN-γ gene hypermethylation and significantly reduced IFN-γ production post LM infection in antigen-non-specific CD8 Tm cells are also observed in pregnant mice or progesterone treated non-pregnant female mice, which is a reversible phenotype following demethylation treatment. Importantly, antigen-non-specific CD8 Tm cells from progesterone treated mice have impaired anti-LM protection when adoptive transferred in either pregnant wild type mice or IFN-γ-deficient mice, and demethylation treatment rescues the adoptive protection of such CD8 Tm cells. These data demonstrate that increased progesterone impairs immune protective functions of antigen-non-specific CD8 Tm cells via inducing IFN-γ gene hypermethylation. Our findings thus provide insights into a new mechanism through which increased female sex hormone regulate CD8 Tm cell functions during pregnancy.

Progesterone impairs antigen-non-specific immune protection by CD8 T memory cells via interferon-γ gene hypermethylation.

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Yushi Yao

2017-11-01

Full Text Available Pregnant women and animals have increased susceptibility to a variety of intracellular pathogens including Listeria monocytogenes (LM, which has been associated with significantly increased level of sex hormones such as progesterone. CD8 T memory(Tm cell-mediated antigen-non-specific IFN-γ responses are critically required in the host defense against LM. However, whether and how increased progesterone during pregnancy modulates CD8 Tm cell-mediated antigen-non-specific IFN-γ production and immune protection against LM remain poorly understood. Here we show in pregnant women that increased serum progesterone levels are associated with DNA hypermethylation of IFN-γ gene promoter region and decreased IFN-γ production in CD8 Tm cells upon antigen-non-specific stimulation ex vivo. Moreover, IFN-γ gene hypermethylation and significantly reduced IFN-γ production post LM infection in antigen-non-specific CD8 Tm cells are also observed in pregnant mice or progesterone treated non-pregnant female mice, which is a reversible phenotype following demethylation treatment. Importantly, antigen-non-specific CD8 Tm cells from progesterone treated mice have impaired anti-LM protection when adoptive transferred in either pregnant wild type mice or IFN-γ-deficient mice, and demethylation treatment rescues the adoptive protection of such CD8 Tm cells. These data demonstrate that increased progesterone impairs immune protective functions of antigen-non-specific CD8 Tm cells via inducing IFN-γ gene hypermethylation. Our findings thus provide insights into a new mechanism through which increased female sex hormone regulate CD8 Tm cell functions during pregnancy.

Immunohistochemical study of p53 and proliferating cell nuclear antigen expression in odontogenic keratocyst and periapical cyst

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Thara Purath Sajeevan

2014-01-01

Full Text Available Introduction: p53 protein is a product of p53 gene, which is now classified as a tumor suppressor gene. The gene is a frequent target for mutation, being seen as a common step in the pathogenesis of many human cancers. Proliferating cell nuclear antigen (PCNA is an auxiliary protein of DNA polymerase delta and plays a critical role in initiation of cell proliferation. Aim: The aim of this study is to assess and compare the expression of p53 and PCNA in lining epithelium of odontogenic keratocyst (OKC and periapical cyst (PA. Materials and Methods: A total of 20 cases comprising 10 OKC and 10 PA were included in retrospective study. Three paraffin section of 4 μm were cut, one was used for routine hematoxylin and eosin stain, while the other two were used for immunohistochemistry. Statistical analysis was performed using Chi-square test. Results: The level of staining and intensity were assessed in all these cases. OKC showed PCNA expression in all cases (100%, whereas in perapical cyst only 60% of cases exhibited PCNA staining. (1 OKC showed p53 expression in 6 cases (60% whereas in PA only 10% of the cases exhibited p53 staining. Chi-square test showed PCNA staining intensity was more significant than p53 in OKC. (2 The staining intensity of PA using p53, PCNA revealed that PCNA stating intensity was more significant than p53. Conclusion: OKC shows significant proliferative activity than PA using PCNA and p53. PCNA staining was more intense when compared with p53 in both OKC and PA.

Molecular Cloning and Sequence Analysis of the Sta58 Major Antigen Gene of Rickettsia tsutsugamushi: Sequence homology and Antigenic Comparison of Sta58 to the 60-Kilodalton Family of Stress Proteins

Science.gov (United States)

1990-05-01

encoding the animals have shown that both cellular and humoral immune Sta58 protein antigen in E. coli. DNA sequence analysis of a responses occur after...infection, with the cellular immune 2.9-kilobase (kb) HindIl fragment carrying the Sta58 gene response being required for protection (16, 19, 25, 42...The first evidence of a 60-kDa common HtpB antigen) reacted strongly with protein antigens in the antigen family (Hsp6O) among procaryotes was based

A Killer Immunoglobulin - Like Receptor Gene - Content Haplotype and A Cognate Human Leukocyte Antigen Ligand are Associated with Autism

OpenAIRE

Torres, Anthony; Westover, Jonna; Benson, Michael; Johnson, Randall; Dykes, Annelise

2016-01-01

The killing activity of natural killer cells is largely regulated by the binding of class I human leukocyte antigen cognate ligands to killer cell immunoglobulin - like receptor proteins. The killer cell immunoglobulin - like receptor gene - complex contains genes that activate and others that inhibit the killing state of natural killer cells depending on the binding of specific human leukocyte antigen cognate ligands. It has been suggested in previous publications that activating human leuko...

An engineered Lactococcus lactis strain exerts significant immune responses through efficient expression and delivery of Helicobacter pylori Lpp20 antigen.

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Zhang, Rongguang; Peng, Xiaoyan; Duan, Guangcai; Shi, Qingfeng; Chen, Shuaiyin; Wang, Chen; Fan, Qingtang; Xi, Yuanlin

2016-12-01

To produce and deliver Helicobacter pylori lipoprotein Lpp20 via using Lactococcus lactis with aim of developing an efficient way to use this protective antigen in vaccine formulation. An engineered L. lactis strain carrying the lpp20 gene from H. pylori was constructed. The inducible expression of Lpp20 in L. lactis was detected as a 20 kDa intracellular protein by SDS-PAGE. Lpp20 constituted 10 % of the L. lactis cellular proteins. The expression product was highly immunoreactive, as demonstrated by western blot assays using mouse anti-H. pylori sera. Animal experimentation showed that oral vaccination with the engineered strain excited significantly elevated levels of serum Lpp20-specific IgG antibodies in BALB/c mice (P lactis, demonstrating an efficient utilization mode of Lpp20 in anti-H. pylori vaccination.

Identifying potential maternal genes of Bombyx mori using digital gene expression profiling

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Xu, Pingzhen

2018-01-01

Maternal genes present in mature oocytes play a crucial role in the early development of silkworm. Although maternal genes have been widely studied in many other species, there has been limited research in Bombyx mori. High-throughput next generation sequencing provides a practical method for gene discovery on a genome-wide level. Herein, a transcriptome study was used to identify maternal-related genes from silkworm eggs. Unfertilized eggs from five different stages of early development were used to detect the changing situation of gene expression. The expressed genes showed different patterns over time. Seventy-six maternal genes were annotated according to homology analysis with Drosophila melanogaster. More than half of the differentially expressed maternal genes fell into four expression patterns, while the expression patterns showed a downward trend over time. The functional annotation of these material genes was mainly related to transcription factor activity, growth factor activity, nucleic acid binding, RNA binding, ATP binding, and ion binding. Additionally, twenty-two gene clusters including maternal genes were identified from 18 scaffolds. Altogether, we plotted a profile for the maternal genes of Bombyx mori using a digital gene expression profiling method. This will provide the basis for maternal-specific signature research and improve the understanding of the early development of silkworm. PMID:29462160

Expression of a hantavirus N protein and its efficacy as antigen in immune assays

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L.T.M. Figueiredo

2008-07-01

Full Text Available Hantavirus cardiopulmonary syndrome (HCPS has been recognized as an important public heath problem. Five hantaviruses associated with HCPS are currently known in Brazil: Juquitiba, Araraquara, Laguna Negra-like, Castelo dos Sonhos, and Anajatuba viruses. The laboratory diagnosis of HCPS is routinely carried out by the detection of anti-hantavirus IgM and/or IgG antibodies. The present study describes the expression of the N protein of a hantavirus detected in the blood sample of an HCPS patient. The entire S segment of the virus was amplified and found to be 1858 nucleotides long, with an open reading frame of 1287 nucleotides that encodes a protein of 429 amino acids. The nucleotide sequence described here showed a high identity with the N protein gene of Araraquara virus. The entire N protein was expressed using the vector pET200D and the Escherichia coli BL21 strain. The expression of the recombinant protein was confirmed by the detection of a 52-kDa protein by Western blot using a pool of human sera obtained from HCPS patients, and by specific IgG detection in five serum samples of HCPS patients tested by ELISA. These results suggest that the recombinant N protein could be used as an antigen for the serological screening of hantavirus infection.

Time-Course Gene Set Analysis for Longitudinal Gene Expression Data.

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Boris P Hejblum

2015-06-01

Full Text Available Gene set analysis methods, which consider predefined groups of genes in the analysis of genomic data, have been successfully applied for analyzing gene expression data in cross-sectional studies. The time-course gene set analysis (TcGSA introduced here is an extension of gene set analysis to longitudinal data. The proposed method relies on random effects modeling with maximum likelihood estimates. It allows to use all available repeated measurements while dealing with unbalanced data due to missing at random (MAR measurements. TcGSA is a hypothesis driven method that identifies a priori defined gene sets with significant expression variations over time, taking into account the potential heterogeneity of expression within gene sets. When biological conditions are compared, the method indicates if the time patterns of gene sets significantly differ according to these conditions. The interest of the method is illustrated by its application to two real life datasets: an HIV therapeutic vaccine trial (DALIA-1 trial, and data from a recent study on influenza and pneumococcal vaccines. In the DALIA-1 trial TcGSA revealed a significant change in gene expression over time within 69 gene sets during vaccination, while a standard univariate individual gene analysis corrected for multiple testing as well as a standard a Gene Set Enrichment Analysis (GSEA for time series both failed to detect any significant pattern change over time. When applied to the second illustrative data set, TcGSA allowed the identification of 4 gene sets finally found to be linked with the influenza vaccine too although they were found to be associated to the pneumococcal vaccine only in previous analyses. In our simulation study TcGSA exhibits good statistical properties, and an increased power compared to other approaches for analyzing time-course expression patterns of gene sets. The method is made available for the community through an R package.

Antigen Loss Variants: Catching Hold of Escaping Foes.

Science.gov (United States)

Vyas, Maulik; Müller, Rolf; Pogge von Strandmann, Elke

2017-01-01

Since mid-1990s, the field of cancer immunotherapy has seen steady growth and selected immunotherapies are now a routine and preferred therapeutic option of certain malignancies. Both active and passive cancer immunotherapies exploit the fact that tumor cells express specific antigens on the cell surface, thereby mounting an immune response specifically against malignant cells. It is well established that cancer cells typically lose surface antigens following natural or therapy-induced selective pressure and these antigen-loss variants are often the population that causes therapy-resistant relapse. CD19 and CD20 antigen loss in acute lymphocytic leukemia and chronic lymphocytic leukemia, respectively, and lineage switching in leukemia associated with mixed lineage leukemia (MLL) gene rearrangements are well-documented evidences in this regard. Although increasing number of novel immunotherapies are being developed, majority of these do not address the control of antigen loss variants. Here, we review the occurrence of antigen loss variants in leukemia and discuss the therapeutic strategies to tackle the same. We also present an approach of dual-targeting immunoligand effectively retargeting NK cells against antigen loss variants in MLL-associated leukemia. Novel immunotherapies simultaneously targeting more than one tumor antigen certainly hold promise to completely eradicate tumor and prevent therapy-resistant relapses.

Antibodies to variant antigens on the surfaces of infected erythrocytes are associated with protection from malaria in Ghanaian children

DEFF Research Database (Denmark)

Dodoo, D; Staalsoe, T; Giha, H

2001-01-01

Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) is a variant antigen expressed on the surface of infected erythrocytes. Each parasite genome contains about 40 PfEMP1 genes, but only 1 PfEMP1 gene is expressed at a given time. PfEMP1 serves as a parasite-sequestering ligand to endoth...

Mechanisms of Surface Antigenic Variation in the Human Pathogenic Fungus Pneumocystis jirovecii.

Science.gov (United States)

Schmid-Siegert, Emanuel; Richard, Sophie; Luraschi, Amanda; Mühlethaler, Konrad; Pagni, Marco; Hauser, Philippe M

2017-11-07

Microbial pathogens commonly escape the human immune system by varying surface proteins. We investigated the mechanisms used for that purpose by Pneumocystis jirovecii This uncultivable fungus is an obligate pulmonary pathogen that in immunocompromised individuals causes pneumonia, a major life-threatening infection. Long-read PacBio sequencing was used to assemble a core of subtelomeres of a single P. jirovecii strain from a bronchoalveolar lavage fluid specimen from a single patient. A total of 113 genes encoding surface proteins were identified, including 28 pseudogenes. These genes formed a subtelomeric gene superfamily, which included five families encoding adhesive glycosylphosphatidylinositol (GPI)-anchored glycoproteins and one family encoding excreted glycoproteins. Numerical analyses suggested that diversification of the glycoproteins relies on mosaic genes created by ectopic recombination and occurs only within each family. DNA motifs suggested that all genes are expressed independently, except those of the family encoding the most abundant surface glycoproteins, which are subject to mutually exclusive expression. PCR analyses showed that exchange of the expressed gene of the latter family occurs frequently, possibly favored by the location of the genes proximal to the telomere because this allows concomitant telomere exchange. Our observations suggest that (i) the P. jirovecii cell surface is made of a complex mixture of different surface proteins, with a majority of a single isoform of the most abundant glycoprotein, (ii) genetic mosaicism within each family ensures variation of the glycoproteins, and (iii) the strategy of the fungus consists of the continuous production of new subpopulations composed of cells that are antigenically different. IMPORTANCE Pneumocystis jirovecii is a fungus causing severe pneumonia in immunocompromised individuals. It is the second most frequent life-threatening invasive fungal infection. We have studied the mechanisms

Leishmania-specific surface antigens show sub-genus sequence variation and immune recognition.

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Daniel P Depledge

2010-09-01

Full Text Available A family of hydrophilic acylated surface (HASP proteins, containing extensive and variant amino acid repeats, is expressed at the plasma membrane in infective extracellular (metacyclic and intracellular (amastigote stages of Old World Leishmania species. While HASPs are antigenic in the host and can induce protective immune responses, the biological functions of these Leishmania-specific proteins remain unresolved. Previous genome analysis has suggested that parasites of the sub-genus Leishmania (Viannia have lost HASP genes from their genomes.We have used molecular and cellular methods to analyse HASP expression in New World Leishmania mexicana complex species and show that, unlike in L. major, these proteins are expressed predominantly following differentiation into amastigotes within macrophages. Further genome analysis has revealed that the L. (Viannia species, L. (V. braziliensis, does express HASP-like proteins of low amino acid similarity but with similar biochemical characteristics, from genes present on a region of chromosome 23 that is syntenic with the HASP/SHERP locus in Old World Leishmania species and the L. (L. mexicana complex. A related gene is also present in Leptomonas seymouri and this may represent the ancestral copy of these Leishmania-genus specific sequences. The L. braziliensis HASP-like proteins (named the orthologous (o HASPs are predominantly expressed on the plasma membrane in amastigotes and are recognised by immune sera taken from 4 out of 6 leishmaniasis patients tested in an endemic region of Brazil. Analysis of the repetitive domains of the oHASPs has shown considerable genetic variation in parasite isolates taken from the same patients, suggesting that antigenic change may play a role in immune recognition of this protein family.These findings confirm that antigenic hydrophilic acylated proteins are expressed from genes in the same chromosomal region in species across the genus Leishmania. These proteins are

The rules of gene expression in plants: Organ identity and gene body methylation are key factors for regulation of gene expression in Arabidopsis thaliana

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Gutiérrez Rodrigo A

2008-09-01

Full Text Available Abstract Background Microarray technology is a widely used approach for monitoring genome-wide gene expression. For Arabidopsis, there are over 1,800 microarray hybridizations representing many different experimental conditions on Affymetrix™ ATH1 gene chips alone. This huge amount of data offers a unique opportunity to infer the principles that govern the regulation of gene expression in plants. Results We used bioinformatics methods to analyze publicly available data obtained using the ATH1 chip from Affymetrix. A total of 1887 ATH1 hybridizations were normalized and filtered to eliminate low-quality hybridizations. We classified and compared control and treatment hybridizations and determined differential gene expression. The largest differences in gene expression were observed when comparing samples obtained from different organs. On average, ten-fold more genes were differentially expressed between organs as compared to any other experimental variable. We defined "gene responsiveness" as the number of comparisons in which a gene changed its expression significantly. We defined genes with the highest and lowest responsiveness levels as hypervariable and housekeeping genes, respectively. Remarkably, housekeeping genes were best distinguished from hypervariable genes by differences in methylation status in their transcribed regions. Moreover, methylation in the transcribed region was inversely correlated (R2 = 0.8 with gene responsiveness on a genome-wide scale. We provide an example of this negative relationship using genes encoding TCA cycle enzymes, by contrasting their regulatory responsiveness to nitrate and methylation status in their transcribed regions. Conclusion Our results indicate that the Arabidopsis transcriptome is largely established during development and is comparatively stable when faced with external perturbations. We suggest a novel functional role for DNA methylation in the transcribed region as a key determinant

Gene Expression Analysis of Plum pox virus (Sharka Susceptibility/Resistance in Apricot (Prunus armeniaca L..

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Manuel Rubio

Full Text Available RNA-Seq has proven to be a very powerful tool in the analysis of the Plum pox virus (PPV, sharka disease/Prunus interaction. This technique is an important complementary tool to other means of studying genomics. In this work an analysis of gene expression of resistance/susceptibility to PPV in apricot is performed. RNA-Seq has been applied to analyse the gene expression changes induced by PPV infection in leaves from two full-sib apricot genotypes, "Rojo Pasión" and "Z506-7", resistant and susceptible to PPV, respectively. Transcriptomic analyses revealed the existence of more than 2,000 genes related to the pathogen response and resistance to PPV in apricot. These results showed that the response to infection by the virus in the susceptible genotype is associated with an induction of genes involved in pathogen resistance such as the allene oxide synthase, S-adenosylmethionine synthetase 2 and the major MLP-like protein 423. Over-expression of the Dicer protein 2a may indicate the suppression of a gene silencing mechanism of the plant by PPV HCPro and P1 PPV proteins. On the other hand, there were 164 genes involved in resistance mechanisms that have been identified in apricot, 49 of which are located in the PPVres region (scaffold 1 positions from 8,050,804 to 8,244,925, which is responsible for PPV resistance in apricot. Among these genes in apricot there are several MATH domain-containing genes, although other genes inside (Pleiotropic drug resistance 9 gene or outside (CAP, Cysteine-rich secretory proteins, Antigen 5 and Pathogenesis-related 1 protein; and LEA, Late embryogenesis abundant protein PPVres region could also be involved in the resistance.

The functional landscape of mouse gene expression

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Zhang Wen

2004-12-01

Full Text Available Abstract Background Large-scale quantitative analysis of transcriptional co-expression has been used to dissect regulatory networks and to predict the functions of new genes discovered by genome sequencing in model organisms such as yeast. Although the idea that tissue-specific expression is indicative of gene function in mammals is widely accepted, it has not been objectively tested nor compared with the related but distinct strategy of correlating gene co-expression as a means to predict gene function. Results We generated microarray expression data for nearly 40,000 known and predicted mRNAs in 55 mouse tissues, using custom-built oligonucleotide arrays. We show that quantitative transcriptional co-expression is a powerful predictor of gene function. Hundreds of functional categories, as defined by Gene Ontology 'Biological Processes', are associated with characteristic expression patterns across all tissues, including categories that bear no overt relationship to the tissue of origin. In contrast, simple tissue-specific restriction of expression is a poor predictor of which genes are in which functional categories. As an example, the highly conserved mouse gene PWP1 is widely expressed across different tissues but is co-expressed with many RNA-processing genes; we show that the uncharacterized yeast homolog of PWP1 is required for rRNA biogenesis. Conclusions We conclude that 'functional genomics' strategies based on quantitative transcriptional co-expression will be as fruitful in mammals as they have been in simpler organisms, and that transcriptional control of mammalian physiology is more modular than is generally appreciated. Our data and analyses provide a public resource for mammalian functional genomics.

Expression of Sox genes in tooth development.

Science.gov (United States)

Kawasaki, Katsushige; Kawasaki, Maiko; Watanabe, Momoko; Idrus, Erik; Nagai, Takahiro; Oommen, Shelly; Maeda, Takeyasu; Hagiwara, Nobuko; Que, Jianwen; Sharpe, Paul T; Ohazama, Atsushi