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1.
BMC Med Genet ; 18(1): 76, 2017 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-28738793

RESUMO

BACKGROUND: We evaluated the associations between single nucleotide polymorphisms and different clinical parameters related to type 2 diabetes mellitus (T2DM), obesity risk, and metabolic syndrome (MS) in a Kazakh cohort. METHODS: A total of 1336 subjects, including 408 T2DM patients and 928 control subjects, were recruited from an outpatient clinic and genotyped for 32 polymorphisms previously associated with T2DM and obesity-related phenotypes in other ethnic groups. For association studies, the chi-squared test or Fisher's exact test for binomial variables were used. Logistic regression was conducted to explore associations between the studied SNPs and the risk of developing T2DM, obesity, and MS, after adjustments for age and sex. RESULTS: After excluding four SNPs due to Hardy-Weinberg disequilibrium, significant associations in age-matched cohorts were found betweenT2DM and the following SNPs: rs9939609 (FTO), rs13266634 (SLC30A8), rs7961581 (TSPAN8/LGR5), and rs1799883 (FABP2). In addition, examination of general unmatched T2DM and control cohorts revealed significant associations between T2DM and SNPsrs1799883 (FABP2) and rs9939609 (FTO). Furthermore, polymorphisms in the FTO gene were associated with increased obesity risk, whereas polymorphisms in the FTO and FABP2 genes were also associated with the risk of developing MS in general unmatched cohorts. CONCLUSION: We confirmed associations between polymorphisms within the SLC30A8, TSPAN8/LGR5, FABP2, and FTO genes and susceptibility to T2DM in a Kazakh cohort, and revealed significant associations with anthropometric and metabolic traits. In particular, FTO and FABP2 gene polymorphisms were significantly associated with susceptibility to MS and obesity in this cohort.


Assuntos
Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Diabetes Mellitus Tipo 2/genética , Proteínas de Ligação a Ácido Graxo/genética , Síndrome Metabólica/genética , Obesidade/genética , Adolescente , Adulto , Povo Asiático , Diabetes Mellitus Tipo 2/patologia , Etnicidade , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Cazaquistão , Masculino , Síndrome Metabólica/patologia , Pessoa de Meia-Idade , Obesidade/patologia , Polimorfismo de Nucleotídeo Único , Fatores de Risco
2.
Genome Res ; 23(2): 331-40, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23038767

RESUMO

We have developed an approach termed PUB-NChIP (proximity utilizing biotinylation with native ChIP) to purify and study the protein composition of chromatin in proximity to a nuclear protein of interest. It is based on coexpression of (1) a protein of interest, fused with the bacterial biotin ligase BirA, together with (2) a histone fused to a biotin acceptor peptide (BAP), which is specifically biotinylated by BirA-fusion in the proximity of the protein of interest. Using the RAD18 protein as a model, we demonstrate that the RAD18-proximal chromatin is enriched in some H4 acetylated species. Moreover, the RAD18-proximal chromatin containing a replacement histone H2AZ has a different pattern of H4 acetylation. Finally, biotin pulse-chase experiments show that the H4 acetylation pattern starts to resemble the acetylation pattern of total H4 after the proximity of chromatin to RAD18 has been lost.


Assuntos
Imunoprecipitação da Cromatina/métodos , Cromatina/metabolismo , Proteínas Nucleares/metabolismo , Acetilação , Biotinilação/métodos , Linhagem Celular , Histonas , Humanos , Processamento de Proteína Pós-Traducional
3.
BMC Genet ; 17: 23, 2016 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-26785747

RESUMO

BACKGROUND: Studies of genes involved in the absorption, distribution, metabolism, and excretion (ADME) of drugs are crucial to the development of therapeutics in clinical medicine. Such data provide information that may improve our understanding of individual differences in sensitivity or resistance to certain drugs, thereby helping to avoid adverse drug reactions (ADRs) in patients and improve the quality of therapies. Here, we aimed to analyse single nucleotide polymorphisms (SNPs) involved in the ADME of multiple drugs in Kazakhs from Kazakhstan. RESULTS: A total of 158 SNPs involved in the ADME of various drugs were studied. We analysed 320 Kazakh DNA samples using OpenArray genotyping. Of the 158 SNPs, 75 were not found in heterozygous or homozygous variants. Comparative analysis among Kazakhs and world populations showed a fairly high percentage of population differentiation. CONCLUSION: These results provide further information for pharmacogenetic databases and may contribute to the development of personalized approaches and safer therapies for the Kazakh population. Moreover, these data provide insights into the different racial groups that may have contributed to the Kazakh population.


Assuntos
Povo Asiático/genética , Preparações Farmacêuticas/metabolismo , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Frequência do Gene , Genótipo , Haplótipos , Humanos , Cazaquistão , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Grupos Raciais/genética , Adulto Jovem
4.
Biochem Biophys Res Commun ; 430(3): 1182-7, 2013 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-23261450

RESUMO

Two blind source separation methods (Independent Component Analysis and Non-negative Matrix Factorization), developed initially for signal processing in engineering, found recently a number of applications in analysis of large-scale data in molecular biology. In this short review, we present the common idea behind these methods, describe ways of implementing and applying them and point out to the advantages compared to more traditional statistical approaches. We focus more specifically on the analysis of gene expression in cancer. The review is finalized by listing available software implementations for the methods described.


Assuntos
Biomarcadores Tumorais/genética , Perfilação da Expressão Gênica/estatística & dados numéricos , Neoplasias/genética , Análise de Componente Principal/métodos , Transformação Celular Neoplásica/genética , Humanos , Transcriptoma
5.
Croat Med J ; 54(1): 17-24, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23444242

RESUMO

AIM: To study the genetic relationship of Kazakhs from East Kazakhstan to other Eurasian populations by examining paternal and maternal DNA lineages. METHODS: Whole blood samples were collected in 2010 from 160 unrelated healthy Kazakhs residing in East Kazakhstan. Genomic DNA was extracted with Wizard genomic DNA Purification Kit. Nucleotide sequence of hypervariable segment I of mitochondrial DNA (mtDNA) was determined and analyzed. Seventeen Y-short tandem repeat (STR) loci were studied in 67 samples with the AmpFiSTR Y-filer PCR Amplification Kit. In addition, mtDNA data for 2701 individuals and Y-STR data for 677 individuals were retrieved from the literature for comparison. RESULTS: There was a high degree of genetic differentiation on the level of mitochondrial DNA. The majority of maternal lineages belonged to haplogroups common in Central Asia. In contrast, Y-STR data showed very low genetic diversity, with the relative frequency of the predominant haplotype of 0.612. CONCLUSION: The results revealed different migration patterns in the population sample, showing there had been more migration among women. mtDNA genetic diversity in this population was equivalent to that in other Central Asian populations. Genetic evidence suggests the existence of a single paternal founder lineage in the population of East Kazakhstan, which is consistent with verbal genealogical data of the local tribes.


Assuntos
Povo Asiático/genética , Cromossomos Humanos Y/genética , DNA Mitocondrial/genética , Genética Populacional , Adulto , Feminino , Pool Gênico , Variação Genética , Haplótipos , Humanos , Cazaquistão , Repetições de Microssatélites , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Adulto Jovem
6.
PLoS One ; 17(11): e0277771, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36445929

RESUMO

As a historical nomadic group in Central Asia, Kazaks have mainly inhabited the steppe zone from the Altay Mountains in the East to the Caspian Sea in the West. Fine scale characterization of the genetic profile and population structure of Kazaks would be invaluable for understanding their population history and modeling prehistoric human expansions across the Eurasian steppes. With this mind, we characterized the maternal lineages of 200 Kazaks from Jetisuu at mitochondrial genome level. Our results reveal that Jetisuu Kazaks have unique mtDNA haplotypes including those belonging to the basal branches of both West Eurasian (R0, H, HV) and East Eurasian (A, B, C, D) lineages. The great diversity observed in their maternal lineages may reflect pivotal geographic location of Kazaks in Eurasia and implies a complex history for this population. Comparative analyses of mitochondrial genomes of human populations in Central Eurasia reveal a common maternal genetic ancestry for Turko-Mongolian speakers and their expansion being responsible for the presence of East Eurasian maternal lineages in Central Eurasia. Our analyses further indicate maternal genetic affinity between the Sherpas from the Tibetan Plateau with the Turko-Mongolian speakers.


Assuntos
Genoma Mitocondrial , Humanos , Animais , Resolução de Problemas , Etnicidade , DNA Mitocondrial/genética , Gerbillinae , China
7.
J Proteome Res ; 10(10): 4416-27, 2011 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-21842862

RESUMO

The common techniques to study protein-protein proximity in vivo are not well adapted to the capabilities and the expertise of a standard proteomics laboratory, typically based on the use of mass spectrometry. With the aim of closing this gap, we have developed PUB-MS (for proximity utilizing biotinylation and mass spectrometry), an approach to monitor protein-protein proximity, based on biotinylation of a protein fused to a biotin-acceptor peptide (BAP) by a biotin-ligase, BirA, fused to its interaction partner. The biotinylation status of the BAP can be further detected by either Western analysis or mass spectrometry. The BAP sequence was redesigned for easy monitoring of the biotinylation status by LC-MS/MS. In several experimental models, we demonstrate that the biotinylation in vivo is specifically enhanced when the BAP- and BirA-fused proteins are in proximity to each other. The advantage of mass spectrometry is demonstrated by using BAPs with different sequences in a single experiment (allowing multiplex analysis) and by the use of stable isotopes. Finally, we show that our methodology can be also used to study a specific subfraction of a protein of interest that was in proximity with another protein at a predefined time before the analysis.


Assuntos
Espectrometria de Massas/métodos , Proteômica/métodos , Sequência de Aminoácidos , Biotina/química , Biotinilação , Fibroblastos/citologia , Transferência Ressonante de Energia de Fluorescência/métodos , Células HEK293 , Humanos , Isótopos/química , Dados de Sequência Molecular , Mapeamento de Interação de Proteínas/métodos , Proteínas Recombinantes/química
8.
Virus Res ; 294: 198291, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33388393

RESUMO

Yellow fever virus, the prototype in the genus Flavivirus, was used to develop viruses in which the nonstructural protein NS1 is genetically fused to GFP in the context of viruses capable of autonomous replication. The GFP-tagging of NS1 at the amino-terminus appeared possible despite the presence of a small and functionally important domain at the NS1's amino-terminus which can be distorted by such fusing. GFP-tagged NS1 viruses were rescued from DNA-launched molecular clones. The initially produced GFP-tagged NS1 virus was capable of only poor replication. Sequential passages of the virus in cell cultures resulted in the appearance of mutations in GFP, NS4A, NS4B and NS5. The mutations which change amino acid sequences of GFP, NS4A and NS5 have the adaptive effect on the replication of GFP-tagged NS1 viruses. The pattern of GFP-fluorescence indicates that the GFP-NS1 fusion protein is produced into the endoplasmic reticulum. The intracellular GFP-NS1 fusion protein colocalizes with dsRNA. The discovered forms of extracellular GFP-NS1 possibly include tetramers and hexamers.


Assuntos
Flavivirus , Vírus da Febre Amarela , Sequência de Aminoácidos , Flavivirus/genética , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo , Replicação Viral , Vírus da Febre Amarela/genética , Vírus da Febre Amarela/metabolismo
9.
Anal Chem ; 82(19): 8131-6, 2010 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-20815336

RESUMO

In this paper, we describe the development of an electrochemical DNA aptamer-based biosensor for detection of interferon (IFN)-γ. A DNA hairpin containing IFN-γ-binding aptamer was thiolated, conjugated with methylene blue (MB) redox tag, and immobilized on a gold electrode by self-assembly. Binding of IFN-γ caused the aptamer hairpin to unfold, pushing MB redox molecules away from the electrode and decreasing electron-transfer efficiency. The change in redox current was quantified using square wave voltammetry (SWV) and was found to be highly sensitive to IFN-γ concentration. The limit of detection for optimized biosensor was 0.06 nM with linear response extending to 10 nM. This aptasensor was specific to IFN-γ in the presence of overabundant serum proteins. Importantly, the same aptasensor could be regenerated by disrupting aptamer-IFN-γ complex in urea buffer and reused multiple times. Unlike standard sandwich immunoassays, the aptasensor described here allowed one to detect IFN-γ binding directly without the need for multiple washing steps and reagents. An electrochemical biosensor for simple and sensitive detection of IFN-γ demonstrated in this paper will have future applications in immunology, cancer research, and infectious disease monitoring.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Interferon gama/análise , Proteínas Sanguíneas/química , Eletrodos , Inibidores Enzimáticos/química , Ouro/química , Humanos , Azul de Metileno/química , Oxirredução , Proteínas Recombinantes , Ressonância de Plasmônio de Superfície
10.
Anal Chem ; 82(5): 1851-7, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20121141

RESUMO

Traditional antibody-based affinity sensing strategies employ multiple reagents and washing steps and are unsuitable for real-time detection of analyte binding. Aptamers, on the other hand, may be designed to monitor binding events directly, in real-time, without the need for secondary labels. The goal of the present study was to design an aptamer beacon for fluorescence resonance energy transfer (FRET)-based detection of interferon-gamma (IFN-gamma)--an important inflammatory cytokine. Variants of DNA aptamer modified with biotin moieties and spacers were immobilized on avidin-coated surfaces and characterized by surface plasmon resonance (SPR). The SPR studies showed that immobilization of aptamer via the 3' end resulted in the best binding IFN-gamma (K(d) = 3.44 nM). This optimal aptamer variant was then used to construct a beacon by hybridizing fluorophore-labeled aptamer with an antisense oligonucleotide strand carrying a quencher. SPR studies revealed that IFN-gamma binding with an aptamer beacon occurred within 15 min of analyte introduction--suggesting dynamic replacement of the quencher-complementary strand by IFN-gamma molecules. To further highlight biosensing applications, aptamer beacon molecules were immobilized inside microfluidic channels and challenged with varying concentration of analyte. Fluorescence microscopy revealed low fluorescence in the absence of analyte and high fluorescence after introduction of IFN-gamma. Importantly, unlike traditional antibody-based immunoassays, the signal was observed directly upon binding of analyte without the need for multiple washing steps. The surface immobilized aptamer beacon had a linear range from 5 to 100 nM and a lower limit of detection of 5 nM IFN-gamma. In conclusion, we designed a FRET-based aptamer beacon for monitoring of an inflammatory cytokine-IFN-gamma. In the future, this biosensing strategy will be employed to monitor dynamics of cytokine production by the immune cells.


Assuntos
Aptâmeros de Nucleotídeos , Interferon gama/análise , Sequência de Bases , DNA , Transferência Ressonante de Energia de Fluorescência , Imunoensaio/métodos , Ressonância de Plasmônio de Superfície
11.
Anal Chem ; 82(9): 3736-44, 2010 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-20359168

RESUMO

Characterization of leukocytes is an integral part of blood analysis and blood-based diagnostics. In the present paper, we combine lensless holographic imaging with antibody microarrays for rapid and multiparametric analysis of leukocytes from human blood. Monoclonal antibodies (Abs) specific for leukocyte surface antigens (CD4 and CD8) and cytokines (TNF-alpha, IFN-gamma, IL-2) were printed in an array so as to juxtapose cell capture and cytokine detection antibody (Ab) spots. Integration of Ab microarrays into a microfluidic flow chamber (4 muL volume) followed by incubation with human blood resulted in capture of CD4 and CD8 T-cells on specific Ab spots. On-chip mitogenic activation of these cells induced release of cytokine molecules that were subsequently captured on neighboring anticytokine Ab spots. The binding of IL-2, TNF-alpha, and IFN-gamma molecules on their respective Ab spots was detected using horseradish peroxidase (HRP)-labeled anticytokine Abs and a visible color reagent. Lensfree holographic imaging was then used to rapidly ( approximately 4 s) enumerate CD4 and CD8 T-lymphocytes captured on Ab spots and to quantify the cytokine signal emanating from IL-2, TNF-alpha, and IFN-gamma spots on the same chip. To demonstrate the utility of our approach for infectious disease monitoring, blood samples of healthy volunteers and human immunodeficiency virus (HIV)-infected patients were analyzed to determine the CD4/CD8 ratio, an important HIV/AIDS diagnostic marker. The ratio obtained by lensfree on-chip imaging of CD4 and CD8 T-cells captured on Ab spots was in close agreement with conventional microscopy-based cell counting. The present paper, describing tandem use of Ab microarrays and lensfree holographic imaging, paves the way for future development of miniature cytometry devices for multiparametric blood analysis at the point of care or in a resource-limited setting.


Assuntos
Anticorpos , Holografia , Contagem de Leucócitos , Análise em Microsséries , Humanos , Análise em Microsséries/economia , Análise em Microsséries/instrumentação , Análise em Microsséries/métodos
12.
Anal Chem ; 81(19): 8150-6, 2009 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-19739655

RESUMO

The cytokine production by leukocytes correlates with body's ability to mount an immune response and therefore has high diagnostic value. In the present study we employed microfabricated surfaces to capture T-cells from minimally processed human blood, arrange these cells into a single cell array, and then detect interferon (IFN)-gamma released from individual cells. The fabrication of cell capture surfaces started with coating a silane-modified glass slide with a uniform layer of poly(ethylene glycol) (PEG) hydrogel. The hydrogel-coated slide was lyophilized and then incubated with a mixture of monoclonal anti-IFN-gamma and anti-CD4 antibodies (Abs). To define sites for single cell attachment, PEG hydrogel microwells (20 microm diameter) were photolithographically patterned on top of the Ab-containing hydrogel layer. This micropatterning process resulted in fabrication of PEG hydrogel microwells with Ab-decorated bottom and nonfouling walls. To minimize the blood volume requirement and to precisely define shear stress conditions, the engineered surface was enclosed inside a PDMS-based microfluidic device. Introduction of red blood cell (RBC) depleted whole human blood followed by controlled washing led to the isolation of individual CD4 T-cells within PEG microwells. Mitogenic activation and immunofluorescent staining performed inside the microfluidic chamber revealed IFN-gamma cytokine signal colocalized with specific T-cells. The device and process presented here will be expanded in the future to enable multiparametric functional analysis of immune cells organized into high density single cell arrays.


Assuntos
Interferon gama/metabolismo , Técnicas Analíticas Microfluídicas/métodos , Linfócitos T/imunologia , Anticorpos Imobilizados/imunologia , Anticorpos Imobilizados/metabolismo , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/metabolismo , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Polietilenoglicóis/química , Linfócitos T/metabolismo
13.
Biochem Biophys Res Commun ; 380(3): 575-80, 2009 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-19285003

RESUMO

Gut-associated lymphoid tissue is a major target and reservoir of human immunodeficiency virus (HIV)-infected T-cells. Our studies seek to recapitulate, in vitro, interactions between HIV-infected T-lymphocytes and intestinal epithelial cells in order to investigate the mechanisms underlying the disruption of normal epithelial cell and barrier function. Here, we describe a novel approach for creating co-cultures of healthy or HIV-infected T-lymphocytes (Jurkat) and human intestinal epithelial (HT-29) cells where both cell types are positioned on the same surface in a price spatial configuration (micropattern). This co-culture method simplified observation/monitoring of the two cell types and was particularly suited for laser microdissection-based retrieval of the desired cells for downstream gene expressions studies. DNA microarray analysis of epithelial cells retrieved from co-cultures with HIV-1-infected vs. uninfected Jurkat cells revealed that epithelial cells from HIV-infected co-cultures exhibited gene expression patterns consistent with disruption of epithelial barrier formation. Overall, the micropatterned co-culture system described here is envisioned as a valuable new tool for delineating how HIV and other infections contribute to dysfunction of mucosal epithelium.


Assuntos
Infecções por HIV/imunologia , HIV-1 , Mucosa Intestinal/imunologia , Linfócitos T/imunologia , Linfócitos T/virologia , Técnicas de Cocultura , Células Epiteliais/imunologia , Infecções por HIV/genética , Humanos , Imunidade nas Mucosas , Células Jurkat , Modelos Biológicos , Análise de Sequência com Séries de Oligonucleotídeos
14.
J Virol Methods ; 274: 113734, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31525396

RESUMO

Plasmacytoma (myeloma) cells have a large protein expression capacity, although their industrial use is confined to stable expression systems. Vectors derived from genomes of viruses from the genus Alphavirus allow obtaining of high yields of target proteins but their use is limited to transient expression. Little information has been published to date on attempts to combine the myeloma cells as hosts with alphaviruses as expression vectors. A plasmid construct which allows rescue of a model alphavirus Venezuelan equine encephalitis virus (VEE) upon transfection of a cell culture was created. Mutations in the capsid and nsP2 genes allow for less cytopathogenic propagation of the virus. A cDNA-copy of the genome was placed in a plasmid under the control of the CMV promoter for virus rescue following DNA transfection. Parameters for the virus rescue by electroporating of the infectious clone in murine myeloma cells (NS0) were optimized. The highest FFU counts (1.2 × 105 FFU per 10 ug DNA) were produced with 2 pulses (voltage 250 V, capacitance 960 u F) and the best electroporation buffer was selected from eight buffers. Self-sustained VEE infection was established in NS0 cultures with high titers (8 × 108 FFU/ml) of the virus, despite a fraction of infected cells dying during 5-days observation. Further development of the NS0-VEE expression system may require addressing of apoptosis induced by VEE.


Assuntos
Biotecnologia/métodos , Linhagem Celular Tumoral , Vírus da Encefalite Equina Venezuelana/crescimento & desenvolvimento , Expressão Gênica , Vetores Genéticos , Proteínas Recombinantes/biossíntese , Animais , Efeito Citopatogênico Viral , DNA Complementar/genética , Eletroporação , Vírus da Encefalite Equina Venezuelana/genética , Camundongos , Plasmídeos , Regiões Promotoras Genéticas , Proteínas Recombinantes/genética , Transfecção , Cultura de Vírus/métodos
15.
Lab Chip ; 8(12): 2197-205, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19023487

RESUMO

Cytokines are produced by immune cells in response to viral or bacterial pathogens and therefore have significant diagnostic value. The goal of the present study was to develop a miniature device for detection of interleukin (IL)-2 and interferon (IFN)-gamma cytokines secreted by a small population of CD4 and CD8 T-cells. Microarrays of T-cell- and cytokine-specific Ab spots were printed onto poly(ethylene glycol) (PEG) hydrogel-coated glass slides and enclosed inside a microfluidic device, creating a miniature ( approximately 3 microL) immunoreaction chamber. Introduction of the red blood cell (RBC) depleted whole human blood into the microfluidic device followed by washing at a pre-defined shear stress resulted in isolation of pure CD4 and CD8 T-cells on their respective Ab spots. Importantly, the cells became localized next to anti-IL-2 and -IFN-gamma Ab spots. Mitogenic activation of the captured T-cells was followed by immunofluorescent staining (all steps carried out inside a microfluidic device), revealing concentration gradients of surface-bound cytokine molecules. A microarray scanner was then used to quantify the concentration of IFN-gamma and IL-2 near CD4 and CD8 T-cells. This study represents one of the first demonstrations of a microdevice for capturing desired T-cell subsets from a small blood volume and determining, on-chip, cytokine profiles of the isolated cells. Such a microdevice is envisioned as an immunology tool for multi-parametric analysis of T-cell function with direct applications in diagnosis/monitoring of HIV and other infectious diseases.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Interferon gama/análise , Interleucina-2/análise , Microfluídica/instrumentação , Microfluídica/métodos , Citometria de Fluxo , Humanos , Interferon gama/química , Interleucina-2/química , Miniaturização
16.
Anal Chem ; 80(16): 6351-7, 2008 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-18642875

RESUMO

The microarray format is being used extensively for combinatorial screening of cellular interactions with proteins, small molecules, or biomaterials. The utility of microarray-based cell cultivation approaches may be enhanced further by incorporating biosensing elements alongside the cell-adhesive ligands to enable local detection of secreted cellular products. The concept of combining cells and sensing elements in the same microarray is demonstrated in the present paper with hepatocytes serving as a model cellular system. Robotic microarraying was employed to print arrays of 300-mum-diameter collagen (I) spots alongside the antibody (Ab) spots specific to liver proteins: albumin and alpha1-antitrypsin (alpha1-AT). Protein microarrays were printed onto poly(ethylene glycol) hydrogel-coated glass slides, thus eliminating nonspecific adsorption of cells or proteins. When incubated with printed microarrays, hepatocytes became localized on collagen (I) domains but did not attach on Ab spots or elsewhere on hydrogel-coated glass substrates. Liver-specific proteins secreted by hepatocytes were captured on Ab domains in the immediate vicinity of the cells, detected with a sandwich immunofluorescent assay and quantified using a microarray scanner. Importantly, hepatic albumin and alpha1-AT production detected in the microarray was comparable to enzyme-linked immunosorbent assay measurements of these proteins. In the future, the juxtaposition of sensing Ab regions with cell arrays will be particularly useful for the detection of local appearance or loss of phenotype of cells interacting with the printed components of the cellular microenvironment.


Assuntos
Carcinoma Hepatocelular/metabolismo , Hepatócitos/metabolismo , Polietilenoglicóis/química , Análise Serial de Proteínas/métodos , Albuminas/imunologia , Albuminas/metabolismo , Animais , Carcinoma Hepatocelular/imunologia , Células Cultivadas , Colágeno Tipo I/imunologia , Colágeno Tipo I/metabolismo , Ensaio de Imunoadsorção Enzimática , Vidro/química , Hepatócitos/citologia , Humanos , Hidrogéis/química , Imunoglobulina G/imunologia , Imunoglobulina G/metabolismo , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/metabolismo , Ratos , alfa 1-Antitripsina/imunologia , alfa 1-Antitripsina/metabolismo
17.
Biochem Biophys Res Commun ; 376(1): 169-73, 2008 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-18765226

RESUMO

RNA interference (RNAi) has emerged as a powerful technology to silence arbitrary genes by designing small RNA constructs based on the targeted messenger RNA sequences. We recently developed a small molecule-controlled RNAi gene switch that combined the molecular recognition by in vitro selected RNA aptamers with versatile gene silencing by small interfering RNAs, and demonstrated for the first time, posttranscriptional modulation of RNAi through direct RNA-small molecule interaction. In this report, we describe the first application of this technology to regulate an endogenous gene in mammalian cells. As a proof-of-concept demonstration we chose to modulate expression of albumin-serum protein produced by the liver. We designed and constructed a theophylline aptamer-fused short hairpin RNA (shRNA) expression vector targeting albumin mRNA in hepatic (HepG2) cells. Transfection of HepG2 cells with the aptamer-shRNA expression vector allowed to control albumin gene expression by adding theophylline into the culture media in dose dependent fashion.


Assuntos
Aptâmeros de Nucleotídeos/genética , Expressão Gênica , Interferência de RNA , RNA Interferente Pequeno/genética , Aptâmeros de Nucleotídeos/química , Linhagem Celular , Vetores Genéticos , Humanos , Fígado/metabolismo , Interferência de RNA/efeitos dos fármacos , RNA Interferente Pequeno/química , Albumina Sérica/antagonistas & inibidores , Albumina Sérica/genética , Teofilina/farmacologia , Transfecção
18.
Clin Interv Aging ; 13: 377-388, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29551892

RESUMO

BACKGROUND: Ethnic differences exist in the frequencies of genetic variations that contribute to the risk of common disease. This study aimed to analyse the distribution of several genes, previously associated with susceptibility to type 2 diabetes and obesity-related phenotypes, in a Kazakh population. METHODS: A total of 966 individuals belonging to the Kazakh ethnicity were recruited from an outpatient clinic. We genotyped 41 common single nucleotide polymorphisms (SNPs) previously associated with type 2 diabetes in other ethnic groups and 31 of these were in Hardy-Weinberg equilibrium. The obtained allele frequencies were further compared to publicly available data from other ethnic populations. Allele frequencies for other (compared) populations were pooled from the haplotype map (HapMap) database. Principal component analysis (PCA), cluster analysis, and multidimensional scaling (MDS) were used for the analysis of genetic relationship between the populations. RESULTS: Comparative analysis of allele frequencies of the studied SNPs showed significant differentiation among the studied populations. The Kazakh population was grouped with Asian populations according to the cluster analysis and with the Caucasian populations according to PCA. According to MDS, results of the current study show that the Kazakh population holds an intermediate position between Caucasian and Asian populations. CONCLUSION: A high percentage of population differentiation was observed between Kazakh and world populations. The Kazakh population was clustered with Caucasian populations, and this result may indicate a significant Caucasian component in the Kazakh gene pool.


Assuntos
Diabetes Mellitus Tipo 2/genética , Etnicidade/genética , Marcadores Genéticos/genética , Genética Populacional , Adulto , Feminino , Frequência do Gene/genética , Predisposição Genética para Doença/genética , Genótipo , Projeto HapMap , Haplótipos/genética , Humanos , Cazaquistão , Masculino , Pessoa de Meia-Idade , Obesidade/genética , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Análise de Componente Principal
19.
Methods Mol Biol ; 1620: 33-64, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28540698

RESUMO

This chapter introduces the FastPCR software as an integrated tool environment for PCR primer and probe design, which predicts properties of oligonucleotides based on experimental studies of the PCR efficiency. The software provides comprehensive facilities for designing primers for most PCR applications and their combinations. These include the standard PCR as well as the multiplex, long-distance, inverse, real-time, group-specific, unique, overlap extension PCR for multi-fragments assembling cloning and loop-mediated isothermal amplification (LAMP). It also contains a built-in program to design oligonucleotide sets both for long sequence assembly by ligase chain reaction and for design of amplicons that tile across a region(s) of interest. The software calculates the melting temperature for the standard and degenerate oligonucleotides including locked nucleic acid (LNA) and other modifications. It also provides analyses for a set of primers with the prediction of oligonucleotide properties, dimer and G/C-quadruplex detection, linguistic complexity as well as a primer dilution and resuspension calculator. The program consists of various bioinformatical tools for analysis of sequences with the GC or AT skew, CG% and GA% content, and the purine-pyrimidine skew. It also analyzes the linguistic sequence complexity and performs generation of random DNA sequence as well as restriction endonucleases analysis. The program allows to find or create restriction enzyme recognition sites for coding sequences and supports the clustering of sequences. It performs efficient and complete detection of various repeat types with visual display. The FastPCR software allows the sequence file batch processing that is essential for automation. The program is available for download at http://primerdigital.com/fastpcr.html , and its online version is located at http://primerdigital.com/tools/pcr.html .


Assuntos
Técnicas de Amplificação de Ácido Nucleico/métodos , Oligonucleotídeos/genética , Reação em Cadeia da Polimerase/métodos , Software , Primers do DNA/genética , Internet
20.
PLoS One ; 12(12): e0189308, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29216299

RESUMO

B18R protein of Vaccinia virus binds to type I interferons and inhibits activation of interferon-mediated signal transduction. Cells which have unimpaired interferon signaling such as primary cell cultures or some industrially important cell lines are capable of development of an antiviral state. An establishment of the antiviral state limits replication of RNA-viruses and can suppress replication of RNA vectors. The interferon inhibitor B18R effectively prevents the establishment of the antiviral state. For this reason, B18R has become a ubiquitous component of protocols for epigenetic reprogramming which use transfections of RNA replicons or mRNA. Despite wide practical applicability, commercially available B18R is predominantly produced in cell cultures and little information has been published on a production and use of bacterially expressed B18R. Objectives of this study were to produce B18R in an E.coli expression system and to confirm the product's biological activity by using it to maintain RNA-vectors in cell cultures capable of the antiviral state. The described method allows the expression and efficient refolding to obtain 10-100 mg of B18R from a small-scale culture and the production process is economically attractive compared to a use of an eukaryotic expression. To check for a presence of the biological activity of bacterially-expressed B18R the protein was used to support persistence of an autonomously replicating RNA-vector in a cell culture which is capable of the antiviral state. A RNA-containing virus, Venezuelan equine encephalitis virus (VEE) can serve as an efficient vector for heterologous expression in cell cultures, although its replication is sensitive to the effects of type I interferons which limit a range of cell lines for a use with this vector. The VEE replicon was utilized to direct an expression of recombinant human granulocyte colony stimulating factor (G-CSF). The producing replicon could persist in HEK293 cells for sufficiently long time only in presence of B18R, whereas addition of B18R not only allowed persistence of the replicon but also increased production from the replicon. A model product granulocyte colony stimulating factor accumulated to 35.5 µg/ml during a 7 day experiment. This work describes efficacious expression and refolding of the viral cytokine inhibitor and demonstrates a utility of bacterially-expressed B18R.


Assuntos
Vetores Genéticos , RNA Viral/genética , Vaccinia virus/genética , Proteínas Virais/genética , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Células HEK293 , Humanos , Dobramento de Proteína , Proteínas Recombinantes/genética , Proteínas Virais/química
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