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1.
Eur J Vasc Endovasc Surg ; 46(2): 242-8, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23751217

ABSTRACT

OBJECTIVE: Based upon the well known protective effect of intracellular cyclic guanosine monophosphate (cGMP) accumulation, we tested the hypothesis that storage solution enriched with optimal concentration of the phosphodiestherase-5 inhibitor vardenafil could provide better protection of vascular grafts against reperfusion injury after long-term cold ischaemic storage. METHODS: Isolated thoracic aorta obtained from rats underwent 24-h cold ischaemic preservation in physiological saline or vardenafil (10(-11) M)-supplemented saline solution. Reperfusion injury was simulated by hypochlorite (200 µM) exposure for 30 minutes. Endothelium-dependent vasorelaxation was assessed, and histopathological and molecular-biological examination of the aortic tissue were performed. RESULTS: Compared with the control group, the saline group showed significantly attenuated endothelium-dependent maximal relaxation (Rmax) to acetylcholine after hypoxia-reoxygenation, which was significantly improved by vardenafil supplementation (Rmax control: 98 ± 1%; saline: 48 ± 6%; vardenafil: 75 ± 4%; p < .05). Vardenafil treatment significantly reduced DNA strand breaks (control: 10.6 ± 6.2%; saline: 72.5 ± 4.0%; vardenafil: 14.2 ± 5.2%; p < .05) and increased cGMP score in the aortic wall (control: 8.2 ± 0.6; saline: 4.5 ± 0.3; vardenafil: 6.7 ± 0.6; p < .05). CONCLUSIONS: Our results support the view that impairment of intracellular cGMP signalling plays a role in the pathogenesis of the endothelial dysfunction induced by cold storage warm reperfusion, which can be effectively reversed by pharmacological phosphodiesterase-5 inhibition.


Subject(s)
Aorta, Thoracic/drug effects , Endothelium, Vascular/drug effects , Imidazoles/pharmacology , Organ Preservation Solutions/pharmacology , Organ Preservation/methods , Phosphodiesterase 5 Inhibitors/pharmacology , Piperazines/pharmacology , Reperfusion Injury/prevention & control , Vascular Grafting , Vascular System Injuries/prevention & control , Animals , Aorta, Thoracic/metabolism , Aorta, Thoracic/pathology , Aorta, Thoracic/physiopathology , Aorta, Thoracic/transplantation , Apoptosis/drug effects , Cold Ischemia , Cyclic GMP/metabolism , Cytoprotection , DNA Damage , Dose-Response Relationship, Drug , Endothelium, Vascular/metabolism , Endothelium, Vascular/pathology , Endothelium, Vascular/physiopathology , Endothelium, Vascular/transplantation , Gene Expression Regulation/drug effects , Male , Rats , Rats, Sprague-Dawley , Reperfusion Injury/etiology , Reperfusion Injury/metabolism , Reperfusion Injury/pathology , Reperfusion Injury/physiopathology , Sulfones/pharmacology , Time Factors , Triazines/pharmacology , Vardenafil Dihydrochloride , Vascular Grafting/adverse effects , Vascular System Injuries/etiology , Vascular System Injuries/metabolism , Vascular System Injuries/pathology , Vascular System Injuries/physiopathology , Vasoconstriction/drug effects , Vasoconstrictor Agents/pharmacology , Vasodilation/drug effects , Vasodilator Agents/pharmacology
2.
J Pediatr Gastroenterol Nutr ; 55(4): 436-9, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22411269

ABSTRACT

Assessment of fecal calprotectin, a surrogate marker of mucosal inflammation, is a promising means to monitor therapeutic response in pediatric inflammatory bowel disease, especially if the result is readily available. We tested the performance of a novel calprotectin rapid test, Quantum Blue, versus the conventional enzyme-linked immunosorbent assay in 134 stool samples from 56 pediatric patients with Crohn disease. The intraclass correlation coefficient analysis reflected good agreement (intraclass correlation coefficient 0.97 [95% confidence interval 0.95-0.98]) but agreement was better in lower values, where dilutions were not required. Using a cutoff of 100 µg/g for normal values, the percentage agreement between the 2 tests was 87%. The optimal cutoff values to guide clinical decisions in the therapy of inflammatory bowel disease have yet to be determined.


Subject(s)
Crohn Disease/metabolism , Feces/chemistry , Inflammation/metabolism , Leukocyte L1 Antigen Complex/analysis , Adolescent , Biomarkers/analysis , Child , Child, Preschool , Confidence Intervals , Enzyme-Linked Immunosorbent Assay , Female , Humans , Infant , Leukocyte L1 Antigen Complex/metabolism , Male , Mucous Membrane/metabolism , Reference Values , Reproducibility of Results
3.
Gene Ther ; 18(2): 135-44, 2011 Feb.
Article in English | MEDLINE | ID: mdl-20668485

ABSTRACT

Encapsidation of cellular- or plasmid-derived DNA sequences during recombinant adeno-associated virus (rAAV) production has been well documented. However, most of the published data were generated from rAAV vectors manufactured by the plasmid transient transfection method. We previously reported a novel, scalable method for rAAV manufacturing based on a recombinant herpes simplex virus (rHSV) complementation system. In this report, we evaluated clearance of DNA impurities during rAAV purification, by determining the quantity of residual herpes simplex virus and cellular DNA at each process step. A single Benzonase treatment during the upstream process effectively reduced unprotected HSV and cellular DNA to <300 bp fragments, and subsequent chromatography steps completely removed these small DNA fragments. Further analysis showed that trace amounts of residual, DNase-resistant HSV and cellular DNA were present at static concentrations during subsequent purification steps, and the residual HSV DNA sequences were single stranded, ranging from 0.8 to 4.2 kb. After transduction of human embryonic kidney 293 cells with purified rAAV, the residual HSV DNA fragments were neither transcribed nor translated into HSV proteins. In summary, this manufacturing process for rAAV production was effective in removing DNA and protein contaminants and achieving a highly purified product, suitable for human clinical application.


Subject(s)
DNA, Viral/analysis , Dependovirus/genetics , Genetic Vectors , Recombination, Genetic , Simplexvirus/genetics , Animals , Cell Line , Cricetinae , Dependovirus/isolation & purification , Endodeoxyribonucleases/pharmacology , Endoribonucleases/pharmacology , Gene Transfer Techniques , HEK293 Cells , Humans , Transduction, Genetic
4.
Proc Inst Mech Eng H ; 225(3): 255-67, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21485327

ABSTRACT

The current paper presents a computer model of early diastolic (E-wave) left ventricular filling through the mitral valve. It is believed that this lumped-parameter model will be clinically useful, for example in the diagnosis of diastolic dysfunction. The model is based on the solution of the ordinary differential equations describing flow through the mitral valve, as well as equations that model the intrinsic and extrinsic behaviour of a mitral valve with variable orifice area (mimicking the opening and closing of the valve leaflets). The model was developed and calibrated using porcine data. The model has now been further validated in 12 canine trials. Values are reported of canine atrial and ventricular stiffness, active relaxation characteristics, valve natural frequency, damping coefficient, and effective orifice area measured by solving the inverse problem to obtain a best-fit match between canine empirical and simulated waveforms. The best fit was determined by minimizing the error between the simulated and empirical pressure and velocity waveforms using a minimized sum-of-squares figure of merit. The paper also presents human data addressing the feasibility of using the model in man, with Doppler velocity waveforms as the primary input to the model. The paper reports parameters measured in human patients by solving the inverse problem.


Subject(s)
Diastole/physiology , Mitral Valve/physiology , Models, Cardiovascular , Algorithms , Animals , Computer Simulation , Dogs , Electrocardiography , Feasibility Studies , Humans , Least-Squares Analysis , Swine , Ventricular Dysfunction, Left/diagnosis
5.
Thorac Cardiovasc Surg ; 58(2): 86-92, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20333570

ABSTRACT

BACKGROUND: We tested the hypothesis that pharmacological preconditioning with a newly developed, potent non-adenosine analogue A1AdoR agonist (BR-4935) improves biventricular cardiac and endothelial function after cardiopulmonary bypass. METHODS: Twelve anesthetized dogs underwent cardiopulmonary bypass. Dogs were divided into two groups: group 1 (n = 6) received saline vehicle, group 2 (n = 6) received BR-4935 before cardiopulmonary bypass. Biventricular hemodynamic variables were measured using a combined pressure-volume conductance catheter. Coronary blood flow, ATP content, malondialdehyde and myeloperoxidase levels and vasodilatative responses to acetylcholine and sodium nitroprusside were also determined. RESULTS: Administration of the A1AdoR agonist led to a significantly better recovery of left and right ventricular systolic function after 60 minutes of reperfusion. Although the vasodilatative response to sodium nitroprusside was similar in both groups, acetylcholine resulted in a significantly greater increase in coronary blood flow in the BR-4935 group. In addition, the ATP content was significantly higher in the same group. Furthermore, malondialdehyde and myeloperoxidase levels significantly decreased in the A1AdoR group. CONCLUSION: Pharmacological preconditioning with a new, potent non-adenosine analogue A1AdoR agonist improves biventricular function recovery and endothelial function after hypothermic cardiac arrest.


Subject(s)
Adenosine A1 Receptor Agonists , Aminopyrine/analogs & derivatives , Cardiopulmonary Bypass/adverse effects , Cardiotonic Agents/pharmacology , Coronary Circulation/drug effects , Coronary Vessels/drug effects , Endothelium, Vascular/drug effects , Myocardial Reperfusion Injury/prevention & control , Ventricular Function, Left/drug effects , Ventricular Function, Right/drug effects , Acetylcholine/pharmacology , Adenosine Triphosphate/metabolism , Aminopyrine/pharmacology , Animals , Coronary Vessels/physiopathology , Disease Models, Animal , Dogs , Endothelium, Vascular/physiopathology , Malondialdehyde/metabolism , Myocardial Contraction/drug effects , Myocardial Reperfusion Injury/etiology , Myocardial Reperfusion Injury/metabolism , Myocardial Reperfusion Injury/physiopathology , Nitroprusside/pharmacology , Peroxidase/metabolism , Recovery of Function , Vasodilation/drug effects , Vasodilator Agents/pharmacology
6.
Gene Ther ; 16(2): 229-39, 2009 Feb.
Article in English | MEDLINE | ID: mdl-18923452

ABSTRACT

Recombinant herpes simplex virus type 1 (rHSV)-assisted recombinant adeno-associated virus (rAAV) vector production provides a highly efficient and scalable method for manufacture of clinical grade rAAV vectors. Here, we present an rHSV co-infection system for rAAV production, which uses two ICP27-deficient rHSV constructs, one bearing the rep2 and cap (1, 2 or 9) genes of rAAV, and the second bearing an AAV2 ITR-gene of interest (GOI) cassette. The optimum rAAV production parameters were defined by producing rAAV2/GFP in HEK293 cells, yielding greater than 9000 infectious particles per cell with a 14:1 DNase resistance particle to infectious particle (DRP/ip) ratio. The optimized co-infection parameters were then used to generate large-scale stocks of rAAV1/AAT, which encode the human alpha-1-antitrypsin (hAAT) protein, and purified by column chromatography. The purified vector was extensively characterized by rAAV- and rHSV-specific assays and compared to transfection-made vector for in vivo efficacy in mice through intramuscular injection. The co-infection method was also used to produce rAAV9/AAT for comparison to rAAV1/AAT in vivo. Intramuscular administration of 1 x 10(11) DRP per animal of rHSV-produced rAAV1/AAT and rAAV9/AAT resulted in hAAT protein expression of 5.4 x 10(4) and 9.4 x 10(5) ng ml(-1) serum respectively, the latter being clinically relevant.


Subject(s)
Dependovirus/genetics , Genetic Vectors/biosynthesis , Herpesvirus 1, Human/genetics , Animals , Blotting, Western , Cell Line , Gene Transfer Techniques , Genetic Vectors/isolation & purification , Humans , Male , Mice , Mice, Inbred C57BL , Recombination, Genetic , Transfection , Virus Cultivation/methods , alpha 1-Antitrypsin/biosynthesis
7.
Science ; 237(4813): 415-7, 1987 Jul 24.
Article in English | MEDLINE | ID: mdl-3603027

ABSTRACT

The ornithine transcarbamylase-deficient sparse fur mouse is an excellent model to study the most common human urea cycle disorder. The mutation has been well characterized by both biochemical and enzymological methods, but its exact nature has not been revealed. A single base substitution in the complementary DNA for ornithine transcarbamylase from the sparse fur mouse has been identified by means of a combination of two recently described techniques for rapid mutational analysis. This strategy is simpler than conventional complementary DNA library construction, screening, and sequencing, which has often been used to find a new mutation. The ornithine transcarbamylase gene in the sparse fur mouse contains a C to A transversion that alters a histidine residue to an asparagine residue at amino acid 117.


Subject(s)
Genes , Mutation , Ornithine Decarboxylase/genetics , Amino Acid Sequence , Animals , Base Sequence , DNA/analysis , Disease Models, Animal , Mice , Mice, Mutant Strains , Ornithine Decarboxylase/deficiency , RNA, Messenger/genetics
8.
Clin Exp Immunol ; 151(1): 34-41, 2008 Jan.
Article in English | MEDLINE | ID: mdl-17991289

ABSTRACT

Inflammatory bowel disease (IBD) may result from exaggerated stimulation of the mucosal immune system by luminal bacterial flora. Bacterial products are recognized by pattern recognition receptors such as Toll-like receptors (TLRs), which are key regulators of the innate immune system. Therefore, the expression of TLR2, TLR3 and TLR4 in colonic biopsy samples taken from children with active IBD were studied and compared to controls. Colonic biopsy samples were collected from macroscopically inflamed and non-inflamed regions of the mucosa of 12 children with freshly diagnosed IBD (fdIBD) and 23 children with relapsed IBD (rIBD). Specimens were also obtained from eight controls. TLR2, TLR3 and TLR4 mRNA expression and protein levels were determined by real-time reverse transcription polymerase chain reaction (RT-PCR) and Western blot. We found higher TLR2 and TLR4 mRNA and protein levels in the inflamed colonic mucosa of children with fdIBD and rIBD compared to controls. In the non-inflamed colonic mucosa of children with fdIBD and rIBD, TLR2 and TLR4 mRNA and protein levels were similar to controls. TLR2 and TLR4 mRNA and protein levels also did not differ between children with fdIBD or rIBD in either inflamed or non-inflamed colonic mucosa. TLR3 mRNA expression and protein levels were similar in all groups studied. Our results of increased levels of TLR2 and TLR4 in the inflamed colonic mucosa of children with IBD confirm the hypothesis that innate immunity has an important role in the pathogenesis of this disease.


Subject(s)
Colon , Inflammatory Bowel Diseases/metabolism , Intestinal Mucosa/metabolism , Toll-Like Receptor 2/metabolism , Toll-Like Receptor 4/metabolism , Adolescent , Blotting, Western/methods , Case-Control Studies , Child , Disease Susceptibility , Female , Humans , Immunity, Innate , Inflammatory Bowel Diseases/immunology , Intestinal Mucosa/immunology , Male , RNA, Messenger/analysis , Recurrence , Reverse Transcriptase Polymerase Chain Reaction , Statistics, Nonparametric , Toll-Like Receptor 2/analysis , Toll-Like Receptor 2/genetics , Toll-Like Receptor 3/analysis , Toll-Like Receptor 3/genetics , Toll-Like Receptor 3/metabolism , Toll-Like Receptor 4/analysis , Toll-Like Receptor 4/genetics
9.
J Pediatr Gastroenterol Nutr ; 47(3): 283-7, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18728522

ABSTRACT

OBJECTIVES: Besides the central role of the adaptive immune system, a disturbance of innate immunity is also involved in the pathogenesis of celiac disease (CD). Inasmuch as CD and type 1 diabetes mellitus (T1DM) frequently coexist because of a common genetic predisposition, our aim was to study the frequency of CD14 C-260T and TLR4 A+896G single nucleotide polymorphisms (SNPs) and the distribution of HLA-DQ genotypes in children affected by CD, T1DM, or both. PATIENTS AND METHODS: TLR4 and CD14 SNPs were tested by polymerase chain reaction, followed by restriction fragment length polymorphism analysis in 80 children with T1DM, 100 children with CD, and 47 children with both CD and T1DM. Determination of HLA-DQ alleles was done by sequence-specific polymerase chain reaction. Frequencies were compared with those of healthy control children. RESULTS: The prevalence of the homozygous CD14 C-260TT genotype was significantly (P = 0.0081) lower in children with T1DM but not in those with CD and T1DM, compared with control children. No difference was found in the genotype and allele frequencies of TLR4 between the studied groups. In patients with T1DM, the frequency of the homozygous HLA-DQ8 genotype was significantly higher than in CD, whereas the frequency of homozygous or heterozygous HLA-DQ2 genotypes did not differ from that in control children. In patients with CD, both homozygous and heterozygous HLA-DQ2 genotypes were significantly more frequent than in the control and T1DM groups, and no elevation in the frequency of the HLA-DQ8 genotypes was observed. In patients with T1DM and those with CD and T1DM, the occurrence of HLA-DQ2/8 heterozygosity was significantly higher than in children with CD only and in control children. CONCLUSIONS: Our results suggest that in patients with T1DM, the CD14 C-260TT homozygous genotype increases the risk for the development of CD. The distribution of HLA-DQ genotype is different in children with CD and T1DM than in children with CD or T1DM only. Determination of the HLA-DQ genotype in children with T1DM may help in estimating the risk for the development of CD.


Subject(s)
Celiac Disease/genetics , Diabetes Mellitus, Type 1/genetics , HLA-DQ Antigens/genetics , Lipopolysaccharide Receptors/genetics , Toll-Like Receptor 4/genetics , Adolescent , Celiac Disease/epidemiology , Celiac Disease/immunology , Child , Child, Preschool , Comorbidity , Diabetes Mellitus, Type 1/epidemiology , Diabetes Mellitus, Type 1/immunology , Female , Gene Frequency , Genetic Predisposition to Disease , Genotype , Humans , Male , Polymerase Chain Reaction/methods , Polymorphism, Restriction Fragment Length/genetics , Polymorphism, Single Nucleotide/genetics , Young Adult
10.
Aliment Pharmacol Ther ; 48(5): 523-537, 2018 09.
Article in English | MEDLINE | ID: mdl-29984520

ABSTRACT

BACKGROUND: Risk benefit strategies in managing inflammatory bowel diseases (IBD) are dependent upon understanding the risks of uncontrolled inflammation vs those of treatments. Malignancy and mortality in IBD have been associated with disease-related inflammation and immune suppression, but data are limited due to their rare occurrence. AIM: To identify and describe the most common causes of mortality, types of cancer and previous or current therapy among children and young adults with paediatric-onset IBD. METHODS: Information on paediatric-onset IBD patients diagnosed with malignancy or mortality was prospectively collected via a survey in 25 countries over a 42-month period. Patients were included if death or malignancy occurred after IBD diagnosis but before the age of 26 years. RESULTS: In total, 60 patients were identified including 43 malignancies and 26 fatal cases (9 due to cancer). Main causes of fatality were malignancies (n = 9), IBD or IBD-therapy related nonmalignant causes (n = 10; including 5 infections), and suicides (n = 3). Three cases, all fatal, of hepatosplenic T-cell lymphoma were identified, all were biologic-naïve but thiopurine-exposed. No other haematological malignancies were fatal. The 6 other fatal cancer cases included 3 colorectal adenocarcinomas and 3 cholangiocarcinomas (CCAs). Primary sclerosing cholangitis (PSC) was present in 5 (56%) fatal cancers (1 colorectal carcinoma, 3 CCAs and 1 hepatosplenic T-cell lymphoma). CONCLUSIONS: We report the largest number of paediatric-onset IBD patients with cancer and/or fatal outcomes to date. Malignancies followed by infections were the major causes of mortality. We identified PSC as a significant risk factor for cancer-associated mortality. Disease-related adenocarcinomas were a commoner cause of death than lymphomas.


Subject(s)
Inflammatory Bowel Diseases/complications , Inflammatory Bowel Diseases/mortality , Neoplasms/complications , Neoplasms/mortality , Adolescent , Adult , Age of Onset , Child , Child, Preschool , Europe/epidemiology , Female , Humans , Infant , Infant, Newborn , Inflammatory Bowel Diseases/epidemiology , Male , Neoplasms/epidemiology , Prospective Studies , Risk Assessment , Risk Factors , Young Adult
11.
Mol Cell Biol ; 7(11): 3916-22, 1987 Nov.
Article in English | MEDLINE | ID: mdl-2828919

ABSTRACT

Ornithine carbamoyl transferase (Oct) is an X-linked gene which exhibits tissue-specific expression. To determine whether methylation of specific CpG sequences plays a role in dosage compensation or tissue-specific expression of the gene, 13 potentially methylatable sites were identified over a 30-kilobase (kb) region spanning from approximately 15 kb upstream to beyond exon II. Fragments of the Mus hortulanus Oct gene were used as probes to establish the degree of methylation at each site. By considering the methylation status in liver (expressing tissue) versus kidney (nonexpressing tissue) from male and female mice, the active and inactive genes could be investigated on active and inactive X-chromosome backgrounds. One MspI site, 12 kb 5' of the Oct-coding region, was cleaved by HpaII in liver DNA from males but not in kidney DNA from males and thus exhibited complete correlation with tissue-specific expression of the gene. Six other sites showed partial methylation, reflecting incomplete correlation with tissue-specific expression.


Subject(s)
Genes , Ornithine Carbamoyltransferase/genetics , X Chromosome , Animals , Cloning, Molecular , DNA/genetics , DNA/metabolism , DNA Restriction Enzymes , Female , Kidney/enzymology , Liver/enzymology , Male , Methylation , Muridae , Sex Factors
12.
Hum Gene Ther ; 12(4): 401-13, 2001 Mar 01.
Article in English | MEDLINE | ID: mdl-11242532

ABSTRACT

The methods available to efficiently transduce human CD34(+) hematopoietic stem cells (HSCs) derived from mobilized peripheral blood, such that they fully retain their engraftment potential and maintain high levels of transgene expression in vivo, have been unsatisfactory. The current murine retrovirus-based gene transfer systems require dividing cells for efficient transduction, and therefore the target HSCs must be activated ex vivo by cytokines to cycle, which may limit their engrafting ability. Lentivirus-based gene transfer systems do not require cell division and, thus, may allow for efficient gene transfer to human HSCs in the absence of any ex vivo cytokine stimulation. We constructed human immunodeficiency virus (HIV)-based vectors and compared them in vitro and in vivo with MuLV-based vectors in their ability to transduce unstimulated human CD34(+) HSCs isolated from mobilized peripheral blood. Both sets of vectors contained the marker gene that expresses the enhanced green fluorescent protein (EGFP) for evaluating transduction efficiency and were pseudotyped with either vesicular stomatitis virus glycoprotein (VSV-G) or the amphotropic murine leukemia virus envelope (A-MULV Env). The VSV-G-pseudotyped HIV-based vectors containing an internal mouse phosphoglycerate kinase promoter (PGK) were able to transduce up to 48% of the unstimulated CD34(+) cells as measured by EGFP expression. When these cells were injected into the human fetal thymus implants of irradiated SCID-hu Thy/Liv mice, up to 18% expressed EGFP after 8 weeks in vivo. In contrast, the MULV-based vectors were effective at transducing HSCs only in the presence of cytokines. Our results demonstrate that the improved HIV-based gene transfer system can effectively transduce unstimulated human CD34(+) HSCs, which can then differentiate into thymocytes and provide long-term transgene expression in vivo.


Subject(s)
Antigens, CD34/metabolism , HIV-1/genetics , Hematopoietic Stem Cells/virology , T-Lymphocytes/metabolism , Transgenes/genetics , Animals , Cell Line , Cytokines/pharmacology , Disease Models, Animal , Gene Dosage , Genetic Vectors , Green Fluorescent Proteins , Hematopoietic Stem Cells/immunology , Humans , Leukemia Virus, Murine/genetics , Leukemia Virus, Murine/physiology , Liver/physiology , Liver/radiation effects , Luminescent Proteins/metabolism , Mice , Mice, SCID/genetics , Mice, SCID/metabolism , Phosphoglycerate Kinase/genetics , Polymerase Chain Reaction , Promoter Regions, Genetic , T-Lymphocytes/immunology , Thymus Gland/physiology , Thymus Gland/radiation effects , Transduction, Genetic , Vesicular stomatitis Indiana virus/genetics , Vesicular stomatitis Indiana virus/physiology , Viral Envelope Proteins/genetics , Virus Replication
13.
Hum Gene Ther ; 5(2): 193-201, 1994 Feb.
Article in English | MEDLINE | ID: mdl-8186299

ABSTRACT

We have previously reported that chimeric neomycin phosphotransferase (neo)-Rev response element (RRE) transcripts suppress the function of the human immunodeficiency virus type 1 (HIV-1) Rev trans-activator protein in HeLa cells. In an extension of these experiments, human CD4+ CEM cells (G418-resistant cell populations and clonal isolates) stably expressing chimeric neo-RRE genes (2, 3, or 6 RRE copies) were generated using retroviral-mediated gene transfer. The transduced CEM clones were infected with the HIV-1 HTLVIIIB isolate and the following three phenotypes were observed: (i) the transduced CEM cells were readily infected with HIV-1 indistinguishable from the control CEM cells; (ii) the appearance of HIV-1 replication markers was significantly delayed; (iii) no signs of HIV-1 replication were detectable although proviral HIV-1 DNA sequences could be detected in these cells. Furthermore, HIV antigen expression was limited in neo-resistant CEM cell populations inoculated with the HIV-1 HTLVIIIB isolate. Only 10% of the CEM-pX17-3xRRE cells and 20% of the CEM-pX17-2xRRE cells displayed HIV-1 antigens 43 days after challenge and had retained CD4 surface expression on 47% and 64% of the cells, respectively. In sharp contrast, 80% of the CEM-pX17 or the CEM-pX17-6xRRE cells expressed HIV-1 antigens but no CD4 antigens were detectable in these cultures. These results clearly indicate that RRE decoys could be developed into an effective somatic gene therapy approach against HIV-1 induced acquired immunodeficiency syndrome (AIDS).


Subject(s)
Gene Products, rev/biosynthesis , Genetic Therapy/methods , HIV-1/physiology , Recombinant Fusion Proteins/biosynthesis , T-Lymphocytes/microbiology , Virus Replication , Base Sequence , CD4 Antigens/biosynthesis , Cell Line , DNA, Viral/isolation & purification , Gene Products, rev/genetics , Gene Products, rev/physiology , HIV-1/genetics , HIV-1/isolation & purification , HeLa Cells , Humans , Kanamycin Kinase , Molecular Sequence Data , Phenotype , Phosphotransferases (Alcohol Group Acceptor)/biosynthesis , Phosphotransferases (Alcohol Group Acceptor)/genetics , Proviruses/isolation & purification , Recombinant Fusion Proteins/genetics , Transfection , rev Gene Products, Human Immunodeficiency Virus
14.
Gene ; 171(2): 203-8, 1996 Jun 01.
Article in English | MEDLINE | ID: mdl-8666273

ABSTRACT

Retroviral gene delivery systems for RNA polymerase II (RNA pol II)-based promoters have been developed and are widely used in gene transfer studies. In contrast, gene delivery systems with RNA pol III-based expression cassettes have not been studied comprehensively, although therapeutic applications (e.g., ribozymes, antisense, triplex RNA and RNA decoys) have been proposed. In this report, we describe retroviral vectors designed to optimize expression of short chimeric RNAs transcribed from a number of RNA pol III promoters. Our results show that all analysed RNA pol III expression cassettes (tRNA, U6, Ad VA1), regardless of orientation, do not transcribe efficiently when located between the retroviral long terminal repeats (LTRs). In contrast, high steady-state expression levels can be achieved by inserting the RNA pol III expression cassette into the U3 region of the LTR (double-copy design). Compared to human tRNA gene promoters (tRNA(Met), tRNA(Val)), the human small nuclear RNA U6 gene (U6) and the adenovirus virus-associated RNA 1 (Ad VA1) gene promoters yielded higher expression levels. The majority of the chimeric U6-derived transcripts were detected in the nuclear RNA fraction, and the VA1 and tRNA-driven transcripts were predominantly detected in the cytoplasmic compartments. This report is the first comparative study of RNA pol III-driven promoters expressing short chimeric transcripts leading to an optimized retroviral-vector design.


Subject(s)
Genetic Vectors/genetics , RNA Polymerase III/genetics , Retroviridae/genetics , Adenoviridae/genetics , Animals , Cell Line , Gene Products, rev/genetics , Genetic Vectors/chemistry , HIV/genetics , HeLa Cells , Humans , Mice , Promoter Regions, Genetic , RNA Polymerase III/biosynthesis , RNA, Catalytic/genetics , RNA, Transfer, Met/genetics , RNA, Transfer, Val/genetics , RNA, Viral , Recombinant Proteins/genetics , Ribonucleoprotein, U4-U6 Small Nuclear/genetics , Subcellular Fractions , Transcription, Genetic , Transcriptional Activation , Transduction, Genetic , rev Gene Products, Human Immunodeficiency Virus
15.
FEBS Lett ; 184(2): 299-303, 1985 May 20.
Article in English | MEDLINE | ID: mdl-3996588

ABSTRACT

Hypoxanthine-guanine phosphoribosyltransferase enzyme (EC 2.4.2.8) from chicken brain has been purified 10 000-fold to homogeneity. The molecular mass of the native enzyme is 85 kDa, with four subunits, each of 26 kDa, and exerts its maximum activity at pH 10.0. The Km values for hypoxanthine and guanine are 5.2 and 1.8 microM, respectively. The half-life of the enzyme is 30 min at 85 degrees C. Monoclonal antibodies were raised against the native purified enzyme and were used for purification of enzyme to homogeneity. The monoclonal antibody did not bind to the active centre of the enzyme.


Subject(s)
Brain/enzymology , Hypoxanthine Phosphoribosyltransferase/isolation & purification , Animals , Chickens , Cross Reactions , Hypoxanthine Phosphoribosyltransferase/immunology , Hypoxanthine Phosphoribosyltransferase/metabolism , Kinetics , Molecular Weight
16.
AIDS Res Hum Retroviruses ; 13(16): 1395-402, 1997 Nov 01.
Article in English | MEDLINE | ID: mdl-9359659

ABSTRACT

Gene therapy for the treatment of human immunodeficiency virus type 1 (HIV-1) infection using intracellular immunization strategies is currently being tested in clinical trials. With the continuing development of potent antiretroviral drugs (e.g., reverse transcriptase [RT] and protease [PR] inhibitors), it is likely that HIV-1 gene therapy will be applied to humans concurrently receiving such antiretroviral medication. In this study, we assessed the in vitro antiviral efficacy of two gene therapy strategies (trans-dominant RevM10, Gag antisense RNA) in combination with clinically relevant RT (AZT, ddC) or PR (indinavir) inhibitors. Retrovirally transduced, human T cell lines expressing antiviral gene constructs were inoculated with high doses of HIV-1HXB3 in the presence or absence of inhibitors. The combination of RevM10 or Gag antisense RNA with antiviral drugs inhibited HIV-1 replication 10-fold more effectively than the single antiviral drug regimen alone. More importantly, we also addressed whether gene therapy strategies are effective against drug-resistant HIV-1 isolates. Both the RevM10 and Gag antisense RNA strategies showed antiviral efficacy against several RT inhibitor-resistant HIV-1 isolates equivalent to their inhibition of HIV-1HXB3 replication. In summary, our data demonstrate the greater than additive antiviral efficacy of gene therapy strategies and RT or PR inhibitors, and that gene therapy approaches are effective against drug-resistant HIV-1 viral isolates.


Subject(s)
Acquired Immunodeficiency Syndrome/therapy , Anti-HIV Agents/therapeutic use , Genetic Therapy , HIV-1/drug effects , HIV-1/genetics , Cell Line , Combined Modality Therapy , DNA, Recombinant , Dose-Response Relationship, Drug , Gene Products, gag/genetics , Gene Products, gag/physiology , Gene Products, rev/genetics , Gene Products, rev/physiology , Genetic Vectors/genetics , Genome, Viral , HIV Core Protein p24/drug effects , HIV Core Protein p24/metabolism , HIV-1/growth & development , Humans , Indinavir/therapeutic use , RNA, Antisense/genetics , RNA, Antisense/physiology , T-Lymphocytes/cytology , T-Lymphocytes/drug effects , T-Lymphocytes/virology , Zalcitabine/administration & dosage , Zalcitabine/therapeutic use , Zidovudine/administration & dosage , Zidovudine/therapeutic use , rev Gene Products, Human Immunodeficiency Virus
17.
Bone Marrow Transplant ; 34(3): 221-8, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15170168

ABSTRACT

Intestinal immunopathology was studied after allogeneic stem cell transplantation (SCT) in a common clinical setup in 20 children with malignant (n=17) or nonmalignant diseases (n=3) receiving grafts from siblings (7) and unrelated donors (13). In all, 19 had total body irradiation. Duodenal biopsies at 6 and 12 weeks post transplant were evaluated by histology, immunohistochemistry, and ISEL for the detection of T-lymphocytes, inflammatory cytokines, proliferation, and apoptosis. The controls were 12 healthy children and three patients with proven intestinal graft-versus-host disease. An increased rate of apoptosis and proliferation with upregulated expression of HLA-DR antigen was detected up to 3 months post transplant in the SCT patients, even in those with a histologically normal small intestine. A low level of IFNgamma and TNFalpha was observed in the lamina propria. The initial low density of gammadelta-positive T cells had recovered to normal by the time of the second endoscopy at 12 weeks post transplant. We conclude that inflammatory activity and T cell infiltration detected by immunohistochemistry may not belong to the 'normal' recovery of the small intestine after SCT. Increased cell turnover in the intestinal crypts continues until 3 months after SCT, suggesting either an unexpectedly long-lasting effect of transplant-related toxicity or, preferably, an ongoing subclinical alloreactive process, also present in the patients without intestinal symptoms.


Subject(s)
Cytokines/metabolism , Duodenum/immunology , Graft vs Host Disease/immunology , Lymphocytes, Tumor-Infiltrating/immunology , Stem Cell Transplantation , T-Lymphocytes/immunology , Transplantation, Homologous/immunology , Adolescent , Cell Division , Child , Child, Preschool , Female , Gene Expression Regulation, Neoplastic/immunology , Graft vs Host Disease/pathology , HLA-DR Antigens/genetics , Humans , Infant , Inflammation , Male , Neoplasms/immunology , Neoplasms/therapy , Transplantation, Homologous/pathology , Whole-Body Irradiation
18.
Virchows Arch ; 428(3): 187-94, 1996 Jun.
Article in English | MEDLINE | ID: mdl-8688973

ABSTRACT

We investigated the reaction of the cellular immune system of liver and blood in the C57BL/6 mouse to a metastasizing Lewis lung carcinoma. The cellular immune system of the liver consists of mature and immature macrophages, B-cells, T-cells including their subpopulations, and natural killer cells, and their percentage frequencies differ significantly from those in the corresponding mononuclear blood cell (MBC) compartment. This suggests that the hepatic immune cells represent a system with autonomous function showing a typical homing of its members. Imminent metastasis to the liver is signalled by impressive alterations in the percentage frequencies of nonparenchymal liver cells (NPLC). There are a dramatic loss of mature macrophages, an increase in immature macrophages, a reduction of T-helper cells leading to a low CD4/CD8 ratio, and an increase in natural killer cells. In the blood, the corresponding precursor cells show comparable changes with a delay of at least 2 days. Early metastasis is accompanied by a significant increase in mononuclear NPLC producing tumour necrosis factor alpha. The alterations in percentage frequencies of the NPLC during tumour metastasis differ markedly from the changes in these cells in the liver during endotoxinaemia.


Subject(s)
Liver Neoplasms/immunology , Liver Neoplasms/secondary , Liver/immunology , Lung Neoplasms/immunology , Animals , B-Lymphocytes/immunology , CD4-CD8 Ratio , Cell Count , Female , Immunohistochemistry , Liver/ultrastructure , Lymphocyte Count , Macrophages/immunology , Male , Mice , Mice, Inbred C57BL , Microscopy, Electron , T-Lymphocytes/immunology , T-Lymphocytes, Helper-Inducer/immunology , Tumor Necrosis Factor-alpha/analysis
19.
Phys Rev E Stat Nonlin Soft Matter Phys ; 64(1 Pt 2): 016410, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11461413

ABSTRACT

X-ray self-emission of radiatively heated materials with different values of Z has been investigated. Thin foils were uniformly heated by a 120-eV Hohlraum radiation of 400-ps duration in order to study the self-emission of a homogeneous, optically thin material. The x-ray emission spectra were followed for more than 2 ns. The spectrally integrated emission shows not only a strong Z dependence, but different temporal behaviors for different values of Z. The lower is the value of Z of the x-ray heated matter, the longer is the duration of self-emission. Theoretical comparison with a hydrocode and FLY post-processing shows a non-local-thermal equilibrium behavior caused by direct photoionization due to the thermal pumping radiation, which has a higher brightness temperature than the matter temperature of the heated material.

20.
Prosthet Orthot Int ; 1(3): 161-72, 1977 Dec.
Article in English | MEDLINE | ID: mdl-617372

ABSTRACT

Application of a graphical technique to analyse internal forces on a simplified model of the foot in various external loading patterns. The method is applied when the external load is acting purely upon the forefoot, the hindfoot and on both locations. The pes planus situation and the effect of the "rocker" and inlay sole are studied.


Subject(s)
Biomechanical Phenomena , Foot/physiopathology , Body Weight , Flatfoot/physiopathology , Flatfoot/rehabilitation , Humans , Movement , Postural Balance , Shoes
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