Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038362 (stomatitis)
 8,852 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The major limitations of Moloney murine leukemia virus (MoMLV)-based vectors for human stem cell applications, particularly those requiring bone marrow (BM) stem cells, include their requirement for mitosis and retroviral receptor expression. New vectors based upon lentiviruses such as HIV-1 exhibit properties that may circumvent these problems. We report that novel third-generation, self-inactivating lentiviral vectors, expressing enhanced green fluorescent protein (EGFP) and pseudotyped with vesicular stomatitis virus G glycoprotein (VSV-G), can efficiently transduce primitive human repopulating cells derived from human BM and cord blood (CB) tested by the SCID-repopulating cell (SRC) assay. Highly purified CD34+ CD38- CB or BM cells were efficiently transduced (4-69%) and stably expressed in EGFP for 40 days in culture following infection for only 24 h without fibronectin, polybrene, or cytokines. Nonobese diabetic/severe combined immune-deficient (NOD/SCID) mice transplanted with transduced cells from either CB or BM donors were well engrafted, demonstrating maintenance of SRC during the infection procedure. Serially obtained femoral BM samples indicated that the proportion of EGFP+ cells within both myeloid and lymphoid lineages was maintained or even increased over time, averaging 42.3 +/- 6.6% for BM donors and 23.3 +/- 7.2% for CB at 12 weeks. Thus, the third-generation lentivectors readily transduce human CB and BM stem cells, under minimal conditions of ex vivo culture, where MoMLV-based vectors are ineffective. Since CB is inappropriate for most therapeutic applications, the efficient maintenance and transduction of BM-derived SRC during the short infection procedure are notable advantages of lentivectors.
Mol Ther 2000 Jun
PMID:Transduction of human CD34+ CD38- bone marrow and cord blood-derived SCID-repopulating cells with third-generation lentiviral vectors. 1093 81

Lentiviral vectors open exciting perspectives for the genetic treatment of a wide array of inherited and acquired diseases, owing to their ability to govern the efficient delivery, integration, and long-term expression of transgenes into nondividing cells both in vitro and in vivo. The genomic complexity of HIV, where a whole set of genes encode virulence factors essential for pathogenesis but not required for gene transfer, allowed a major step toward clinical acceptability through the creation of multiply attenuated packaging systems. Until now, however, vector particles could only be produced by transient transfection because no high-output, stable packaging cell line was available that produced the latest generation of HIV-based vectors. Here we describe such a line, based on the doxycycline-repressible expression of HIV-1 Rev/Gag/Pol and of the vesicular stomatitis virus G envelope (VSV G) in 293 human embryonic kidney cells. Upon induction, the LVG clones can produce 1 to 20 HeLa-transducing units per cell per day for about a week, a yield that compares favorably with that of transiently transfected 293T cells. These virions exhibit functional properties similar to those of viruses produced transiently, in particular the ability to transduce nonmitotic targets. This system will facilitate the further development of lentiviral vectors for gene therapy.
Mol Ther 2000 Aug
PMID:A stable system for the high-titer production of multiply attenuated lentiviral vectors. 1094 45

The matrix (M) protein of vesicular stomatitis virus (VSV) is a potent inhibitor of bidirectional nuclear transport. Here we demonstrate that inhibition occurs when M protein is in the nucleus of Xenopus laevis oocytes and that M activity is readily reversed by a monoclonal antibody (alphaM). We identify a region of M protein, amino acids 51 to 59, that is required both for inhibition of transport and for efficient recognition by alphaM. When expressed in transfected HeLa cells, M protein colocalizes with nuclear pore complexes (NPCs) at the nuclear rim. Moreover, mutation of a single amino acid, methionine 51, eliminates both transport inhibition and targeting to NPCs. We propose that M protein inhibits bidirectional transport by interacting with a component of the NPC or an NPC-associated factor that participates in nucleocytoplasmic transport.
Mol Cell Biol 2000 Nov
PMID:The matrix protein of vesicular stomatitis virus inhibits nucleocytoplasmic transport when it is in the nucleus and associated with nuclear pore complexes. 1104 54

Many life-threatening conditions that can be diagnosed early in gestation may be treatable in utero using gene therapy. In order to determine in utero gene transfer efficiency and safety, studies were conducted with fetal rhesus monkeys as a model for the human. Included in these studies were Moloney murine leukemia virus (MLV)-based amphotropic retrovirus, vesicular stomatitis virus-G (VSV-G) pseudotyped MLV, and a VSV-G pseudotyped HIV-1-based vector, all expressing the enhanced green fluorescent protein (EGFP) as a reporter gene and driven by a cytomegalovirus-immediate early promoter (N = 16). Rhesus monkey fetuses were administered viral vector supernatant preparations by the intraperitoneal (ip) (N = 14) or intrahepatic (ih) (N = 2) routes via ultrasound guidance at 55 +/- 5 days gestation (late first trimester; term 165 +/- 10 days). Fetuses were monitored sonographically, specimens were collected prenatally and postnatally, and tissue harvests were performed at birth or 3 or 6 months postnatal age (3-10 months post-gene transfer). PCR analyses demonstrated that transduced cells were present at approximately 1.2% in peripheral blood mononuclear cells from fetuses administered amphotropic MLV, <0.5% in fetuses receiving MLV/VSV-G, and approximately 4.2% for the lentiviral vector, which decreased to 2% at birth. Hematopoietic progenitors showed that overall (mean of all time points assessed), approximately 25% of the collected colonies were positive for the EGFP transgene with the lentiviral vector, which was significantly greater than results achieved with the MLV-based vector systems (4-9%; P < or = 0.001-0.016). At necropsy, 0.001-10% of the total genomic DNA was positive for EGFP in most tissues for all groups. EGFP-positive fluorescent cells were found in cell suspensions of thymus, liver, spleen, lymph nodes, cerebral cortex, and bone marrow (0.5-6%). Overall, the results of these studies have shown: (1) healthy infants expressing vector sequences up to 10 months post-gene transfer, (2) fetal primate administration of retroviral vectors results in gene transfer to multiple organ systems, (3) the highest level of gene transfer to hematopoietic progenitors was observed with the lentiviral vector system, and (4) there was no evidence of transplacental transfer of vector sequences into the dams. The rhesus monkey is an important preclinical primate model system for exploring gene transfer approaches for future applications in humans.
Mol Ther 2001 Feb
PMID:Rhesus monkey model for fetal gene transfer: studies with retroviral- based vector systems. 1123 85

The quasispecies model of RNA virus evolution differs from those formulated in conventional population genetics in that neutral mutations do not lead to genetic drift of the population, and natural selection acts on the mutant distribution as a whole rather than on individual variants. By computer simulation, we show that this model could be inappropriate for many RNA viruses because the neutral sequence space may be too large to allow the formation of a quasispecies distribution. This view is supported by our analysis of gene sequences from vesicular stomatitis virus, which is considered a prototype RNA virus quasispecies. Our results are relevant to the evolution of RNA systems in general.
Mol Biol Evol 2001 Jun
PMID:Evidence for the non-quasispecies evolution of RNA viruses [corrected]. 1137 87

The replicative fitness of a genetically marked (MARM-C) population of vesicular stomatitis virus was examined in competition assays in BHK-21 cells. In standard fitness assays involving up to eight competition passages of the mixed populations, MARM-C competes equally with the wild type (wt), but very prolonged competitions always led to the wt gaining dominance over MARM-C in a very slowed, nonlinear manner (J. Quer et al., J. Mol. Biol. 264:465-471, 1996). In the present study we show that a number of quite unrelated environmental perturbations, which decreased virus replication during competitions, all led to an accelerated dominance of the wt over MARM-C. These perturbations were (i) the presence of added (or endogenously generated) defective interfering particles, (ii) the presence of the chemical mutagen 5-fluorouracil (5-FU), or (iii) an increase in temperature to 40.5 degrees C. Thus, the "neutral fitness" of the MARM-C population is contingent. We have determined the entire genomic consensus sequence of MARM-C and have identified only six mutations. Clearly, some or all of these mutations allowed the MARM-C quasispecies population to compete equally with wt in a defined constant host environment, but the period of neutrality was shortened when the environment was perturbed during competitions. Interestingly, when four passages of each population were carried out independently in the presence of 5-FU (but in the absence of competition), no significant differences were detected in the fitness changes of wt and MARM-C, nor was there a difference in their subsequent abilities to compete with each other in a standard fitness assay. We propose a model for this contingent neutrality. The conditions employed to generate the MARM-C quasispecies population selected a small number of mutations in the consensus sequence. It appears that the MARM-C quasispecies population has moved into a segment of sequence space in which the average fitness value is neutral but, under environmental stress, beneficial mutations cannot be generated rapidly enough to compete with those being generated concurrently by competing wt virus quasispecies populations.
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PMID:Contingent neutrality in competing viral populations. 1146 3

We investigated the production efficiency and the gene transfer capacity in the central nervous system of HIV-1-based vectors pseudotyped with either the G protein of the Mokola lyssaviruses (MK-G), a neurotropic virus causing rabies disease, or the vesiculo-stomatitis G protein (VSV-G). Both envelopes induced syncitia in cell cultures. They were incorporated into vector particles and mature virions were observed by electron microscopy. Vector production was two- to sixfold more efficient with VSV-G than with MK-G. For equivalent amounts of physical particles, vector titration was 5- to 25-fold higher with VSV-G than with MK-G pseudotypes on cultured cells, and in vivo gene expression in mouse brain was more intense. Thus, VSV-G pseudotypes were produced more efficiently and were more infectious than MK-G pseudotypes. Tropism for brain cells was analyzed by intrastriatal injections in rats. Both pseudotypes preferentially transduced neurons (70-90% of transduced cells). Retrograde axonal transport was investigated by instilling vector suspensions in the rat nasal cavity. Both pseudotypes were efficiently transported to olfactive neuron bodies. Thus, although coating HIV-1 particles with rabdhovirus envelope glycoproteins enables them to enter neuronal cells efficiently, pseudotyping is not sufficient to confer the powerful neurotropism of lyssaviruses to lentivirus vectors.
Mol Ther 2001 Aug
PMID:Production and neurotropism of lentivirus vectors pseudotyped with lyssavirus envelope glycoproteins. 1148 87

The advent of reverse-genetics represents a powerful new approach to elucidate aspects of negative-sense RNA virus replication. The reverse-genetics system established previously for vesicular stomatitis virus (VSV) required four plasmids encoding the nucleoprotein (N), phosphoprotein (P), polymerase (L), and the full-length, anti-genomic RNA. Transcription to yield the antigenomic RNA as well as the N, P, and L, mRNAs was initiated by bacteriophage T7 polymerase expressed from a recombinant Vaccinia virus. In this report, we describe the successful recovery of infectious VSV in the absence of Vaccinia virus. The N, P, and L genes of VSV were inserted downstream of both the T7 promoter and an internal ribosomal entry site (IRES element). T7 polymerase was expressed constitutively from BSR-T7/5 cells. RTPCR was used to confirm that the recovered VSV was derived from transfected DNA. Virion protein profile, CPE in tissue culture, and virus titer of the recombinant VSV were indistinguishable from those of parental VSV. Thus, the need for Vaccinia virus is eliminated with this system, making it an attractive, alternative approach for the recovery of infectious VSV from DNA.
J Mol Microbiol Biotechnol 2001 Oct
PMID:Vaccinia virus-free recovery of vesicular stomatitis virus. 1154 70

We have previously shown that vesicles containing the spike glycoprotein of the vesicular stomatitis virus (VSV-G) can associate efficiently with immature, non-infectious, envelope-deficient retrovirus-like particles assembled by packaging cells to produce infectious, pseudotyped viruses in cell-free conditions in vitro. We have also previously reported that VSV-G can enhance DNA lipofection efficiency by interacting with liposomes to form fusogenic, serum-stable liposomes with enhanced transfection properties. Here, we report that VSV-G can form a complex directly with naked plasmid DNA in the absence of a lipofection reagent and can thereby enhance the transfection efficiency of the naked plasmid vector. Sucrose gradient sedimentation analysis demonstrated that VSV-G can also associate with plasmid DNA and murine leukemia virus (MLV) gag-pol particles to form ternary complexes that co-sediment with high DNA transfecting activity. The increased transfection efficiency with VSV-G was dependent on the presence of the polycation (Polybrene) in the culture medium during transfection. Enhanced transfection was abolished by a neutralizing antibody to VSV-G. These results may be useful in the study of retrovirus assembly, in the further design of hybrid DNA-based retrovirus-like vectors, and in the full in vitro, cell-free assembly of infectious virus-like particles from component parts.
Mol Ther 2001 Sep
PMID:VSV-G envelope glycoprotein forms complexes with plasmid DNA and MLV retrovirus-like particles in cell-free conditions and enhances DNA transfection. 1154 14

In this report it is demonstrated for the first time that rabies-G envelope of the rabies virus is sufficient to confer retrograde axonal transport to a heterologous virus/vector. After delivery of rabies-G pseudotyped equine infectious anaemia virus (EIAV) based vectors encoding a marker gene to the rat striatum, neurons in regions distal from but projecting to the injection site, such as the dopaminergic neurons of the substantia nigra pars compacta, become transduced. This retrograde transport to appropriate distal neurons was also demonstrated after delivery to substantia nigra, hippocampus and spinal cord and did not occur when vesicular stomatitis virus glycoprotein (VSV-G) pseudotyped vectors were delivered to these sites. In addition, peripheral administration of rabies-G pseudotyped vectors to the rat gastrocnemius muscle leads to gene transfer in motoneurons of lumbar spinal cord. In contrast the same vector pseudotyped with VSV-G transduced muscle cells surrounding the injection site, but did not result in expression in any cells in the spinal cord. Long-term expression was observed after gene transfer in the nervous system and a minimal immune response which, together with the possibility of non-invasive administration, greatly extends the utility of lentiviral vectors for gene therapy of human neurological disease.
Hum Mol Genet 2001 Sep 15
PMID:Rabies virus glycoprotein pseudotyping of lentiviral vectors enables retrograde axonal transport and access to the nervous system after peripheral delivery. 1159 Jan 28


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