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)

We examined the effects of polycations, namely, diethylaminoethyl-dextran (DEAE-dextran) and hexadimethrine bromide (Polybrene), on infection with the retroviruses human T cell leukemia virus types I and II (HTLV-I and HTLV-II) and human immunodeficiency virus type 1 (HIV-1). The plating of vesicular stomatitis virus (VSV) pseudotype bearing envelope antigens of HTLV-I [VSV(HTLV-I)] was inhibited about 2- and 10-fold by treatment with DEAE-dextran and Polybrene, respectively. The formation of HTLV-I viral DNA detected 1 day after infection was also inhibited by these polycations. In contrast, polycations enhanced the plating of the VSV (HTLV-II) pseudotype two- to threefold. The polycations did not affect the plating efficiency of HTLV-I or HTLV-II when added after virus adsorption. Infection of human T cell lines, peripheral blood lymphocytes (PBLs), or brain-derived cells with syncytium-inducing (SI) types of HIV-1 strains (GUN1 and IIIB) was inhibited 3- to 20-fold by polycations. However, infection of PBLs or monocyte-derived macrophages with the macrophage-tropic Ba-L or SF162 strain was enhanced 1.5- to twofold by polycations. On the other hand, syncytium formation in coculture induced by HTLV-I, HTLV-II, or HIV-1 was enhanced two- to threefold unanimously by DEAE-dextran or Polybrene. Although polycations have been used to potentiate human retrovirus adsorption, they inhibited infection of cell-free HTLV-I or SI-type HIV-1 strains.
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PMID:Inhibition of plating of human T cell leukemia virus type I and syncytium-inducing types of human immunodeficiency virus type 1 by polycations. 939 Jul 51

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.
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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

Lentiviral vectors may improve hematopoietic stem cell (HSC) gene transfer because of their enhanced ability to transduce nondividing cells. However, many studies report efficient transduction only at high multiplicities of infection (MOI). This study reports efficient transduction of human CD34(+) cells with a drug resistance gene allowing post-transduction selection using lentivirus under low-MOI conditions that did not require cytokine stimulation or viral concentration. We used the P140K methylguanine-DNA-methyltransferase mutant (P140K MGMT) as the gene insert into a second-generation lentiviral backbone and triple-plasmid transfection to generate vesicular stomatitis virus (VSV)-G protein-pseudotyped virus. The P140K MGMT gene product, O(6)-alkylguanine-DNA-alkyltransferase (AGT), provides protection from the therapeutic drug combination of 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) and the wild-type AGT inhibitor O(6)-benzylguanine (BG). Low-speed spinoculation enhanced transduction more than addition of Polybrene or multiple virus exposures. Addition of cytokines was not required. Low-MOI transduction (< or =1) of human CD34(+) and CD34(+) lin(-) cells with P140K MGMT lentivirus resulted in an average 41% and 89% gene transfer rate as assessed by PCR, respectively, and concordant AGT expression that conferred substantial clonogenic survival advantage after BG/BCNU treatment. During in vitro drug selection, 87% of surviving CD34(+) cell-derived colony-forming units (CFU) were transduced. This work shows the potential utility of lentiviral vectors for drug resistance gene transfer to HSCs for the purpose of in vivo selection and marrow protection. Because drug selection will enrich for transduced progenitors, high MOI can be avoided, improving the safety profile of lentiviral gene transfer.
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PMID:Lentiviral transduction of P140K MGMT into human CD34(+) hematopoietic progenitors at low multiplicity of infection confers significant resistance to BG/BCNU and allows selection in vitro. 1194 64

Non-infectious, envelope protein-free, retrovirus-like particles (VLP) derived from either Moloney murine leukemia virus (MLV) or human HIV are able to bind efficiently to, but not infect, target cells. Upon subsequent addition to the bound particles of the G protein of vesicular stomatitis virus (VSV-G), an efficient surrogate retrovirus envelope protein, the VLP are efficiently taken up by the cells to produce infection. Cell attachment of the VLP is efficiently inhibited by soluble heparin and dextran sulfate and less efficiently abrogated by several other glycosaminoglycans (GAGs) including chondroitin sulfate A and chondroitin sulfate B (dermatan sulfate), as determined by deconvolution microscopic immunodetection of the viral gag protein and by quantitative binding studies of metabolically labeled (35)S-VLP. Enzymatic digestion of heparan sulfate (HS) from the cell surface with heparinase I also reduces VLP binding. Furthermore, VLP adsorption onto several CHO cell lines variably deficient in cell surface GAG is significantly but incompletely abrogated. De-sulfated heparins are less efficient than native heparin in inhibiting the Polybrene-mediated binding of VLP, whereas growth of human cells in the presence of sodium chlorate leads to significant reduction of Polybrene-mediated VLP binding. In addition, specific inhibition of VLP binding and infectivity of mature infectious VSV-G-pseudotyped virus is observed in the presence of heparin and HS under Polybrene-free conditions. We conclude from these studies that the presence of Polybrene, the degree of sulfation of cell surface GAG, and possibly the presence of charged cell surface macromolecules create an electrostatic environment that promotes optimum binding of VLP to cells. Additionally, our results demonstrate that, in the absence of Polybrene, initial attachments of non-infectious, envelope protein-free VLP and probably mature infectious virus particles are mediated by interactions of the virus particles with cell surface heparan sulfate, and possibly with other GAG molecules.
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PMID:Cell surface heparan sulfate is a receptor for attachment of envelope protein-free retrovirus-like particles and VSV-G pseudotyped MLV-derived retrovirus vectors to target cells. 1199 44

Ross River virus (RRV) and Semliki Forest virus (SFV) are two alphaviruses that have a high degree of amino acid homology, as well as a very broad host range. We show here that envelope glycoproteins derived from both viruses can pseudotype human immunodeficiency virus type 1 (HIV-1)-derived lentivirus vectors. Both RRV and SFV glycoproteins considerably expand the host range of the lentivirus vector, and vectors can be efficiently concentrated by ultracentrifugation. A systematic analysis comparing the alphaviral glycoproteins to the vesicular stomatitis virus glycoprotein (VSV-G) revealed that lentivirus vectors incorporate RRV glycoproteins with an efficiency comparable to that of VSV-G. Both pseudotypes have comparable physical titers, but infectious titers with the RRV pseudotype are lower than with VSV-G. Incorporation of SFV glycoproteins into lentivirus vector is less efficient, leading to decreased physical and infectious titers. The transduction rates with VSV-G-, RRV-, and SFV-pseudotyped lentivirus vectors into adherent cell lines can be significantly increased by using a combination of Polybrene and plates coated with CH-296 recombinant fibronectin fragments. Together, our data suggest that RRV and SFV glycoproteins might be suitable as alternatives to VSV-G for pseudotyping lentivirus vectors.
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PMID:Human immunodeficiency virus type 1-derived lentivirus vectors pseudotyped with envelope glycoproteins derived from Ross River virus and Semliki Forest virus. 1472 97

Enhancement of retroviral transduction efficiency has been achieved by several physical and chemical approaches. However, the application of those methods is hampered by not easily scalable configurations. In this study, instead of looking into the effect of sonoporation, the potential of ultrasonic standing wave fields (USWF) to facilitate retroviral transduction rate was explored. We reasoned that, driven by the primary acoustic radiation force, suspended cells moved to the pressure nodal planes first and formed cell bands. Nanometer-sized retroviruses, circulated between nodal planes by acoustic microstreaming, then used the preformed cell bands as the nucleating sites to attach on. As a result, the encounter opportunity between retroviruses and cells was increased and further facilitated the gene delivery efficiency. Our results showed that mega-Hertz USWF brought K562 erythroleukemia cells (10(6) cells/ml) and vesicular stomatitis virus G-protein (VSV-G) pseudotyped retroviruses (titer of 5 x 10(6) CFU/ml) into close contact at the pressure nodal planes, yielding a four-fold increment of enhanced green fluorescent protein transgene expression after 5-min USWF exposure in the presence of Polybrene. Furthermore, with a fixed titer of retrovirus, the transduction rate was augmented with the increase of cell concentration. In summary, USWF offer a feasible means to enhance retroviral transduction efficiency in large-scale settings.
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PMID:Enhanced retroviral gene delivery in ultrasonic standing wave fields. 1564 63

Lentiviral vectors (LVs) are attractive vehicles for the transduction of human dendritic cells (DCs) in order to mobilize their endogenous antigen presentation pathways. We analyzed here how to improve the efficiency of LV transduction, which we performed at the initial stages of the differentiation of purified monocytes into dendritic cells (Mo-DCs). Using LVs pseudotyped with the vesicular stomatitis virus envelope G glycoprotein (VSV-G), we found that a conditioned medium derived from dying monocytes (MCM) improved by 2- to 10- fold the proportion of transduced Mo-DCs. This enhanced transduction efficiency requires the presence of MCM during the initial stage of LV transduction and does not affect the phenotype and antigen presentation function of terminally differentiated Mo-DCs. Importantly, we found that MCM derived from a human acute monocytic leukemia cell line, THP-1, was equally effective. The MCM activity was heat stable (56 degrees C) and was present in the soluble fraction after high-speed centrifugation. Altogether our results show that a soluble factor present in dying monocyte cultures can replace advantageously facilitating agents such as Polybrene, to achieve high LV transductions levels. This protocol can be performed with autologous monocytes and is therefore applicable in clinical settings.
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PMID:Enhanced lentiviral transduction of monocyte-derived dendritic cells in the presence of conditioned medium from dying monocytes. 1732 25

Vesicular stomatitis virus (VSV) is a promising oncolytic virus (OV). Although VSV is effective against a majority of pancreatic ductal adenocarcinoma cell (PDAC) cell lines, some PDAC cell lines are highly resistant to VSV, and the mechanisms of resistance are still unclear. JAK1/2 inhibitors (such as ruxolitinib and JAK inhibitor I) strongly stimulate VSV replication and oncolysis in all resistant cell lines but only partially improve the susceptibility of resistant PDACs to VSV. VSV tumor tropism is generally dependent on the permissiveness of malignant cells to viral replication rather than on receptor specificity, with several ubiquitously expressed cell surface molecules playing a role in VSV attachment to host cells. However, as VSV attachment to PDAC cells has never been tested before, here we examined if it was possibly inhibited in resistant PDAC cells. Our data show a dramatically weaker attachment of VSV to HPAF-II cells, the most resistant human PDAC cell line. Although sequence analysis of low-density lipoprotein (LDL) receptor (LDLR) mRNA did not reveal any amino acid substitutions in this cell line, HPAF-II cells displayed the lowest level of LDLR expression and dramatically lower LDL uptake. Treatment of cells with various statins strongly increased LDLR expression levels but did not improve VSV attachment or LDL uptake in HPAF-II cells. However, LDLR-independent attachment of VSV to HPAF-II cells was dramatically improved by treating cells with Polybrene or DEAE-dextran. Moreover, combining VSV with ruxolitinib and Polybrene or DEAE-dextran successfully broke the resistance of HPAF-II cells to VSV by simultaneously improving VSV attachment and replication.IMPORTANCE Oncolytic virus (OV) therapy is an anticancer approach that uses viruses that selectively infect and kill cancer cells. This study focuses on oncolytic vesicular stomatitis virus (VSV) against pancreatic ductal adenocarcinoma (PDAC) cells. Although VSV is effective against most PDAC cells, some are highly resistant to VSV, and the mechanisms are still unclear. Here we examined if VSV attachment to cells was inhibited in resistant PDAC cells. Our data show very inefficient attachment of VSV to the most resistant human PDAC cell line, HPAF-II. However, VSV attachment to HPAF-II cells was dramatically improved by treating cells with polycations. Moreover, combining VSV with polycations and ruxolitinib (which inhibits antiviral signaling) successfully broke the resistance of HPAF-II cells to VSV by simultaneously improving VSV attachment and replication. We envision that this novel triple-combination approach could be used in the future to treat PDAC tumors that are highly resistant to OV therapy.
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PMID:Ruxolitinib and Polycation Combination Treatment Overcomes Multiple Mechanisms of Resistance of Pancreatic Cancer Cells to Oncolytic Vesicular Stomatitis Virus. 2856 76