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development of a murine mycobacterial growth inhibition assay for evaluating vaccines against mycobacterium tuberculosis.the development and characterization of new tuberculosis (tb) vaccines has been impeded by the lack of reproducible and reliable in vitro assays for measuring vaccine activity. in this study, we developed a murine in vitro mycobacterial growth inhibition assay for evaluating tb vaccines that directly assesses the capacity of immune splenocytes to control the growth of mycobacterium tuberculosis within infected macrophages. using this in vitro assay, protective immune responses induced by immuniz ...200919458207
strong ability of nef-specific cd4+ cytotoxic t cells to suppress human immunodeficiency virus type 1 (hiv-1) replication in hiv-1-infected cd4+ t cells and macrophages.a restricted number of studies have shown that human immunodeficiency virus type 1 (hiv-1)-specific cytotoxic cd4+ t cells are present in hiv-1-infected individuals. however, the roles of this type of cd4+ t cell in the immune responses against an hiv-1 infection remain unclear. in this study, we identified novel nef epitope-specific hla-drb1*0803-restricted cytotoxic cd4+ t cells. the cd4+ t-cell clones specific for nef187-203 showed strong gamma interferon production after having been stimulat ...200919457989
hypercostimulation through 4-1bb distorts homeostasis of immune cells.the deleterious side effects associated with a recent clinical trial with anti-cd28 superagonist abs have questioned the use of reagents to costimulatory molecules in human therapy. we now show that sustained signaling from an agonist ab to 4-1bb, a member of the tnfr superfamily, results in detrimental effects on immune cell homeostasis. repeated anti-4-1bb treatment during the reconstitution of hematopoietic cells in irradiated mice engrafted with bone marrow, or in mice infected with vaccinia ...200919454670
proteomic screening of variola virus reveals a unique nf-kappab inhibitor that is highly conserved among pathogenic orthopoxviruses.identification of the binary interactions between viral and host proteins has become a valuable tool for investigating viral tropism and pathogenesis. here, we present the first systematic protein interaction screening of the unique variola virus proteome by using yeast 2-hybrid screening against a variety of human cdna libraries. several protein-protein interactions were identified, including an interaction between variola g1r, an ankryin/f-box containing protein, and human nuclear factor kappa ...200919451633
recombinant modified vaccinia ankara (mva) effectively boosts dna-primed hiv-specific immune responses in humans despite pre-existing vaccinia immunity.the presence of vector-specific immune responses may hamper the induction of responses to a foreign antigen encoded by the vector. we evaluated the impact of pre-existing immunity to vaccinia virus on the induction of hiv-specific responses after immunization of healthy volunteers with a hiv-1 dna prime-mva boost vaccine. following three priming immunizations with hiv-1 dna plasmids, the volunteers were boosted with a single injection of recombinant mva encoding hiv-1 proteins. pre-existing immu ...200919450644
harnessing the unique local immunostimulatory properties of modified vaccinia ankara (mva) virus to generate superior tumor-specific immune responses and antitumor activity in a diversified prime and boost vaccine regimen.recombinant poxviruses expressing tumor-associated antigens (taas) are currently being evaluated in clinical trials as an approach to treat various cancers. we have previously generated poxviral vectors expressing a taa and a triad of costimulatory molecules (b7-1, icam-1, and lfa-3; tricom) as transgenes, including replication competent recombinant vaccinia (rv) or replication-defective modified vaccinia ankara (mva), to prime tumor-specific immune responses, and a replication-defective recombi ...200919450631
polymerase translocation with respect to single-stranded nucleic acid: looping or wrapping of primer around a poly(a) polymerase.vaccinia virus protein vp55 translocates continuously with respect to single-stranded nucleic acid while extending its 3'end. here, all key sites of polymerase-primer interaction were identified, demonstrating the wrapping or looping of polyadenylation primer around the polymerase during translocation. side-chain substitutions at one of the sites indicated its requirement for tail extension beyond approximately 12 nucleotides in length, and conformational changes observed upon oligonucleotide bi ...200919446524
the proteoglycan bamacan is a host cellular ligand of vaccinia virus neurovirulence factor n1l.neurovirulence is one of the pathological complications associated with vaccinia virus (vv) infection/vaccination. although the viral n1l protein has been identified as the neurovirulence factor, none of the host n1l-interacting factors have been identified so far. in the present study, we identified n1l-interacting proteins by screening a human brain cdna expression library with n1l as a bait protein in a yeast two-hybrid analysis. the analysis revealed that n1l interacts with human brain-origi ...200919444697
effective expression of recombinant cytotoxic protein via its attachment to a polyglutamine domain.inadvertent cytotoxicity may hinder the expression of many recombinant proteins that are of industrial or medicinal importance. here, we show that covalent binding of the influenza a cytotoxic protein m2 to a polyglutamine domain (polyq-m2; qm2) results in significant delay of its cytotoxic effects when compared to wild-type protein (m2wt). we also show that while expression of recombinant m2wt from a/wsn/1933 strain could not be attained in vaccinia virus (vv), polyq-m2 was successfully express ...200919441878
b7-h1 blockade increases survival of dysfunctional cd8(+) t cells and confers protection against leishmania donovani infections.experimental visceral leishmaniasis (vl) represents an exquisite model to study cd8(+) t cell responses in a context of chronic inflammation and antigen persistence, since it is characterized by chronic infection in the spleen and cd8(+) t cells are required for the development of protective immunity. however, antigen-specific cd8(+) t cell responses in vl have so far not been studied, due to the absence of any defined leishmania-specific cd8(+) t cell epitopes. in this study, transgenic leishma ...200919436710
in vitro host range, multiplication and virion forms of recombinant viruses obtained from co-infection in vitro with a vaccinia-vectored influenza vaccine and a naturally occurring cowpox virus isolate.poxvirus-vectored vaccines against infectious diseases and cancer are currently under development. we hypothesized that the extensive use of poxvirus-vectored vaccine in future might result in co-infection and recombination between the vaccine virus and naturally occurring poxviruses, resulting in hybrid viruses with unpredictable characteristics. previously, we confirmed that co-infecting in vitro a modified vaccinia virus ankara (mva) strain engineered to express influenza virus haemagglutinin ...200919435511
listeria monocytogenes delivery of hpv-16 major capsid protein l1 induces systemic and mucosal cell-mediated cd4+ and cd8+ t-cell responses after oral immunization.neutralizing antibodies are thought to be required at mucosal surfaces to prevent human papillomavirus (hpv) transmission. however, the potential for cell-mediated immunity in mediating protection against hpv infection has not been well explored. we generated recombinant listeria monocytogenes (lm) constructs that secrete listeriolysin o (llo) fused with overlapping n-terminal (llo-l1(1-258)) or c-terminal (llo-l1(238-474)) fragments of hpv type 16 major capsid protein l1 (hpv-16-l1). oral immun ...200919435416
role of cell signaling in poxvirus-mediated foreign gene expression in mammalian cells.poxviruses have been extensively used as a promising vehicle to efficiently deliver a variety of antigens in mammalian hosts to induce immune responses against infectious diseases and cancer. using recombinant vaccinia virus (vv) and canarypox virus (alvac) expressing enhanced green fluorescent protein (egfp) or multiple hiv-1 gene products, we studied the role of four cellular signaling pathways, the phosphoinositide-3-oh kinase (pi3k), extracellular signal-regulated kinase (erk), p38 mitogen-a ...200919428911
inhibition of vaccinia virus replication by peptide aptamers.a20 protein is a major component of the vaccinia virus replication complex. it binds to the dna polymerase e9, the uracil dna glycosylase d4 and the primase/helicase d5, three proteins that are essential for viral dna synthesis. the identification of molecules able to interact with the replication complex and inhibit its activity is a promising strategy for the design of new anti-orthopoxvirus drugs. in this study, we used a yeast genetic approach to select, from combinatorial libraries, 8-mers ...200919428604
vaccinia virus strain differences in cell attachment and entry.vaccinia virus (vacv) strain wr can enter cells by a low ph endosomal pathway or direct fusion with the plasma membrane at neutral ph. here, we compared attachment and entry of five vacv strains in six cell lines and discovered two major patterns. only wr exhibited ph 5-enhanced rate of entry following neutral ph adsorption to cells, which correlated with sensitivity to bafilomycin a1, an inhibitor of endosomal acidification. entry of ihd-j, copenhagen and elstree strains were neither accelerate ...200919428041
increased per cell ifn-gamma productivity indicates recent in vivo activation of t cells.immunization with vaccinia virus causes long-term immunity. efforts have been made to characterize the t cells responsible for this protection. recently, t cell subsets were described that not only co-express multiple cytokines, but also show increased per cell cytokine productivity. these highly productive cells are often considered to be the most protective. we used elispot assays to measure per cell ifn-gamma productivity of vaccinia-specific t cells in childhood immunized adults immediately ...200919427634
phylogenetic analysis of three genes of penguinpox virus corresponding to vaccinia virus g8r (vltf-1), a3l (p4b) and h3l reveals that it is most closely related to turkeypox virus, ostrichpox virus and pigeonpox virus.phylogenetic analysis of three genes of penguinpox virus, a novel avipoxvirus isolated from african penguins, reveals its relationship to other poxviruses. the genes corresponding to vaccinia virus g8r (vltf-1), a3l (p4b) and h3l were sequenced and phylogenetic trees (neighbour-joining and upgma) constructed from muscle nucleotide and amino acid alignments of the equivalent sequences from several different poxviruses. based on this analysis, pepv was confirmed to belong to the genus avipoxvirus, ...200919426497
hiv escape from natural killer cytotoxicity: nef inhibits nkp44l expression on cd4+ t cells.hiv infection induces a progressive depletion of cd4 t cells. we showed that nkp44l, a cellular ligand for an activating natural killer (nk) receptor, is expressed on cd4 t cells during hiv infection and is correlated with both cd4 cell depletion and increase in viral load. nkp44lcd4 t cells are highly sensitive to the nk lysis activity. in contrast, hiv-infected cd4 t cells are resistant to nk killing, suggesting that hiv-1 developed strategies to avoid detection by the host cell immunity.200919424050
vaccinia virus g8r protein: a structural ortholog of proliferating cell nuclear antigen (pcna).eukaryotic dna replication involves the synthesis of both a dna leading and lagging strand, the latter requiring several additional proteins including flap endonuclease (fen-1) and proliferating cell nuclear antigen (pcna) in order to remove rna primers used in the synthesis of okazaki fragments. poxviruses are complex viruses (dsdna genomes) that infect eukaryotes, but surprisingly little is known about the process of dna replication. given our previous results that the vaccinia virus (vacv) g5 ...200919421403
expanding the repertoire of modified vaccinia ankara-based vaccine vectors via genetic complementation strategies.modified vaccinia virus ankara (mva) is a safe, highly attenuated orthopoxvirus that is being developed as a recombinant vaccine vector for immunization against a number of infectious diseases and cancers. however, the expression by mva vectors of large numbers of poxvirus antigens, which display immunodominance over vectored antigens-of-interest for the priming of t cell responses, and the induction of vector-neutralizing antibodies, which curtail the efficacy of subsequent booster immunization ...200919421328
elucidating and minimizing the loss by recombinant vaccinia virus of human immunodeficiency virus gene expression resulting from spontaneous mutations and positive selection.while characterizing modified vaccinia virus recombinants (rmvas) containing human immunodeficiency virus env and gag-pol genes, we detected nonexpressing mutants by immunostaining individual plaques. in many cases, the numbers of mutants increased during successive passages, indicating strong selection pressure. this phenomenon provided an opportunity to investigate the formation of spontaneous mutations in vaccinia virus, which encodes its own cytoplasmic replication system, and a challenge to ...200919420086
synthesis and antiviral activity of new pyrazole and thiazole derivatives.new n-acetyl (5-8) and n-thiocarbamoyl (9-12) derivatives of 4,5-dihydropyrazole were synthesized starting from alpha,beta-unsaturated ketones under the effect of hydrazine hydrate and thiosemicarbazide, respectively. n-thiocarbamoylpyrazole derivatives (9-12) were cyclized using either ethyl bromoacetate or phenacyl bromides to afford the novel pyrazolothiazol-4(5h)-ones (13-16) or pyrazolothiazoles (17-24). the antiviral activity for such novel compounds against a broad panel of viruses in dif ...200919419804
the adaptor molecule myd88 directly promotes cd8 t cell responses to vaccinia virus.vaccinia virus (vacv) elicits a robust cd8 t cell response that plays an important role in host resistance. to date, there is little information on the molecules that are essential to generate large pools of vacv-specific effector cd8 t cells. in this study, we show that the adaptor molecule myd88 is critical for the magnitude of primary cd8 t cell responses to both dominant and subdominant vacv epitopes. myd88(-/-) mice exhibit profound reduction in cd8 t cell expansion and antiviral cytokine p ...200919414781
differential diagnosis of orf viruses by a single-step pcr.the complete nucleotide sequence of the a32l gene (named after vaccinia virus, corresponding with open reading frame 108 of the orf virus and encoding an atpase) of the orf virus was studied using samples of orf virus from infected goats, which were collected from six outbreaks in central taiwan. dna sequence analysis of the a32l genes of these and isolates from other countries showed sequence heterogeneity (base pair variation and deletion) in the 3'-terminal regions. this finding led to the de ...200919409929
murine norovirus infection has no significant effect on adaptive immunity to vaccinia virus or influenza a virus.murine norovirus (mnv) is endemic in many research mouse colonies. although mnv infections are typically asymptomatic in immunocompetent mice, the effects of mnv infection on subsequent experimental viral infections are poorly documented. here, we infected c57bl/6 mice with mnv and then with either vaccinia virus or influenza a virus. mnv infection had no effect on cd8(+) t-cell or antibody responses to secondary viruses or to secondary virus-induced morbidity or mortality. while our findings su ...200919403665
vaccinia virus p37 interacts with host proteins associated with le-derived transport vesicle biogenesis.proteins associated with the late endosome (le) appear to play a central role in the envelopment of a number of taxonomically diverse viruses. how viral proteins interact with le-associated proteins to facilitate envelopment is not well understood. le-derived transport vesicles form through the interaction of rab9 gtpase with cargo proteins, and tip47, a rab9-specific effector protein. vaccinia virus (vv) induces a wrapping complex derived from intracellular host membranes to envelope intracellu ...200919400954
alkoxyalkyl esters of 9-(s)-(3-hydroxy-2-phosphonomethoxypropyl) adenine are potent and selective inhibitors of hepatitis b virus (hbv) replication in vitro and in hbv transgenic mice in vivo.alkoxyalkyl esters of acyclic nucleoside phosphonates have previously been shown to have increased antiviral activity when they are administered orally in animal models of viral diseases, including lethal infections with vaccinia virus, cowpox virus, ectromelia virus, murine cytomegalovirus, and adenovirus. 9-(s)-(3-hydroxy-2-phosphonomethoxypropyl)adenine [(s)-hpmpa] was previously shown to have activity against hepatitis b virus (hbv) in vitro. to assess the effect of alkoxyalkyl esterificatio ...200919398648
development of a 1-step cell-based assay for cost-effective screening of antiviral drugs for vaccinia virus.we report a 1-step assay to screen antiviral substances combining the simultaneous application of cells, virus sample, and drug to 96-well plates. the results were obtained within 26 h when vaccinia virus plaques were counted or virus-induced cytopathic effect was measured. this fast cost-effective procedure may be used for other cytopathic viruses and is suitable to 1st screening tests.200919395220
inhibition of vaccinia virus entry by a broad spectrum antiviral peptide.concerns about the possible use of variola virus, the causative agent of smallpox, as a weapon for bioterrorism have led to renewed efforts to identify new antivirals against orthopoxviruses. we identified a peptide, eb, which inhibited infection by vaccinia virus with an ec(50) of 15 microm. a control peptide, ebx, identical in composition to eb but differing in sequence, was inactive (ec50>200 microm), indicating sequence specificity. the inhibition was reversed upon removal of the peptide, an ...200919395056
unwinding by local strand separation is critical for the function of dead-box proteins as rna chaperones.the dead-box proteins cyt-19 in neurospora crassa and mss116p in saccharomyces cerevisiae are broadly acting rna chaperones that function in mitochondria to stimulate group i and group ii intron splicing and to activate mrna translation. previous studies showed that the s. cerevisiae cytosolic/nuclear dead-box protein ded1p could stimulate group ii intron splicing in vitro. here, we show that ded1p complements mitochondrial translation and group i and group ii intron splicing defects in mss116de ...200919393667
vaccinia-induced epidermal growth factor receptor-mek signalling and the anti-apoptotic protein f1l synergize to suppress cell death during infection.f1l is a functional bcl-2 homologue that inhibits apoptosis at the mitochondria during vaccinia infection. however, the extent and timing of cell death during deltaf1l virus infection suggest that additional viral effectors cooperate with f1l to limit apoptosis. here we report that vaccinia growth factor (vgf), a secreted virulence factor, promotes cell survival independently of its role in virus multiplication. analysis of single and double knockout viruses reveals that vgf acts synergistically ...200919388902
activation of the pi3k/akt pathway early during vaccinia and cowpox virus infections is required for both host survival and viral replication.viral manipulation of the transduction pathways associated with key cellular functions such as actin remodeling, microtubule stabilization, and survival may favor a productive viral infection. here we show that consistent with the vaccinia virus (vacv) and cowpox virus (cpxv) requirement for cytoskeleton alterations early during the infection cycle, pbk/akt was phosphorylated at s473 [akt(s473-p)], a modification associated with the mammalian target of rapamycin complex 2 (mtorc2), which was par ...200919386722
selection of appropriate serological tests to measure the incidence of natural leishmania infantum infection during dna/mva prime/boost canine vaccine trials.in response to the increasing need for field trials of experimental dna vaccines against zoonotic visceral leishmaniasis in dogs, our aim was to validate the use of elisa protocols which will be suitable for detection of natural infection in vaccinated dogs. we have previously demonstrated that dna/modified vaccinia virus ankara (mva) vaccine expressing tryparedoxin peroxidase (tryp) induced high titres of tryp antigen-specific igg in immunized dogs. here we report our findings that seroconversi ...200919386420
poxvirus tropism for primary human leukocytes and hematopoietic cells.poxviruses including canarypox (alvac) and vaccinia viruses have, in recent years, received considerable attention as live vectors for the development of vaccines against infectious diseases such as aids, malaria, and tuberculosis. however, the cellular targets for viral infection within the human immune system and the consequences of infection for cells involved in the generation of immune responses have not been clearly delineated. using recombinant enhanced green fluorescence protein (egfp)-e ...200919378122
discerning regulation of cis- and trans-presentation of cd8+ t-cell epitopes by ebv-encoded oncogene lmp-1 through self-aggregation.activation of the nuclear factor-kappab pathway by epstein-barr virus-encoded latent membrane protein-1 (lmp-1) leads to an up-regulation of the major histocompatibility complex class i antigen-processing pathway. paradoxically, lmp-1 itself induces a subdominant cd8+ t-cell response and appears to have evolved to avoid immune recognition. here we show that, although expression of lmp-1 in human cells dramatically enhanced the trans-presentation of cd8+ t-cell epitopes, cis-presentation of lmp-1 ...200919372256
vaccinia virus e3 suppresses expression of diverse cytokines through inhibition of the pkr, nf-kappab, and irf3 pathways.the vaccinia virus double-stranded rna binding protein e3 has been demonstrated to inhibit the expression of cytokines, including beta interferon (ifn-beta) and tumor necrosis factor alpha (tnf-alpha). however, few details regarding the molecular mechanisms of this inhibition have been described. using real-time pcr arrays, we found that e3 suppressed the induction of a diverse array of cytokines representing members of the ifn, interleukin (il), tnf, and transforming growth factor cytokine fami ...200919369349
disulfide bond formation at the c termini of vaccinia virus a26 and a27 proteins does not require viral redox enzymes and suppresses glycosaminoglycan-mediated cell fusion.vaccinia virus a26 protein is an envelope protein of the intracellular mature virus (imv) of vaccinia virus. a mutant a26 protein with a truncation of the 74 c-terminal amino acids was expressed in infected cells but failed to be incorporated into imv (w. l. chiu, c. l. lin, m. h. yang, d. l. tzou, and w. chang, j. virol 81:2149-2157, 2007). here, we demonstrate that a27 protein formed a protein complex with the full-length form but not with the truncated form of a26 protein in infected cells as ...200919369327
viral load and clinical disease enhancement associated with a lentivirus cytotoxic t lymphocyte vaccine regimen.effective dna-based vaccines against lentiviruses will likely induce ctl against conserved viral proteins. equine infectious anemia virus (eiav) infects horses worldwide, and serves as a useful model for lentiviral immune control. although attenuated live eiav vaccines have induced protective immune responses, dna-based vaccines have not. in particular, dna-based vaccines have had limited success in inducing ctl responses against intracellular pathogens in the horse. we hypothesized that priming ...200919368787
mva.85a boosting of bcg and an attenuated, phop deficient m. tuberculosis vaccine both show protective efficacy against tuberculosis in rhesus macaques.continuous high global tuberculosis (tb) mortality rates and variable vaccine efficacy of mycobacterium bovis bacille calmette-guérin (bcg) motivate the search for better vaccine regimes. relevant models are required to downselect the most promising vaccines entering clinical efficacy testing and to identify correlates of protection.200919367339
vaccinia virus infection & temporal analysis of virus gene expression: part 3.the family poxviridae consists of large double-stranded dna containing viruses that replicate exclusively in the cytoplasm of infected cells. members of the orthopox genus include variola, the causative agent of human small pox, monkeypox, and vaccinia (vac), the prototypic member of the virus family. within the relatively large (approximately 200 kb) vaccinia genome, three classes of genes are encoded: early, intermediate, and late. while all three classes are transcribed by virally-encoded rna ...200919365326
vulvar vaccinia infection after sexual contact with a smallpox vaccinee.vaccinia (smallpox) vaccine is an effective immunizing agent that brought about global eradication of naturally occurring smallpox, as declared by the world health organization in 1980. the united states ceased generalized smallpox vaccination in 1972 but reinstated it in 2002 for military personnel and selected healthcare workers (first responders who may be investigating possible cases of smallpox or caring for patients in selected hospitals) after the 2001 bioterrorism attacks. since reinstit ...200919365178
vaccinia virus infection & temporal analysis of virus gene expression: part 2.the family poxviridae consists of large double-stranded dna containing viruses that replicate exclusively in the cytoplasm of infected cells. members of the orthopox genus include variola, the causative agent of human small pox, monkeypox, and vaccinia (vac), the prototypic member of the virus family. within the relatively large (approximately 200 kb) vaccinia genome, three classes of genes are encoded: early, intermediate, and late. while all three classes are transcribed by virally-encoded rna ...200919363464
the expression of the soluble isoform of hflt3 ligand by recombinant vaccinia virus enhances immunogenicity of the vector.recombinant vaccinia viruses (rvacv) expressing various tumor-associated antigens have been shown to elicit anti-tumor effect in numerous experimental models and clinical trials. we tested the hypotheses that rvacv expressing biologically active fms-like tyrosine kinase 3 ligand (flt3l) would show higher immunogenicity than control viruses expressing only model antigen and that coexpression of flt3l would influence anti-tumor activity of rvacv in the preventive and therapeutic arrangements of th ...200919360312
the orthopoxvirus 68-kilodalton ankyrin-like protein is essential for dna replication and complete gene expression of modified vaccinia virus ankara in nonpermissive human and murine cells.modified vaccinia virus ankara (mva) is a highly attenuated and replication-deficient vaccinia virus (vacv) that is being evaluated as replacement smallpox vaccine and candidate viral vector. mva lacks many genes associated with virulence and/or regulation of virus tropism. the 68-kda ankyrin-like protein (68k-ank) is the only ankyrin repeat-containing protein that is encoded by the mva genome and is highly conserved throughout the orthopoxvirus genus. we showed previously that 68k-ank is compos ...200919357172
a multi-valent vaccinia virus-based tuberculosis vaccine molecularly adjuvanted with interleukin-15 induces robust immune responses in mice.tuberculosis caused by mycobacterium tuberculosis is responsible for nearly two million deaths every year globally. a single licensed vaccine derived from mycobacterium bovis, bacille calmette-guerin (bcg) administered perinatally as a prophylactic vaccine has been in use for over 80 years and confers substantial protection against childhood tuberculous meningitis and miliary tuberculosis. however, the bcg vaccine is virtually ineffective against the adult pulmonary form of tuberculosis that is ...200919356615
a recombinant dna and vaccinia virus prime-boost regimen induces potent long-term t-cell responses to hcv in balb/c mice.to explore the best prime-boost regimen and evaluate the t-cellular response memory against hcv, we constructed two dna vaccine candidates (pvrc-ce1e2 and paav-ce1e2) and two recombinant viruses (rttv-e1e2 and raav-e1e2) and then assessed the immune response to different prime-boost patterns in balb/c mice. the rttv-e1e2 boosted the immune response to hcv dna vaccine prime significantly, and the inverted terminal repeat sequence harboring dna construct paav-ce1e2 was the best prime agent in this ...200919356609
efficacy of systemically administered oncolytic vaccinia virotherapy for malignant gliomas is enhanced by combination therapy with rapamycin or cyclophosphamide.the oncolytic effects of a systemically delivered, replicating, double-deleted vaccinia virus has been previously shown for the treatment of many cancers, including colon, ovarian, and others. the purpose of this study was to investigate the oncolytic potential of double-deleted vaccinia virus alone or in combination with rapamycin or cyclophosphamide to treat malignant gliomas in vitro and in vivo.200919351762
candidate influenza vaccines based on recombinant modified vaccinia virus ankara.recombinant modified vaccinia virus ankara (mva) is attractive and promising as a novel viral vector for the expression of foreign genes of interest because it possesses unique properties. in particular, its excellent safety profile and the availability of versatile vector technologies have frequently made mva the vaccinia virus of choice for preclinical and clinical studies. owing to its avirulence and deficiency to productively replicate after in vivo inoculation, mva can be used under biosafe ...200919348560
vaccination of patients with metastatic renal cancer with modified vaccinia ankara encoding the tumor antigen 5t4 (trovax) given alongside interferon-alpha.approximately 90% of renal cell tumors overexpress the tumor antigen 5t4. the attenuated strain of vaccinia virus, modified vaccinia ankara, has been engineered to express 5t4 (trovax). we conducted an open-label phase 1/2 trial in which trovax was administered alongside interferon-alpha (ifnalpha) to 11 patients with metastatic renal cell carcinoma. antigen-specific cellular and humoral responses were monitored throughout the study, and clinical responses were assessed by measuring the changes ...200919342962
a single-chain h-2db molecule presenting an influenza virus nucleoprotein epitope shows enhanced ability at stimulating cd8+ t cell responses in vivo.we have generated a construct encoding a single-chain h-2d(b) mouse mhc class i molecule in which an influenza virus nucleoprotein (np) epitope, amino acid sequence asnenmdam, is fused to mouse beta(2)-microglobulin and the d(b) h chain via flexible linker sequences. this single-chain trimer (sct) was efficiently expressed at the cell surface independently of tap and endogenous beta(2)-microglobulin, and it was recognized directly and efficiently by specific t cells in vitro. a recombinant vacci ...200919342630
evaluation of smallpox vaccines using variola neutralization.the search for a 'third'-generation smallpox vaccine has resulted in the development and characterization of several vaccine candidates. a significant barrier to acceptance is the absence of challenge models showing induction of correlates of protective immunity against variola virus. in this light, virus neutralization provides one of few experimental methods to show specific 'in vitro' activity of vaccines against variola virus. here, we provide characterization of the ability of a modified va ...200919339477
emerging biological functions of the vaccinia-related kinase (vrk) family.the vaccinia-related kinases (vrks) branched off early from the family of casein kinase (ck) i and compose a relatively uncharacterized family of the kinome. the vrks were discovered due to their close sequence relation to the vaccinia virus b1r serine/threonine kinase. they were first described in phosphorylation of transcription factors that led to the discovery of an autoregulatory mechanism between vrk and the tumor suppressor transcription factor p53. the relevance of vrks has broadened rec ...200919337973
chimeric calicivirus-like particles elicit protective anti-viral cytotoxic responses without adjuvant.we have analyzed the potential of virus-like particles (vlps) from rabbit hemorrhagic disease virus (rhdv) as a delivery system for foreign t cell epitopes. to accomplish this goal, we generated chimeric rhdv-vlps incorporating a cd8(+) t cell epitope (siinfekl) derived from chicken ovalbumin (ova). the ova epitope was inserted in the capsid protein (vp60) of rhdv at two different locations: 1) the n-terminus, predicted to be facing to the inner core of the vlps, and 2) a novel insertion site pr ...200919327809
a replicon trans-packaging system reveals the requirement of nonstructural proteins for the assembly of bovine viral diarrhea virus (bvdv) virion.a selective trans-packaging system was developed to produce and isolate bovine viral diarrhea virus (bvdv) pseudo-particles with complementing reporter replicons and their packaging proteins expressed in trans with recombinant vaccinia virus. the encapsidation of replicon rns3-5b was dependent not only on the in trans expression of structural proteins c, e(rns), e1 and e2, but also the nonstructural proteins, p7 and contiguous precursor ns2-3-4a. nonstructural p7, ns4b, ns5a or ns5b could be exp ...200919327808
prime-boost vaccination using recombinant mycobacterium bovis bcg and recombinant vaccinia virus dis harboring hiv-1 crf01_ae gag in mice: influence of immunization routes.we have previously reported that live vector-based hiv-1 gag vaccine candidate using bcg as a vector was achievable in balb/c mice. although the gag-specific ctl induced by this live candidate vaccine is significantly high, persistence of ctl remains unclear. thus, efforts were made to explore the potential of recombinant vaccinia virus dis strain harboring the same hiv-1 crf01_ae gag gene (rvaccinia/ hiv-1gage) present in the bcg construct, using different immunization routes. after one month f ...200919323012
improved survival in rhesus macaques immunized with modified vaccinia virus ankara recombinants expressing simian immunodeficiency virus envelope correlates with reduction in memory cd4+ t-cell loss and higher titers of neutralizing antibody.previous studies demonstrated that immunization of macaques with simian immunodeficiency virus (siv) gag-pol and env recombinants of the attenuated poxvirus modified vaccinia virus ankara (mva) provided protection from high viremia and aids following challenge with a pathogenic strain of siv. although all animals became infected, plasma viremia was significantly reduced in animals that received the mva-siv recombinant vaccines compared with animals that received nonrecombinant mva. most importan ...200919321617
protein kinase pkr-dependent activation of mitogen-activated protein kinases occurs through mitochondrial adapter ips-1 and is antagonized by vaccinia virus e3l.the p38 and c-jun n-terminal kinase (jnk) mitogen-activated protein kinases (mapks) play important roles in the host innate immune response. the protein kinase regulated by rna (pkr) is implicated in p38 mapk activation in response to proinflammatory signals in mouse embryonic fibroblasts. to test the role of pkr in the activation of p38 and jnk mapks in human cells following viral infection, hela cells made stably deficient in pkr by using an rna interference strategy were compared to cells wit ...200919321614
a functional type i topoisomerase from pseudomonas aeruginosa.pseudomonas aeruginosa encodes a putative topoisomerase with sequence similarity to the eukaryotic type ib topoisomerase from vaccinia virus. residues in the active site are conserved, notably tyr292 which would be predicted to form the transient covalent bond to dna.200919317906
inhibition of vaccinia virus replication by two small interfering rnas targeting b1r and g7l genes and their synergistic combination with cidofovir.in view of the threat of the potential use of variola virus in a terrorist attack, considerable efforts have been performed to develop new antiviral strategies against orthopoxviruses. here we report on the use of rna interference, either alone or in combination with cidofovir, as an approach to inhibit orthopoxvirus replication. two selected small interfering rnas (sirnas), named sib1r-2 and sig7l-1, and a previously reported sirna, i.e., sid5r-2 (which targets the viral d5r mrna), were evaluat ...200919307376
recall responses by helpless memory cd8+ t cells are restricted by the up-regulation of pd-1.cd4 help is crucial for memory cd8(+) t cell development, yet the mechanisms of cd4 help and why (cd4) helpless memory cd8(+) t cells elicit poor recall responses are currently not well understood. in this study we investigated these questions using an in vivo acute virus infection model. we show herein that cd4 help during priming is required for memory cd8(+) t cell differentiation, and that stimulation of cd40 during priming rescues the helpless defects in the absence of cd4(+) t cells. the d ...200919299723
downregulation of vaccinia virus intermediate and late promoters by host transcription factor yy1.approximately half of the intermediate and late gene transcriptional promoters of vaccinia virus have a binding site for the cellular transcription factor yy1 that overlaps the initiator elements. depletion of yy1 using rna interference enhanced the activity of these promoters, while overexpression of yy1 repressed their activity. viral promoter nucleotide replacements that specifically impair the binding of yy1 mostly alleviated the transcriptional repression and correlated with the ability of ...200919297611
a novel recombinant vaccinia virus expressing the human norepinephrine transporter retains oncolytic potential and facilitates deep-tissue imaging.noninvasive and repetitive monitoring of a virus in target tissues and/or specific organs of the body is highly desirable for the development of safe and efficient cancer virotherapeutics. we have previously shown that the oncolytic vaccinia virus glv-1h68 can target and eradicate human tumors in mice and that its therapeutic effects can be monitored by using optical imaging. here, we report on the development of a derivative of glv-1h68, a novel recombinant vaccinia virus (vacv) glv-1h99, which ...200919287510
nonreplicating vaccinia virus vectors expressing the h5 influenza virus hemagglutinin produced in modified vero cells induce robust protection.the timely development of safe and effective vaccines against avian influenza virus of the h5n1 subtype will be of the utmost importance in the event of a pandemic. our aim was first to develop a safe live vaccine which induces both humoral and cell-mediated immune responses against human h5n1 influenza viruses and second, since the supply of embryonated eggs for traditional influenza vaccine production may be endangered in a pandemic, an egg-independent production procedure based on a permanent ...200919279103
clinical and immunological response to attenuated tissue-cultured smallpox vaccine lc16m8.the attenuated, tissue-cultured, third-generation smallpox vaccine lc16m8 was administered to vaccinia-naive infants in japan during the 1970s without serious adverse events. it is a good candidate for use as part of a prevention plan for bioterrorism.200919278946
the antitumor and immunoadjuvant effects of ifn-alpha in combination with recombinant poxvirus vaccines.ifn-alpha is a pleiotropic cytokine possessing immunomodulatory properties that may improve the efficacy of therapeutic cancer vaccines. the aim of this study was to evaluate the effectiveness and compatibility of combining recombinant ifn-alpha with poxvirus vaccines targeting the human carcinoembryonic antigen (cea) in murine models of colorectal and pancreatic adenocarcinomas, where cea is a self-antigen.200919276249
highlights from the march 2009 issue of dna and cell biology. 200919267580
increased detection of proliferating, polyfunctional, hiv-1-specific t cells in dna-modified vaccinia virus ankara-vaccinated human volunteers by cultured ifn-gamma elispot assay.induction of a long-term immunological memory, which can expand and defend the host upon pathogen encounter, is the "holy grail" of vaccinology. here, using a sensitive cultured ifn-gamma elispot assay, we show that 50% (15 out of 30) of healthy, hiv-1/2-uninfected volunteers who received pthr.hiva dna prime-modified vaccinia virus ankara. hiva boost vaccine regimen 1 to 3 1/2 years ago had detectable hiv-1-specific t-cell responses. these t cells, predominantly of the cd4(+) subtype, could prol ...200919266489
contribution of nonneutralizing vaccine-elicited antibody activities to improved protective efficacy in rhesus macaques immunized with tat/env compared with multigenic vaccines.previously, chronic-phase protection against shiv(89.6p) challenge was significantly greater in macaques primed with replicating adenovirus type 5 host range mutant (ad5hr) recombinants encoding hivtat and env and boosted with tat and env protein compared with macaques primed with multigenic adenovirus recombinants (hivtat, hivenv, sivgag, sivnef) and boosted with tat, env, and nef proteins. the greater protection was correlated with tat- and env-binding abs. because the macaques lacked shiv(89. ...200919265150
acidic residues in the membrane-proximal stalk region of vaccinia virus protein b5 are required for glycosaminoglycan-mediated disruption of the extracellular enveloped virus outer membrane.the extracellular enveloped virus (eev) form of vaccinia virus (vacv) is surrounded by two lipid envelopes. this presents a topological problem for virus entry into cells, because a classical fusion event would only release a virion surrounded by a single envelope into the cell. recently, we described a mechanism in which the eev outer membrane is disrupted following interaction with glycosaminoglycans (gags) on the cell surface and thus allowing fusion of the inner membrane with the plasma memb ...200919264647
smallpox virus plaque phenotypes: genetic, geographical and case fatality relationships.smallpox (infection with orthopoxvirus variola) remains a feared illness more than 25 years after its eradication. historically, case-fatality rates (cfrs) varied between outbreaks (<1 to approximately 40 %), the reasons for which are incompletely understood. the extracellular enveloped virus (eev) form of orthopoxvirus progeny is hypothesized to disseminate infection. investigations with the closely related orthopoxvirus vaccinia have associated increased comet formation (eev production) with i ...200919264626
the rate of n-wasp exchange limits the extent of arp2/3-complex-dependent actin-based motility.understanding cell motility will require detailed knowledge not only of the localization of signalling networks regulating actin polymerization, but also of their dynamics. unfortunately, many signalling networks are not amenable to such analysis, as they are frequently transient and dispersed. by contrast, the signalling pathways used by pathogens undergoing actin-based motility are highly localized and operate in a constitutive fashion. taking advantage of this, we have analysed the dynamics o ...200919262673
engineering the vaccinia virus l1 protein for increased neutralizing antibody response after dna immunization.the licensed smallpox vaccine, comprised of infectious vaccinia virus, has associated adverse effects, particularly for immunocompromised individuals. therefore, safer dna and protein vaccines are being investigated. the l1 protein, a component of the mature virion membrane that is conserved in all sequenced poxviruses, is required for vaccinia virus entry into host cells and is a target for neutralizing antibody. when expressed by vaccinia virus, the unglycosylated, myristoylated l1 protein att ...200919257896
preparation of recombinant viral glycoproteins for novel and therapeutic antibody discovery.neutralizing antibodies are a critical component in the protection or recovery from viral infections. in the absence of available vaccines or antiviral drugs for many important human viral pathogens, the identification and characterization of new human monoclonal antibodies (hmabs) that are able to neutralize viruses offers the possibility for effective pre- and/or post-exposure therapeutic modalities. such hmabs may also help in our understanding of the virus entry process, the mechanisms of vi ...200919252850
mamu-a01/k(b) transgenic and mhc class i knockout mice as a tool for hiv vaccine development.we have developed a murine model expressing the rhesus macaque (rm) mamu-a01 mhc allele to characterize immune responses and vaccines based on antigens of importance to human disease processes. towards that goal, transgenic (tg) mice expressing chimeric rm (alpha1 and alpha2 mamu-a01 domains) and murine (alpha3, transmembrane, and cytoplasmic h-2k(b) domains) mhc class i molecules were derived by transgenesis of the h-2k(b)d(b) double mhc class i knockout strain. after immunization of mamu-a01/k ...200919249807
generating aptamers for recognition of virus-infected cells.the development of molecular probes capable of recognizing virus-infected cells is essential to meet the serious clinical, therapeutic, and national-security challenges confronting virology today. we report the development of dna aptamers as probes for the selective targeting of virus-infected living cells.200919246617
dideoxy fluoro-ketopyranosyl nucleosides as potent antiviral agents: synthesis and biological evaluation of 2,3- and 3,4-dideoxy-3-fluoro-4- and -2-keto-beta-d-glucopyranosyl derivatives of n(4)-benzoyl cytosine.the synthesis of the dideoxy fluoro ketopyranonucleoside analogues, 1-(2,3-dideoxy-3-fluoro-6-o-trityl-beta-d-glycero-hexopyranosyl-4-ulose)-n(4)-benzoyl cytosine (7a), 1-(3,4-dideoxy-3-fluoro-6-o-trityl-beta-d-glycero-hexopyranosyl-2-ulose)-n(4)-benzoyl cytosine (13a) and their detritylated analogues 8a and 14a, respectively, is described. condensation of peracetylated 3-deoxy-3-fluoro-d-glucopyranose (1) with silylated n(4)-benzoyl cytosine, followed by selective deprotection and isopropyliden ...200919246130
natural human infections with vaccinia virus during bovine vaccinia outbreaks.bovine vaccinia is an exanthematic disease caused by vaccinia virus (vacv). this zoonosis has been associated with several cases of bovine infection, particularly in milk herds. farmers, milkers and their close contacts developed lesions on the hands, forearms, legs and face accompanied by fever, headache, malaise, myalgia and axillary, inguinal and cervical lymphadenopathy. vacv infections have a significant public health impact due to their occupational character, high frequency of transmissio ...200919243990
preclinical and clinical development of a multi-envelope, dna-virus-protein (d-v-p) hiv-1 vaccine.the human immune system has evolved to recognize antigenic diversity, a strength that has been harnessed by vaccine developers to combat numerous pathogens (e.g., pneumococcus, influenza virus, rotavirus). in each case, vaccine cocktails were formulated to include antigenic variants of the target. to combat hiv-1 diversity, we assembled a cocktail vaccine comprising dozens of envelopes, delivered as recombinant dna, vaccinia virus, and protein for testing in a clinical trial. one vaccinee has no ...200919241253
vaccinia virus-based multivalent h5n1 avian influenza vaccines adjuvanted with il-15 confer sterile cross-clade protection in mice.the potential for a global influenza pandemic remains significant with epidemiologic and ecologic indicators revealing the entrenchment of the highly pathogenic avian influenza a h5n1 in both wild bird populations and domestic poultry flocks in asia and in many african and european countries. indisputably, the single most effective public health intervention in mitigating the devastation such a pandemic could unleash is the availability of a safe and effective vaccine that can be rapidly deploye ...200919234203
fas ligand is required for the development of respiratory syncytial virus vaccine-enhanced disease.children immunized with a formalin-inactivated respiratory syncytial virus (rsv) vaccine experienced enhanced disease and exhibited pulmonary eosinophilia upon natural rsv infection. balb/c mice immunized with either formalin-inactivated rsv or a recombinant vaccinia virus (vacv) expressing the rsv attachment (g) protein develop extensive pulmonary eosinophilia after rsv challenge that mimics the eosinophilic response observed in the children during the 1960s vaccine trials. fas ligand (fasl) is ...200919234198
preferential use of b7.2 and not b7.1 in priming of vaccinia virus-specific cd8 t cells.recent studies have demonstrated that cd28 provides critical costimulatory signals required for optimal cd8 t cell expansion and effector function in response to several viruses, including influenza, hsv, and vaccinia virus (vacv). cd28 has two ligands expressed largely on professional apc, named b7.1 (cd80) and b7.2 (cd86). although some results suggest that these ligands are equivalent and both promote cd28 signaling, it is not clear whether they are equally important for priming of antiviral ...200919234186
programming for cd8 t cell memory development requires il-12 or type i ifn.inflammation can have both positive and negative effects on development of cd8 t cell memory, but the relative contributions and cellular targets of the cytokines involved are unclear. using cd8 t cells lacking receptors for il-12, type i ifn, or both, we show that these cytokines act directly on cd8 t cells to support memory formation in response to vaccinia virus and listeria monocytogenes infections. development of memory to vaccinia is supported predominantly by il-12, whereas both il-12 and ...200919234173
cutting edge: mucosal application of a lyophilized viral vector vaccine confers systemic and protective immunity toward intracellular pathogens.a major problem of current vaccines is storage stability, often requiring strict maintenance of cold chains. in the course of the eradication of smallpox, a freeze-dried vaccinia virus (dryvax), which proved to be very stable, was used to overcome this limitation. however, dryvax needs to be reconstituted before usage and is administered using a bifurcated needle, procedures that pose a number of additional health risks. we report in this study that a stable, lyophilized, modified vaccinia virus ...200919234150
[examination of biocides for their effectiveness against animal viruses according to european union standards with emphasis on the selection of a suitable test virus].because of the changes to be expected in the methods for testing disinfectants deemed to be used in the veterinary field, candidate viral species were evaluated for their suitability as test virus. considered viral species included different non-enveloped viruses [bovine enterovirus type 1 (ecbo (enteric cytopathogenic bovine orphan) virus), mammalian reovirus type 1, feline calici virus (fcv), and bovine parvovirus (bpv)], as well as enveloped viruses, as equine arteritisvirus (eav), bovine her ...200919226936
the 3'-to-5' exonuclease activity of vaccinia virus dna polymerase is essential and plays a role in promoting virus genetic recombination.poxviruses are subjected to extraordinarily high levels of genetic recombination during infection, although the enzymes catalyzing these reactions have never been identified. however, it is clear that virus-encoded dna polymerases play some unknown yet critical role in virus recombination. using a novel, antiviral-drug-based strategy to dissect recombination and replication reactions, we now show that the 3'-to-5' proofreading exonuclease activity of the viral dna polymerase plays a key role in ...200919224992
correlates of protection efficacy induced by vaccinia virus-specific cd8+ t-cell epitopes in the murine intranasal challenge model.the recent identification of a large array of different vaccinia virus-derived cd8(+) t-cell epitopes offers a unique opportunity to systematically analyze the correlation between protective efficacy and variables such as kinetics of expression and function of viral proteins, binding affinity to mhc molecules, immunogenicity, and viral antigen processing/presentation. in the current study, 49 different h-2(b) restricted epitopes were tested for their ability to protect peptide-immunized c57bl/6 ...200919224639
interleukin-18-related genes are induced during the contraction phase but do not play major roles in regulating the dynamics or function of the t-cell response to listeria monocytogenes infection.proinflammatory cytokines, such as gamma interferon (ifn-gamma), impact aspects of t-cell responses after infection, including expansion, contraction, and memory formation. interleukin-18 (il-18) functions as a proinflammatory cytokine by stimulating the production of ifn-gamma from multiple cell types and accentuating the development of th1 cd4 t-cell responses. focused microarray analyses revealed upregulation of il-18 and il-18 receptor genes in cd8 t cells during the contraction phase. based ...200919223481
high-affinity human leucocyte antigen class i binding variola-derived peptides induce cd4+ t cell responses more than 30 years post-vaccinia virus vaccination.interferon-gamma secreting t lymphocytes against pox virus-derived synthetic 9-mer peptides were tested by enzyme-linked immunospot in peripheral blood of individuals vaccinated with vaccinia virus more than 30 years ago. the peptides were characterized biochemically as high-affinity human leucocyte antigen (hla) class i binders (k(d) <or= 5 nm). however, five of the individuals tested did not show typical cd8(+) t cell-mediated hla class i-restricted responses. instead, these donors showed cd4( ...200919220834
investigation of orf virus structure and morphogenesis using recombinants expressing flag-tagged envelope structural proteins: evidence for wrapped virus particles and egress from infected cells.orf virus (orfv) is the type species of the genus parapoxvirus, but little is known about the structure or morphogenesis of the virus. in contrast, the structure and morphogenesis of vaccinia virus (vacv) has been extensively studied. vacv has two main infectious forms, mature virion (mv) and extracellular virion (ev). the mv is wrapped by two additional membranes derived from the trans-golgi to produce a wrapped virion (wv), the outermost of which is lost by cellular membrane fusion during vira ...200919218206
expression of the highly conserved vaccinia virus e6 protein is required for virion morphogenesis.the vaccinia virus e6r gene (vacvwr062) is conserved in all members of the poxvirus family and encodes a protein associated with the mature virion. we confirmed this association and provided evidence for an internal location. an inducible mutant that conditionally expresses e6 was constructed. in the absence of inducer, plaque formation and virus production were severely inhibited in several cell lines, whereas some replication occurred in others. this difference could be due to variation in the ...200919217136
expression and characterization of bovine lactoperoxidase by recombinant vaccinia virus.lactoperoxidase (lpo) is a 78 kda heme-containing oxidation-reduction enzyme present in milk, found in physiological fluids of mammals. lpo has an antimicrobial activity, and presumably contribute to the protective functions of milk against infectious diseases. in this study, recombinant vaccinia virus expressing bovine lpo (vv/blpo) was constructed. in rabbit kidney (rk13) cells infected with vv/blpo, recombinant blpo was detected in both cell extracts and culture supernatants. tunicamycin trea ...200919214766
gamma interferon-induced interferon regulatory factor 1-dependent antiviral response inhibits vaccinia virus replication in mouse but not human fibroblasts.vaccinia virus (vacv) replicates in mouse and human fibroblasts with comparable kinetics and efficiency, yielding similar titers of infectious progeny. here we demonstrate that gamma interferon (ifn-gamma) but not ifn-alpha or ifn-beta pretreatment of mouse fibroblasts prior to vacv infection induces a long-lasting antiviral state blocking vacv replication. in contrast, high doses of ifn-gamma failed to establish an antiviral state in human fibroblasts. in mouse fibroblasts, ifn-gamma impeded th ...200919211768
pi3k signaling regulates rapamycin-insensitive translation initiation complex formation in vaccinia virus-infected cells.how vaccinia virus (vv) regulates assembly of the host translation initiation complex eif4f remains unclear. here, we show that vv activated host pi3k to stimulate downstream mammalian target of rapamycin (mtor), a kinase that inactivates the translational repressor 4e-bp1. however, although the mtor inhibitor rapamycin suppressed vv-induced inactivation of 4e-bp1, it failed to inhibit eif4f assembly. in contrast, pi3k inhibition in vv-infected cells increased the abundance of hypophosphorylated ...200919211763
poxvirus host range protein cp77 contains an f-box-like domain that is necessary to suppress nf-kappab activation by tumor necrosis factor alpha but is independent of its host range function.tumor necrosis factor alpha (tnf-alpha) activates the nuclear factor kappab (nf-kappab) signaling pathway that regulates expression of many cellular factors playing important roles in innate immune responses and inflammation in infected hosts. poxviruses employ many strategies to inhibit nf-kappab activation in cells. in this report, we describe a poxvirus host range protein, cp77, which blocked nf-kappab activation by tnf-alpha. immunofluorescence analyses revealed that nuclear translocation of ...200919211746
essential role for either trs1 or irs1 in human cytomegalovirus replication.viral infections often produce double-stranded rna (dsrna), which in turn triggers potent antiviral responses, including the global repression of protein synthesis mediated by protein kinase r (pkr) and 2'-5' oligoadenylate synthetase (oas). as a consequence, many viruses have evolved genes, such as those encoding dsrna-binding proteins, which counteract these pathways. human cytomegalovirus (hcmv) encodes two related proteins, ptrs1 and pirs1, which bind dsrna and can prevent activation of the ...200919211736
dimeric quaternary structure of the prototypical dual specificity phosphatase vh1.the vaccinia virus h1 gene product, vh1, is a dual specificity phosphatase that down-regulates the cellular antiviral response by dephosphorylating stat1. the crystal structure of vh1, determined at 1.32 a resolution, reveals a novel dimeric quaternary structure, which exposes two active sites spaced approximately 39 a away from each other. vh1 forms a stable dimer via an extensive domain swap of the n-terminal helix (residues 1-20). in vitro, vh1 can dephosphorylate activated stat1, in a reacti ...200919211553
characterization of the vaccinia virus d10 decapping enzyme provides evidence for a two-metal-ion mechanism.decapping enzymes are required for the removal of the 5'-end cap of mrnas. these enzymes exhibit a specific hydrolase activity, resulting in cleavage between the alpha- and beta-phosphates of the m7gpppn cap to generate both m7gdp and monophosphorylated rna products. decapping enzymes have been found in humans, plants and yeasts, and have been discovered more recently in vaccinia virus (d10 protein). although experimental evidences are lacking, three-metal- and two-metal-ion mechanisms have been ...200919210265
sars-cov spike proteins expressed by the vaccinia virus tiantan strain: secreted sq protein induces robust neutralization antibody in mice.the spike (s) glycoprotein of severe acute respiratory syndrome coronavirus (sars-cov) is a major target in the development of diagnostic assays and vaccines, but its antigenic and immunogenic properties remain unclear. seven sars-cov spike proteins (s, sq, s1, rbd, s2, s2q, and cx) were generated using the modified vaccinia virus (tiantan strain) as a vector, and their antigenicity and immunogenicity were evaluated. the secreted sq protein in which the transmembrane domain was deleted, as well ...200919210229
an e2-f12 complex is required for intracellular enveloped virus morphogenesis during vaccinia infection.the vaccinia virus protein, f12, has been suggested to play an important role in microtubule-based transport of intracellular enveloped virus (iev). we found that gfp-f12 is recruited to iev moving on microtubules but is released from virus particles when they switch to actin-based motility. in the absence of f12, although the majority of iev remain close to their peri-nuclear site of assembly, a small number of iev still move with linear trajectories at speeds of 0.85 μm s(-1) , consistent with ...200919207726
recombinant measles viruses expressing single or multiple antigens of human immunodeficiency virus (hiv-1) induce cellular and humoral immune responses.recombinant measles viruses (rmv) based on the live attenuated measles vaccine strain (mvb) expressing antigens of hiv-1 clade b were generated by reverse genetics. recombinants expressing single or double antigens of hiv-1 (rmv-hiv) were genetically highly stable on human diploid cells. the production process of these viruses was essentially similar to the parental mv strain, yielding comparative end titers. immunization of tg-mice by different regimens and formulations showed potent humoral an ...200919200842
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