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  1 / 8225 MEDLINE  
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[PMID]:28456791
[Au] Autor:Dondero A; Casu B; Bellora F; Vacca A; De Luisi A; Frassanito MA; Cantoni C; Gaggero S; Olive D; Moretta A; Bottino C; Castriconi R
[Ad] Endereço:Department of Experimental Medicine (DIMES), University of Genova, 16132 Genova, Italy.
[Ti] Título:NK cells and multiple myeloma-associated endothelial cells: molecular interactions and influence of IL-27.
[So] Source:Oncotarget;8(21):35088-35102, 2017 May 23.
[Is] ISSN:1949-2553
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Angiogenesis represents a hallmark of tumor progression in Multiple Myeloma (MM), a still incurable malignancy. Here we analyzed the activity of cytokine-stimulated NK cells against tumor-associated endothelial cells isolated from bone marrow aspirates of MM patients with active disease (MMECs). We show that NK cells activated with optimal doses of IL-15 killed MMECs thanks to the concerted action of multiple activating receptors. In particular, according to the high expression of PVR and Nectin-2 on MMECs, DNAM-1 actively participated in target recognition. Interestingly, in MMECs the surface density of PVR was significantly higher than that detected in endothelium from patients with MM in complete remission or with monoclonal gammopathy of undetermined significance (MGUS). Importantly, IL-27, which unlike IL-15 does not display pro-angiogenic properties, maintained or increased the NK cell functions induced by suboptimal concentrations of IL-15. NK cell properties included killing of MMECs, IFN-γ production as well as a peculiar increase of NKp46 expression on NK cell surface. Finally, IL-27 showed a striking capability of up-regulating the expression of PD-L2 and HLA-I on tumor endothelium, whereas it did not modify that of PD-L1 and HLA-II.Our results suggest that cytokine-activated endogenous or adoptively transferred NK cells might support conventional therapies improving the outcome of MM patients.
[Mh] Termos MeSH primário: Células Endoteliais/efeitos dos fármacos
Interleucinas/metabolismo
Células Matadoras Naturais/efeitos dos fármacos
Mieloma Múltiplo/imunologia
[Mh] Termos MeSH secundário: Idoso
Células Endoteliais/citologia
Células Endoteliais/metabolismo
Feminino
Seres Humanos
Interleucina-15/farmacologia
Células Matadoras Naturais/citologia
Células Matadoras Naturais/metabolismo
Masculino
Meia-Idade
Mieloma Múltiplo/metabolismo
Neovascularização Patológica
Receptores Virais/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (IL27 protein, human); 0 (Interleukin-15); 0 (Interleukins); 0 (Receptors, Virus); 0 (poliovirus receptor)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170501
[St] Status:MEDLINE
[do] DOI:10.18632/oncotarget.17070


  2 / 8225 MEDLINE  
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[PMID]:29324755
[Au] Autor:Saracino A; Cozzi-Lepri A; Shanyinde M; Ceccherini Silberstein F; Nozza S; Di Biagio A; Cassola G; Bruno G; Capobianchi M; Puoti M; Monno L; d'Arminio Monforte A; ICONA Foundation Study
[Ad] Endereço:Clinic of Infectious Diseases, University of Bari, Bari, Italy.
[Ti] Título:HIV-1 co-receptor tropism and liver fibrosis in HIV-infected patients.
[So] Source:PLoS One;13(1):e0190302, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: In vitro, gp120 of both X4 and R5 HIV-1 strains activates human hepatic stellate cells, but if it can promote liver fibrosis in vivo is unknown. We aimed to evaluate if patients carrying X4 or R5 strains have a different liver fibrosis (LF) progression over time. METHODS: A total of 1,137 HIV-infected patients in ICONA cohort (21% females, 7% HCV co-infected) with an available determination of HIV-1 co-receptor tropism (CRT), a Fibrosis-4 Index for Liver Fibrosis (FIB-4) <3.25 and at least one-year follow-up were included. CRT was assessed by gp120 sequencing on plasma RNA and geno2pheno algorithm (10% false positive rate) or by Trofile. LF was assessed by means of FIB-4. LF progression was defined as an absolute score increase or a transition to higher fibrosis stratum and/or occurrence of liver-related clinical events. RESULTS: A total of 249 (22%) patients carried X4 strains, which were associated with older age, lower CD4 count, lower nadir CD4, and intravenous drug use. Overall, X4 and R5 patients had similar baseline FIB-4 scores and similar mean FIB-4 slope after a median follow-up of 35 months. There was no difference between X4 and R5 for time to LF progression (p = 0.925). Estimated risk of LF at 24 months (95% CI) after baseline in X4 and R5 was 10.6% (8.3-12.9) and 9.9% (5.9-14.0), respectively. Age, HCV co-infection, diabetes, HIV-duration, HIV-RNA>100.000 cp/mL, antiretroviral therapy exposure were associated with LF progression at multivariate analysis. CONCLUSIONS: A slight LF progression over time was observed in HIV-infected patients. No difference was demonstrated for X4 and R5 HIV-1 strains in accelerating LF evolution.
[Mh] Termos MeSH primário: Infecções por HIV/complicações
HIV-1/fisiologia
Cirrose Hepática/complicações
Tropismo Viral/fisiologia
[Mh] Termos MeSH secundário: Fármacos Anti-HIV/uso terapêutico
Feminino
Infecções por HIV/tratamento farmacológico
Seres Humanos
Masculino
Receptores Virais/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-HIV Agents); 0 (Receptors, Virus)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180206
[Lr] Data última revisão:
180206
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180112
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0190302


  3 / 8225 MEDLINE  
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[PMID]:28745308
[Au] Autor:Zhang X; Shi J; Ye X; Ku Z; Zhang C; Liu Q; Huang Z
[Ad] Endereço:Unit of Vaccinology &Antiviral Strategies, CAS Key Laboratory of Molecular Virology &Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai 200031, China.
[Ti] Título:Coxsackievirus A16 utilizes cell surface heparan sulfate glycosaminoglycans as its attachment receptor.
[So] Source:Emerg Microbes Infect;6(7):e65, 2017 Jul 26.
[Is] ISSN:2222-1751
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Coxsackievirus A16 (CVA16) is one of the major pathogens responsible for hand, foot and mouth disease, which affects more than two million children in the Asian-Pacific region annually. Previous studies have shown that scavenger receptor B2 is a functional receptor for CVA16 that facilitates the uncoating process. However, it remains unclear whether other receptors are required for efficient CVA16 infection. In this study, by using a variety of assays we demonstrated that CVA16 utilizes surface heparan sulfate glycosaminoglycans as its attachment receptor. We further showed that five surface-exposed positively charged residues located in a cluster at the five-fold vertex of the virion are critical to heparan sulfate binding and cellular attachment of CVA16. Among the five residues, the arginine at position 166 (R166) of VP1 capsid protein appeared to be the most important for the interaction between CVA16 and heparan sulfate. Alanine substitution at this site (R166A) almost completely abolished heparan sulfate binding and cellular attachment of the virus. Our work achieves insight into the early events of CVA16 infection, thereby providing information that may facilitate the rational design of antiviral drugs and vaccines against CVA16 infection.
[Mh] Termos MeSH primário: Enterovirus Humano A/fisiologia
Heparitina Sulfato/metabolismo
Receptores Virais/metabolismo
Ligação Viral
[Mh] Termos MeSH secundário: Alanina
Substituição de Aminoácidos
Animais
Arginina
Proteínas do Capsídeo/química
Proteínas do Capsídeo/metabolismo
Cercopithecus aethiops
Enterovirus Humano A/química
Heparitina Sulfato/química
Seres Humanos
Receptores Virais/química
Células Vero
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Capsid Proteins); 0 (Receptors, Virus); 0 (VP1 protein, Foot-and-mouth disease virus); 9050-30-0 (Heparitin Sulfate); 94ZLA3W45F (Arginine); OF5P57N2ZX (Alanine)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180118
[Lr] Data última revisão:
180118
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170727
[St] Status:MEDLINE
[do] DOI:10.1038/emi.2017.55


  4 / 8225 MEDLINE  
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[PMID]:28977405
[Au] Autor:van der Lee R; Wiel L; van Dam TJP; Huynen MA
[Ad] Endereço:Centre for Molecular and Biomolecular Informatics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.
[Ti] Título:Genome-scale detection of positive selection in nine primates predicts human-virus evolutionary conflicts.
[So] Source:Nucleic Acids Res;45(18):10634-10648, 2017 Oct 13.
[Is] ISSN:1362-4962
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Hotspots of rapid genome evolution hold clues about human adaptation. We present a comparative analysis of nine whole-genome sequenced primates to identify high-confidence targets of positive selection. We find strong statistical evidence for positive selection in 331 protein-coding genes (3%), pinpointing 934 adaptively evolving codons (0.014%). Our new procedure is stringent and reveals substantial artefacts (20% of initial predictions) that have inflated previous estimates. The final 331 positively selected genes (PSG) are strongly enriched for innate and adaptive immunity, secreted and cell membrane proteins (e.g. pattern recognition, complement, cytokines, immune receptors, MHC, Siglecs). We also find evidence for positive selection in reproduction and chromosome segregation (e.g. centromere-associated CENPO, CENPT), apolipoproteins, smell/taste receptors and mitochondrial proteins. Focusing on the virus-host interaction, we retrieve most evolutionary conflicts known to influence antiviral activity (e.g. TRIM5, MAVS, SAMHD1, tetherin) and predict 70 novel cases through integration with virus-human interaction data. Protein structure analysis further identifies positive selection in the interaction interfaces between viruses and their cellular receptors (CD4-HIV; CD46-measles, adenoviruses; CD55-picornaviruses). Finally, primate PSG consistently show high sequence variation in human exomes, suggesting ongoing evolution. Our curated dataset of positive selection is a rich source for studying the genetics underlying human (antiviral) phenotypes. Procedures and data are available at https://github.com/robinvanderlee/positive-selection.
[Mh] Termos MeSH primário: Evolução Molecular
Seleção Genética
[Mh] Termos MeSH secundário: Animais
Artefatos
Conversão Gênica
Variação Genética
Genômica
Interações Hospedeiro-Patógeno/genética
Seres Humanos
Imunidade/genética
Família Multigênica
Primatas/genética
Proteínas/genética
Receptores Virais/química
Proteínas Virais/química
Viroses/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Proteins); 0 (Receptors, Virus); 0 (Viral Proteins)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171107
[Lr] Data última revisão:
171107
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171005
[St] Status:MEDLINE
[do] DOI:10.1093/nar/gkx704


  5 / 8225 MEDLINE  
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[PMID]:28863277
[Au] Autor:Naguib MM; Arafa AS; Parvin R; Beer M; Vahlenkamp T; Harder TC
[Ad] Endereço:Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Suedufer 10, Greifswald Insel-Riems 17493, Germany; National Laboratory for Veterinary Quality Control on Poultry Production, Animal Health Research Institute, Giza 12618, Egypt.
[Ti] Título:Insights into genetic diversity and biological propensities of potentially zoonotic avian influenza H9N2 viruses circulating in Egypt.
[So] Source:Virology;511:165-174, 2017 Nov.
[Is] ISSN:1096-0341
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Low pathogenic avian influenza (LPAI) H9N2 viruses have established endemic status in Egyptian poultry populations since 2012. Recently, four cases of human H9N2 virus infections in Egypt demonstrated the zoonotic potential of these viruses. Egyptian H9N2 viruses obtained from 2011 to 2014 phylogenetically grouped into three clusters (1-3) within subclade B of the G1 lineage. Antigenically, a close clustering of the Egyptian H9N2 viruses with other recent G1-B like H9N2 strains and a significant antigenic distance from viruses outside the G1-B lineage was evident. Recent Egyptian LPAIV H9N2 showed a tendency to increased binding with erythrocytes expressing α 2,6-linked sialic acid which correlated with the Q226L amino acid substitution at the receptor binding unit of the hemagglutinin (Q234L, H9 numbering). Sequence analyses of the N2 neuraminidase (NA) revealed substitutions in the NA hemadsorption site similar to the N2 of prepandemic H3N2/1968, but no distinct antigenic or functional characteristics of the H9N2 NA associated with increased zoonotic potential could be identified.
[Mh] Termos MeSH primário: Variação Genética
Vírus da Influenza A Subtipo H9N2/classificação
Vírus da Influenza A Subtipo H9N2/genética
Influenza Aviária/virologia
Influenza Humana/virologia
Zoonoses/virologia
[Mh] Termos MeSH secundário: Animais
Análise por Conglomerados
Egito
Genótipo
Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética
Seres Humanos
Vírus da Influenza A Subtipo H9N2/isolamento & purificação
Vírus da Influenza A Subtipo H9N2/fisiologia
Neuraminidase/genética
Filogenia
Aves Domésticas
Receptores Virais/metabolismo
Sorogrupo
Ácidos Siálicos/metabolismo
Proteínas Virais/genética
Ligação Viral
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Hemagglutinin Glycoproteins, Influenza Virus); 0 (Receptors, Virus); 0 (Sialic Acids); 0 (Viral Proteins); EC 3.2.1.18 (NA protein, influenza A virus); EC 3.2.1.18 (Neuraminidase)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171010
[Lr] Data última revisão:
171010
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170902
[St] Status:MEDLINE


  6 / 8225 MEDLINE  
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[PMID]:28809154
[Au] Autor:Hu K; He S; Xiao J; Li M; Luo S; Zhang M; Hu Q
[Ad] Endereço:2​Institute for Infection and Immunity, St George's University of London, London SW17 0RE, UK 1​State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China.
[Ti] Título:Interaction between herpesvirus entry mediator and HSV-2 glycoproteins mediates HIV-1 entry of HSV-2-infected epithelial cells.
[So] Source:J Gen Virol;98(9):2351-2361, 2017 Sep.
[Is] ISSN:1465-2099
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Herpes simplex virus type 2 (HSV-2) increases human immunodeficiency virus type 1 (HIV-1) acquisition and transmission via unclear mechanisms. Herpesvirus entry mediator (HVEM), an HSV-2 entry receptor, is highly expressed on HIV-1 target cells (CD4+ T cells) and may be incorporated into HIV-1 virions, while HSV-2 glycoproteins can be present on the infected cell surface. Since HVEM-gD interaction together with gB/gH/gL is essential for HSV-2 entry, HVEM-bearing HIV-1 (HIV-1/HVEM) may enter HSV-2-infected cells through such interactions. To test this hypothesis, we first confirmed the presence of HVEM on HIV-1 virions and glycoproteins on the HSV-2-infected cell surface. Additional studies showed that HIV-1/HVEM bound to the HSV-2-infected cell surface in an HSV-2 infection-time-dependent manner via HVEM-gD interaction. HIV-1/HVEM entry of HSV-2-infected cells was dependent on HVEM-gD interaction and the presence of gB/gH/gL, and was inhibited by azidothymidine. Furthermore, peripheral blood mononuclear cell-derived HIV-1 infected HSV-2-infected primary foreskin epithelial cells and the infection was inhibited by anti-HVEM/gD antibodies. Together, our results indicate that HIV-1 produced from CD4+ T cells bears HSV-2 receptor HVEM and can bind to and enter HSV-2-infected epithelial cells depending on HVEM-gD interaction and the presence of gB/gH/gL. Our findings provide a potential new mechanism underlying HSV-2 infection-enhanced HIV-1 mucosal transmission and may shed light on HIV-1 prevention.
[Mh] Termos MeSH primário: Células Epiteliais/metabolismo
Infecções por HIV/metabolismo
HIV-1/fisiologia
Herpes Simples/metabolismo
Herpesvirus Humano 2/fisiologia
Membro 14 de Receptores do Fator de Necrose Tumoral/metabolismo
Receptores Virais/metabolismo
Proteínas do Envelope Viral/metabolismo
[Mh] Termos MeSH secundário: Animais
Linfócitos T CD4-Positivos/virologia
Células CHO
Cricetulus
Células Epiteliais/virologia
Infecções por HIV/genética
Infecções por HIV/virologia
HIV-1/genética
Herpes Simples/genética
Herpesvirus Humano 2/genética
Seres Humanos
Camundongos
Ligação Proteica
Membro 14 de Receptores do Fator de Necrose Tumoral/genética
Receptores Virais/genética
Proteínas do Envelope Viral/genética
Internalização do Vírus
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Receptors, Tumor Necrosis Factor, Member 14); 0 (Receptors, Virus); 0 (Viral Envelope Proteins); 0 (glycoprotein B, herpes simplex virus type 2); 0 (glycoprotein D-herpes simplex virus type 2)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170919
[Lr] Data última revisão:
170919
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170816
[St] Status:MEDLINE
[do] DOI:10.1099/jgv.0.000895


  7 / 8225 MEDLINE  
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[PMID]:28800489
[Au] Autor:Lin Y; Racaniello VR
[Ad] Endereço:Department of Microbiology&Immunology, Columbia University College of Physicians&Surgeons, 701W. 168th St., New York, NY 10032, USA.
[Ti] Título:Polioviruses that bind a chimeric Pvr-nectin-2 protein identify capsid residues involved in receptor interaction.
[So] Source:Virology;510:305-315, 2017 Oct.
[Is] ISSN:1096-0341
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Amino acid changes in the C'C"D region in poliovirus receptor domain 1 disrupt poliovirus binding. To examine further the role of the C'C"D region in poliovirus infection, we substituted this region of Pvr into the corresponding region of a murine homolog, nectin-2. The chimeric receptor, nectin-2 , rendered transformed L cells susceptible to infection with poliovirus P1/Mahoney, but not with polioviruses P2/Lansing and P3/Leon, due to lack of binding. Twenty-four variants of P2/Lansing were selected that replicate in nectin-2 producing cell lines. Sequence analysis revealed 30 amino acid changes at 28 capsid residues. One change, K1103R, is found in nearly all isolates and is located at one end of the VP1 BC loop. Other alterations are located on the canyon surface, at the protomer interface, and along the perimeter of the canyon south wall. Unlike poliovirus-Pvr binding, the VP1 BC loop is required for infection of cells producing nectin-2 .
[Mh] Termos MeSH primário: Capsídeo/metabolismo
Moléculas de Adesão Celular/metabolismo
Poliovirus/fisiologia
Receptores Virais/metabolismo
Proteínas Recombinantes de Fusão/metabolismo
Ligação Viral
[Mh] Termos MeSH secundário: Animais
Moléculas de Adesão Celular/genética
Linhagem Celular
Análise Mutacional de DNA
Seres Humanos
Camundongos
Nectinas
Receptores Virais/genética
Proteínas Recombinantes de Fusão/genética
Replicação Viral
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cell Adhesion Molecules); 0 (Nectins); 0 (Receptors, Virus); 0 (Recombinant Fusion Proteins); 0 (poliovirus receptor)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170812
[St] Status:MEDLINE


  8 / 8225 MEDLINE  
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[PMID]:28794032
[Au] Autor:Bamunusinghe D; Liu Q; Plishka R; Dolan MA; Skorski M; Oler AJ; Yedavalli VRK; Buckler-White A; Hartley JW; Kozak CA
[Ad] Endereço:Laboratory of Molecular Microbiology, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland, USA.
[Ti] Título:Recombinant Origins of Pathogenic and Nonpathogenic Mouse Gammaretroviruses with Polytropic Host Range.
[So] Source:J Virol;91(21), 2017 Nov 01.
[Is] ISSN:1098-5514
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Ecotropic, xenotropic, and polytropic mouse leukemia viruses (E-, X-, and P-MLVs) exist in mice as infectious viruses and endogenous retroviruses (ERVs) inserted into mouse chromosomes. All three MLV subgroups are linked to leukemogenesis, which involves generation of recombinants with polytropic host range. Although P-MLVs are deemed to be the proximal agents of disease induction, few biologically characterized infectious P-MLVs have been sequenced for comparative analysis. We analyzed the complete genomes of 16 naturally occurring infectious P-MLVs, 12 of which were typed for pathogenic potential. We sought to identify ERV progenitors, recombinational hot spots, and segments that are always replaced, never replaced, or linked to pathogenesis or host range. Each P-MLV has an E-MLV backbone with P- or X-ERV replacements that together cover 100% of the recombinant genomes, with different substitution patterns for X- and P-ERVs. Two segments are always replaced, both coding for envelope (Env) protein segments: the N terminus of the surface subunit and the cytoplasmic tail R peptide. Viral gene replacements are influenced by host restriction genes and Pathogenic potential maps to the transmembrane subunit segment encoding the N-heptad repeat (HR1). Molecular dynamics simulations identified three novel interdomain salt bridges in the lymphomagenic virus HR1 that could affect structural stability, entry or sensitivity to host immune responses. The long terminal repeats of lymphomagenic P-MLVs are differentially altered by recombinations, duplications, or mutations. This analysis of the naturally occurring, sometimes pathogenic P-MLV recombinants defines the limits and extent of intersubgroup recombination and identifies specific sequence changes linked to pathogenesis and host interactions. During virus-induced leukemogenesis, ecotropic mouse leukemia viruses (MLVs) recombine with nonecotropic endogenous retroviruses (ERVs) to produce polytropic MLVs (P-MLVs). Analysis of 16 P-MLV genomes identified two segments consistently replaced: one at the envelope N terminus that alters receptor choice and one in the R peptide at the envelope C terminus, which is removed during virus assembly. Genome-wide analysis shows that nonecotropic replacements in the progenitor ecotropic MLV genome are more extensive than previously appreciated, covering 100% of the genome; contributions from xenotropic and polytropic ERVs differentially alter the regions responsible for receptor determination or subject to APOBEC3 and Fv1 restriction. All pathogenic viruses had modifications in the regulatory elements in their long terminal repeats and differed in a helical segment of envelope involved in entry and targeted by the host immune system. Virus-induced leukemogenesis thus involves generation of complex recombinants, and specific replacements are linked to pathogenesis and host restrictions.
[Mh] Termos MeSH primário: Especificidade de Hospedeiro/genética
Vírus da Leucemia Murina/classificação
Vírus da Leucemia Murina/patogenicidade
Leucemia Experimental/virologia
Infecções por Retroviridae/virologia
Infecções Tumorais por Vírus/virologia
Proteínas Virais/genética
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Animais
Sequência de Bases
Evolução Molecular
Genoma Viral
Vírus da Leucemia Murina/genética
Camundongos
Simulação de Dinâmica Molecular
Conformação Proteica
Receptores Virais/genética
Receptores Virais/metabolismo
Homologia de Sequência
Sequências Repetidas Terminais
Proteínas Virais/química
Proteínas Virais/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Receptors, Virus); 0 (Viral Proteins)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171109
[Lr] Data última revisão:
171109
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170811
[St] Status:MEDLINE


  9 / 8225 MEDLINE  
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[PMID]:28759649
[Au] Autor:Earnest JT; Hantak MP; Li K; McCray PB; Perlman S; Gallagher T
[Ad] Endereço:Department of Microbiology and Immunology, Loyola University Medical Center, Maywood, IL, United States of America.
[Ti] Título:The tetraspanin CD9 facilitates MERS-coronavirus entry by scaffolding host cell receptors and proteases.
[So] Source:PLoS Pathog;13(7):e1006546, 2017 Jul.
[Is] ISSN:1553-7374
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Infection by enveloped coronaviruses (CoVs) initiates with viral spike (S) proteins binding to cellular receptors, and is followed by proteolytic cleavage of receptor-bound S proteins, which prompts S protein-mediated virus-cell membrane fusion. Infection therefore requires close proximity of receptors and proteases. We considered whether tetraspanins, scaffolding proteins known to facilitate CoV infections, hold receptors and proteases together on cell membranes. Using knockout cell lines, we found that the tetraspanin CD9, but not the tetraspanin CD81, formed cell-surface complexes of dipeptidyl peptidase 4 (DPP4), the MERS-CoV receptor, and the type II transmembrane serine protease (TTSP) member TMPRSS2, a CoV-activating protease. This CD9-facilitated condensation of receptors and proteases allowed MERS-CoV pseudoviruses to enter cells rapidly and efficiently. Without CD9, MERS-CoV viruses were not activated by TTSPs, and they trafficked into endosomes to be cleaved much later and less efficiently by cathepsins. Thus, we identified DPP4:CD9:TTSP as the protein complexes necessary for early, efficient MERS-CoV entry. To evaluate the importance of these complexes in an in vivo CoV infection model, we used recombinant Adenovirus 5 (rAd5) vectors to express human DPP4 in mouse lungs, thereby sensitizing the animals to MERS-CoV infection. When the rAd5-hDPP4 vectors co-expressed small RNAs silencing Cd9 or Tmprss2, the animals were significantly less susceptible, indicating that CD9 and TMPRSS2 facilitated robust in vivo MERS-CoV infection of mouse lungs. Furthermore, the S proteins of virulent mouse-adapted MERS-CoVs acquired a CD9-dependent cell entry character, suggesting that CD9 is a selective agent in the evolution of CoV virulence.
[Mh] Termos MeSH primário: Infecções por Coronavirus/metabolismo
Infecções por Coronavirus/virologia
Dipeptidil Peptidase 4/metabolismo
Coronavírus da Síndrome Respiratória do Oriente Médio/fisiologia
Receptores Virais/metabolismo
Serina Endopeptidases/metabolismo
Tetraspanina-29/metabolismo
[Mh] Termos MeSH secundário: Animais
Infecções por Coronavirus/enzimologia
Infecções por Coronavirus/genética
Dipeptidil Peptidase 4/genética
Seres Humanos
Camundongos
Coronavírus da Síndrome Respiratória do Oriente Médio/genética
Receptores Virais/genética
Serina Endopeptidases/genética
Glicoproteína da Espícula de Coronavírus/genética
Glicoproteína da Espícula de Coronavírus/metabolismo
Tetraspanina 28/genética
Tetraspanina 28/metabolismo
Tetraspanina-29/genética
Internalização do Vírus
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Receptors, Virus); 0 (Spike Glycoprotein, Coronavirus); 0 (Tetraspanin 28); 0 (Tetraspanin-29); EC 3.4.14.5 (Dipeptidyl Peptidase 4); EC 3.4.21.- (Serine Endopeptidases); EC 3.4.21.- (TMPRSS2 protein, mouse)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170801
[St] Status:MEDLINE
[do] DOI:10.1371/journal.ppat.1006546


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[PMID]:28750037
[Au] Autor:Ilyushina NA; Lugovtsev VY; Samsonova AP; Sheikh FG; Bovin NV; Donnelly RP
[Ad] Endereço:Division of Biotechnology Research and Review II, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, Maryland, United States of America.
[Ti] Título:Generation and characterization of interferon-lambda 1-resistant H1N1 influenza A viruses.
[So] Source:PLoS One;12(7):e0181999, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Influenza A viruses pose a constant potential threat to human health. In view of the innate antiviral activity of interferons (IFNs) and their potential use as anti-influenza agents, it is important to know whether viral resistance to these antiviral proteins can arise. To examine the likelihood of emergence of IFN-λ1-resistant H1N1 variants, we serially passaged the A/California/04/09 (H1N1) strain in a human lung epithelial cell line (Calu-3) in the presence of increasing concentrations of recombinant IFN-λ1 protein. To monitor changes associated with adaptation of this virus to growth in Calu-3 cells, we also passaged the wild-type virus in the absence of IFN-λ1. Under IFN-λ1 selective pressure, the parental virus developed two neuraminidase (NA) mutations, S79L and K331N, which significantly reduced NA enzyme activity (↓1.4-fold) and sensitivity to IFN-λ1 (↓˃20-fold), respectively. These changes were not associated with a reduction in viral replication levels. Mutants carrying either K331N alone or S79L and K331N together induced weaker phosphorylation of IFN regulatory factor 3 (IRF3), and, as a consequence, much lower expression of the IFN genes (IFNB1, IFNL1 and IFNL2/3) and proteins (IFN-λ1 and IFN-λ2/3). The lower levels of IFN expression correlated with weaker induction of tyrosine-phosphorylated STAT1 and reduced RIG-I protein levels. Our findings demonstrate that influenza viruses can develop increased resistance to the antiviral activity of type III interferons.
[Mh] Termos MeSH primário: Farmacorresistência Viral/efeitos dos fármacos
Vírus da Influenza A Subtipo H1N1/genética
Vírus da Influenza A Subtipo H1N1/fisiologia
Interleucinas/farmacologia
[Mh] Termos MeSH secundário: Substituição de Aminoácidos/genética
Animais
Antivirais/farmacologia
Linhagem Celular
Proteína DEAD-box 58/metabolismo
RNA Polimerases Dirigidas por DNA/metabolismo
Cães
Ensaio de Imunoadsorção Enzimática
Regulação da Expressão Gênica/efeitos dos fármacos
Seres Humanos
Imunidade Inata/efeitos dos fármacos
Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos
Vírus da Influenza A Subtipo H1N1/crescimento & desenvolvimento
Fator Regulador 3 de Interferon/metabolismo
Mutação/genética
Neuraminidase/genética
Fosforilação/efeitos dos fármacos
Receptores Virais/genética
Recombinação Genética/genética
Fator de Transcrição STAT1/metabolismo
Análise de Sequência de DNA
Replicação Viral/efeitos dos fármacos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antiviral Agents); 0 (IL29 protein, human); 0 (IRF3 protein, human); 0 (Interferon Regulatory Factor-3); 0 (Interleukins); 0 (Receptors, Virus); 0 (STAT1 Transcription Factor); 0 (STAT1 protein, human); EC 2.7.7.6 (DNA-Directed RNA Polymerases); EC 3.2.1.18 (Neuraminidase); EC 3.6.1.- (DDX58 protein, human); EC 3.6.4.13 (DEAD Box Protein 58)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170929
[Lr] Data última revisão:
170929
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170728
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0181999



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