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1.
Cell ; 185(14): 2434-2451.e17, 2022 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-35764089

RESUMO

Multiple COVID-19 vaccines, representing diverse vaccine platforms, successfully protect against symptomatic COVID-19 cases and deaths. Head-to-head comparisons of T cell, B cell, and antibody responses to diverse vaccines in humans are likely to be informative for understanding protective immunity against COVID-19, with particular interest in immune memory. Here, SARS-CoV-2-spike-specific immune responses to Moderna mRNA-1273, Pfizer/BioNTech BNT162b2, Janssen Ad26.COV2.S, and Novavax NVX-CoV2373 were examined longitudinally for 6 months 100% of individuals made memory CD4+ T cells, with cTfh and CD4-CTL highly represented after mRNA or NVX-CoV2373 vaccination. mRNA vaccines and Ad26.COV2.S induced comparable CD8+ T cell frequencies, though only detectable in 60-67% of subjects at 6 months. A differentiating feature of Ad26.COV2.S immunization was a high frequency of CXCR3+ memory B cells. mRNA vaccinees had substantial declines in antibodies, while memory T and B cells were comparatively stable. These results may also be relevant for insights against other pathogens.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Ad26COVS1 , Anticorpos Antivirais , Vacina BNT162 , COVID-19/prevenção & controle , Humanos , Imunidade Humoral , Memória Imunológica , SARS-CoV-2
2.
Cell ; 185(5): 847-859.e11, 2022 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-35139340

RESUMO

We address whether T cell responses induced by different vaccine platforms (mRNA-1273, BNT162b2, Ad26.COV2.S, and NVX-CoV2373) cross-recognize early SARS-CoV-2 variants. T cell responses to early variants were preserved across vaccine platforms. By contrast, significant overall decreases were observed for memory B cells and neutralizing antibodies. In subjects ∼6 months post-vaccination, 90% (CD4+) and 87% (CD8+) of memory T cell responses were preserved against variants on average by AIM assay, and 84% (CD4+) and 85% (CD8+) preserved against Omicron. Omicron RBD memory B cell recognition was substantially reduced to 42% compared with other variants. T cell epitope repertoire analysis revealed a median of 11 and 10 spike epitopes recognized by CD4+ and CD8+ T cells, with average preservation > 80% for Omicron. Functional preservation of the majority of T cell responses may play an important role as a second-level defense against diverse variants.


Assuntos
Vacinas contra COVID-19/imunologia , Células B de Memória/imunologia , Células T de Memória/imunologia , SARS-CoV-2/imunologia , Ad26COVS1/administração & dosagem , Ad26COVS1/imunologia , Vacina BNT162/administração & dosagem , Vacina BNT162/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , COVID-19/patologia , COVID-19/prevenção & controle , COVID-19/virologia , Vacinas contra COVID-19/administração & dosagem , Epitopos/imunologia , Epitopos de Linfócito T/imunologia , Humanos , Células B de Memória/metabolismo , Células T de Memória/metabolismo , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinação
3.
Anesthesiology ; 141(1): 100-115, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38537025

RESUMO

BACKGROUND: Although it has been established that elevated blood pressure and its variability worsen outcomes in spontaneous intracerebral hemorrhage, antihypertensives use during the acute phase still lacks robust evidence. A blood pressure-lowering regimen using remifentanil and dexmedetomidine might be a reasonable therapeutic option given their analgesic and antisympathetic effects. The objective of this superiority trial was to validate the efficacy and safety of this blood pressure-lowering strategy that uses remifentanil and dexmedetomidine in patients with acute intracerebral hemorrhage. METHODS: In this multicenter, prospective, single-blinded, superiority randomized controlled trial, patients with intracerebral hemorrhage and systolic blood pressure (SBP) 150 mmHg or greater were randomly allocated to the intervention group (a preset protocol with a standard guideline management using remifentanil and dexmedetomidine) or the control group (standard guideline-based management) to receive blood pressure-lowering treatment. The primary outcome was the SBP control rate (less than 140 mmHg) at 1 h posttreatment initiation. Secondary outcomes included blood pressure variability, neurologic function, and clinical outcomes. RESULTS: A total of 338 patients were allocated to the intervention (n = 167) or control group (n = 171). The SBP control rate at 1 h posttreatment initiation in the intervention group was higher than that in controls (101 of 161, 62.7% vs. 66 of 166, 39.8%; difference, 23.2%; 95% CI, 12.4 to 34.1%; P < 0.001). Analysis of secondary outcomes indicated that patients in the intervention group could effectively reduce agitation while achieving lighter sedation, but no improvement in clinical outcomes was observed. Regarding safety, the incidence of bradycardia and respiratory depression was higher in the intervention group. CONCLUSIONS: Among intracerebral hemorrhage patients with a SBP 150 mmHg or greater, a preset protocol using a remifentanil and dexmedetomidine-based standard guideline management significantly increased the SBP control rate at 1 h posttreatment compared with the standard guideline-based management.


Assuntos
Anti-Hipertensivos , Pressão Sanguínea , Hemorragia Cerebral , Dexmedetomidina , Remifentanil , Humanos , Dexmedetomidina/uso terapêutico , Dexmedetomidina/administração & dosagem , Remifentanil/administração & dosagem , Remifentanil/uso terapêutico , Masculino , Feminino , Estudos Prospectivos , Hemorragia Cerebral/tratamento farmacológico , Idoso , Pessoa de Meia-Idade , Método Simples-Cego , Pressão Sanguínea/efeitos dos fármacos , Anti-Hipertensivos/uso terapêutico , Anti-Hipertensivos/administração & dosagem , Resultado do Tratamento , Hipnóticos e Sedativos/uso terapêutico
4.
J Virol ; 94(23)2020 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-32907979

RESUMO

Pandemic human immunodeficiency virus type 1 (HIV-1) is the result of the zoonotic transmission of simian immunodeficiency virus (SIV) from the chimpanzee subspecies Pan troglodytestroglodytes (SIVcpzPtt). The related subspecies Pan troglodytesschweinfurthii is the host of a similar virus, SIVcpzPts, which did not spread to humans. We tested these viruses with small-molecule capsid inhibitors (PF57, PF74, and GS-CA1) that interact with a binding groove in the capsid that is also used by CPSF6. While HIV-1 was sensitive to capsid inhibitors in cell lines, human macrophages, and peripheral blood mononuclear cells (PBMCs), SIVcpzPtt was resistant in rhesus FRhL-2 cells and human PBMCs but was sensitive to PF74 in human HOS and HeLa cells. SIVcpzPts was insensitive to PF74 in FRhL-2 cells, HeLa cells, PBMCs, and macrophages but was inhibited by PF74 in HOS cells. A truncated version of CPSF6 (CPSF6-358) inhibited SIVcpzPtt and HIV-1, while in contrast, SIVcpzPts was resistant to CPSF6-358. Homology modeling of HIV-1, SIVcpzPtt, and SIVcpzPts capsids and binding energy estimates suggest that these three viruses bind similarly to the host proteins cyclophilin A (CYPA) and CPSF6 as well as the capsid inhibitor PF74. Cyclosporine treatment, mutation of the CYPA-binding loop in the capsid, or CYPA knockout eliminated the resistance of SIVcpzPts to PF74 in HeLa cells. These experiments revealed that the antiviral capacity of PF74 is controlled by CYPA in a virus- and cell type-specific manner. Our data indicate that SIVcpz viruses can use infection pathways that escape the antiviral activity of PF74. We further suggest that the antiviral activity of PF74 capsid inhibitors depends on cellular cofactors.IMPORTANCE HIV-1 originated from SIVcpzPtt but not from the related virus SIVcpzPts, and thus, it is important to describe molecular infection by SIVcpzPts in human cells to understand the zoonosis of SIVs. Pharmacological HIV-1 capsid inhibitors (e.g., PF74) bind a capsid groove that is also a binding site for the cellular protein CPSF6. SIVcpzPts was resistant to PF74 in HeLa cells but sensitive in HOS cells, thus indicating cell line-specific resistance. Both SIVcpz viruses showed resistance to PF74 in human PBMCs. Modulating the presence of cyclophilin A or its binding to capsid in HeLa cells overcame SIVcpzPts resistance to PF74. These results indicate that early cytoplasmic infection events of SIVcpzPts may differ between cell types and affect, in an unknown manner, the antiviral activity of capsid inhibitors. Thus, capsid inhibitors depend on the activity or interaction of currently uncharacterized cellular factors.


Assuntos
Fármacos Anti-HIV/farmacologia , Proteínas do Capsídeo/química , Proteínas do Capsídeo/efeitos dos fármacos , Proteínas do Capsídeo/metabolismo , Capsídeo/efeitos dos fármacos , Vírus da Imunodeficiência Símia/efeitos dos fármacos , Fatores de Poliadenilação e Clivagem de mRNA/química , Fatores de Poliadenilação e Clivagem de mRNA/metabolismo , Animais , Sítios de Ligação , Proteínas do Capsídeo/genética , Linhagem Celular , Ciclofilina A/genética , Ciclofilina A/metabolismo , Técnicas de Inativação de Genes , Células HEK293 , HIV-1 , Células HeLa , Humanos , Indazóis/farmacologia , Indóis/farmacologia , Leucócitos Mononucleares/virologia , Macrófagos/virologia , Modelos Moleculares , Pan troglodytes/virologia , Fenilalanina/análogos & derivados , Fenilalanina/farmacologia , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Piridinas/farmacologia , Alinhamento de Sequência , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/química , Vírus da Imunodeficiência Símia/genética , Zoonoses , Fatores de Poliadenilação e Clivagem de mRNA/genética
5.
J Virol ; 92(6)2018 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-29263270

RESUMO

Members of the apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like (APOBEC3 [A3]) family of DNA cytidine deaminases are intrinsic restriction factors against retroviruses. In felids such as the domestic cat (Felis catus), the A3 genes encode the A3Z2, A3Z3, and A3Z2Z3 antiviral cytidine deaminases. Only A3Z3 and A3Z2Z3 inhibit viral infectivity factor (Vif)-deficient feline immunodeficiency virus (FIV). The FIV Vif protein interacts with Cullin (CUL), Elongin B (ELOB), and Elongin C (ELOC) to form an E3 ubiquitination complex to induce the degradation of feline A3s. However, the functional domains in FIV Vif for the interaction with Cullin are poorly understood. Here, we found that the expression of dominant negative CUL5 prevented the degradation of feline A3s by FIV Vif, while dominant negative CUL2 had no influence on the degradation of A3. In coimmunoprecipitation assays, FIV Vif bound to CUL5 but not CUL2. To identify the CUL5 interaction site in FIV Vif, the conserved amino acids from positions 47 to 160 of FIV Vif were mutated, but these mutations did not impair the binding of Vif to CUL5. By focusing on a potential zinc-binding motif (K175-C161-C184-C187) of FIV Vif, we found a conserved hydrophobic region (174IR175) that is important for the CUL5 interaction. Mutation of this region also impaired the FIV Vif-induced degradation of feline A3s. Based on a structural model of the FIV Vif-CUL5 interaction, the 52LW53 region in CUL5 was identified as mediating binding to FIV Vif. By comparing our results to the human immunodeficiency virus type 1 (HIV-1) Vif-CUL5 interaction surface (120IR121, a hydrophobic region that is localized in the zinc-binding motif), we suggest that the CUL5 interaction surface in the diverse HIV-1 and FIV Vifs is evolutionarily conserved, indicating a strong structural constraint. However, the FIV Vif-CUL5 interaction is zinc independent, which contrasts with the zinc dependence of HIV-1 Vif.IMPORTANCE Feline immunodeficiency virus (FIV), which is similar to human immunodeficiency virus type 1 (HIV-1), replicates in its natural host in T cells and macrophages that express the antiviral restriction factor APOBEC3 (A3). To escape A3s, FIV and HIV induce the degradation of these proteins by building a ubiquitin ligase complex using the viral protein Vif to connect to cellular proteins, including Cullin 5. Here, we identified the protein residues that regulate this interaction in FIV Vif and Cullin 5. While our structural model suggests that the diverse FIV and HIV-1 Vifs use conserved residues for Cullin 5 binding, FIV Vif binds Cullin 5 independently of zinc, in contrast to HIV-1 Vif.


Assuntos
Proteínas Culina , HIV-1 , Vírus da Imunodeficiência Felina , Mutação de Sentido Incorreto , Produtos do Gene vif do Vírus da Imunodeficiência Humana , Substituição de Aminoácidos , Animais , Gatos , Linhagem Celular , Proteínas Culina/química , Proteínas Culina/genética , Proteínas Culina/metabolismo , HIV-1/química , HIV-1/genética , HIV-1/metabolismo , Humanos , Interações Hidrofóbicas e Hidrofílicas , Vírus da Imunodeficiência Felina/química , Vírus da Imunodeficiência Felina/genética , Vírus da Imunodeficiência Felina/metabolismo , Ligação Proteica , Dedos de Zinco , Produtos do Gene vif do Vírus da Imunodeficiência Humana/química , Produtos do Gene vif do Vírus da Imunodeficiência Humana/genética , Produtos do Gene vif do Vírus da Imunodeficiência Humana/metabolismo
6.
PLoS Pathog ; 13(12): e1006746, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29267382

RESUMO

APOBEC3s (A3s) are potent restriction factors of human immunodeficiency virus type 1/simian immunodeficiency viruses (HIV-1/SIV), and can repress cross-species transmissions of lentiviruses. HIV-1 originated from a zoonotic infection of SIV of chimpanzee (SIVcpz) to humans. However, the impact of human A3s on the replication of SIVcpz remains unclear. By using novel SIVcpz reporter viruses, we identified that human APOBEC3B (A3B) and APOBEC3H (A3H) haplotype II strongly reduced the infectivity of SIVcpz, because both of them are resistant to SIVcpz Vifs. We further demonstrated that human A3H inhibited SIVcpz by deaminase dependent as well independent mechanisms. In addition, other stably expressed human A3H haplotypes and splice variants showed strong antiviral activity against SIVcpz. Moreover, most SIV and HIV lineage Vif proteins could degrade chimpanzee A3H, but no Vifs from SIVcpz and SIV of gorilla (SIVgor) lineages antagonized human A3H haplotype II. Expression of human A3H hapII in human T cells efficiently blocked the spreading replication of SIVcpz. The spreading replication of SIVcpz was also restricted by stable A3H in human PBMCs. Thus, we speculate that stably expressed human A3H protects humans against the cross-species transmission of SIVcpz and that SIVcpz spillover to humans may have started in individuals that harbor haplotypes of unstable A3H proteins.


Assuntos
Aminoidrolases/metabolismo , Transmissão de Doença Infecciosa , Síndrome de Imunodeficiência Adquirida dos Símios/transmissão , Vírus da Imunodeficiência Símia , Zoonoses , Animais , Humanos , Pan troglodytes
7.
J Stroke Cerebrovasc Dis ; 28(3): 821-829, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30558860

RESUMO

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the authors as it contains erroneous experimental results, pictures, discussions and conclusions related to IL-1ß and TNF-α. The authors were unable to repeat the experimental results of IL-1ß and TNF-α in the subsequent 2 repeated experiments. We apologise and inform the readers of the journal that the conclusions of the manuscript are invalid.


Assuntos
Encéfalo/metabolismo , Hemorragia Cerebral/metabolismo , Mediadores da Inflamação/metabolismo , NF-kappa B/metabolismo , Animais , Apoptose , Encéfalo/patologia , Caspase 3/metabolismo , Hemorragia Cerebral/patologia , Modelos Animais de Doenças , Interleucina-1beta/metabolismo , Masculino , Subunidade p50 de NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-rel/metabolismo , Ratos Wistar , Fatores de Tempo , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
8.
J Virol ; 90(23): 10545-10557, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27630243

RESUMO

Feline immunodeficiency virus (FIV) Vif protein counteracts feline APOBEC3s (FcaA3s) restriction factors by inducing their proteasomal degradation. The functional domains in FIV Vif for interaction with FcaA3s are poorly understood. Here, we have identified several motifs in FIV Vif that are important for selective degradation of different FcaA3s. Cats (Felis catus) express three types of A3s: single-domain A3Z2, single-domain A3Z3, and double-domain A3Z2Z3. We proposed that FIV Vif would selectively interact with the Z2 and the Z3 A3s. Indeed, we identified two N-terminal Vif motifs (12LF13 and 18GG19) that specifically interacted with the FcaA3Z2 protein but not with A3Z3. In contrast, the exclusive degradation of FcaA3Z3 was regulated by a region of three residues (M24, L25, and I27). Only a FIV Vif carrying a combination of mutations from both interaction sites lost the capacity to degrade and counteract FcaA3Z2Z3. However, alterations in the specific A3s interaction sites did not affect the cellular localization of the FIV Vif protein and binding to feline A3s. Pulldown experiments demonstrated that the A3 binding region localized to FIV Vif residues 50 to 80, outside the specific A3 interaction domain. Finally, we found that the Vif sites specific to individual A3s are conserved in several FIV lineages of domestic cat and nondomestic cats, while being absent in the FIV Vif of pumas. Our data support a complex model of multiple Vif-A3 interactions in which the specific region for selective A3 counteraction is discrete from a general A3 binding domain. IMPORTANCE: Both human immunodeficiency virus (HIV) and feline immunodeficiency virus (FIV) Vif proteins counteract their host's APOBEC3 restriction factors. However, these two Vif proteins have limited sequence homology. The molecular interaction between FIV Vif and feline APOBEC3s are not well understood. Here, we identified N-terminal FIV Vif sites that regulate the selective interaction of Vif with either feline APOBEC3Z2 or APOBEC3Z3. These specific Vif sites are conserved in several FIV lineages of domestic cat and nondomestic cats, while being absent in FIV Vif from puma. Our findings provide important insights for future experiments describing the FIV Vif interaction with feline APOBEC3s and also indicate that the conserved feline APOBEC3s interaction sites of FIV Vif allow FIV transmissions in Felidae.


Assuntos
Citidina Desaminase/metabolismo , Produtos do Gene vif/metabolismo , Vírus da Imunodeficiência Felina/metabolismo , Sequência de Aminoácidos , Animais , Gatos/virologia , Linhagem Celular , Citidina Desaminase/química , Citidina Desaminase/genética , Produtos do Gene vif/química , Produtos do Gene vif/genética , Genes Virais , Células HEK293 , Interações Hospedeiro-Patógeno , Humanos , Vírus da Imunodeficiência Felina/classificação , Vírus da Imunodeficiência Felina/genética , Leões/virologia , Mutação , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Proteólise , Homologia de Sequência de Aminoácidos , Especificidade da Espécie
9.
J Virol ; 90(4): 1824-38, 2016 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-26637458

RESUMO

UNLABELLED: Gag intracellular assembly and export are very important processes for lentiviruses replication. Previous studies have demonstrated that equine infectious anemia virus (EIAV) matrix (MA) possesses distinct phosphoinositide affinity compared with HIV-1 MA and that phosphoinositide-mediated targeting to peripheral and internal membranes is a critical factor in EIAV assembly and release. In this study, we compared the cellular assembly sites of EIAV and HIV-1. We observed that the assembly of EIAV particles occurred on interior cellular membranes, while HIV-1 was targeted to the plasma membrane (PM) for assembly. Then, we determined that W7 and K9 in the EIAV MA N terminus were essential for Gag assembly and release but did not affect the cellular distribution of Gag. The replacement of EIAV MA with HIV-1 MA directed chimeric Gag to the PM but severely impaired Gag release. MA structural analysis indicated that the EIAV and HIV-1 MAs had similar spatial structures but that helix 1 of the EIAV MA was closer to loop 2. Further investigation indicated that EIAV Gag accumulated in the trans-Golgi network (TGN) but not the early and late endosomes. The 9 N-terminal amino acids of EIAV MA harbored the signal that directed Gag to the TGN membrane system. Additionally, we demonstrated that EIAV particles were transported to the extracellular space by the cellular vesicle system. This type of EIAV export was not associated with multivesicular bodies or microtubule depolymerization but could be inhibited by the actin-depolymerizing drug cytochalasin D, suggesting that dynamic actin depolymerization may be associated with EIAV production. IMPORTANCE: In previous studies, EIAV Gag was reported to localize to both the cell interior and the plasma membrane. Here, we demonstrate that EIAV likely uses the TGN as the assembly site in contrast to HIV-1, which is targeted to the PM for assembly. These distinct assembly features are determined by the MA domain. We also identified two sites in the N terminus of EIAV MA that were important for Gag assembly and release. Furthermore, the observation of EIAV transport by cellular vesicles but not by multivesicular bodies sheds light on the mechanisms underlying EIAV cellular replication.


Assuntos
Vesículas Citoplasmáticas/metabolismo , Produtos do Gene gag/metabolismo , Vírus da Anemia Infecciosa Equina/fisiologia , Proteínas da Matriz Viral/metabolismo , Montagem de Vírus , Rede trans-Golgi/metabolismo , HIV-1/fisiologia , Humanos , Transporte Proteico
10.
J Virol ; 90(22): 10193-10208, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27581978

RESUMO

Lentiviruses have evolved the Vif protein to counteract APOBEC3 (A3) restriction factors by targeting them for proteasomal degradation. Previous studies have identified important residues in the interface of human immunodeficiency virus type 1 (HIV-1) Vif and human APOBEC3C (hA3C) or human APOBEC3F (hA3F). However, the interaction between primate A3C proteins and HIV-1 Vif or natural HIV-1 Vif variants is still poorly understood. Here, we report that HIV-1 Vif is inactive against A3Cs of rhesus macaques (rhA3C), sooty mangabey monkeys (smmA3C), and African green monkeys (agmA3C), while HIV-2, African green monkey simian immunodeficiency virus (SIVagm), and SIVmac Vif proteins efficiently mediate the depletion of all tested A3Cs. We identified that residues N/H130 and Q133 in rhA3C and smmA3C are determinants for this HIV-1 Vif-triggered counteraction. We also found that the HIV-1 Vif interaction sites in helix 4 of hA3C and hA3F differ. Vif alleles from diverse HIV-1 subtypes were tested for degradation activities related to hA3C. The subtype F-1 Vif was identified to be inactive for degradation of hA3C and hA3F. The residues that determined F-1 Vif inactivity in the degradation of A3C/A3F were located in the C-terminal region (K167 and D182). Structural analysis of F-1 Vif revealed that impairing the internal salt bridge of E171-K167 restored reduction capacities to A3C/A3F. Furthermore, we found that D101 could also form an internal interaction with K167. Replacing D101 with glycine and R167 with lysine in NL4-3 Vif impaired its counteractivity to A3F and A3C. This finding indicates that internal interactions outside the A3 binding region in HIV-1 Vif influence the capacity to induce degradation of A3C/A3F. IMPORTANCE: The APOBEC3 restriction factors can serve as potential barriers to lentiviral cross-species transmissions. Vif proteins from lentiviruses counteract APOBEC3 by proteasomal degradation. In this study, we found that monkey-derived A3C, rhA3C and smmA3C, were resistant to HIV-1 Vif. This was determined by A3C residues N/H130 and Q133. However, HIV-2, SIVagm, and SIVmac Vif proteins were found to be able to mediate the depletion of all tested primate A3C proteins. In addition, we identified a natural HIV-1 Vif (F-1 Vif) that was inactive in the degradation of hA3C/hA3F. Here, we provide for the first time a model that explains how an internal salt bridge of E171-K167-D101 influences Vif-mediated degradation of hA3C/hA3F. This finding provides a novel way to develop HIV-1 inhibitors by targeting the internal interactions of the Vif protein.


Assuntos
Citidina Desaminase/metabolismo , Produtos do Gene vif/metabolismo , HIV-1/metabolismo , Vírus da Imunodeficiência Símia/metabolismo , Produtos do Gene vif do Vírus da Imunodeficiência Humana/metabolismo , Animais , Sítios de Ligação , Linhagem Celular , Células HEK293 , Infecções por HIV/virologia , HIV-2/metabolismo , Humanos , Lentivirus/metabolismo , Macaca mulatta , Ligação Proteica/fisiologia
12.
Retrovirology ; 13(1): 46, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27368163

RESUMO

BACKGROUND: Feline immunodeficiency virus (FIV) is a global pathogen of Felidae species and a model system for Human immunodeficiency virus (HIV)-induced AIDS. In felids such as the domestic cat (Felis catus), APOBEC3 (A3) genes encode for single-domain A3Z2s, A3Z3 and double-domain A3Z2Z3 anti-viral cytidine deaminases. The feline A3Z2Z3 is expressed following read-through transcription and alternative splicing, introducing a previously untranslated exon in frame, encoding a domain insertion called linker. Only A3Z3 and A3Z2Z3 inhibit Vif-deficient FIV. Feline A3s also are restriction factors for HIV and Simian immunodeficiency viruses (SIV). Surprisingly, HIV-2/SIV Vifs can counteract feline A3Z2Z3. RESULTS: To identify residues in feline A3s that Vifs need for interaction and degradation, chimeric human-feline A3s were tested. Here we describe the molecular direct interaction of feline A3s with Vif proteins from cat FIV and present the first structural A3 model locating these interaction regions. In the Z3 domain we have identified residues involved in binding of FIV Vif, and their mutation blocked Vif-induced A3Z3 degradation. We further identified additional essential residues for FIV Vif interaction in the A3Z2 domain, allowing the generation of FIV Vif resistant A3Z2Z3. Mutated feline A3s also showed resistance to the Vif of a lion-specific FIV, indicating an evolutionary conserved Vif-A3 binding. Comparative modelling of feline A3Z2Z3 suggests that the residues interacting with FIV Vif have, unlike Vif-interacting residues in human A3s, a unique location at the domain interface of Z2 and Z3 and that the linker forms a homeobox-like domain protruding of the Z2Z3 core. HIV-2/SIV Vifs efficiently degrade feline A3Z2Z3 by possible targeting the linker stretch connecting both Z-domains. CONCLUSIONS: Here we identified in feline A3s residues important for binding of FIV Vif and a unique protein domain insertion (linker). To understand Vif evolution, a structural model of the feline A3 was developed. Our results show that HIV Vif binds human A3s differently than FIV Vif feline A3s. The linker insertion is suggested to form a homeo-box domain, which is unique to A3s of cats and related species, and not found in human and mouse A3s. Together, these findings indicate a specific and different A3 evolution in cats and human.


Assuntos
Citidina Desaminase/química , Citidina Desaminase/metabolismo , Produtos do Gene vif/metabolismo , HIV-1/metabolismo , Vírus da Imunodeficiência Felina/metabolismo , Animais , Gatos , Linhagem Celular , Citidina Desaminase/genética , Evolução Molecular , Produtos do Gene vif/genética , Genes Homeobox , HIV-1/genética , Humanos , Vírus da Imunodeficiência Felina/genética , Modelos Moleculares , Proteínas Recombinantes de Fusão/metabolismo
13.
J Gen Virol ; 97(9): 2421-2426, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27411804

RESUMO

Rev, an important accessory protein of equine infectious anaemia virus (EIAV), induces the nuclear export of incompletely spliced viral mRNAs. Rev is translated from the tat-rev mRNA through leaky scanning of the tat CUG. In this study, the function of the Kozak sequence at the beginning of the rev ORF was investigated. Deletion or attenuation of the Kozak sequence resulted in expression of an N-terminal 11 aa-truncated Rev in addition to WT Rev. Truncated Rev displayed weaker promotion of Gag expression and processing than WT Rev. Furthermore, EIAV rescued from an infectious molecular clone (pEIAVUK3) with Kozak attenuation exhibited decreased viral replication in host cells in vitro. These results provide a new understanding of the relationship between EIAV Rev expression and viral replication.


Assuntos
Regulação Viral da Expressão Gênica , Produtos do Gene rev/biossíntese , Produtos do Gene tat/biossíntese , Vírus da Anemia Infecciosa Equina/genética , Biossíntese de Proteínas , RNA Mensageiro/metabolismo , Replicação Viral , Linhagem Celular , Produtos do Gene rev/genética , Humanos
14.
J Neuroinflammation ; 12: 53, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25889503

RESUMO

BACKGROUND: Nuclear factor-κB (NF-κB) plays an important role in the inflammatory response after intracerebral hemorrhage (ICH). We therefore proposed that NF-κB activation in perihematomal brain tissue might correlate with clinical outcome in patients with ICH. To confirm this, we studied clinical data of 45 patients with ICH and NF-κB activation in perihematomal brain tissue and analyzed predictors of clinical outcome as well as the predictive value of NF-κB activation. METHODS: Forty-five patients with spontaneous basal ganglia hemorrhage were prospectively investigated. The clinical data were collected, which include demographics, alcohol and tobacco abuse, stroke risk factors, neuroimaging variables at presentation, Glasgow Coma Scale (GCS) at admission, number of days in hospital, mechanical ventilation, pneumonia, and outcome. Clinical outcome was assessed by the modified Rankin Scale at 6 months after ICH. Perihematomal brain tissue was collected, and NF-κB activation was detected using immunohistochemistry. Univariate analysis and multivariate logistic regression analysis were performed to determine predictors of the poor outcome. RESULTS: Immunohistochemical detection showed that NF-κB p65 was expressed in the nuclei of neurons and glial cells in all patients. The number of nuclear NF-κB p65-positive cells was 54 ± 21. Six months after ICH, 18 (40%) patients achieved a favorable functional outcome (mRS ≤ 3) while 27 (60%) had a poor functional outcome (mRS 4 to 6). In univariate analysis, predictors of poor functional outcome were lower GCS score on admission (P = 0.004), larger hematoma volume (P = 0.004), intraventricular extension (P = 0.047), midline shift (P = 0.005), NF-κB activation (P < 0.0001), mechanical ventilation (P = 0.018), and co-morbidity with pneumonia (P = 0.002). In multivariate logistic regression analysis, NF-κB activation was the only independent predictor of poor outcome at 6 months after ICH. CONCLUSIONS: NF-κB activation is closely related to clinical outcome 6 months after ICH in humans. Therefore, it could be useful to predict prognosis of ICH accurately and should be further evaluated as a target for therapeutic strategies of ICH in the future.


Assuntos
Gânglios da Base/metabolismo , Hemorragia Cerebral/complicações , Hematoma/etiologia , Hematoma/patologia , NF-kappa B/metabolismo , Adulto , Idoso , Análise de Variância , Hemorragia Cerebral/patologia , Feminino , Escala de Coma de Glasgow , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/metabolismo , Análise de Regressão , Estudos Retrospectivos
15.
Neurol Sci ; 35(7): 1097-102, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24510152

RESUMO

Nuclear factor-κB (NF-κB) plays an important role in secondary damage after intracerebral hemorrhage (ICH). We explored NF-κB activation and the relationship between NF-κB and cell death in the perihematomal brain tissue of patients after ICH. According to the interval between onset of hemorrhage and specimen collection, 53 cases of patients with basal ganglia hemorrhage were divided into six experimental groups: 0-6, 7-12, 13-24, 25-48, 49-96, and >96 h group. Brain tissues of the experimental groups and control group were collected. IL-1ß, TNF-α, and NF-κB p65 expressions at the protein level were detected by immunohistochemistry. Cell death was detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) assay. All of the detection items of immunohistochemistry and TUNEL showed significant differences between the experimental groups and control group. At the protein level, nuclear NF-κB p65, IL-1ß, and TNF-α achieved maximum values at 13-48, 0-24, and 13-48 h, respectively. Maximum cell death was reached at 13-48 h. NF-κB activation increased dramatically in perihematomal brain tissue after ICH. NF-κB activation was closely related with cell death and had an important function in secondary brain damage after ICH in patients.


Assuntos
Hemorragia Cerebral/enzimologia , Hemorragia Cerebral/patologia , NF-kappa B/metabolismo , Adulto , Idoso , Morte Celular/fisiologia , Hemorragia Cerebral/complicações , Feminino , Regulação da Expressão Gênica , Hematoma/etiologia , Humanos , Marcação In Situ das Extremidades Cortadas , Interleucina-1beta/metabolismo , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Fator de Necrose Tumoral alfa/metabolismo
16.
Zhonghua Yi Xue Za Zhi ; 94(9): 692-4, 2014 Mar 11.
Artigo em Zh | MEDLINE | ID: mdl-24842211

RESUMO

OBJECTIVE: To explore the clinical characteristics, efficacy and prognosis of primary extradural meningiomas (PEMs) in head. METHODS: A total of 19 treated surgically case of PEMs at Qilu Hospital, Shandong University between May 1994 and December 2012 were analyzed retrospectively with respects to their demographic features, presenting symptoms & duration, tumor location & type, imaging features, surgical results, pathological grade, histological subtype and follow-up outcomes. RESULTS: PEMs in head accounted for 1.2% of all meningiomas in this group. The male-to-female ratio was 1: 0.7. The mean age was 36.6 years with a bimodal distribution of age. The common presenting symptoms included nasal obstruction and a painless and gradually expanding mass in the region of lesion. The average duration of symptom was 3.07 years. The skull convexities, paranasal sinuses and nasal cavity, orbit and epidural space were common tumor sites. The most common type was typeII. The rate of total tumor removal was 100%. And no perioperative mortality occurred in this series. Benign and atypical meningiomas accounted for 94.7% and 6.3% respectively. Meningothelial and psammomatous meningiomas were common histopathological subtypes. There was one case of tumoral recurrence. And no mortality was reported during a mean follow-up period of 2.43 (0.25-8.5) years. CONCLUSION: PEMs in head have some marked clinical characteristics compared with primary intradural meningiomas. Total tumor removal together with a wide excision of all involved tissue followed by the reconstruction of tissue defects is the best surgical option. The prognosis is excellent in most cases after complete resection.


Assuntos
Neoplasias Meníngeas , Meningioma , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Neoplasias Meníngeas/diagnóstico , Neoplasias Meníngeas/terapia , Meningioma/diagnóstico , Meningioma/terapia , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
17.
Cell Rep Med ; 5(6): 101583, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38781962

RESUMO

Little is known about the effect of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2 or SARS2) vaccine breakthrough infections (BTIs) on the magnitude and breadth of the T cell repertoire after exposure to different variants. We studied samples from individuals who experienced symptomatic BTIs during Delta or Omicron waves. In the pre-BTI samples, 30% of the donors exhibited substantial immune memory against non-S (spike) SARS2 antigens, consistent with previous undiagnosed asymptomatic SARS2 infections. Following symptomatic BTI, we observed (1) enhanced S-specific CD4 and CD8 T cell responses in donors without previous asymptomatic infection, (2) expansion of CD4 and CD8 T cell responses to non-S targets (M, N, and nsps) independent of SARS2 variant, and (3) generation of novel epitopes recognizing variant-specific mutations. These variant-specific T cell responses accounted for 9%-15% of the total epitope repertoire. Overall, BTIs boost vaccine-induced immune responses by increasing the magnitude and by broadening the repertoire of T cell antigens and epitopes recognized.


Assuntos
Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Vacinas contra COVID-19 , COVID-19 , Epitopos de Linfócito T , SARS-CoV-2 , Humanos , SARS-CoV-2/imunologia , COVID-19/imunologia , COVID-19/virologia , Epitopos de Linfócito T/imunologia , Epitopos de Linfócito T/genética , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD4-Positivos/imunologia , Vacinas contra COVID-19/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Memória Imunológica/imunologia , Feminino , Adulto , Masculino , Mutação , Pessoa de Meia-Idade , Linfócitos T/imunologia , Infecções Irruptivas
18.
Zhonghua Yi Xue Za Zhi ; 93(23): 1788-90, 2013 Jun 18.
Artigo em Zh | MEDLINE | ID: mdl-24124710

RESUMO

OBJECTIVE: To explore the clinical application of intracranial pressure (ICP) monitoring and its prognostic correlation in patients with severe craniocerebral injury. METHODS: A total of 216 severe craniocerebral injury patients with scores of Glasgow coma scale 3-8 underwent craniotomy at Affiliated Qilu Hospital, Shandong University.And 168 cases of ICP monitoring were divided into 3 treatment groups and another 48 cases without ICP monitoring selected as the control group.According to ICP, stepwise treatment was administered to control the level of ICP and maintain the cerebral perfusion pressure to analyze the relationship between ICP monitoring and prognosis. RESULTS: As compared with the control group, there were significant decreases of disability and mortality rate for patients with ICP monitoring (A, B, C group). Especially group C had a better prognosis than the other groups for statistical significance.In addition, the dose and duration of mannitol of group A, B or C were significantly lower than those of the control group (P < 0.05). CONCLUSION: The application of ICP monitoring is capable of reducing mortality, improving prognosis and enhancing success rate of treating severe craniocerebral injury.


Assuntos
Traumatismos Craniocerebrais/diagnóstico , Pressão Intracraniana , Monitorização Fisiológica , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Traumatismos Craniocerebrais/fisiopatologia , Traumatismos Craniocerebrais/cirurgia , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Prognóstico , Adulto Jovem
19.
J Genet Genomics ; 50(12): 934-947, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37865193

RESUMO

Since the outbreak of coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in late 2019, the virus has rapidly spread worldwide. This has led to an unprecedented global pandemic, marked by millions of COVID-19 cases and a significant number of fatalities. Over a relatively short period, several different vaccine platforms are developed and deployed for use globally to curb the pandemic. However, the genome of SARS-CoV-2 continuously undergoes mutation and/or recombination, resulting in the emergence of several variants of concern (VOC). These VOCs can elevate viral transmission and evade the neutralizing antibodies induced by vaccines, leading to reinfections. Understanding the impact of the SARS-CoV-2 genomic mutation on viral pathogenesis and immune escape is crucial for assessing the threat of new variants to public health. This review focuses on the emergence and pathogenesis of VOC, with particular emphasis on their evasion of neutralizing antibodies. Furthermore, the memory B cell, CD4+, and CD8+ T cell memory induced by different COVID-19 vaccines or infections are discussed, along with how these cells recognize VOC. This review summarizes the current knowledge on adaptive immunology regarding SARS-CoV-2 infection and vaccines. Such knowledge may also be applied to vaccine design for other pathogens.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Vacinas contra COVID-19/genética , Imunidade Celular , Anticorpos Neutralizantes
20.
Surg Infect (Larchmt) ; 24(1): 66-74, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36580653

RESUMO

Objectives: Intra-cranial infection is the most serious complication after ventriculoperitoneal shunt (VPS). There were differences in clinical characteristics between early (occurs within one month after VPS, the early group) and delayed (occurs 1 month or more after VPS, the delayed group) infections. The aim of this study is to clarify the differences between the two groups. Patients and Methods: All cases diagnosed as intracranial infection after VPS between September 2017 and December 2021 were collected. Clinical data were reviewed and analyzed retrospectively. Results: Nineteen cases met the inclusion criteria, including 12 cases in the early group and seven cases in the delayed group. There were no significant differences between the two groups in gender, age, and etiology of hydrocephalus. Cases in the early group usually had fever with worsening consciousness (11; 91.7%), which was caused by surgical operations (10; 83.3%) with gram-positive coccis infection (9; 75.0%), whereas those in the delayed group had abdominal pain (5; 71.4%), caused by abdominal factor (7; 100%) with gram-negative bacilli infection (6; 85.7%). There were differences in symptoms (p < 0.01), causes of infection (p < 0.001), and pathogens (p < 0.05). Shunt removal was performed for all 19 cases. After the infection was controlled, eight cases received VPS again, and no re-infection occurred after a follow-up of four to 22 months. Conclusions: It is suggested in this study that there were differences between the two groups in terms of etiology, symptoms, and pathogens. The results can provide theoretical basis for prevention, early diagnosis, and reasonable treatment of infection after VPS.


Assuntos
Hidrocefalia , Derivação Ventriculoperitoneal , Humanos , Adulto , Estudos Retrospectivos , Derivação Ventriculoperitoneal/efeitos adversos , Derivação Ventriculoperitoneal/métodos , Hidrocefalia/cirurgia , Hidrocefalia/etiologia , Abdome/cirurgia
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