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1.
PLoS Pathog ; 17(7): e1009668, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34280241

RESUMO

SARS-CoV-2 infection presents clinical manifestations ranging from asymptomatic to fatal respiratory failure. Despite the induction of functional SARS-CoV-2-specific CD8+ T-cell responses in convalescent individuals, the role of virus-specific CD8+ T-cell responses in the control of SARS-CoV-2 replication remains unknown. In the present study, we show that subacute SARS-CoV-2 replication can be controlled in the absence of CD8+ T cells in cynomolgus macaques. Eight macaques were intranasally inoculated with 105 or 106 TCID50 of SARS-CoV-2, and three of the eight macaques were treated with a monoclonal anti-CD8 antibody on days 5 and 7 post-infection. In these three macaques, CD8+ T cells were undetectable on day 7 and thereafter, while virus-specific CD8+ T-cell responses were induced in the remaining five untreated animals. Viral RNA was detected in nasopharyngeal swabs for 10-17 days post-infection in all macaques, and the kinetics of viral RNA levels in pharyngeal swabs and plasma neutralizing antibody titers were comparable between the anti-CD8 antibody treated and untreated animals. SARS-CoV-2 RNA was detected in the pharyngeal mucosa and/or retropharyngeal lymph node obtained at necropsy on day 21 in two of the untreated group but undetectable in all macaques treated with anti-CD8 antibody. CD8+ T-cell responses may contribute to viral control in SARS-CoV-2 infection, but our results indicate possible containment of subacute viral replication in the absence of CD8+ T cells, implying that CD8+ T-cell dysfunction may not solely lead to viral control failure.


Assuntos
Linfócitos T CD8-Positivos/imunologia , COVID-19/veterinária , Macaca fascicularis/imunologia , Macaca fascicularis/virologia , Doenças dos Macacos/imunologia , Doenças dos Macacos/virologia , SARS-CoV-2/imunologia , SARS-CoV-2/fisiologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , COVID-19/imunologia , COVID-19/virologia , Modelos Animais de Doenças , Feminino , Humanos , Cinética , Depleção Linfocítica/veterinária , Masculino , RNA Viral/genética , RNA Viral/metabolismo , SARS-CoV-2/genética , Replicação Viral/imunologia
2.
Front Cell Infect Microbiol ; 11: 646467, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34084754

RESUMO

HIV-1 infected individuals under antiretroviral therapy can control viremia but often develop non-AIDS diseases such as cardiovascular and metabolic disorders. Gut microbiome dysbiosis has been indicated to be associated with progression of these diseases. Analyses of gut/fecal microbiome in individual regions are important for our understanding of pathogenesis in HIV-1 infections. However, data on gut/fecal microbiome has not yet been accumulated in West Africa. In the present study, we examined fecal microbiome compositions in HIV-1 infected adults in Ghana, where approximately two-thirds of infected adults are females. In a cross-sectional case-control study, age- and gender-matched HIV-1 infected adults (HIV+; n = 55) and seronegative controls (HIV-; n = 55) were enrolled. Alpha diversity of fecal microbiome in HIV+ was significantly reduced compared to HIV- and associated with CD4 counts. HIV+ showed reduction in varieties of bacteria including Faecalibacterium, the most abundant in seronegative controls, but enrichment of Proteobacteria. Ghanaian HIV+ exhibited enrichment of Dorea and Blautia; bacteria groups whose depletion has been reported in HIV-1 infected individuals in several other cohorts. Furthermore, HIV+ in our cohort exhibited a depletion of Prevotella, a genus whose enrichment has recently been shown in men having sex with men (MSM) regardless of HIV-1 status. The present study revealed the characteristics of dysbiotic fecal microbiome in HIV-1 infected adults in Ghana, a representative of West African populations.


Assuntos
Infecções por HIV , HIV-1 , Microbiota , Adulto , Estudos de Casos e Controles , Estudos Transversais , Disbiose , Feminino , Gana , Humanos , Masculino
3.
HLA ; 98(1): 37-42, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33734601

RESUMO

HLA-A, -C, -B, and -DRB1 genotypes were analyzed in 178 Japanese COVID-19 patients to investigate the association of HLA with severe COVID-19. Analysis of 32 common HLA alleles at four loci revealed a significant association between HLA-DRB1*09:01 and severe COVID-19 (odds ratio [OR], 3.62; 95% CI, 1.57-8.35; p = 0.00251 [permutation p value = 0.0418]) when age, sex, and other common HLA alleles at the DRB1 locus were adjusted. The DRB1*09:01 allele was more significantly associated with risk for severe COVID-19 compared to preexisting medical conditions such as hypertension, diabetes, and cardiovascular diseases. These results indicate a potential role for HLA in predisposition to severe COVID-19.


Assuntos
COVID-19 , Cadeias HLA-DRB1 , Alelos , COVID-19/diagnóstico , COVID-19/genética , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Cadeias HLA-DRB1/genética , Humanos
4.
Int Immunol ; 33(4): 241-247, 2021 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-33538817

RESUMO

An expanded myeloid cell compartment is a hallmark of severe coronavirus disease 2019 (COVID-19). However, data regarding myeloid cell expansion have been collected in Europe, where the mortality rate by COVID-19 is greater than those in other regions including Japan. Thus, characteristics of COVID-19-induced myeloid cell subsets remain largely unknown in the regions with low mortality rates. Here, we analyzed cellular dynamics of myeloid-derived suppressor cell (MDSC) subsets and examined whether any of them correlate with disease severity and prognosis, using blood samples from Japanese COVID-19 patients. We observed that polymorphonuclear (PMN)-MDSCs, but not other MDSC subsets, transiently expanded in severe cases but not in mild or moderate cases. Contrary to previous studies in Europe, this subset selectively expanded in survivors of severe cases and subsided before discharge, but such transient expansion was not observed in non-survivors in Japanese cohort. Analysis of plasma cytokine/chemokine levels revealed positive correlation of PMN-MDSC frequencies with IL-8 levels, indicating the involvement of IL-8 on recruitment of PMN-MDSCs to peripheral blood following the onset of severe COVID-19. Our data indicate that transient expansion of the PMN-MDSC subset results in improved clinical outcome. Thus, this myeloid cell subset may be a predictor of prognosis in cases of severe COVID-19 in Japan.


Assuntos
COVID-19/patologia , Interleucina-8/sangue , Células Supressoras Mieloides/imunologia , Neutrófilos/imunologia , SARS-CoV-2/imunologia , Humanos , Interleucina-8/imunologia , Japão , Contagem de Leucócitos , Células Mieloides/imunologia , Ativação de Neutrófilo/imunologia
5.
Jpn J Infect Dis ; 74(1): 42-47, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-32611986

RESUMO

Recent studies have indicated an association between gut microbiome composition and various disorders, including infectious diseases. The composition of the microbiome differs among ethnicities and countries, possibly resulting in diversified interactions between host immunity and the gut microbiome. Characterization of baseline microbiome composition in healthy people is an essential step for better understanding of the biological interactions associated with individual populations. However, data on the gut/fecal microbiome have not been accumulated for individuals in West Africa. In the present study, we examined the fecal microbiome composition in healthy adults in Ghana. Toward this, 16S rRNA gene libraries were prepared using bacterial fractions derived from 55 Ghanaian adults, which were then subjected to next-generation sequencing. The fecal microbiome of the Ghanaian adults was dominated by Firmicutes (Faecalibacterium, Subdoligranulum, and Ruminococcaceae UCG-014), Proteobacteria (Escherichia-Shigella and Klebsiella), and Bacteroidetes (Prevotella 9 and Bacteroides), consistent with previous observations in African cohorts. Further, our analysis revealed differences in microbiome composition and a lower diversity of the fecal microbiome in the Ghanaian cohort compared with those reported in non-African countries. This is the first study to describe substantial fecal microbiome data obtained using high-throughput metagenomic tools on samples derived from a cohort in Ghana. The data may provide a valuable basis for determining the association between the fecal microbiome and progression of various diseases in West African populations.


Assuntos
Fezes/microbiologia , Microbioma Gastrointestinal/genética , Adulto , Bacteroidetes/genética , Estudos Transversais , Feminino , Firmicutes/genética , Gana , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Metagenômica , Microbiota , Pessoa de Meia-Idade , Proteobactérias/genética , RNA Bacteriano/isolamento & purificação , RNA Ribossômico 16S/genética
6.
Sci Rep ; 10(1): 11394, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32647227

RESUMO

Anti-retroviral therapy (ART) can inhibit HIV proliferation but not achieve virus eradication from HIV-infected individuals. Under ART-based HIV control, virus-specific CD8+ T-cell responses are often reduced. Here, we investigated the impact of therapeutic vaccination inducing virus-specific CD8+ T-cell responses under ART on viral control in a macaque AIDS model. Twelve rhesus macaques received ART from week 12 to 32 after simian immunodeficiency virus (SIV) infection. Six of them were vaccinated with Sendai virus vectors expressing SIV Gag and Vif at weeks 26 and 32, and Gag/Vif-specific CD8+ T-cell responses were enhanced and became predominant. All macaques controlled viremia during ART but showed viremia rebound after ART cessation. Analysis of in vitro CD8+ cell ability to suppress replication of autologous lymphocytes-derived SIVs found augmentation of anti-SIV efficacy of CD8+ cells after vaccination. In the vaccinated animals, the anti-SIV efficacy of CD8+ cells at week 34 was correlated positively with Gag-specific CD8+ T-cell frequencies and inversely with rebound viral loads at week 34. These results indicate that Gag-specific CD8+ T-cell induction by therapeutic vaccination can augment anti-virus efficacy of CD8+ cells, which may be insufficient for functional cure but contribute to more stable viral control under ART.


Assuntos
Síndrome de Imunodeficiência Adquirida/terapia , Antirretrovirais/farmacologia , Linfócitos T CD8-Positivos/imunologia , Vacinas contra a SAIDS/administração & dosagem , Síndrome de Imunodeficiência Adquirida dos Símios/terapia , Síndrome de Imunodeficiência Adquirida/imunologia , Síndrome de Imunodeficiência Adquirida/virologia , Animais , Antirretrovirais/uso terapêutico , Linfócitos T CD8-Positivos/efeitos dos fármacos , Modelos Animais de Doenças , Produtos do Gene gag/imunologia , Produtos do Gene vif/imunologia , Humanos , Imunogenicidade da Vacina , Macaca mulatta , Vacinas contra a SAIDS/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/imunologia , Carga Viral/efeitos dos fármacos , Carga Viral/imunologia
7.
Biochem Biophys Res Commun ; 512(2): 213-217, 2019 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-30878187

RESUMO

In human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) infections, host major histocompatibility complex class I (MHC-I) genotypes have a great impact on viral replication and MHC-I-associated viral genome mutations are selected under CD8+ T-cell pressure. Association of MHC-I genotypes with HIV/SIV control has been investigated at MHC-I allele levels but not fully at haplotype levels. We previously established groups of rhesus macaques sharing individual MHC-I haplotypes. In the present study, we compared viral genome diversification after SIV infection in macaques possessing a protective MHC-I haplotype, 90-010-Id, with those possessing a non-protective MHC-I haplotype, 90-010-Ie. These two MHC-I haplotypes are associated with immunodominant CD8+ T-cell responses targeting similar regions of viral Nef antigen. Analyses of viral genome sequences and antigen-specific T-cell responses showed four and two candidates of viral CD8+ T-cell targets associated with 90-010-Id and 90-010-Ie, respectively, in addition to the Nef targets. In these CD8+ T-cell target regions, higher numbers of mutations were detected at the setpoint after SIV infection in macaques possessing 90-010-Id than those possessing 90-010-Ie. These results indicate higher selective pressure on overall CD8+ T-cell targets associated with the protective MHC-I haplotype, suggesting a pattern of HIV/SIV control by multiple target-specific CD8+ T-cell responses.


Assuntos
Linfócitos T CD8-Positivos/virologia , Genes MHC Classe I , Macaca mulatta/virologia , Síndrome de Imunodeficiência Adquirida dos Símios/genética , Vírus da Imunodeficiência Símia/fisiologia , Animais , Linfócitos T CD8-Positivos/metabolismo , Genes nef , Genoma Viral , Haplótipos , Macaca mulatta/genética , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/genética , Replicação Viral
8.
PLoS Pathog ; 13(9): e1006638, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28931083

RESUMO

CD8+ T-cell responses exert strong suppressive pressure on HIV replication and select for viral escape mutations. Some of these major histocompatibility complex class I (MHC-I)-associated mutations result in reduction of in vitro viral replicative capacity. While these mutations can revert after viral transmission to MHC-I-disparate hosts, recent studies have suggested that these MHC-I-associated mutations accumulate in populations and make viruses less pathogenic in vitro. Here, we directly show an increase in the in vivo virulence of an MHC-I-adapted virus serially-passaged through MHC-I-mismatched hosts in a macaque AIDS model despite a reduction in in vitro viral fitness. The first passage simian immunodeficiency virus (1pSIV) obtained 1 year after SIVmac239 infection in a macaque possessing a protective MHC-I haplotype 90-120-Ia was transmitted into 90-120-Ia- macaques, whose plasma 1 year post-infection was transmitted into other 90-120-Ia- macaques to obtain the third passage SIV (3pSIV). Most of the 90-120-Ia-associated mutations selected in 1pSIV did not revert even in 3pSIV. 3pSIV showed lower in vitro viral fitness but induced persistent viremia in 90-120-Ia- macaques. Remarkably, 3pSIV infection in 90-120-Ia+ macaques resulted in significantly higher viral loads and reduced survival compared to wild-type SIVmac239. These results indicate that MHC-I-adapted SIVs serially-transmitted through MHC-I-mismatched hosts can have higher virulence in MHC-I-matched hosts despite their lower in vitro viral fitness. This study suggests that multiply-passaged HIVs could result in loss of HIV-specific CD8+ T cell responses in human populations and the in vivo pathogenic potential of these escaped viruses may be enhanced.


Assuntos
Antígenos de Histocompatibilidade Classe I/genética , Evasão da Resposta Imune/imunologia , Vírus da Imunodeficiência Símia/imunologia , Vírus da Imunodeficiência Símia/patogenicidade , Animais , Linfócitos T CD8-Positivos/imunologia , Evasão da Resposta Imune/genética , Macaca mulatta , Virulência
10.
J Virol ; 90(14): 6276-6290, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27122584

RESUMO

UNLABELLED: Identifying human immunodeficiency virus type 1 (HIV-1) control mechanisms by neutralizing antibodies (NAbs) is critical for anti-HIV-1 strategies. Recent in vivo studies on animals infected with simian immunodeficiency virus (SIV) and related viruses have shown the efficacy of postinfection NAb passive immunization for viremia reduction, and one suggested mechanism is its occurrence through modulation of cellular immune responses. Here, we describe SIV control in macaques showing biphasic CD8(+) cytotoxic T lymphocyte (CTL) responses following acute-phase NAb passive immunization. Analysis of four SIVmac239-infected rhesus macaque pairs matched with major histocompatibility complex class I haplotypes found that counterparts receiving day 7 anti-SIV polyclonal NAb infusion all suppressed viremia for up to 2 years without accumulating viral CTL escape mutations. In the first phase of primary viremia control attainment, CD8(+) cells had high capacities to suppress SIVs carrying CTL escape mutations. Conversely, in the second, sustained phase of SIV control, CTL responses converged on a pattern of immunodominant CTL preservation. During this sustained phase of viral control, SIV epitope-specific CTLs showed retention of phosphorylated extracellular signal-related kinase (ERK)(hi)/phosphorylated AMP-activated protein kinase (AMPK)(lo) subpopulations, implying their correlation with SIV control. The results suggest that virus-specific CTLs functionally boosted by acute-phase NAbs may drive robust AIDS virus control. IMPORTANCE: In early HIV infection, NAb responses are lacking and CTL responses are insufficient, which leads to viral persistence. Hence, it is important to identify immune responses that can successfully control such HIV replication. Here, we show that monkeys receiving NAb passive immunization in early SIV infection strictly control viral replication for years. Passive infusion of NAbs with CTL cross-priming capacity resulted in induction of functionally boosted early CTL responses showing enhanced suppression of CTL escape mutant virus replication. Accordingly, the NAb-infused animals did not show accumulation of viral CTL escape mutations during sustained SIV control, and immunodominant CTL responses were preserved. This early functional augmentation of CTLs by NAbs provides key insights into the design of lasting and viral escape mutation-free protective immunity against HIV-1 infection.


Assuntos
Anticorpos Neutralizantes/uso terapêutico , Anticorpos Antivirais/uso terapêutico , Linfócitos T CD8-Positivos/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/prevenção & controle , Vírus da Imunodeficiência Símia/imunologia , Linfócitos T Citotóxicos/imunologia , Viremia/prevenção & controle , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Humanos , Imunização Passiva , Macaca mulatta , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Viremia/imunologia , Viremia/virologia , Replicação Viral
11.
Expert Rev Vaccines ; 15(1): 119-27, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26512881

RESUMO

Virus-specific CD8(+) T-cell responses play a major role in the control of HIV replication, and induction of HIV-specific T-cell responses is an important strategy for AIDS vaccine development. Optimization of the delivery system and immunogen would be the key for the development of an effective T cell-based AIDS vaccine. Heterologous prime-boost vaccine regimens using multiple viral vectors are a promising protocol for efficient induction of HIV-specific T-cell responses, and the development of a variety of potent viral vectors have been attempted. This review describes the current progress of the development of T cell-based AIDS vaccines using viral vectors, focusing on Sendai virus vectors, whose phase I clinical trials have been performed.


Assuntos
Vacinas contra a AIDS/imunologia , Linfócitos T CD8-Positivos/imunologia , Portadores de Fármacos , Vetores Genéticos , Vírus Sendai/genética , Vacinas contra a AIDS/administração & dosagem , Vacinas contra a AIDS/genética , Vacinas contra a AIDS/isolamento & purificação , Descoberta de Drogas/métodos , Descoberta de Drogas/tendências , Humanos , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/isolamento & purificação
12.
J Virol ; 88(1): 425-33, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24155398

RESUMO

For development of an effective T cell-based AIDS vaccine, it is critical to define the antigens that elicit the most potent responses. Recent studies have suggested that Gag-specific and possibly Vif/Nef-specific CD8(+) T cells can be important in control of the AIDS virus. Here, we tested whether induction of these CD8(+) T cells by prophylactic vaccination can result in control of simian immunodeficiency virus (SIV) replication in Burmese rhesus macaques sharing the major histocompatibility complex class I (MHC-I) haplotype 90-010-Ie associated with dominant Nef-specific CD8(+) T-cell responses. In the first group vaccinated with Gag-expressing vectors (n = 5 animals), three animals that showed efficient Gag-specific CD8(+) T-cell responses in the acute phase postchallenge controlled SIV replication. In the second group vaccinated with Vif- and Nef-expressing vectors (n = 6 animals), three animals that elicited Vif-specific CD8(+) T-cell responses in the acute phase showed SIV control, whereas the remaining three with Nef-specific but not Vif-specific CD8(+) T-cell responses failed to control SIV replication. Analysis of 18 animals, consisting of seven unvaccinated noncontrollers and the 11 vaccinees described above, revealed that the sum of Gag- and Vif-specific CD8(+) T-cell frequencies in the acute phase was inversely correlated with plasma viral loads in the chronic phase. Our results suggest that replication of the AIDS virus can be controlled by vaccine-induced subdominant Gag/Vif epitope-specific CD8(+) T cells, providing a rationale for the induction of Gag- and/or Vif-specific CD8(+) T-cell responses by prophylactic AIDS vaccines.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Produtos do Gene gag/imunologia , Produtos do Gene vif/imunologia , Vírus da Imunodeficiência Símia/fisiologia , Vacinas Virais/imunologia , Replicação Viral/imunologia , Animais , Macaca mulatta , Carga Viral
13.
Microbes Infect ; 15(10-11): 697-707, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23791954

RESUMO

IL-21 signaling is important for T cell and B cell-mediated clearance of chronic viral infections. While non-cognate follicular helper CD4+ T cells (TFH) are indicated to be pivotal in providing IL-21-mediated help to activated B cells within germinal centers, how this signaling may be disrupted in early AIDS virus infection is not clear. In this study, we assessed the lineage and kinetics of peripheral blood IL-21-producing CD4+ T cells in primary simian immunodeficiency virus (SIV) infection of rhesus macaques. After SIV challenge, antigen-nonspecific IL-21 production was observed in Th1, Th2 and Th17 cells with Th1 dominance. While IL-21+ Th2 and IL-21+ Th17 showed variable kinetics, an increase in total IL-21+ CD4+ T cells and IL-21+ Th1 from week 3 to week 8 was observed, preceding plasma SIV-specific IgG development from week 5 to week 12. SIV Gag-specific IL-21+ CD4+ T cells detectable at week 2 were decreased in frequencies at week 5. Results imply that kinetics of IL-21+ CD4+ T cells comprised of multiple lineages, potentially targeted by SIV with a bias of existing frequencies during their precursor stage, associate with availability of cooperative B-cell help provided through a proportionate precursor pool developing into TFH and subsequent anti-SIV antibody responses.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Interleucinas/metabolismo , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia/imunologia , Animais , Macaca mulatta , Subpopulações de Linfócitos T/imunologia , Fatores de Tempo
14.
Front Microbiol ; 2: 267, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22319514

RESUMO

Cytotoxic T lymphocyte (CTL) responses exert a suppressive effect on HIV and simian immunodeficiency virus (SIV) replication. Under the CTL pressure, viral CTL escape mutations are frequently selected with viral fitness costs. Viruses with such CTL escape mutations often need additional viral genome mutations for recovery of viral fitness. Persistent HIV/SIV infection sometimes shows replacement of a CTL escape mutation with an alternative escape mutation toward higher viral fitness. Thus, multiple viral genome changes under CTL pressure are observed in the chronic phase of HIV/SIV infection. HIV/SIV transmission to HLA/MHC-mismatched hosts drives further viral genome changes including additional CTL escape mutations and reversions under different CTL pressure. Understanding of viral structure/function and host CTL responses would contribute to prediction of HIV evolution and control of HIV prevalence.

15.
Nihon Rinsho ; 66(10): 1965-9, 2008 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-18939498

RESUMO

Despite tremendous efforts to develop HIV vaccines eliciting virus-specific T-cell responses, whether this strategy can really result in HIV control remains unknown. It is important to determine what T-cell responses are responsible for primary HIV control. Recently, encouraging HIV vaccine trials indicated that vaccine induction of highly effective cytotoxic T lymphocytes (CTLs) may result in viral containment in a macaque AIDS model. CTLs exerting strong suppressive effect on viral replication frequently select for escape mutations at the cost of viral fitness. Thus, analysis of CTL-induced viral polymorphisms would contribute to determination of effective CTLs that may be essential for HIV control.


Assuntos
Vacinas contra a AIDS , Desenho de Fármacos , Animais , Evolução Molecular , HIV/genética , HIV/fisiologia , Humanos , Mutação , Linfócitos T Citotóxicos/imunologia , Replicação Viral
16.
J Virol ; 82(10): 5093-8, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18337572

RESUMO

Cytotoxic T-lymphocyte (CTL) responses frequently select for immunodeficiency virus mutations that result in escape from CTL recognition with viral fitness costs. The replication in vivo of such viruses carrying not single but multiple escape mutations in the absence of the CTL pressure has remained undetermined. Here, we have examined the replication of simian immunodeficiency virus (SIV) with five gag mutations selected in a macaque possessing the major histocompatibility complex haplotype 90-120-Ia after its transmission into 90-120-Ia-negative macaques. Our results showed that even such a "crippled" SIV infection can result in persistent viral replication, multiple reversions, and AIDS progression.


Assuntos
Mutação , Síndrome de Imunodeficiência Adquirida dos Símios/transmissão , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/genética , Vírus da Imunodeficiência Símia/imunologia , Linfócitos T Citotóxicos/imunologia , Animais , Produtos do Gene gag/genética , Macaca mulatta , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia/crescimento & desenvolvimento , Carga Viral
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