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1.
Vaccine ; 36(19): 2683-2686, 2018 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-29606517

RESUMO

This Phase I/II, open, long-term follow-up study was conducted in antiretroviral therapy (ART)-naïve (N = 212) and ART-treated (N = 19) human immunodeficiency virus 1 (HIV-1)-infected adults, who received an HIV-1 investigational vaccine (F4/AS01B) or placebo in two previous studies (NCT00814762 and NCT01218113). After a minimum of two years and a maximum of four years of follow-up post-vaccination per patient, no significant differences were observed between F4/AS01B and placebo groups in terms of viral load, CD4+ T-cell count and incidence of specific clinical events. Vaccine-induced polyfunctional CD4+ T-cells persisted up to study end and no relevant vaccine-related safety events were reported in F4/AS01B groups. This study has been registered at ClinicalTrials.gov (NCT01092611).


Assuntos
Vacinas contra a AIDS/uso terapêutico , Infecções por HIV/terapia , Linfócitos T CD4-Positivos/imunologia , Seguimentos , Infecções por HIV/tratamento farmacológico , HIV-1/imunologia , HIV-1/patogenicidade , Humanos , Placebos , Carga Viral
3.
Medicine (Baltimore) ; 95(6): e2673, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26871794

RESUMO

The impact of the investigational human immunodeficiency virus type 1 (HIV-1) F4/AS01B vaccine on HIV-1 viral load (VL) was evaluated in antiretroviral therapy (ART)-naive HIV-1 infected adults.This phase IIb, observer-blind study (NCT01218113), included ART-naive HIV-1 infected adults aged 18 to 55 years. Participants were randomized to receive 2 (F4/AS01B_2 group, N = 64) or 3 (F4/AS01B_3 group, N = 62) doses of F4/AS01B or placebo (control group, N = 64) at weeks 0, 4, and 28. Efficacy (HIV-1 VL, CD4 T-cell count, ART initiation, and HIV-related clinical events), safety, and immunogenicity (antibody and T-cell responses) were evaluated during 48 weeks.At week 48, based on a mixed model, no statistically significant difference in HIV-1 VL change from baseline was demonstrated between F4/AS01B_2 and control group (0.073 log10 copies/mL [97.5% confidence interval (CI): -0.088; 0.235]), or F4/AS01B_3 and control group (-0.096 log10 copies/mL [97.5% CI: -0.257; 0.065]). No differences between groups were observed in HIV-1 VL change, CD4 T-cell count, ART initiation, or HIV-related clinical events at intermediate timepoints. Among F4/AS01B recipients, the most frequent solicited symptoms were pain at injection site (252/300 doses), fatigue (137/300 doses), myalgia (105/300 doses), and headache (90/300 doses). Twelve serious adverse events were reported in 6 participants; 1 was considered vaccine-related (F4/AS01B_2 group: angioedema). F4/AS01B induced polyfunctional F4-specific CD4 T-cells, but had no significant impact on F4-specific CD8 T-cell and anti-F4 antibody levels.F4/AS01B had a clinically acceptable safety profile, induced F4-specific CD4 T-cell responses, but did not reduce HIV-1 VL, impact CD4 T-cells count, delay ART initiation, or prevent HIV-1 related clinical events.


Assuntos
Vacinas contra a AIDS/imunologia , Infecções por HIV/imunologia , Vacinas contra a AIDS/administração & dosagem , Adolescente , Adulto , Antirretrovirais , Anticorpos Antivirais , Formação de Anticorpos , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos , Feminino , Infecções por HIV/sangue , HIV-1/imunologia , Humanos , Masculino , Método Simples-Cego , Adulto Jovem
4.
PLoS One ; 8(5): e64405, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23741326

RESUMO

A successful HIV vaccine will likely induce both humoral and cell-mediated immunity, however, the enormous diversity of HIV has hampered the development of a vaccine that effectively elicits both arms of the adaptive immune response. To tackle the problem of viral diversity, T cell-based vaccine approaches have focused on two main strategies (i) increasing the breadth of vaccine-induced responses or (ii) increasing vaccine-induced responses targeting only conserved regions of the virus. The relative extent to which set-point viremia is impacted by epitope-conservation of CD8(+) T cell responses elicited during early HIV-infection is unknown but has important implications for vaccine design. To address this question, we comprehensively mapped HIV-1 CD8(+) T cell epitope-specificities in 23 ART-naïve individuals during early infection and computed their conservation score (CS) by three different methods (prevalence, entropy and conseq) on clade-B and group-M sequence alignments. The majority of CD8(+) T cell responses were directed against variable epitopes (p<0.01). Interestingly, increasing breadth of CD8(+) T cell responses specifically recognizing conserved epitopes was associated with lower set-point viremia (r = - 0.65, p = 0.009). Moreover, subjects possessing CD8(+) T cells recognizing at least one conserved epitope had 1.4 log10 lower set-point viremia compared to those recognizing only variable epitopes (p = 0.021). The association between viral control and the breadth of conserved CD8(+) T cell responses may be influenced by the method of CS definition and sequences used to determine conservation levels. Strikingly, targeting variable versus conserved epitopes was independent of HLA type (p = 0.215). The associations with viral control were independent of functional avidity of CD8(+) T cell responses elicited during early infection. Taken together, these data suggest that the next-generation of T-cell based HIV-1 vaccines should focus on strategies that can elicit CD8(+) T cell responses to multiple conserved epitopes of HIV-1.


Assuntos
Antígenos Virais/imunologia , Linfócitos T CD8-Positivos/imunologia , Sequência Conservada , Epitopos de Linfócito T/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Imunidade Celular , Sequência de Aminoácidos , Antígenos Virais/genética , Linfócitos T CD8-Positivos/patologia , Linfócitos T CD8-Positivos/virologia , Mapeamento de Epitopos , Epitopos de Linfócito T/genética , Expressão Gênica , Heterogeneidade Genética , Infecções por HIV/patologia , Infecções por HIV/virologia , HIV-1/crescimento & desenvolvimento , Homossexualidade Masculina , Humanos , Masculino , Dados de Sequência Molecular , Carga Viral/imunologia , Replicação Viral/imunologia
5.
Nat Med ; 17(8): 989-95, 2011 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-21765403

RESUMO

Specific human leukocyte antigens (HLAs), notably HLA-B*27 and HLA-B*57 allele groups, have long been associated with control of HIV-1. Although the majority of HIV-specific CD8(+) T cells lose proliferative capacity during chronic infection, T cells restricted by HLA-B*27 or HLA-B*57 allele groups do not. Here we show that CD8(+) T cells restricted by 'protective' HLA allele groups are not suppressed by T(reg) cells, whereas, within the same individual, T cells restricted by 'nonprotective' alleles are highly suppressed ex vivo. This differential sensitivity of HIV-specific CD8(+) T cells to T(reg) cell-mediated suppression correlates with their expression of the inhibitory receptor T cell immunoglobulin domain and mucin domain 3 (Tim-3) after stimulation with their cognate epitopes. Furthermore, we show that HLA-B*27- and HLA-B*57-restricted effectors also evade T(reg) cell-mediated suppression by directly killing T(reg) cells they encounter in a granzyme B (GzmB)-dependent manner. This study uncovers a previously unknown explanation for why HLA-B*27 and HLA-B*57 allele groups are associated with delayed HIV-1 disease progression.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Antígenos HLA-B/imunologia , Antígeno HLA-B27/imunologia , Linfócitos T Reguladores/virologia , Morte Celular/imunologia , Mapeamento de Epitopos , Feminino , Citometria de Fluxo , Regulação da Expressão Gênica/imunologia , Antígenos HLA-B/genética , Antígeno HLA-B27/genética , Receptor Celular 2 do Vírus da Hepatite A , Humanos , Masculino , Proteínas de Membrana/imunologia , Polimorfismo de Nucleotídeo Único/genética , Interferência de RNA , RNA Interferente Pequeno/genética
6.
J Acquir Immune Defic Syndr ; 58(3): 248-52, 2011 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-21709567

RESUMO

Most T cell-based HIV-1 vaccine candidates induce responses of limited breadth for reasons that are unclear. We evaluated vaccine-induced T-cell responses in individuals receiving an HIV-1 recombinant adenoviral vaccine. Certain HLA alleles (B27, B57, B35, and B14) are preferentially utilized to mount HIV-specific responses, whereas other alleles (A02 and B07) are rarely utilized (P < 0.001). This preference seems due to 4 following factors individually or in combination: higher affinity of specific peptides to specific HLA alleles; higher avidity of T-cell receptor; HLA and peptide interaction; and/or higher surface expression of certain HLA. Thus, HLA immunodominance plays a substantial role in vaccine-induced T-cell responses.


Assuntos
Vacinas contra a AIDS/imunologia , Epitopos de Linfócito T/imunologia , HIV-1/imunologia , Antígenos HLA/imunologia , Epitopos Imunodominantes/imunologia , Vacinas contra a AIDS/administração & dosagem , Alelos , Antígenos HLA/genética , Humanos , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia
7.
J Virol ; 84(9): 4461-8, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20147397

RESUMO

HLA alleles B57/58, B27, and B35 have the strongest genetic associations with HIV-1 disease progression. The mechanisms of these relationships may be host control of HIV-1 infection via CD8(+) T-cell responses. We examined these immune responses in subjects from the Seattle Primary Infection Cohort with these alleles. CD8(+) T-cell responses to conserved HIV epitopes within B57/58 alleles (TW10 and KF11) and B27 alleles (KK10 and FY10) delayed declines in CD4(+) T-cell counts (4 to 8 times longer), while responses to variable epitopes presented by B35 alleles (DL9 and IL9) resulted in more rapid progression. The plasma viral load was higher in B57/58(+) and B27(+) subjects lacking the conserved B57/58- and B27-restricted responses. The presence of certain B57/58-, B27-, and B35-restricted HIV-specific CD8(+) T-cell responses after primary HIV-1 infection better defined disease progression than the HLA genotype alone, suggesting that it is the HIV-specific CD8(+) T cells and not the presence of a particular HLA allele that determine disease progression. Further, the most effective host CD8(+) T-cell responses to HIV-1 were prevalent within an HLA allele, represented a high total allele fraction of the host CD8(+) T-cell response, and targeted conserved regions of HIV-1. These data suggest that vaccine immunogens should contain only conserved regions of HIV-1.


Assuntos
Predisposição Genética para Doença , Infecções por HIV/imunologia , HIV-1/imunologia , Antígenos HLA/genética , Contagem de Linfócito CD4 , Progressão da Doença , Feminino , Genótipo , Humanos , Masculino , Carga Viral
8.
Clin Infect Dis ; 47(6): 845-52, 2008 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-18687051

RESUMO

BACKGROUND: Long-term antiretroviral therapy (ART) is associated with lipodystrophy, peripheral neuropathy, lactic acidosis, and myopathy. Blepharoptosis, without prior ART association, is usually caused by age-associated involutional ptosis, but it is also seen in mitochondrial myopathies with external ophthalmoplegia, cardiac conduction disturbances, and neurological impairments. METHODS: Patients presented over a 2-year period. Four patients underwent surgical blepharoptosis repair. RESULTS: Five human immunodeficiency virus type 1-infected patients (median age, 50 years; range, 46-53 years) who were receiving ART presented with severe blepharoptosis; 2 of these 5 also presented with external ophthalmoplegia. Findings included decreased palpebral fissure height (median, 6.5 mm; normal height, 9 mm), mildly impaired levator function (median, 10 mm; normal, >13 mm), and markedly decreased marginal reflex distance (median, 0.5 mm; normal, 4 mm). A greater advancement of the levator aponeurosis was required during surgical repair, a finding consistent more with myogenic than with involutional blepharoptosis. All patients had severe lipodystrophy, which preceded blepharoptosis by a median interval of 4.7 years (range, 2.8-5.7 years). Four patients also presented with peripheral neuropathy and metabolic abnormalities before the onset of blepharoptosis, and 3 had cardiac conduction disturbances. Patients received ART for a median of 7.8 years (range, 4.9-11.2 years), thymidine analogue-containing ART for a median of 7.1 years (range, 1.2-7.9 years), and protease inhibitor-containing ART for a median of 7.1 years (range, 4.9-8.9 years). CONCLUSIONS: We report the novel findings of blepharoptosis and external ophthalmoplegia in patients who are receiving ART. Ptosis was preceded by lipodystrophy with long-term use of both thymidine-analogue- and protease inhibitor-containing ART. The findings are most consistent with myogenic ptosis in a generalized mitochondrial myopathy syndrome. Clinicians should also be watchful for other potential myopathic ptosis-associated complications, including proximal weakness, dysphagia, deafness, and cardiac conduction disturbances.


Assuntos
Antirretrovirais/efeitos adversos , Blefaroptose/induzido quimicamente , Oftalmoplegia/induzido quimicamente , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Assistência de Longa Duração , Masculino , Pessoa de Meia-Idade
9.
J Investig Med ; 53(1): 15-25, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16025877

RESUMO

BACKGROUND: Objective criteria for the assessment of patients with lipodystrophy syndrome in human immunodeficiency virus infection (LDHIV) have not emerged. METHODS: We compared regional body fat changes in 13 men with severe LDHIV on protease inhibitor-inclusive antiretroviral therapy with 13 control HIV-infected men using anthropometry, dual-energy X-ray absorptiometry (DEXA), and whole-body magnetic resonance imaging (MRI). RESULTS: LDHIV patients, compared with control subjects, had thinner gluteal, suprailiac, and triceps skinfolds (p < .01) and increased waist circumference (98 +/- 5 cm vs 86 +/- 9 cm, respectively; p = .0008). DEXA studies revealed reduced lower extremity fat (12 +/- 5% vs 22 +/- 9%; p = .0006), increased head and neck fat (18 +/- 3% vs 16 +/- 1%; p = .01), and increased proportion of total body fat in the trunk (65 +/- 7% vs 53 +/- 8%; p = .0005). MRI analysis revealed reduced thigh fat (12 +/- 5% vs 22 +/- 12%; p = .01), increased dorsocervical fat depth (47 +/- 24 mm vs 19 +/- 7 mm; p = .0009), and nearly significant increase in intra-abdominal fat (218 +/- 90 cm2 vs 157 +/- 70 cm2; p = .057). Interestingly, control subjects showed a positive relationship between intra-abdominal and dorsocervical fat (r= .57, p = .04), but the LDHIV patients showed a negative relationship (r= -.55, p = .05), suggesting a novel split phenotype among LDHIV patients of either dorsocervical or intra-abdominal fat accumulation. CONCLUSIONS: We conclude that MRI provides the best tools for definition of LDHIV syndrome and reveals variable phenotypes among LDHIV patients.


Assuntos
Absorciometria de Fóton/métodos , Tecido Adiposo/patologia , Antropometria/métodos , Composição Corporal , Síndrome de Lipodistrofia Associada ao HIV/diagnóstico , Imageamento por Ressonância Magnética , Adulto , Estudos de Casos e Controles , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Dobras Cutâneas
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