Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 174
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
Ann Oncol ; 27(3): 397-408, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26681686

RESUMO

Malignancies represent a major cause of morbidity and mortality in human immunodeficiency virus (HIV)-infected patients. The introduction of combined antiretroviral therapy has modified the spectrum of malignancies in HIV infection with a decreased incidence of acquired immunodeficiency syndrome (AIDS) malignancies such as Kaposi's sarcoma and non-Hodgkin's lymphoma due to partial immune recovery and an increase in non-AIDS-defining malignancies due to prolonged survival. Management of HIV-infected patients with cancer requires a multidisciplinary approach, involving both oncologists and HIV physicians to optimally manage both diseases and drug interactions between anticancer and anti-HIV drugs. The French CANCERVIH group presents here a review and an experience of managing non-AIDS malignancies in HIV-infected individuals.


Assuntos
Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Terapia Antirretroviral de Alta Atividade , Doença de Hodgkin/epidemiologia , Sarcoma de Kaposi/epidemiologia , Consenso , Prova Pericial , Doença de Hodgkin/terapia , Humanos , Prognóstico , Risco , Sarcoma de Kaposi/terapia
2.
HIV Med ; 16(9): 553-62, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25944318

RESUMO

OBJECTIVES: The aim of the study was to assess the impact of rapid and sustained viral control produced by combination antiretroviral therapy (cART) on HIV-associated immune activation and inflammation. METHODS: In this longitudinal observational study, we examined changes in interleukin-6 (IL-6), interferon-γ-inducible protein-10 (IP-10), monokine induced by interferon-γ (MIG) and soluble CD14 (sCD14) levels during 2 years of effective first-line cART. Biomarker levels before and after cART were compared with those observed in healthy subjects, using the Wilcoxon signed rank test. Elevated biomarker levels were defined with respect to values for healthy subject (mean + 2 standard deviations). Factors associated with persistently elevated biomarker levels after 2 years of cART were identified by logistic regression. RESULTS: We included in the study 139 patients with a median HIV-1 RNA level of 4.8 log10 HIV-1 RNA copies/mL and a median CD4 cell count of 294 cells/µL at cART initiation [day 0 (D0)]. At D0, all biomarker levels were higher than in healthy subjects (P < 0.05). After 2 years of cART, IL-6, IP-10 and MIG levels fell significantly, by a median of 0.54, 420 and 1107 pg/mL, respectively (all P < 0.001), and were no longer elevated in > 75% of patients. In contrast, sCD14 levels did not change significantly (0.18 × 10(6) pg/mL; P = 0.102) and remained elevated. Older age was associated with elevated levels of IP-10 [odds ratio (OR) 1.60 per 10 years older; P = 0.047] and MIG (OR 1.92 per 10 years older; P = 0.007) after 2 years of cART. CONCLUSIONS: The rapid and sustained viral suppression produced by first-line cART reduced IL-6, IP-10 and MIG to normal levels, while sCD14, a marker of monocyte activation, remained elevated. High levels of IP-10 and MIG tended to persist in older patients.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade/métodos , Biomarcadores/sangue , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Adulto , Fatores Etários , Quimiocina CXCL10/sangue , Quimiocina CXCL9/sangue , Feminino , Infecções por HIV/sangue , Humanos , Interleucina-6/sangue , Receptores de Lipopolissacarídeos/sangue , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
5.
J Infect Dis ; 205(5): 718-24, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22238471

RESUMO

We performed a genome-wide association study comparing a cohort of 144 human immunodeficiency virus (HIV type 1-infected, untreated white long-term nonprogressors (LTNPs) with a cohort of 605 HIV-1-infected white seroconverters. Forty-seven single-nucleotide polymorphisms (SNPs), located from class I to class III major histocompatibility complex (MHC) subregions, show statistical association (false discovery rate, <0.05) with the LTNP condition, among which 5 reached genome-wide significance after Bonferonni correction. The MHC LTNP-associated SNPs are ordered in ≥4 linkage disequilibrium blocks; interestingly, an MHC class III linkage disequilibrium block (defined by the rs9368699 SNP) seems specific to the LTNP phenotype.


Assuntos
Progressão da Doença , Genes MHC Classe I/genética , Infecções por HIV/genética , HIV-1 , Polimorfismo de Nucleotídeo Único , Proteínas de Ligação a DNA/genética , Frequência do Gene , Estudo de Associação Genômica Ampla , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Complexo Principal de Histocompatibilidade/genética , RNA Longo não Codificante , RNA não Traduzido , Fatores de Tempo , Fatores de Transcrição/genética
6.
Arthritis Rheum ; 63(11): 3502-11, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21811996

RESUMO

OBJECTIVE: To assess the factors influencing the efficacy of 2 injections of a pandemic 2009 influenza A (H1N1) vaccine in patients with systemic lupus erythematosus (SLE). METHODS: We conducted a single-center, observational prospective study of 111 patients who were vaccinated with a monovalent, inactivated, nonadjuvanted, split-virus vaccine during December 2009 and January 2010 and received a second dose of vaccine 3 weeks later. The antibody response was evaluated using the hemagglutination inhibition assay according to the guidelines recommended for the pandemic vaccine, consisting of 3 immunogenicity criteria (i.e., a seroprotection rate of 70%, a seroconversion rate of 40%, and a geometric mean ratio [GMR] of 2.5). RESULTS: The 3 immunogenicity criteria were met on day 42 (seroprotection rate 80.0% [95% confidence interval (95% CI) 72.5-87.5%], seroconversion rate 71.8% [95% CI 63.4-80.2%], and GMR 10.3 [95% CI 2.9-14.2]), while only 2 criteria were met on day 21 (seroprotection rate 66.7% [95% CI 57.9-75.4%], seroconversion rate 60.4% [95% CI 51.3-69.5%], and GMR 8.5 [95% CI 3.2-12.0]). The vaccine was well tolerated. Disease activity, assessed by the Safety of Estrogens in Lupus Erythematosus National Assessment version of the SLE Disease Activity Index, the British Isles Lupus Assessment Group score, and the Systemic Lupus Activity Questionnaire, did not increase. In the multivariate analysis, vaccination failure was significantly associated with immunosuppressive treatment or a lymphocyte count of ≤ 1.0 × 109/liter. The second injection significantly increased the immunogenicity in these subgroups, but not high enough to fulfill the seroprotection criterion in patients receiving immunosuppressive treatment. CONCLUSION: Our findings indicate that the efficacy of the vaccine was impaired in patients who were receiving immunosuppressive drugs or who had lymphopenia. A second injection increased vaccine immunogenicity without reaching all efficacy criteria for a pandemic vaccine in patients receiving an immunosuppressive agent. These results open possibilities for improving anti-influenza vaccination in SLE.


Assuntos
Hospedeiro Imunocomprometido/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Lúpus Eritematoso Sistêmico/imunologia , Adulto , Formação de Anticorpos , Feminino , Humanos , Vacinas contra Influenza/efeitos adversos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
7.
Nat Med ; 4(2): 215-21, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9461196

RESUMO

The T-cell antigen receptor (TCR) repertoire was studied longitudinally by analyzing the varying lengths of the beta chain CDR3 hypervariable region during the course of HIV-1 infection and following combination antiretroviral therapy. Drastic restrictions in CD8+ T-cell repertoire usage were found at all stages of natural progression and persisted during the first six months of treatment. In contrast, significant CD4+ T-cell repertoire perturbations were not found in early stages of infection but correlated with progression to AIDS. Out of ten patients presenting with pretreatment perturbations, normalization of the CD4+ repertoire was observed in eight good responders, but not in two cases of unsuccessful therapy. These results indicate that, besides CD4+ cell count rise, an efficient control of HIV replication may allow qualitative modifications of the CD4+ repertoire balance.


Assuntos
Síndrome da Imunodeficiência Adquirida/imunologia , Fármacos Anti-HIV/uso terapêutico , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Adulto , Sequência de Aminoácidos , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/virologia , Interpretação Estatística de Dados , Progressão da Doença , Quimioterapia Combinada , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Receptores de Antígenos de Linfócitos T/efeitos dos fármacos
8.
J Exp Med ; 188(3): 609-14, 1998 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-9687538

RESUMO

CC chemokines produced by CD8(+) T cells are known to act as HIV-suppressive factors. We studied the possible role of these chemokines in HIV-1-specific killing of target cells. We found that the activity of cytotoxic T lymphocytes (CTLs) in CTL lines or freshly isolated peripheral blood mononuclear cells from HIV-1-infected individuals is markedly enhanced by RANTES (regulated on activation, normal T cell expressed and secreted) and virtually abolished by an antibody neutralizing RANTES or the RANTES receptor antagonist RANTES(9-68). Lysis was mediated by CD8(+) major histocompatibility complex class I-restricted T cells and was obtained with target cells expressing epitopes of the HIV-1LAI proteins Gag, Pol, Env, and Nef. The cytolytic activity observed in the presence or absence of added RANTES could be abolished by pretreatment of the CTLs with pertussis toxin, indicating that the effect is mediated by a G protein-coupled receptor. The chemokines monocyte chemotactic protein (MCP)-3, MCP-4, and eotaxin acted like RANTES, whereas macrophage inflammatory protein (MIP)-1alpha, MIP-1beta, MCP-1, and stromal cell-derived factor 1 were inactive, suggesting a role for the eotaxin receptor, CCR3, and ruling out the involvement of CCR1, CCR2, CCR5, and CXCR4. CTL activity was abrogated by an antibody that blocks CCR3, further indicating that specific lysis is triggered via this chemokine receptor. These observations reveal a novel mechanism for the induction of HIV-1-specific cytotoxicity that depends on RANTES acting via CCR3.


Assuntos
Quimiocina CCL5/imunologia , Citotoxicidade Imunológica , Infecções por HIV/imunologia , HIV-1/imunologia , Receptores de Quimiocinas/imunologia , Linhagem Celular , Quimiocina CCL5/farmacologia , Humanos , Receptores CCR3
9.
Science ; 277(5322): 112-6, 1997 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-9204894

RESUMO

Highly active antiretroviral therapy (HAART) increases CD4(+) cell numbers, but its ability to correct the human immunodeficiency virus (HIV)-induced immune deficiency remains unknown. A three-phase T cell reconstitution was demonstrated after HAART, with: (i) an early rise of memory CD4(+) cells, (ii) a reduction in T cell activation correlated to the decreasing retroviral activity together with an improved CD4(+) T cell reactivity to recall antigens, and (iii) a late rise of "naïve" CD4(+) lymphocytes while CD8(+) T cells declined, however, without complete normalization of these parameters. Thus, decreasing the HIV load can reverse HIV-driven activation and CD4(+) T cell defects in advanced HIV-infected patients.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , HIV-1 , Subpopulações de Linfócitos T/imunologia , Adulto , Antígenos Virais/imunologia , Contagem de Linfócito CD4 , Linfócitos T CD8-Positivos/imunologia , Quimioterapia Combinada , Inibidores da Protease de HIV/administração & dosagem , Inibidores da Protease de HIV/uso terapêutico , HIV-1/efeitos dos fármacos , HIV-1/fisiologia , Homeostase , Humanos , Memória Imunológica , Ativação Linfocitária , Contagem de Linfócitos , Pessoa de Meia-Idade , RNA Viral/sangue , Inibidores da Transcriptase Reversa/administração & dosagem , Inibidores da Transcriptase Reversa/uso terapêutico , Ritonavir/uso terapêutico , Tuberculina/imunologia , Carga Viral , Viremia , Zalcitabina/administração & dosagem , Zalcitabina/uso terapêutico , Zidovudina/administração & dosagem , Zidovudina/uso terapêutico
10.
Science ; 287(5461): 2274-7, 2000 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-10731151

RESUMO

Human immunodeficiency virus (HIV) enters cells in vitro via CD4 and a coreceptor. Which of 15 known coreceptors are important in vivo is poorly defined but may be inferred from disease-modifying mutations, as for CCR5. Here two single nucleotide polymorphisms are described in Caucasians in CX3CR1, an HIV coreceptor and leukocyte chemotactic/adhesion receptor for the chemokine fractalkine. HIV-infected patients homozygous for CX3CR1-I249 M280, a variant haplotype affecting two amino acids (isoleucine-249 and methionine-280), progressed to AIDS more rapidly than those with other haplotypes. Functional CX3CR1 analysis showed that fractalkine binding is reduced among patients homozygous for this particular haplotype. Thus, CX3CR1-I249 M280 is a recessive genetic risk factor in HIV/AIDS.


Assuntos
Síndrome da Imunodeficiência Adquirida/fisiopatologia , Quimiocinas CX3C , Infecções por HIV/fisiopatologia , Polimorfismo de Nucleotídeo Único , Receptores de Citocinas/genética , Receptores de Citocinas/fisiologia , Receptores de HIV/genética , Receptores de HIV/fisiologia , Síndrome da Imunodeficiência Adquirida/genética , Síndrome da Imunodeficiência Adquirida/virologia , Receptor 1 de Quimiocina CX3C , Estudos de Casos e Controles , Quimiocina CX3CL1 , Quimiocinas CXC/metabolismo , Cromossomos Humanos Par 3 , Estudos de Coortes , Progressão da Doença , Variação Genética , Genótipo , HIV/fisiologia , Infecções por HIV/genética , Infecções por HIV/virologia , Haplótipos , Homozigoto , Humanos , Leucócitos Mononucleares/metabolismo , Desequilíbrio de Ligação , Proteínas de Membrana/metabolismo , Mutação , Polimorfismo de Fragmento de Restrição , Polimorfismo Conformacional de Fita Simples , Análise de Sobrevida , População Branca/genética
11.
Rev Mal Respir ; 36(9): 1047-1056, 2019 Nov.
Artigo em Francês | MEDLINE | ID: mdl-31522947

RESUMO

The aging population raises a number of public health issues including a need to address the severity and frequency of infections observed in older people. Vaccines play an important role in prevention. However, immunosenescence alters the intensity and quality of vaccine responses, thus limiting the impact of recommendations directed after 65 years for vaccination against flu, pneumococci, pertussis, tetanus and zoster. Immunosenescence, aggravated by co-morbidities, varies with age, becoming apparent after 60-65 years and more profound after 85 years. All stages of vaccine responses are affected by immunosenescence, from the innate immunity required to activate these responses to the induction of protective antibody responses and immune memory. Nevertheless, the capacity to develop new responses to primary vaccination is more affected than the ability to respond to recalls, although this is also impaired. Responses to vaccines are differentially altered depending on vaccine and age. Influenza vaccines are modestly immunogenic and several meta-analyses agree an estimate for efficacy of about 50% against virologically-proven flu and 40% against flu-related deaths. The anti-pneumococcal 23-valent non-conjugated vaccine does not induce memory while the 13-valent conjugated one does, but their efficacy are likely to be similar between 70 to 52% before 75 years. A sequential vaccination program with the 13-valent primo-vaccination followed by the 23-valent, recommended in immune-suppressed patients, is currently being studied in France. The waning of immunity to pertussis makes recalls necessary in the elderly who develop good antibody responses. Several research avenues are currently being pursued to try improve the degree of protection conferred by these vaccines in elderly.


Assuntos
Imunogenicidade da Vacina , Imunossenescência , Vacinas/imunologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Humanos , Vacinas contra Influenza/imunologia , Pessoa de Meia-Idade , Vacinas Pneumocócicas/imunologia
12.
Clin Exp Immunol ; 152(2): 252-7, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18410636

RESUMO

INITIO is an open-labelled randomized trial evaluating first-line therapeutic strategies for human immunodeficiency virus-1 (HIV-1) infection. In an immunology substudy a tetanus toxoid booster (TTB) immunization was planned for 24 weeks after initiation of highly active antiretroviral therapy (HAART). All patients had received tetanus toxoid immunization in childhood. Generation of proliferative responses to tetanus toxoid was compared in two groups of patients, those receiving a protease inhibitor (PI)-sparing regimen (n = 21) and those receiving a PI-containing (n = 54) regimen. Fifty-two participants received a TTB immunization [PI-sparing (n = 15), PI-containing (n = 37)] and 23 participants did not [PI-sparing (n = 6) or PI-containing (n = 17)]. Cellular responses to tetanus antigen were monitored by lymphoproliferation at time of immunization and every 24 weeks to week 156. Proportions with a positive response (defined as stimulation index > or = 3 and Delta counts per minute > or = 3000) were compared at weeks 96 and 156. All analyses were intent-to-treat. Fifty-two participants had a TTB immunization at median 25 weeks; 23 patients did not. At weeks 96 and 156 there was no evidence of a difference in tetanus-specific responses, between those with or without TTB immunization (P = 0.2, P = 0.4). There was no difference in the proportion with response between those with PI-sparing or PI-containing regimens at both time-points (P = 0.8, P = 0.7). The proliferative response to tetanus toxoid was unaffected by initial HAART regimen. Anti-tetanus responses appear to reconstitute eventually in most patients over 156 weeks when treated successfully with HAART, irrespective of whether or not a TTB immunization has been administered.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/imunologia , HIV-1/isolamento & purificação , Toxoide Tetânico/imunologia , Terapia Antirretroviral de Alta Atividade , Contagem de Linfócito CD4 , Proliferação de Células , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Humanos , Imunidade Celular , Imunização , Imunização Secundária , Ativação Linfocitária/imunologia , Carga Viral
13.
EBioMedicine ; 27: 51-60, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29273355

RESUMO

BACKGROUND: We describe a homosexual man who strongly controlled HIV-1 for ten years despite lack of protective genetic background. METHODS: HIV-1 DNA was measured in blood and other tissues. Cell susceptibility was evaluated with various strains. HIV-1-specific (CD4 and CD8 activation markers and immune check points) and NK cells responses were assessed; KIRs haplotypes and HLA alleles were determined. FINDINGS: Two HIV-1 RNA copies/mL of plasma were detected in 2009, using an ultra-sensitive assay. HIV-DNA was detected at 1.1 and 2 copies/106 PBMCs in 2009 and 2015 respectively, at 1.2 copies/106 cells in rectal cells in 2011. WBs showed weak reactivity with antibodies to gp160, p55 and p25 from 2007 to 2014, remaining incomplete in 2017. CD4 T cells were susceptible to various strains including HIVKON, a primary isolate of his own CRF02_AG variant. CD8 T cells showed a strong poly-functional response against HIV-Gag, producing mainly IFN-γ; a robust capacity of antibody-dependant cell cytotoxicity (ADCC) was observed in NK cells. Case patient was group B KIR haplotype. Neutralizing antibodies were not detected. CD4 and CD8 blood T cells showed normal proportions without increased activation markers. Phylogenetic analyses identified the same CRF02_AG variant in his partner. The patient and his partner were heterozygous for the CCR5ΔD32 deletion and shared HLA-B*07, C*07 non-protective alleles. INTERPRETATION: This thorough description of the natural history of an individual controlling HIV-1 in various compartments for ten years despite lack of protective alleles, and of his partner, may have implications for strategies to cure HIV-1 infection.


Assuntos
Patrimônio Genético , Homossexualidade Masculina/genética , Parceiros Sexuais , Adulto , Infecções por HIV/genética , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/fisiologia , Humanos , Masculino , Filogenia , Linfócitos T/imunologia
14.
J Clin Invest ; 86(6): 2117-24, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1979339

RESUMO

The interference of the recombinant HIV-1 glycoproteins gp160 and gp120 with the CD3/T cell antigen receptor (TcR)-mediated activation process has been investigated in the CD4+ diphtheria toxoid-specific human P28D T cell clone. Both glycoproteins clearly inhibit the T cell proliferation induced in an antigen-presenting cell (APC)-free system by various cross-linked monoclonal antibodies specific for the CD3 molecule or the TcR alpha chain (up to 80% inhibition). Biochemical studies further demonstrate that exposure of the T cell clone to both glycoproteins (gps) specifically inhibits the CD3/TcR phospholipase C (PLC) transduction pathway, without affecting the CD3/TcR cell surface expression. Thus, inositol phosphate production, phosphatidic acid turnover, intracellular free calcium, and intracellular pH increase induced by CD3/TcR-specific MAbs are specifically impaired in gps-treated P28D T cells. Addition of purified soluble CD4 prevents binding of gps to T cells and overcomes all observed inhibitions. Maximal inhibitions are obtained for long-term exposure of the T cell clone to gps (16 h). No early effect of gps is observed. By contrast, gp160 and gp120 fail to suppress the CD2-triggered functional and biochemical P28D T cell responses. These results demonstrate that, in addition to their postulated role in the alteration of the interaction between CD4 on T lymphocytes and MHC class II molecules on APC, soluble HIV-1 envelope glycoproteins may directly and specifically impair the CD3/TcR-mediated activation of PLC in uninfected T cells via the CD4 molecule.


Assuntos
Antígenos de Diferenciação de Linfócitos T/fisiologia , Linfócitos T CD4-Positivos/fisiologia , Produtos do Gene env/farmacologia , Proteína gp120 do Envelope de HIV/farmacologia , HIV-1/imunologia , Fosfatidilinositóis/fisiologia , Receptores de Antígenos de Linfócitos T/fisiologia , Transdução de Sinais/efeitos dos fármacos , Antígenos CD/fisiologia , Antígenos CD2 , Complexo CD3 , Cálcio/fisiologia , Células Clonais , Humanos , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Ativação Linfocitária/efeitos dos fármacos , Receptores Imunológicos/fisiologia
15.
J Clin Invest ; 89(1): 53-60, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1370302

RESUMO

Cytotoxic T lymphocytes (CTL) specific for human immunodeficiency virus (HIV) proteins have been analyzed in lymphoid organs from seropositive patients. Indeed, an active HIV replication coexists with a major CD8+ lymphocytic infiltration in these organs. We have shown in a previous report that HIV-seropositive patients lungs were infiltrated by HIV specific CD8+ lymphocytes. In the present report, we show that HIV-specific CTL responses can also be detected in lymph nodes and spleens, and were mainly directed against the ENV, GAG, and NEF HIV-1 proteins. The primary NEF-specific CTL responses were further characterized by epitope mapping. Determination of epitope-specific CTL frequencies were performed by limiting dilution analysis. Our results indicated that, in addition to the central region of NEF (AA66-148), a new immunodominant region is recognized by CTL. This region corresponds to the carboxyl-terminal domain of NEF (amino acids 182-206). AA182-206 is recognized in association with at least two common human histocompatibility leukocyte antigen (HLA) molecules (HLA-A1 and B8), with clonal frequencies of one CTL per 10(-5) to 10(-6) splenic lymphocytes. Our data indicate that lymphoid organs may represent a major reservoir for in vivo activated HIV-specific CTL. Furthermore, the carboxyl-terminal domain of NEF was found to be conserved among several HIV strains. Therefore, our finding is of interest for further HIV vaccines development.


Assuntos
Produtos do Gene nef/imunologia , HIV-1/imunologia , Tecido Linfoide/imunologia , Oligopeptídeos/imunologia , Linfócitos T Citotóxicos/imunologia , Sequência de Aminoácidos , Epitopos/imunologia , Produtos do Gene env/imunologia , Produtos do Gene gag/imunologia , Antígenos HLA/imunologia , Humanos , Linfonodos/imunologia , Dados de Sequência Molecular , Oligopeptídeos/síntese química , Baço/imunologia , Produtos do Gene nef do Vírus da Imunodeficiência Humana
16.
Curr Opin Immunol ; 8(4): 546-53, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8794018

RESUMO

Exceptionally potent cytotoxic T lymphocyte responses are generated after HIV invasion and probably control the primary infection as well as the asymptomatic phase of HIV infection. The chronic phase appears as a quasi-equilibrium between waves of new HIV variants and variant-specific CTLs, thus sustaining continuous CTL activation which eventually fails to eradicate HIV disease progression and the reascension of viral replication. Meanwhile, both the host and the virus develop various strategies either to stop or to evade this potentially deleterious permanent CTL activity. The transient effectiveness of CTLs opens perspectives for understanding disease progression generally as well as for immune therapeutic strategies.


Assuntos
Evolução Molecular , HIV/imunologia , Linfócitos T Citotóxicos/classificação , Linfócitos T Citotóxicos/imunologia , Portador Sadio/imunologia , Humanos
17.
Curr Opin Immunol ; 13(4): 483-8, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11498306

RESUMO

Immune reconstitution during antiretroviral therapy has recently been shown to depend upon multiple factors at work in T cell homeostasis, amongst which the reduction of thymus dysfunction and of immune hyperactivation are instrumental. The optimism that has been raised by the restoration of hosts' defenses against opportunistic pathogens is, however, balanced by the poor immunity restored against HIV; thus, innovative immune interventions are required.


Assuntos
Terapia Antirretroviral de Alta Atividade , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Homeostase/imunologia , Humanos , Memória Imunológica , Cinética , Ativação Linfocitária , Modelos Biológicos , Timo/imunologia
19.
AIDS ; 19(1): 25-33, 2005 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-15627030

RESUMO

BACKGROUND: It is unclear how stable low-level viral replication and CD4 cell numbers can be maintained under highly active antiretroviral therapy (HAART). This study was designed to analyse whether HIV-specific responses in stable partially controlled patients during antiretroviral therapy (ART) differ from those observed in complete HAART failure and whether they contribute to the control of viral load (VL). METHODS: Three groups of patients were selected according to plasma HIV RNA levels during 18 months of ART: persistently low VL (LoVL; HIV RNA <10,000 copies/ml; n = 28), undetectable VL (UnVL; HIV RNA <200 copies/ml; n = 29) and high VL (HiVL; HIV RNA >10,000 copies/ml; n = 14). T-cell responses were studied using lymphoproliferative and interferon (IFN)-gamma-ELISpot assays against HIV-p24, -gp160, recall antigens, and 15 pools of HIV-(Gag + RT) peptides. RESULTS: Frequencies of IFN-gamma-producing CD4 T cells against HIV-p24 were higher in LoVL than in UnVL or HiVL groups [median, 131, 47 and 23 spot-forming cells (SFC)/1 x 10 peripheral blood mononuclear cells (PBMC), respectively; P = 0.012 and P = 0.047]. Lymphoproliferative responses to HIV-p24 and recall antigens were similar in LoVL and UnVL groups but lower in HiVL (P = 0.004). Frequencies of HIV-specific CD8 T cells were higher in LoVL than in UnVL (1340 versus 410 SFC/1 x 10 PBMC; P = 0.001). They correlated negatively with VL in the LoVL and HiVL (r, -0.393, P = 0.039 and r, -0.643, P = 0.024, respectively) and positively correlated with anti-HIV CD4 cell frequencies in the LoVL group only (r, 0.420; P = 0.026). CONCLUSION: Persistently low viral replication (<10,000 copies/ml) during ART stimulates high frequencies of HIV-specific CD4 and CD8 T cells compared to full virus suppression or complete ART failure. The association of high anti-HIV activity with large numbers of HIV-specific CD8 T cells contribute to the control of viral replication.


Assuntos
Antirretrovirais/uso terapêutico , Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/tratamento farmacológico , HIV-1/fisiologia , Replicação Viral/fisiologia , Adulto , Idoso , Antígenos Virais/imunologia , Terapia Antirretroviral de Alta Atividade/métodos , Linfócitos T CD8-Positivos/imunologia , Estudos Transversais , Feminino , Infecções por HIV/imunologia , Infecções por HIV/virologia , Humanos , Interferon gama/imunologia , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Inibidores da Transcriptase Reversa/uso terapêutico , Carga Viral/métodos , Proteínas Virais/imunologia
20.
Leukemia ; 13(2): 230-40, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10025897

RESUMO

Leukemic T-LGL (large granular lymphocyte) composed of clonal CD3+ TCR alphabeta+ CD8+ CD57+ cells were compared with oligoclonally CD3+ CD8hi+ CD57- lymphocytes expanded after BMT. Leukemic CD3+ CD8hi+ CD57+ LGL showed several phenotypic differences such as an upregulation of CD16 and adhesion molecules (mainly CD11c, CD58 and CD54), activation markers and an exclusive CD45RA isoform expression. Unstimulated CD3+ CD8+ CD57+ LGL from both leukemic and BMT donors spontaneously developed an ex vivo CTL-like CD3-redirected cytotoxicity but no NK cell activity. Different stimuli (PHA, PMA or rhIL-2) induced similar cytotoxic profiles after a 6-day culture involving a CD3-redirected lysis predominating over a low NK cell activity. However, culture of leukemic LGL with these stimuli allowed either a 2 week persistence (PMA or rhIL-2) of CD8+ CD57+ LGL or their disappearance after 3 days (PHA). Furthermore, leukemic CD8hi+ CD57+ T lymphocytes produced an inhibitor of cytotoxic functions as previously described for BMT recipients' CD8+ CD57+ cells. Thus, despite some phenotypic differences between both cell sources, leukemic CD57+ T-LGL display the same functional characteristics of cytotoxic effector and immunoregulatory T cells as CD8+ CD57+ T cells from BMT recipients which might represent their normal counterpart.


Assuntos
Transplante de Medula Óssea , Complexo CD3/sangue , Antígenos CD57/sangue , Antígenos CD8/sangue , Leucemia Linfoide/terapia , Estudos de Casos e Controles , Feminino , Humanos , Imunofenotipagem , Interleucina-2/uso terapêutico , Leucemia Linfoide/imunologia , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico , Estimulação Química
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa