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BACKGROUND: The ambitious goal to eliminate new pediatric HIV infections by 2030 requires accelerated prevention strategies in high-risk settings such as South Africa. One approach could be pre-exposure prophylaxis (PrEP) with broadly neutralizing anti-HIV-1 monoclonal antibodies (bNAbs). The aim of our study is to define the optimal dose(s), the ideal combination(s) of bNAbs in terms of potency and breadth, and timing of subcutaneous (SC) administration(s) to prevent breast milk transmission of HIV. METHODS: Two bNAbs, CAP256V2LS and VRC07-523LS, will be assessed in a sequential and randomized phase I, single-site, single-blind, dose-finding trial. We aim to investigate the 28-day safety and pharmacokinetics (PK) profile of incrementally higher doses of these bNAbs in breastfeeding HIV-1 exposed born without HIV neonates alongside standard of care antiretroviral (ARV) medication to prevent (infants) or treat (mothers) HIV infection. The trial design includes 3 steps and 7 arms (1, 2, 3, 4, 5, 6 and 6b) with 8 infants in each arm. The first step will evaluate the safety and PK profile of the bNAbs when given alone as a single subcutaneous (SC) administration at increasing mg/kg body weight doses within 96 h of birth: arms 1, 2 and 3 at doses of 5, 10, and 20 mg/kg of CAP256V2LS, respectively; arms 4 and 5 at doses of 20 and 30 mg/kg of VRC07-523LS, respectively. Step two will evaluate the safety and PK profile of a combination of the two bNAbs administered SC at fixed doses within 96 h of birth. Step three will evaluate the safety and PK profile of the two bNAbs administered SC in combination at fixed doses, after 3 months. Arms 1 and 6 will follow sequential recruitment, whereas randomization will occur sequentially between arms (a) 2 & 4 and (b) 3 & 5. Before each randomization, a safety pause will allow review of safety data of the preceding arms. DISCUSSION: The results of this trial will guide further studies on bNAbs to prevent breast milk transmission of HIV. PROTOCOL VERSION: Version 4.0 dated 15 March 2024. TRIAL REGISTRATION: Pan African Clinical Trial Registry (PACTR): PACTR202205715278722, 21 April 2022; South African National Clinical Trial Registry (SANCTR): DOH-27-062022-6058.
Assuntos
Anticorpos Anti-HIV , Infecções por HIV , HIV-1 , Humanos , Infecções por HIV/prevenção & controle , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Infecções por HIV/transmissão , HIV-1/imunologia , Recém-Nascido , Feminino , Anticorpos Anti-HIV/administração & dosagem , Lactente , Injeções Subcutâneas , Anticorpos Monoclonais/farmacocinética , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/imunologia , Profilaxia Pré-Exposição/métodos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , África do Sul , Anticorpos Amplamente Neutralizantes/imunologia , Anticorpos Amplamente Neutralizantes/administração & dosagem , Aleitamento Materno , Fármacos Anti-HIV/farmacocinética , Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/uso terapêutico , Método Simples-Cego , Anticorpos Neutralizantes/imunologia , Masculino , Ensaios Clínicos Fase I como AssuntoRESUMO
The effects of two different dietary supplements on the redox status of healthy human participants were evaluated. The first supplement (GluS, Glutathione Synthesis) contains the precursors for the endogenous synthesis of glutathione and the second (GluReS, Glutathione and Resveratrol Synthesis) contains in addition polydatin, a precursor of resveratrol. To assess the influence of GluS and GluReS on the redox status, ten thiol species and three vitamins were measured before (t0) and after 8 weeks (t1) of dietary supplementation. An inflammatory marker, neopterin, was also assessed at the same time points. Both supplements were highly effective in improving the redox status by significantly increasing the reduced-glutathione (GSH) content and other reduced thiol species while significantly decreasing the oxidized species. The positive outcome of the redox status was most significant in the GluRes treatment group which also experienced a significant reduction in neopterin levels. Of note, the endogenous levels of vitamins C, E and A were significantly increased in both treatment groups, with best results in the GluReS group. While both dietary supplements significantly contributed to recognized antioxidant and anti-inflammatory outcomes, the effects of GluReS, the combination of glutathione and resveratrol precursors, were more pronounced. Thus, dietary supplementation with GluReS may represent a valuable strategy for maintaining a competent immune status and a healthy lifespan.
Assuntos
Antioxidantes/farmacologia , Suplementos Nutricionais , Glucosídeos/administração & dosagem , Glutationa/metabolismo , Resveratrol/metabolismo , Estilbenos/administração & dosagem , Vitaminas/sangue , Acetilcisteína/administração & dosagem , Idoso , Alanina/administração & dosagem , Ácido Ascórbico/sangue , Eritrócitos/metabolismo , Feminino , Glutamina/administração & dosagem , Glicina/administração & dosagem , Humanos , Ácidos Cetoglutáricos/administração & dosagem , Masculino , Pessoa de Meia-Idade , Neopterina/urina , Oxirredução , Compostos de Sulfidrila/sangue , Vitamina A/sangue , Vitamina E/sangueRESUMO
Surface expression of human leukocyte antigen (HLA)-class I molecules is critical for modulating T/natural killer lymphocytes' effector functions. Among HLA molecules, HLA-C, the most recently evolved form of class I antigens, is subjected to both transcriptional and multiple post-transcriptional regulation mechanisms affecting its cell surface expression. Among the latter a region placed in the 3' untranslated region of HLA-C transcript contains the single nucleotide polymorphism (SNP) rs67384697 "G-ins/del" that has been found to be strictly associated with surface levels of HLA-C allomorphs because of the effect on the binding site of a microRNA (Hsa-miR-148a). Higher expression of HLA-C has been proved to influence HIV-1 infection via a better control of viremia and a slower disease progression. More importantly, the analysis of SNP rs67384697 "G-ins/del" combined with the evaluation of the HLA-Bw4/-Bw6 C1/C2 supratype, as well as the killer immunoglobulin-like receptor genetic asset, has proved to be pivotal in defining the status of Elite Controllers in the Caucasian population. Here we describe a new reliable and fast method of allele-specific real-time PCR to monitor the integrity/disruption of the binding site of the microRNA Hsa-miR-148a in a high-throughput format that can be easily applied to studies involving large cohorts of individuals.
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MicroRNAs , Polimorfismo de Nucleotídeo Único , Alelos , Sítios de Ligação , Humanos , MicroRNAs/genética , Reação em Cadeia da Polimerase em Tempo RealRESUMO
The levels of expression of the HLA-class I molecules are critical for modulating T/NK lymphocytes effector functions. Among HLA molecules, HLA-C, the most recent developed form of class I antigens, is subjected to multiple post transcriptional level of regulation that affect its cell surface expression.We describe a new method of allele-specific real-time PCR that monitor the integrity/disruption of the binding site of the microRNA Hsa-miR-148a, a key factor associated to the levels of HLA-C expression in the Caucasian populations.
Assuntos
Antígenos HLA-C/genética , MicroRNAs/metabolismo , Reação em Cadeia da Polimerase em Tempo Real/métodos , Alelos , Sítios de Ligação/genética , DNA/genética , DNA/isolamento & purificação , Regulação da Expressão Gênica/imunologia , Antígenos HLA-C/imunologia , Voluntários Saudáveis , Humanos , Leucócitos Mononucleares , População Branca/genéticaRESUMO
This corrects the article DOI: 10.1038/srep40037.
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HLA-C expression is associated with a differential ability to control HIV-1 infection. Higher HLA-C levels may lead to better control of HIV-1 infection through both a higher efficiency of antigen presentation to cytotoxic T lymphocytes and the triggering of activating killer immunoglobulin-like receptors on NK cells, whereas lower levels may provide poor HIV-1 control and rapid progression to AIDS. We characterized the relative amounts of HLA-C heterotrimers (heavy chain/ß2 microglobulin [ß2m]/peptide) and HLA-C free heavy chains on peripheral blood mononuclear cells (PBMCs) from healthy blood donors harboring both alleles with stable or unstable binding to ß2m/peptide. We analyzed the stability of HLA-C heterotrimers of different allotypes and the infectivity of HIV-1 virions produced by PBMCs with various allotypes. We observed significant differences in HLA-C heterotrimer stability and in expression levels. We found that R5 HIV-1 virions produced by PBMCs harboring unstable HLA-C alleles were more infectious than those produced by PBMCs carrying the stable variants. We propose that HIV-1 infectivity might depend both on the amounts of HLA-C molecules and on their stability as trimeric complex. According to this model, individuals with low-expression HLA-C alleles and unstable binding to ß2m/peptide might have worse control of HIV-1 infection and an intrinsically higher capacity to support viral replication.IMPORTANCE Following HIV-1 infection, some people advance rapidly to AIDS while others have slow disease progression. HLA-C, a molecule involved in immunity, is a key determinant of HIV-1 control. Here we reveal how HLA-C variants contribute to the modulation of viral infectivity. HLA-C is present on the cell surface in two different conformations. The immunologically active conformation is part of a complex that includes ß2 microglobulin/peptide; the other conformation is not bound to ß2 microglobulin/peptide and can associate with HIV-1, increasing its infectivity. Individuals with HLA-C variants with a predominance of immunologically active conformations would display stronger immunity to HIV-1, reduced viral infectivity and effective control of HIV-1 infection, while subjects with HLA-C variants that easily dissociate from ß2 microglobulin/peptide would have a reduced immunological response to HIV-1 and produce more infectious virions. This study provides new information that could be useful in the design of novel vaccine strategies and therapeutic approaches to HIV-1.
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Membrana Celular/imunologia , Infecções por HIV/imunologia , HIV-1/fisiologia , Antígenos HLA-C/genética , Leucócitos Mononucleares/imunologia , Adulto , Alelos , Apresentação de Antígeno , Doadores de Sangue , Membrana Celular/genética , Membrana Celular/metabolismo , Feminino , Infecções por HIV/virologia , HIV-1/patogenicidade , Antígenos HLA-C/química , Antígenos HLA-C/imunologia , Antígenos HLA-C/metabolismo , Antígenos de Histocompatibilidade Classe I/classificação , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Células Matadoras Naturais/imunologia , Masculino , Pessoa de Meia-Idade , Linfócitos T Citotóxicos/imunologia , Adulto Jovem , Microglobulina beta-2/genética , Microglobulina beta-2/metabolismoRESUMO
Several studies demonstrated a relevant role of polymorphisms located within the HLA-B and -C loci and the Killer Immunoglobulin Receptors (KIRs) 3DL1 and 3DS1 in controlling HIV-1 replication. KIRs are regulatory receptors expressed at the surface of NK and CD8+ T-cells that specifically bind HLA-A and -B alleles belonging to the Bw4 supratype and all the -C alleles expressing the C1 or C2 supratype. We here disclose a novel signature associated with the Elite Controller but not with the long-term nonprogressor status concerning 2DS activating KIRs and HLA-C2 alleles insensitive to miRNA148a regulation. Overall, our findings support a crucial role of NK cells in the control of HIV-1 viremia.
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Infecções por HIV/imunologia , Infecções por HIV/metabolismo , Infecções por HIV/virologia , HIV-1/imunologia , Antígenos HLA-C/imunologia , Interações Hospedeiro-Patógeno/imunologia , Receptores KIR/agonistas , Alelos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/virologia , Cromossomos Humanos Par 19 , Cromossomos Humanos Par 6 , Progressão da Doença , Predisposição Genética para Doença , Genótipo , Infecções por HIV/genética , Antígenos HLA-C/genética , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Interações Hospedeiro-Patógeno/genética , Humanos , Razão de Chances , Polimorfismo Genético , Receptores KIR/genética , Receptores KIR/metabolismoRESUMO
HLA-C has been demonstrated to associate with HIV-1 envelope glycoprotein (Env). Virions lacking HLA-C have reduced infectivity and increased susceptibility to neutralizing antibodies. Like all others MHC-I molecules, HLA-C requires ß2-microglobulin (ß2m) for appropriate folding and expression on the cell membrane but this association is weaker, thus generating HLA-C free-chains on the cell surface. In this study, we deepen the understanding of HLA-C and Env association by showing that HIV-1 specifically increases the amount of HLA-C free chains, not bound to ß2m, on the membrane of infected cells. The association between Env and HLA-C takes place at the cell membrane requiring ß2m to occur. We report that the enhanced infectivity conferred to HIV-1 by HLA-C specifically involves HLA-C free chain molecules that have been correctly assembled with ß2m. HIV-1 Env-pseudotyped viruses produced in the absence of ß2m are less infectious than those produced in the presence of ß2m. We hypothesize that the conformation and surface expression of HLA-C molecules could be a discriminant for the association with Env. Binding stability to ß2m may confer to HLA-C the ability to preferentially act either as a conventional immune-competent molecule or as an accessory molecule involved in HIV-1 infectivity.
Assuntos
Membrana Celular/virologia , Infecções por HIV/virologia , HIV-1/crescimento & desenvolvimento , Antígenos HLA-C/metabolismo , Interações Hospedeiro-Patógeno , Microglobulina beta-2/metabolismo , Produtos do Gene env do Vírus da Imunodeficiência Humana/metabolismo , Células HEK293 , Células HeLa , Humanos , Ligação ProteicaRESUMO
BACKGROUND: Combined antiretroviral therapy has drastically reduced mortality and morbidity of HIV-infected individuals. Nevertheless long-term toxicity and appearance of viral resistance hampers the prolonged effectiveness of combination therapy, requiring a continuous input of drugs to replace those utilized in combination regimens. We here investigated the anti-HIV activity of novel derivatives of the suradista chemical class. METHODS: Compounds were tested on acute HIV-1 infection of activated peripheral blood mononuclear cells. HIV production was monitored by enzyme-linked immunosorbent assay measuring the protein p24 released in culture supernatants. Fusion assays were carried out to study the mechanism of action of these compounds. A modified version of a previously established recombinant vaccinia virus-based assay was used measuring activation of a reporter gene upon fusion of two distinct cell populations. Flow cytometry was performed in competition assays for the binding of several antibodies targeting different sites of the viral envelope glycoprotein gp120, or the receptor CD4, or the coreceptors CXCR4 and CCR5. RESULTS: Four compounds inhibited replication of a prototypic R5 (BaL) and X4 (IIIB) laboratory-adapted HIV-1 strain at low micromolar concentrations, in the absence of cytotoxicity. Approximately a ten fold greater activity was achieved against the X4 as compared to the R5 strain. The compounds blocked X4 and R5 HIV-1 fusion, a step of viral entry. This activity appeared specific for HIV-1, as entry of human herpesvirus 6 (HHV-6) and influenza virus was not substantially affected. Further investigation of the inhibitory mechanism revealed that these new molecules target the viral envelope, rather than the coreceptors, as previously shown for a congener of the same class characterized by a long plasmatic half-life. Indeed ND-4043, the most active compound, specifically competed with binding of monoclonal antibodies against the CD4-binding site (CD4-BS) and coreceptor-binding site (CoR-BS) of gp120. These compounds displayed broad anti-HIV activity, as they inhibited various primary R5, X4 and, importantly, dualtropic R5X4 HIV-1 isolates. Of the four derivatives tested, the dimeric compounds were consistently more potent than the monomeric ones. CONCLUSIONS: Given their unique features, these molecules represent promising candidates for further development and exploitation as anti-HIV therapeutics.
Assuntos
Inibidores da Fusão de HIV/farmacologia , HIV-1/fisiologia , Internalização do Vírus/efeitos dos fármacos , Células 3T3 , Animais , Antivirais/farmacologia , Benzilaminas , Morte Celular/efeitos dos fármacos , Linhagem Celular , Ciclamos , Cicloexanos/farmacologia , Citometria de Fluxo , Proteína gp120 do Envelope de HIV/metabolismo , Infecções por HIV/patologia , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , Compostos Heterocíclicos/farmacologia , Humanos , Maraviroc , Fusão de Membrana/efeitos dos fármacos , Camundongos , Receptores CCR5/metabolismo , Receptores CXCR4/metabolismo , Triazóis/farmacologia , Replicação Viral/efeitos dos fármacosRESUMO
Apps et al. (Reports, 5 April 2013, p. 87) found that high human leukocyte antigen C (HLA-C) expression favors HIV-1 control. However, as noted here, HLA-C was assessed with a monoclonal antibody (DT9) that cross-reacts with HLA-E. In the context of the available evidence, this is consistent with the idea that the two leukocyte antigens collaborate to keep the HIV-1 virus at bay.
Assuntos
Regulação da Expressão Gênica , Infecções por HIV/genética , Infecções por HIV/imunologia , HIV/imunologia , Antígenos HLA-C/genética , Linfócitos T Citotóxicos/imunologia , HumanosRESUMO
BACKGROUND: Ten to 30% of HIV-1 infected subjects develop broadly neutralizing antibodies (bNAbs) during chronic infection. We hypothesized that immunizing rabbits with viral envelope glycoproteins (Envs) from these patients may induce bNAbs, when formulated as a trimeric protein and in the presence of an adjuvant. METHODS: Based on in vitro neutralizing activity in serum, patients with bNAbs were selected for cloning of their HIV-1 Env. Seven stable soluble trimeric gp140 proteins were generated from sequences derived from four adults and two children infected with either clade A or B HIV-1. From one of the clade A Envs both the monomeric and trimeric Env were produced for comparison. Rabbits were immunized with soluble gp120 or trimeric gp140 proteins in combination with the adjuvant dimethyl dioctadecyl ammonium/trehalose dibehenate (CAF01). Env binding in rabbit immune serum was determined using ELISAs based on gp120-IIIB protein. Neutralizing activity of IgG purified from rabbit immune sera was measured with the pseudovirus-TZMbl assay and a PBMC-based neutralization assay for selected experiments. RESULTS: It was initially established that gp140 trimers induce better antibody responses over gp120 monomers and that the adjuvant CAF01 was necessary for such strong responses. Gp140 trimers, based on HIV-1 variants from patients with bNAbs, were able to elicit both gp120IIIB specific IgG and NAbs to Tier 1 viruses of different subtypes. Potency of NAbs closely correlated with titers, and an gp120-binding IgG titer above a threshold of 100,000 was predictive of neutralization capability. Finally, peptide inhibition experiments showed that a large fraction of the neutralizing IgG was directed against the gp120 V3 region. CONCLUSIONS: Our results indicate that the strategy of reverse immunology based on selected Env sequences is promising when immunogens are delivered as stabilized trimers in CAF01 adjuvant and that the rabbit is a valuable model for HIV vaccine studies.
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Proteína gp120 do Envelope de HIV/química , Proteína gp120 do Envelope de HIV/imunologia , HIV-1/imunologia , Multimerização Proteica , Vacinação , Produtos do Gene env do Vírus da Imunodeficiência Humana/química , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Química Farmacêutica , Feminino , Humanos , Cinética , Masculino , Modelos Animais , Fragmentos de Peptídeos/imunologia , Estrutura Quaternária de Proteína , CoelhosRESUMO
Trimeric soluble forms of HIV gp140 envelope glycoproteins represent one of the closest molecular structures compared to native spikes present on intact virus particles. Trimeric soluble gp140 have been generated by several groups and such molecules have been shown to induce antibodies with neutralizing activity against homologous and heterologous viruses. In the present study, we generated a recombinant trimeric soluble gp140, derived from a previously identified Ugandan A-clade HIV field isolate (gp14094UG018). Antibodies elicited in immunized rabbits show a broad binding pattern to HIV envelopes of different clades. An epitope mapping analysis reveals that, on average, the binding is mostly focused on the C1, C2, V3, V5 and C5 regions. Immune sera show neutralization activity to Tier 1 isolates of different clades, demonstrating cross clade neutralizing activity which needs to be further broadened by possible structural modifications of the clade A gp14094UG018. Our results provide a rationale for the design and evaluation of immunogens and the clade A gp14094UG018 shows promising characteristics for potential involvement in an effective HIV vaccine with broad activity.
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Infecções por HIV/imunologia , Imunidade Humoral , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Ensaio de Imunoadsorção Enzimática , Epitopos de Linfócito B/imunologia , Feminino , Células HEK293 , Infecções por HIV/virologia , HIV-1/classificação , Humanos , Imunização , Testes de Neutralização , Coelhos , Proteínas Recombinantes/imunologia , UgandaRESUMO
HIV-1 DNA vaccines have many advantageous features. Evaluation of HIV-1 vaccine candidates often starts in small animal models before macaque and human trials. Here, we selected and optimized DNA vaccine candidates through systematic testing in rabbits for the induction of broadly neutralizing antibodies (bNAb). We compared three different animal models: guinea pigs, rabbits and cynomolgus macaques. Envelope genes from the prototype isolate HIV-1 Bx08 and two elite neutralizers were included. Codon-optimized genes, encoded secreted gp140 or membrane bound gp150, were modified for expression of stabilized soluble trimer gene products, and delivered individually or mixed. Specific IgG after repeated i.d. inoculations with electroporation confirmed in vivo expression and immunogenicity. Evaluations of rabbits and guinea pigs displayed similar results. The superior DNA construct in rabbits was a trivalent mix of non-modified codon-optimized gp140 envelope genes. Despite NAb responses with some potency and breadth in guinea pigs and rabbits, the DNA vaccinated macaques displayed less bNAb activity. It was concluded that a trivalent mix of non-modified gp140 genes from rationally selected clinical isolates was, in this study, the best option to induce high and broad NAb in the rabbit model, but this optimization does not directly translate into similar responses in cynomolgus macaques.
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The natural history of HIV-1 infection is highly variable in different individuals, spanning from a rapidly progressive course to a long-term asymptomatic infection. A major determinant of the pace of disease progression is the in vivo level of HIV-1 replication, which is regulated by a complex network of cytokines and chemokines expressed by immune and inflammatory cells. The chemokine system is critically involved in the control of HIV-1 replication by virtue of the role played by specific chemokine receptors, most notably CCR5 and CXCR4, as cell-surface coreceptors for HIV-1 entry; hence, the chemokines that naturally bind such coreceptors act as endogenous inhibitors of HIV-1. Here, we show that the CXC chemokine CXCL4 (PF-4), the most abundant protein contained within the α-granules of platelets, is a broad-spectrum inhibitor of HIV-1 infection. Unlike other known HIV-suppressive chemokines, CXCL4 inhibits infection by the majority of primary HIV-1 isolates regardless of their coreceptor-usage phenotype or genetic subtype. Consistent with the lack of viral phenotype specificity, blockade of HIV-1 infection occurs at the level of virus attachment and entry via a unique mechanism that involves direct interaction of CXCL4 with the major viral envelope glycoprotein, gp120. The binding site for CXCL4 was mapped to a region of the gp120 outer domain proximal to the CD4-binding site. The identification of a platelet-derived chemokine as an endogenous antiviral factor may have relevance for the pathogenesis and treatment of HIV-1 infection.
Assuntos
Plaquetas/metabolismo , HIV-1/fisiologia , Fator Plaquetário 4/fisiologia , Células Cultivadas , Humanos , Fusão de Membrana/fisiologia , Fator Plaquetário 4/metabolismo , Replicação ViralRESUMO
BACKGROUND: Long-term survival of HIV-1 infected individuals is usually achieved by continuous administration of combination antiretroviral therapy (ART). An exception to this scenario is represented by HIV-1 infected nonprogressors (NP) which maintain relatively high circulating CD4+ T cells without clinical symptoms for several years in the absence of ART. Several lines of evidence indicate an important role of the T-cell response in the modulation of HIV-1 infection during the acute and chronic phase of the disease. RESULTS: We analyzed the functional and the differentiation phenotype of Nef- and Tat-specific CD8+ T cells in a cohort of HIV-1 infected NP in comparison to progressors, ART-treated seropositive individuals and individuals undergoing a single cycle of ART interruption. We observed that a distinctive feature of NP is the presence of Nef-specific CD45RA+ CD8+ T cells secreting MIP-1beta but not IFN-gamma. This population was present in 7 out of 11 NP. CD45RA+ IFN-gammaneg MIP-1beta+ CD8+ T cells were not detected in HIV-1 infected individuals under ART or withdrawing from ART and experiencing a rebounding viral replication. In addition, we detected Nef-specific CD45RA+ IFN-gammaneg MIP-1beta+ CD8+ T cells in only 1 out of 10 HIV-1 infected individuals with untreated progressive disease. CONCLUSION: The novel antigen-specific CD45RA+ IFN-gammaneg MIP-1beta+ CD8+ T cell population represents a new candidate marker of long-term natural control of HIV-1 disease progression and a relevant functional T-cell subset in the evaluation of the immune responses induced by candidate HIV-1 vaccines.
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EUROPRISE is a Network of Excellence sponsored from 2007 to 2011 by the European Commission within the 6th Framework Program. The Network encompasses a wide portfolio of activities ranging from an integrated research program in the field of HIV vaccines and microbicides to training, dissemination and advocacy. The research program covers the whole pipeline of vaccine and microbicide development from discovery to early clinical trials. The Network is composed of 58 partners representing more than 65 institutions from 13 European countries; it also includes three major pharmaceutical companies (GlaxoSmithKline, Novartis and Sanofi-Pasteur) involved in HIV microbicide and vaccine research. The Network displays a dedicated and informative web page: http://www.europrise.org. Finally, a distinguishing trait of EUROPRISE is its PhD School of students from across Europe, a unique example in the world of science aimed at spreading excellence through training. EUROPRISE held its second annual conference in Budapest in November, 2009. The conference had 143 participants and their presentations covered aspects of vaccine and microbicide research, development and discovery. Since training is a major task of the Network, the students of the EUROPRISE PhD program summarized certain presentations and their view of the conference in this paper.
Assuntos
Vacinas contra a AIDS/imunologia , Anti-Infecciosos/síntese química , Desenho de Fármacos , Imunidade Adaptativa/imunologia , Animais , Ensaios Clínicos como Assunto , Suscetibilidade a Doenças , Europa (Continente) , Infecções por HIV/imunologia , HIV-1/imunologia , Humanos , Imunidade nas Mucosas/imunologia , Camundongos , Testes de NeutralizaçãoRESUMO
INTRODUCTION: There seem to be no published data concerning the clinical impact of populations of hepatitis B virus (HBV) in the hepatic and extrahepatic compartments of HIV-infected people with severe acute hepatitis. CASE PRESENTATION: A 26-year-old Caucasian man presenting to our hospital with clinical symptoms suggesting acute hepatitis was found to have an acute hepatitis B profile upon admission. He developed fatal fulminant hepatitis and was found to be heavily immunocompromised due to HIV-1 infection. He had a high plasma HBV and HIV load, and analysis of the partial pre-S1/pre-S2 domain showed the presence of mixed infection with D and F genotypes. Analysis of the point mutations within this region revealed the presence of HBV strains with amino acid substitutions at the immunodominant epitopes involved in B or T cell recognition. A homogeneous population of a pre-core mutant strain harbouring the A1896G and A1899G affecting HBeAg expression was invariably found in the liver tissue, plasma and peripheral blood mononuclear cells despite active HBeAg secretion; it was the dominant strain in the liver only, and was characterised by the presence of two point mutations in the direct repeat 1 domain involved in HBV replication activity. Taken together, these mutations are indicative of a highly replicative virus capable of evading immune responses. CONCLUSION: This case report provides clinical evidence of a possible association between the rapid spread of highly replicative escape mutants and the development of fulminant hepatitis in a heavily immunocompromised patient. Virological surveillance of severe acute hepatitis B may be important in establishing an early treatment strategy involving antiviral drugs capable of preventing liver failure, especially in individuals for whom liver transplantation is not accepted as a standard indication.
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The chemokine receptor CXCR3 is involved in cell trafficking dysregulation associated with several inflammatory conditions, including autoimmune and viral diseases. Downregulation of CXCR3, through binding with its ligand CXCL11 (I-TAC), represents a key mechanism in lymphocyte recruitment. Determination of circulating I-TAC can provide useful information in the investigation of inflammatory/infectious conditions. The existing commercial kit does not measure CXCL11/I-TAC in complex matrices, such as human plasma and serum, as reliably as in in vitro-generated cell culture supernatants. We here describe means which lead to an improvement of CXCL11/I-TAC measurement in human plasma and serum.