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1.
PLoS One ; 19(7): e0288895, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38976697

RESUMO

To assess whether biomarkers of systemic inflammation are associated with HIV acquisition or with the timing of ART initiation ("immediate", at diagnosis, versus "deferred", at 24 weeks post-diagnosis) in men-who-have-sex-with-men (MSM) and transgender women, we conducted a retrospective study comparing inflammatory biomarkers in participants' specimens collected before infection and after ≥2 years of effective ART. We measured biomarkers in four longitudinally collected plasma, including two specimens collected from each participant before and two after HIV acquisition and confirmed ART-suppression. Biomarkers were quantified by enzyme-linked immuno-assay or Meso Scale Discovery. When evaluating systematic variation in these markers over time, we found that multiple biomarkers consistently varied across participants' two pre-infection or two post-ART-suppression specimens. Additionally, we compared changes in biomarkers after vs before HIV acquisition. Across 47 participants, the levels of C-reactive protein (CRP), monocyte chemo-attractant protein-1, tumor necrosis factor-α and interferon gamma-induced protein-10 significantly increased while leptin and lipopolysaccharide binding protein (LBP) significantly decreased following HIV infection. Randomization to deferred-ART initiation was associated with greater increases in CRP and no decrease in LBP. Acquisition of HIV appeared to induce systemic inflammation, with elevation of biomarkers previously associated with infections and cardiovascular disease. Initiation of ART during the early weeks of infection tempered the increase in pro-inflammatory biomarkers compared to delaying ART for ~24 weeks after HIV diagnosis. These findings provide insight into potential mediators by which immediate-ART initiation improves health outcomes, perhaps because immediate-ART limits the size of the HIV reservoir or limits immune dysregulation that in turn trigger systemic inflammation.


Assuntos
Biomarcadores , Infecções por HIV , Humanos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Infecções por HIV/sangue , Masculino , Biomarcadores/sangue , Feminino , Adulto , Estudos Retrospectivos , Inflamação/sangue , Pessoa de Meia-Idade , Proteínas de Fase Aguda/metabolismo , Proteína C-Reativa/metabolismo , Proteína C-Reativa/análise , Fármacos Anti-HIV/uso terapêutico , Pessoas Transgênero , Proteínas de Transporte , Glicoproteínas de Membrana
2.
medRxiv ; 2023 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-37461626

RESUMO

Objective: Assess whether biomarkers of systemic inflammation are associated with HIV acquisition or with the timing of ART initiation ("immediate", at diagnosis, versus "deferred", at 24 weeks post-diagnosis) in men-who-have-sex-with-men (MSM) and transgender women. Design: A retrospective study comparing inflammatory biomarkers in participants' specimens collected before and after ≥2 years of effective ART. Methods: Inflammatory biomarkers were measured in four longitudinally collected plasma specimens, including two plasma specimens collected from each participant before and two after HIV acquisition and confirmed ART-suppression. Biomarkers were quantified by enzyme-linked immuno-assay or Meso Scale Discovery. Statistical measures compared intra-participant and between-group changes in biomarkers. Results: Across 50 participants, the levels of C-reactive protein (CRP), monocyte chemo-attractant protein-1, tumor necrosis factor-α and interferon gamma-induced protein-10 significantly increased while leptin and lipopolysaccharide binding protein (LBP) significantly decreased following HIV infection. Randomization to deferred-ART initiation was associated with greater increases in CRP and no decreases in LBP. Multiple biomarkers varied significantly within participants' two pre-infection or two post-ART-suppression specimens. Conclusions: Acquisition of HIV appeared to induce systemic inflammation, with elevation of biomarkers previously associated with infections and cardiovascular disease. Initiation of ART during the early weeks of infection tempered the increase in pro-inflammatory biomarkers compared to those who delayed ART for ~24 weeks after HIV diagnosis, perhaps because immediate-ART limited the size of the HIV reservoir or limited immune dysregulation. Some but not all biomarkers appeared sufficiently stable to assess intraparticipant changes over time. Given that pro-inflammatory biomarkers predict multiple co-morbidities, our findings suggest that immediate-ART initiation may improve health outcomes.

3.
J Acquir Immune Defic Syndr ; 89(4): 462-471, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34897226

RESUMO

BACKGROUND: Alcohol use disorders (AUDs) are common in men who have sex with men (MSM) and transgender women (TGW) in Peru and undermine antiretroviral therapy (ART) adherence. Oral naltrexone (NTX) is an evidence-based treatment for AUD that has not been assessed in cotreating AUD in MSM/TGW with HIV. SETTING AND DESIGN: A multi-site, randomized, double-blind, placebo-controlled trial among MSM/TGW with AUD and newly diagnosed with HIV in Lima, Peru. METHODS: Newly diagnosed MSM/TGW with HIV and AUD were prescribed a single-treatment regimen of EFV/TDF/FTC from 2014 to 2015 and randomized 2:1 to oral NTX (N = 103) or placebo (N = 53) for 24 weeks. The primary and secondary outcomes were proportion achieving viral suppression (VS: HIV-1 RNA < 400 copies/mL) or maximal viral suppression (MVS: HIV-1 RNA < 40 copies/mL) at 24 weeks. RESULTS: There were no significant differences between the arms in VS (81.6% NTX arm vs 75.5% placebo arm; P = 0.37) or MVS (61.2% NTX arm vs 66.0% placebo arm; P = 0.48). Adherence to study medication was low (mean = 34.6%) overall with only 21.4% of participants meeting recommended adherence levels (≥80% daily doses/month). Participants allocated to NTX had significantly lower adherence compared with placebo for both the first and second 12-week study periods, respectively (44.0% vs 35.2%, P = 0.04; 31.4% vs 35.2%, P = 0.03). CONCLUSIONS: Findings are inconclusive regarding the use of NTX for treatment of AUD in MSM/TGW newly diagnosed with HIV. VS and MVS levels were high irrespective of allocation. Adherence to study medication was low, requiring further exploration of strategies to optimize adherence to NTX as AUD treatment.


Assuntos
Alcoolismo , Infecções por HIV , Minorias Sexuais e de Gênero , Pessoas Transgênero , Alcoolismo/complicações , Alcoolismo/tratamento farmacológico , Feminino , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Homossexualidade Masculina , Humanos , Masculino , Naltrexona/uso terapêutico , Peru
4.
Sex Transm Dis ; 47(12): 825-831, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33186338

RESUMO

BACKGROUND: We assessed sexual behavior and incidence of sexually transmitted infections (STIs) among men who have sex with men and transgender women participating in Sabes, a study of an expanded treatment as prevention strategy focused on early diagnosis and treatment of HIV infection in Lima, Peru (2013-2017). METHODS: Sabes participants were tested monthly for HIV to identify acute or early infections, and HIV-positive participants were randomized to receive antiretroviral therapy immediately (immediate arm) or after 24 weeks (deferred arm) during a 48-week follow-up period. Sexual behavior was assessed at randomization (baseline) and every 12 weeks thereafter. Participants were tested for urethral and rectal chlamydia and gonorrhea and for syphilis at baseline, 12, 24, and 48 weeks. We describe patterns of sexual behavior during the 48-week follow-up period and compare sexual behavior and STI incidence between study arms. RESULTS: After randomization, 207 HIV-positive participants completed questionnaires and STI testing at 2 or more visits. After HIV diagnosis, participants in both arms reported increases in condom use with main and casual partners and decreased drug and alcohol use before or during anal sex. We observed no between-arm differences in sexual behavior. Deferred arm participants had higher incidence of chlamydia (incidence rate ratio, 2.33; 95% confidence interval, 1.14-4.77) but not gonorrhea or syphilis. CONCLUSIONS: Despite reported increases in condom use, the overall high incidence of STIs reflects some ongoing condomless sex among HIV-positive men who have sex with men and transgender women, highlighting the importance of regular STI screening and counseling to support consistent condom use among HIV-positive individuals at risk for STIs.


Assuntos
Terapia Antirretroviral de Alta Atividade/métodos , Infecções por HIV/tratamento farmacológico , Homossexualidade Masculina/psicologia , Comportamento Sexual/estatística & dados numéricos , Pessoas Transgênero/psicologia , Adulto , Feminino , Infecções por HIV/epidemiologia , Homossexualidade Masculina/estatística & dados numéricos , Humanos , Masculino , Peru/epidemiologia , Parceiros Sexuais , Minorias Sexuais e de Gênero , Infecções Sexualmente Transmissíveis/epidemiologia , Pessoas Transgênero/estatística & dados numéricos
5.
PLoS One ; 14(9): e0222114, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31525225

RESUMO

BACKGROUND: In Peru, there is an ongoing high-incidence HIV epidemic among men who have sex with men (MSM) and transgender women (TW). Sexual concurrency, or having sex with a partner in between two acts of sex with another partner, may be a key factor in onward HIV transmission. In this study, we quantify concurrency, evaluate factors associated with concurrency, and assess condom use with concurrent partners among MSM and TW in Peru. METHODS: We conducted a secondary analysis of data from the 2011 Peruvian Biobehavioral Survey. Pearson's Chi-squared test was used to identify individual-level characteristics associated with concurrency. We estimated the association between participant characteristics, concurrent partnerships, partnership type (stable vs. non-stable), and CLAI within the context of concurrent partnerships using multivariate and repeated-measure Poisson regression. RESULTS: 3-month cumulative prevalence of concurrency was higher among TW compared to MSM (30.7% vs 25.2%, p = 0.014). Among those with concurrent stable and non-stable partners, 45% used condoms with both partners (95% CI: 40%-50%) and 30% preferentially had CLAI with the stable partner only (95%CI: 26%-35%). Factors associated with CLAI within the context of concurrent partnerships varied between MSM and TW. CONCLUSIONS: Although concurrency is common among TW and MSM in Peru, patterns of concurrency and differential condom use may vary between TW and MSM. Future research may explore differential condom use with stable and non-stable partners to better understand behavioral factors that may alter vulnerability to HIV in TW compared to MSM.


Assuntos
Preservativos/estatística & dados numéricos , Homossexualidade Masculina , Sexo Seguro/estatística & dados numéricos , Pessoas Transgênero , Adolescente , Adulto , Utilização de Equipamentos e Suprimentos/estatística & dados numéricos , Feminino , Humanos , Masculino , Peru
6.
AIDS Care ; 31(7): 848-856, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30616376

RESUMO

A substantial body of literature has characterized how psychosocial factors, including HIV-related stigma and coping, are associated with HIV testing and HIV care utilization post-diagnosis. Less is known about if certain psychosocial characteristics pre-diagnosis may also predict linkage to care among individuals who receive an HIV-positive diagnosis. We examined if pre-diagnosis awareness/perception about HIV-related stigma and dispositional coping styles predicted linkage to HIV care within three months post-diagnosis with a secondary analysis of 604 patients from a randomized controlled trial (Sabes Study). Awareness/perception about HIV-related stigma, dispositional maladaptive and adaptive coping were measured before patients underwent an HIV test. Linkage to care was measured as receipt of care within three months of receiving the diagnosis. After adjusting for covariates, individuals who reported greater dispositional maladaptive coping pre-diagnosis had lower odds of linking to care, OR = 0.82, 95%CI [0.67, 1.00], p = .05. There was also a non-significant inverse association between dispositional adaptive coping pre-diagnosis and linkage to care. These preliminary data suggest the need for further longitudinal research and highlight the potential utility of pre-diagnosis psychosocial assessment and tailored counseling when providing positive HIV diagnosis results.


Assuntos
Adaptação Psicológica , Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Estigma Social , Adulto , Conscientização , Feminino , Infecções por HIV/etnologia , Infecções por HIV/psicologia , Humanos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Percepção , Peru , Ensaios Clínicos Controlados Aleatórios como Assunto
7.
JCI Insight ; 2(24)2017 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-29263306

RESUMO

Accurate HIV-1 incidence estimation is critical to the success of HIV-1 prevention strategies. Current assays are limited by high false recent rates (FRRs) in certain populations and a short mean duration of recent infection (MDRI). Dynamic early HIV-1 antibody response kinetics were harnessed to identify biomarkers for improved incidence assays. We conducted retrospective analyses on circulating antibodies from known recent and longstanding infections and evaluated binding and avidity measurements of Env and non-Env antigens and multiple antibody forms (i.e., IgG, IgA, IgG3, IgG4, dIgA, and IgM) in a diverse panel of 164 HIV-1-infected participants (clades A, B, C). Discriminant function analysis identified an optimal set of measurements that were subsequently evaluated in a 324-specimen blinded biomarker validation panel. These biomarkers included clade C gp140 IgG3, transmitted/founder clade C gp140 IgG4 avidity, clade B gp140 IgG4 avidity, and gp41 immunodominant region IgG avidity. MDRI was estimated at 215 day or alternatively, 267 days. FRRs in untreated and treated subjects were 5.0% and 3.6%, respectively. Thus, computational analysis of dynamic HIV-1 antibody isotype and antigen interactions during infection enabled design of a promising HIV-1 recency assay for improved cross-sectional incidence estimation.


Assuntos
Anticorpos Anti-HIV/sangue , Infecções por HIV/diagnóstico , HIV-1/imunologia , Afinidade de Anticorpos/imunologia , Reações Antígeno-Anticorpo/imunologia , Biomarcadores/sangue , Biologia Computacional/métodos , Antígenos HIV/imunologia , Infecções por HIV/epidemiologia , Infecções por HIV/imunologia , Humanos , Imunoglobulina G/imunologia , Incidência , Estudos Retrospectivos , Fatores de Tempo
8.
Subst Use Misuse ; 52(7): 831-839, 2017 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-28426357

RESUMO

BACKGROUND: Peruvian men who have sex with men (MSM) and transgender women (TGW) experience the double burden of a highly concentrated HIV epidemic with a high prevalence of alcohol use disorders (AUDs). Recent research has associated both with risky sexual behaviors, including unprotected sex, having multiple sexual partners, engaging in sex work, having recent sexually transmitted infections, and having HIV-infected partners. AUDs have also been associated in MSM/TGW with being unaware of HIV+ status. OBJECTIVES: This study aims to further examine issues associated with alcohol consumption, HIV infection, and risk behaviors in a qualitative analysis of focus groups conducted with MSM/TGW in Peru. METHODS: A total of 26 MSM/TGW participants with AUDs participated in three semi-structured focus groups in Lima, Peru. Content analysis was facilitated by software, and specific themes were elucidated. RESULTS: Participants described their drinking patterns, including the types of alcoholic drinks they consumed. They depicted drinking frequently and over multiple-day sessions. Problematic drinking behaviors were described, as well as the perceived characteristics of alcohol dependence. Interestingly, HIV-infected participants who were prescribed antiretroviral therapy did not believe that their drinking affected their medication adherence. These insights can aid in the design of future interventions aiming to reduce problematic drinking as well as HIV-related risk behaviors and, subsequently, HIV incidence. CONCLUSIONS: Peruvian MSM/TGW exhibit problematic drinking, which may be associated with risky sexual behaviors and HIV transmission. Interest in reducing alcohol consumption was high, suggesting the need for targeted behavioral and pharmacological interventions.


Assuntos
Consumo de Bebidas Alcoólicas/psicologia , Transtornos Relacionados ao Uso de Álcool/psicologia , Infecções por HIV/psicologia , Homossexualidade Masculina/psicologia , Pessoas Transgênero/psicologia , Sexo sem Proteção/psicologia , Adulto , Transtornos Relacionados ao Uso de Álcool/complicações , Feminino , Grupos Focais , Infecções por HIV/complicações , Humanos , Masculino , Adesão à Medicação/psicologia , Peru , Adulto Jovem
9.
Am J Mens Health ; 11(4): 1269-1278, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-25787988

RESUMO

In Peru, the HIV epidemic is concentrated in men who have sex with men (MSM) and transgender women (TGW). Multiple studies correlate alcohol use disorders (AUDs) with risky sexual behaviors among Peruvian MSM. Qualitative research was used to inform a clinical trial on the acceptability of medication-assisted therapies to assist management of AUDs and improve antiretroviral therapy (ART) adherence among MSM/TGW in Peru. Three focus groups involving HIV-infected or HIV-uninfected MSM/TGW ( n = 26) with AUDs (AUDIT ≥ 8) were transcribed, translated from Spanish into English, and analyzed using thematic content analysis. Despite having an AUD, participants considered themselves "social" drinkers, minimized their drinking behaviors, and differed about whether or not alcohol problems could be treated. Participants expressed skepticism about medication for treating AUDs. Three concepts emerged as necessary components of a treatment program for alcohol problems: cost, family support, and the potential to drink less alcohol without attaining total abstinence. This study reveals important areas of education to increase potential acceptability of a medication for treating AUDs among MSM/TGW. Given the social conditions and knowledge base of the participants, medication-assisted therapies using naltrexone may be a beneficial strategy for MSM with AUDs.


Assuntos
Alcoolismo/tratamento farmacológico , Homossexualidade Masculina , Naltrexona/uso terapêutico , Antagonistas de Entorpecentes/uso terapêutico , Aceitação pelo Paciente de Cuidados de Saúde , Adulto , Grupos Focais , Humanos , Masculino , Peru
10.
Proc Natl Acad Sci U S A ; 109(50): E3503-12, 2012 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-23151505

RESUMO

To better understand how innate immune responses to vaccination can lead to lasting protective immunity, we used a systems approach to define immune signatures in humans over 1 wk following MRKAd5/HIV vaccination that predicted subsequent HIV-specific T-cell responses. Within 24 h, striking increases in peripheral blood mononuclear cell gene expression associated with inflammation, IFN response, and myeloid cell trafficking occurred, and lymphocyte-specific transcripts decreased. These alterations were corroborated by marked serum inflammatory cytokine elevations and egress of circulating lymphocytes. Responses of vaccinees with preexisting adenovirus serotype 5 (Ad5) neutralizing antibodies were strongly attenuated, suggesting that enhanced HIV acquisition in Ad5-seropositive subgroups in the Step Study may relate to the lack of appropriate innate activation rather than to increased systemic immune activation. Importantly, patterns of chemoattractant cytokine responses at 24 h and alterations in 209 peripheral blood mononuclear cell transcripts at 72 h were predictive of subsequent induction and magnitude of HIV-specific CD8(+) T-cell responses. This systems approach provides a framework to compare innate responses induced by vectors, as shown here by contrasting the more rapid, robust response to MRKAd5/HIV with that to yellow fever vaccine. When applied iteratively, the findings may permit selection of HIV vaccine candidates eliciting innate immune response profiles more likely to drive HIV protective immunity.


Assuntos
Vacinas contra a AIDS/imunologia , Adenovírus Humanos/imunologia , Linfócitos T CD8-Positivos/imunologia , Vacinas contra a AIDS/genética , Adenovírus Humanos/genética , Adenovírus Humanos/fisiologia , Adulto , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Quimiocinas/sangue , Citocinas/sangue , Feminino , Vetores Genéticos , Infecções por HIV/imunologia , Infecções por HIV/prevenção & controle , Humanos , Imunidade Inata , Mediadores da Inflamação/sangue , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Biologia de Sistemas , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia , Replicação Viral , Vacina contra Febre Amarela/imunologia , Adulto Jovem
11.
J Virol ; 84(1): 630-8, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19846512

RESUMO

A recent clinical trial of a T-cell-based AIDS vaccine delivered with recombinant adenovirus type 5 (rAd5) vectors showed no efficacy in lowering viral load and was associated with increased risk of human immunodeficiency virus type 1 (HIV-1) infection. Preexisting immunity to Ad5 in humans could therefore affect both immunogenicity and vaccine efficacy. We hypothesized that vaccine-induced immunity is differentially affected, depending on whether subjects were exposed to Ad5 by natural infection or by vaccination. Serum samples from vaccine trial subjects receiving a DNA/rAd5 AIDS vaccine with or without prior immunity to Ad5 were examined for the specificity of their Ad5 neutralizing antibodies and their effect on HIV-1 immune responses. Here, we report that rAd5 neutralizing antibodies were directed to different components of the virion, depending on whether they were elicited by natural infection or vaccination in HIV vaccine trial subjects. Neutralizing antibodies elicited by natural infection were directed largely to the Ad5 fiber, while exposure to rAd5 through vaccination elicited antibodies primarily to capsid proteins other than fiber. Notably, preexisting immunity to Ad5 fiber from natural infection significantly reduced the CD4 and CD8 cell responses to HIV Gag after DNA/rAd5 vaccination. The specificity of Ad5 neutralizing antibodies therefore differs depending on the route of exposure, and natural Ad5 infection compromises Ad5 vaccine-induced immunity to weak immunogens, such as HIV-1 Gag. These results have implications for future AIDS vaccine trials and the design of next-generation gene-based vaccine vectors.


Assuntos
Vacinas contra a AIDS , Infecções por Adenoviridae/imunologia , Adenoviridae/imunologia , Anticorpos Neutralizantes/imunologia , Especificidade de Anticorpos , Vetores Genéticos , Imunização , Antígenos Virais/imunologia , Epitopos , Produtos do Gene gag/imunologia , Produtos do Gene gag/uso terapêutico , Proteínas do Vírus da Imunodeficiência Humana/imunologia , Proteínas do Vírus da Imunodeficiência Humana/uso terapêutico , Humanos
12.
Am J Reprod Immunol ; 61(2): 121-9, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19143675

RESUMO

OBJECTIVE: Diaphragms are being considered for use with vaginal microbicide gels to provide enhanced protection against sexually transmitted pathogens. The purpose of this study was to determine whether use of a diaphragm with microbicide or placebo gel causes cervicovaginal inflammation or perturbations in cervicovaginal immune defense. METHOD OF STUDY: Eighty-one non-pregnant women were randomized into three groups and instructed to use Milex (CooperSurgical, Inc., Trumbull, CT, USA)diaphragms overnight for 14 days in combination with one of the two acid-buffering microbicide gels [ACIDFORM (Instead Inc., La Jolla, CA, USA) or BufferGel(trade mark) (BG; ReProtect Inc., Baltimore, Maryland)] or placebo gel (K-Y Jelly); Personal Products Inc., Raritan, NJ, USA). Cervicovaginal lavages (CVLs) were performed prior to study entry and on days 8 and 16. Nine soluble mediators of vaginal inflammation or immune defense were measured in CVLs by Bio-Plex or ELISA. RESULTS: Use of diaphragms with placebo or microbicide gel was not associated with increased levels of inflammation markers. Concentrations of secretory leukocyte protease inhibitor (SLPI) were markedly reduced in the BG group. CONCLUSION: Daily use of a diaphragm with placebo or acidifying microbicide gel did not cause cervicovaginal inflammation. However, diaphragm/BG use was associated with markedly reduced levels of SLPI, an important mediator of innate immune defense. Further studies are warranted to establish the safety of diaphragm/microbicide gel combinations.


Assuntos
Anti-Infecciosos Locais/efeitos adversos , Anti-Infecciosos Locais/farmacologia , Dispositivos Anticoncepcionais Femininos , Imunidade Inata/efeitos dos fármacos , Inflamação/imunologia , Cremes, Espumas e Géis Vaginais/efeitos adversos , Adolescente , Adulto , Biomarcadores/análise , Citocinas/análise , Feminino , Humanos , Pessoa de Meia-Idade , Cremes, Espumas e Géis Vaginais/administração & dosagem , Adulto Jovem
13.
Vaccine ; 24(47-48): 6893-904, 2006 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-16890329

RESUMO

Dozens of human immunodeficiency virus-type 1 (HIV-1) vaccine candidates specifically designed to elicit cytotoxic T-lymphocyte (CTL) responses have entered the pipeline of clinical trials. Evaluating the immunogenicity and potential efficacy of these HIV-1 vaccine candidates is challenging in the face of the extensive viral genetic diversity of circulating strains. Standardized peptide reagents to define the magnitude and potential breadth of the T-cell response, especially to circulating strains of HIV-1, are needed. For this purpose we developed a biometric approach based on T-cell recognition pattern for defining standardized reagents. Circulating strains in the Los Alamos database were evaluated and standardized algorithms to define all potential T-cell epitopes (PTEs) were generated. While many unique PTEs could be identified, a finite number based upon prevalence of circulating strains in the database, which we define as vaccine-important PTEs (VIPs), were used to select a common standardized panel of HIV-1 peptides for CTL-based vaccine evaluation. The usability of PTE peptide set was manifested by detection of Nef-specific CTL responses in HIV-1 subtype B infections.


Assuntos
Vacinas contra a AIDS/imunologia , HIV-1/imunologia , Peptídeos/imunologia , Linfócitos T Citotóxicos/imunologia , Algoritmos , Sequência de Aminoácidos , Bases de Dados Genéticas , Epitopos/imunologia , Antígenos HIV/imunologia , Humanos , Imunidade Celular/imunologia , Dados de Sequência Molecular
14.
J Acquir Immune Defic Syndr ; 39(4): 499-501, 2005 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-16010176

RESUMO

OBJECTIVE: : To determine predictors of loss to follow-up (LTFU) in trials of candidate HIV vaccines. METHODS: : Data were obtained from trials of candidate preventive HIV vaccines conducted by the AIDS Vaccine Evaluation Group (AVEG) and HIV Network for Prevention Trials (HIVNET) that enrolled HIV-negative volunteers. Analytic models included multiple logistic regression and generalized estimating equations. RESULTS: : Of 3033 volunteers enrolled in 48 trials, 282 (9.3%) persons did not complete follow-up. In univariate analyses, age, trial duration, and number of immunizations were associated with LTFU. In a multivariate logistic model, age (per year) (adjusted odds ratio [AOR] = 0.96, 95% confidence interval [CI]: 0.95, 0.98) and study duration (per month) (AOR = 1.04, 95% CI: 1.01, 1.08) remained significantly associated with LTFU. CONCLUSIONS: : Younger age and increasing trial duration predicted LTFU. Limiting enrollment in trials of novel products to those less than 40 years of age may exclude participants shown to have improved retention. Trials should be designed to last only as long as required to address the scientific question. Retention efforts in future trials should especially address younger persons.


Assuntos
Vacinas contra a AIDS , Ensaios Clínicos Fase I como Assunto/estatística & dados numéricos , Ensaios Clínicos Fase II como Assunto/estatística & dados numéricos , Pacientes Desistentes do Tratamento/estatística & dados numéricos , Adulto , Fatores Etários , Feminino , Humanos , Masculino , Razão de Chances , Estudos Retrospectivos , Fatores de Tempo
15.
J Infect Dis ; 191(3): 358-66, 2005 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-15633094

RESUMO

The impact of demographic characteristics, phase of the menstrual cycle, use of hormonal contraceptives, and concomitant lower genital-tract infections on cervicovaginal inflammatory cells was assessed in 967 women, 654 of whom were infected with human immunodeficiency virus type 1 (HIV-1). Cervicovaginal lavage (CVL) fluid was evaluated for total white blood cell (WBC), polymorphonuclear leukocyte, and monocyte counts. HIV-1 infection was not associated with statistically significant differences in numbers of inflammatory cells in CVL fluid except in 1 group--HIV-1-infected women with Chlamydia trachomatis infection had a 0.43 log(10) higher WBC count than their HIV-uninfected, chlamydia-positive counterparts (P=.04). Younger age and use of progesterone-based hormonal contraceptives were independently associated with increased numbers of inflammatory cells in CVL fluid. A 0.15-0.2 log(10) increase in inflammatory cells was seen in black versus white and Hispanic women after adjustment for known potential confounders. Progesterone-based contraceptives, younger age, and race have an independent effect on cervicovaginal inflammatory cells.


Assuntos
Colo do Útero/imunologia , Hormônios Esteroides Gonadais/farmacologia , Infecções por HIV/epidemiologia , Inflamação/imunologia , Infecções Sexualmente Transmissíveis/epidemiologia , Vagina/imunologia , Adolescente , Adulto , Colo do Útero/efeitos dos fármacos , Feminino , Doenças dos Genitais Femininos/epidemiologia , Doenças dos Genitais Femininos/etiologia , Infecções por HIV/complicações , HIV-1 , Humanos , Ciclo Menstrual , Pessoa de Meia-Idade , Infecções Sexualmente Transmissíveis/complicações , Infecções Sexualmente Transmissíveis/etiologia , Vagina/efeitos dos fármacos
16.
AIDS Rev ; 5(2): 87-103, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12876898

RESUMO

The medical, social, and economic impact of the human immunodeficiency virus (HIV) epidemic has underscored the need to quickly develop effective control strategies. Vigorous efforts to develop a vaccine and therapeutic agents have not yet succeeded in containing the spread of the virus. Studies of persons who remain uninfected despite extensive exposure to HIV continue to provide valuable information on mechanisms of natural protection, which can then be applied to vaccine design. Natural resistance to infection has been studied in multiple high-risk cohorts, with resistance attributed to a combination of innate, genetic, and acquired immune system-mediated mechanisms. The relative contributions of these factors to natural resistance to HIV-1 infection and possible ways in which they can be applied to vaccine design are discussed.


Assuntos
Suscetibilidade a Doenças , Infecções por HIV/imunologia , Infecções por HIV/transmissão , HIV-1/imunologia , Vacinas contra a AIDS/imunologia , Suscetibilidade a Doenças/imunologia , Infecções por HIV/genética , Humanos , Imunidade Inata/imunologia , Fatores de Risco
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