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1.
J Infect Dis ; 229(4): 1131-1140, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38019657

RESUMO

BACKGROUND: Despite highly effective HIV preexposure prophylaxis (PrEP) options, no options provide on-demand, nonsystemic, behaviorally congruent PrEP that many desire. A tenofovir-medicated rectal douche before receptive anal intercourse may provide this option. METHODS: Three tenofovir rectal douches-220 mg iso-osmolar product A, 660 mg iso-osmolar product B, and 660 mg hypo-osmolar product C-were studied in 21 HIV-negative men who have sex with men. We sampled blood and colorectal tissue to assess safety, acceptability, pharmacokinetics, and pharmacodynamics. RESULTS: The douches had high acceptability without toxicity. Median plasma tenofovir peak concentrations for all products were several-fold below trough concentrations associated with oral tenofovir disoproxil fumarate (TDF). Median colon tissue mucosal mononuclear cell (MMC) tenofovir-diphosphate concentrations exceeded target concentrations from 1 hour through 3 to 7 days after dosing. For 6-7 days after a single product C dose, MMC tenofovir-diphosphate exceeded concentrations expected with steady-state oral TDF 300 mg on-demand 2-1-1 dosing. Compared to predrug baseline, HIV replication after ex vivo colon tissue HIV challenge demonstrated a concentration-response relationship with 1.9 log10 maximal effect. CONCLUSIONS: All 3 tenofovir douches achieved tissue tenofovir-diphosphate concentrations and colorectal antiviral effect exceeding oral TDF and with lower systemic tenofovir. Tenofovir douches may provide a single-dose, on-demand, behaviorally congruent PrEP option, and warrant continued development. Clinical Trials Registration . NCT02750540.


Assuntos
Adenina/análogos & derivados , Fármacos Anti-HIV , Neoplasias Colorretais , Infecções por HIV , Organofosfatos , Profilaxia Pré-Exposição , Minorias Sexuais e de Gênero , Masculino , Humanos , Tenofovir , Infecções por HIV/prevenção & controle , Infecções por HIV/tratamento farmacológico , Emtricitabina , Homossexualidade Masculina , Difosfatos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico
2.
Microbiol Spectr ; 10(6): e0446922, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36453916

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection kinetics in a real-world, clinical setting represent a knowledge gap in understanding the underlying coronavirus disease 2019 (COVID-19) pathogenesis. There are scant reports of the dynamics describing the two principal components of the viral life cycle, namely, the rapid proliferation and slower clearance phases. Here, we present results from an ongoing workplace clinical surveillance study during which two vaccinated participants became infected with SARS-CoV-2 Omicron variant (BA.1. lineage). The subjects were followed longitudinally with high temporal resolution, allowing the kinetics of both viral phases to be characterized. The viral doubling times in the proliferation phase (3.3 to 3.5 h) and maximum measured viral loads were similar to those observed for unvaccinated individuals infected with an earlier SARS-CoV-2 strain. However, the clearance phase was much shorter in the current study and unexpectedly displayed a multimodal profile. Longitudinal whole-genome SARS-CoV-2 sequencing identified a stable mutation that arose in one of the participants over the 2-week period of positivity. Our small study provides rare insight into the clinical SARS-CoV-2 dynamics, with significance for public health measures and the biology underlying COVID-19. IMPORTANCE We are conducting an ongoing SARS-CoV-2 workplace clinical study based on frequent, longitudinal disease surveillance of staff and household members. Here, we investigated the viral dynamics in two recently vaccinated participants who became infected with the same Omicron variant of SARS-CoV-2. Because the subjects were enrolled in our study, we were able to track the entire viral life cycle with high temporal resolution, with samples collected every 12 h. Surprisingly, the short viral proliferation phase and maximum viral loads in nasal swab samples were similar to our previous observations with unvaccinated participants and an earlier viral strain. However, the decay phase, indicative of viral clearance, was much shorter here. Our results provide a rare, real-world glimpse of the clinical SARS-CoV-2 replication kinetics, potentially impacting immediate therapies and awareness of earlier and greater transmission potential.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/prevenção & controle , Cinética , Vacinação
3.
Commun Med (Lond) ; 2: 129, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36238348

RESUMO

Background: A comprehensive understanding of the SARS-CoV-2 infection dynamics and the ensuing host immune responses is needed to explain the pathogenesis as it relates to viral transmission. Knowledge gaps exist surrounding SARS-CoV-2 in vivo kinetics, particularly in the earliest stages after exposure. Methods: An ongoing, workplace clinical surveillance study was used to intensely sample a small cohort longitudinally. Nine study participants who developed COVID-19 between November, 2020 and March, 2021 were monitored at high temporal resolution for three months in terms of viral loads as well as associated inflammatory biomarker and antibody responses. CD8 + T cells targeting SARS-CoV-2 in blood samples from study participants were evaluated. Results: Here we show that the resulting datasets, supported by Bayesian modeling, allowed the underlying kinetic processes to be described, yielding a number of unexpected findings. Early viral replication is rapid (median doubling time, 3.1 h), providing a narrow window between exposure and viral shedding, while the clearance phase is slow and heterogeneous. Host immune responses different widely across participants. Conclusions: Results from our small study give a rare insight into the life-cycle of COVID-19 infection and hold a number of important biological, clinical, and public health implications.

4.
Res Sq ; 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36172125

RESUMO

The SARS-CoV-2 infection kinetics in a real-world, clinical setting represent a knowledge gap in understanding the underlying COVID-19 pathogenesis. There are scant reports on the dynamics describing the two principal components of the viral life cycle, namely the rapid proliferation and slower clearance phases. Here, we present results from an ongoing workplace clinical surveillance study where two vaccinated participants became infected with SARS-CoV-2 Omicron variant (BA.1. lineage). The subjects were followed longitudinally at high temporal resolution allowing the kinetics of both viral phases to be characterized. The viral doubling times in the proliferation phase (3.3-3.5 h) and maximum measured viral loads were similar to those observed for unvaccinated individuals infected with an earlier SARS-CoV-2 strain. However, the clearance phase was much shorter in the current study and unexpectedly displayed a multimodal profile. Longitudinal whole genome SARS-CoV-2 sequencing identified a stable mutation that arose in one of the participants over the 2-week period of positivity. Our small study provides a rare insight into the clinical SARS-CoV-2 dynamics holding significance to public health measures and the biology underlying COVID-19.

5.
AIDS Res Hum Retroviruses ; 38(4): 269-278, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34384282

RESUMO

The Combination HIV Antiretroviral Rectal Microbicide-3 (CHARM-03) study was a randomized, open-label, crossover Phase 1 safety and pharmacokinetic (PK) study of oral maraviroc (MVC) and MVC 1% gel. At a single site, healthy HIV-uninfected men and women were enrolled and randomized to an open label crossover sequence of eight consecutive daily exposures to MVC 300 mg dosed orally, MCV 1% gel dosed rectally, and MVC 1% gel dosed vaginally. Male participants received oral and rectal dosing and female participants received oral, rectal, and vaginal dosing. Assessments were undertaken at baseline and following each 8-day period and included collection of plasma, rectal/cervical tissue (CT), and rectal/endocervical/vaginal fluids. Eleven men and nine women were enrolled. Two participants withdrew from the study before receiving study product. There were 25 adverse events, of which 24 were Grade 1 (G1) and one was G2 (unrelated). After eight doses, MVC was quantifiable in all samples following oral, rectal, or vaginal product administration. The highest drug concentrations in plasma, rectal tissue (RT), and CT were associated with oral, rectal, and vaginal drug delivery, respectively. There were significant reductions in tissue drug concentrations when rectal and cervical biopsies were incubated in media before tissue processing for PK (p < .0001). Only oral MVC was associated with limited protection in the rectal explant HIV challenge model (p < .05). There were no immunological changes in RT, and all products were acceptable to participants. In conclusion, all products were found to be safe and acceptable and did not induce local inflammation. The lack of ex vivo efficacy demonstrated in study samples may be due to rapid disassociation of MVC from the explant tissue. ClinicalTrials.gov Identifier: NCT02346084.


Assuntos
Fármacos Anti-HIV , Anti-Infecciosos , Infecções por HIV , Fármacos Anti-HIV/farmacologia , Anti-Infecciosos/uso terapêutico , Antirretrovirais/uso terapêutico , Cicloexanos/efeitos adversos , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Humanos , Masculino , Maraviroc/efeitos adversos
6.
mSphere ; 6(4): e0054221, 2021 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-34232081

RESUMO

Public health practices and high vaccination rates currently represent the primary interventions for managing the spread of coronavirus disease 2019 (COVID-19). We initiated a clinical study based on frequent, longitudinal workplace disease surveillance to control severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission among employees and their household members. We hypothesized that the study would reduce the economic burden and loss of productivity of both individuals and small businesses resulting from standard isolation methods, while providing new insights into virus-host dynamics. Study participants (27 employees and 27 household members) consented to provide frequent nasal or oral swab samples that were analyzed by reverse transcription-quantitative PCR (RT-qPCR) for SARS-CoV-2 RNA. Two study participants were found to be infected by SARS-CoV-2 during the study. One subject, a household member, was SARS-CoV-2 RNA positive for at least 71 days and had quantifiable serum virus-specific antibody concentrations for over 1 year. One unrelated employee became positive for SARS-CoV-2 RNA over the course of the study but remained asymptomatic, with low associated viral RNA copy numbers, no detectable serum IgM and IgG concentrations, and IgA concentrations that decayed rapidly (half-life: 1.3 days). A COVID-19 infection model was used to predict that without surveillance intervention, up to 7 employees (95% confidence interval [CI] = 3 to 10) would have become infected, with at most 1 of them requiring hospitalization. Our scalable and transferable surveillance plan met its primary objectives and represents a powerful example of an innovative public health initiative dovetailed with scientific discovery. IMPORTANCE The rapid spread of SARS-CoV-2 and the associated COVID-19 has precipitated a global pandemic heavily challenging our social behavior, economy, and health care infrastructure. In the absence of widespread, worldwide access to safe and effective vaccines and therapeutics, public health measures represent a key intervention for curbing the devastating impacts from the pandemic. We are conducting an ongoing clinical study based on frequent, longitudinal workplace disease surveillance to control SARS-CoV-2 transmission among employees and their household members. Our study was successful in surveying the viral and immune response dynamics in two participants with unusual infections: one remained positive for SARS-CoV-2 for 71 days, while the other was asymptomatic, with low associated viral RNA copy numbers. A COVID-19 infection model was used to predict that without surveillance intervention, up to 7 employees would have become infected, with at most 1 of them requiring hospitalization, underscoring the importance of our program.


Assuntos
COVID-19/imunologia , SARS-CoV-2/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/virologia , Criança , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Pandemias/prevenção & controle , Saúde Pública , RNA Viral/imunologia , Local de Trabalho , Adulto Jovem
7.
AIDS ; 35(10): 1585-1595, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33831911

RESUMO

OBJECTIVE: The objective of this study was to compare HIV-negative cisgender women (CGW) with MSM for mucosal tissue differences in pharmacokinetics, HIV infectivity and cell phenotype. DESIGN: A substudy of HPTN 069/ACTG A5305, 48-week study of three oral candidate preexposure prophylaxis regimens: maraviroc, maraviroc/emtricitabine and maraviroc/tenofovir disoproxil fumarate (TDF) compared with a TDF/emtricitabine control group. METHODS: Plasma, peripheral blood mononuclear cells and cervical and colorectal tissue biopsies were collected at Baseline (no drug), Week 24 and 48 (on drug), and Week 49 (1-week postdrug). Drug concentrations were assessed in all matrices. HIV infectivity was assessed using tissue biopsy 'explants' challenged with HIV ex vivo followed by HIV p24 measurement. Flow cytometry evaluated colorectal cell phenotype. RESULTS: Thirty-seven CGW and 54 MSM participated. CGW's colorectal explant p24 was higher than MSM before (0.31 log10, P = 0.046), during (1.01-1.19 log10, P = 0.016) and one week after (0.61 log10, P = 0.011) study drug dosing. Pooling regimens, cervical explant p24 did not differ among visits. CGW had higher plasma maraviroc and colorectal tissue tenofovir diphosphate and lower colorectal tissue emtricitabine (all P < 0.005) compared with MSM. Each study drug's cervical tissue concentrations were more than 10-fold below paired colorectal concentrations (P < 0.001). Cell phenotype sex differences included 4% higher CD38+/CD8+ cells at baseline and 3-7% higher CD69+/CD8+ cells throughout Weeks 24-49 in CGW compared with MSM (P < 0.05). CONCLUSION: Colorectal explants in CGW demonstrated greater HIV infectivity than MSM with and without study drugs. Small differences in adherence, drug concentration and colorectal tissue flow cytometry cannot fully explain this difference.


Assuntos
Fármacos Anti-HIV , Neoplasias Colorretais , Infecções por HIV , Profilaxia Pré-Exposição , Minorias Sexuais e de Gênero , Emtricitabina , Feminino , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Humanos , Leucócitos Mononucleares , Masculino
8.
CPT Pharmacometrics Syst Pharmacol ; 10(3): 179-187, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33547874

RESUMO

Defining tissue and plasma-specific prophylactic drug concentrations is central to pre-exposure prophylaxis product development for sexual transmission of HIV-1. Pharmacokinetic (PK) data from study RMP-02/MTN-006 comparing single dose oral tenofovir disoproxil fumarate with single and multiple dose rectal tenofovir (TFV) gel administration in HIV-1 seronegative adults was used to construct a multicompartment plasma-rectal tissue population PK model for TFV and tenofovir-diphosphate (TFVdp) in plasma and rectal tissue. PK data were collected in five matrices: TFV (plasma, rectal tissue homogenate), TFVdp (peripheral blood mononuclear cells, rectal mononuclear cells (MMCs), rectal tissue homogenate). A viral growth compartment and a delayed effect compartment for p24 antigen expression measured from an ex vivo explant assay described HIV-1 infection and replication. Using a linear PK/pharmacodynamic model, MMC TFVdp levels over 9,000 fmol/million cells in the explant assay provided apparent viral replication suppression down to 1%. Parameters were estimated using NONMEM version 7.4.


Assuntos
Fármacos Anti-HIV/farmacocinética , Infecções por HIV/prevenção & controle , Leucócitos Mononucleares/efeitos dos fármacos , Tenofovir/farmacocinética , Replicação Viral/efeitos dos fármacos , Administração Oral , Administração Retal , Adulto , Idoso , Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/farmacologia , Disponibilidade Biológica , Desenvolvimento de Medicamentos/métodos , Feminino , Géis/farmacologia , Géis/uso terapêutico , Proteína do Núcleo p24 do HIV/efeitos dos fármacos , Proteína do Núcleo p24 do HIV/metabolismo , Soronegatividade para HIV/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Profilaxia Pré-Exposição/métodos , Reto/citologia , Reto/efeitos dos fármacos , Tenofovir/administração & dosagem , Tenofovir/farmacologia
9.
Biotechnol Bioeng ; 118(4): 1707-1720, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33484156

RESUMO

Expression of viral capsomeres in bacterial systems and subsequent in vitro assembly into virus-like particles is a possible pathway for affordable future vaccines. However, purification is challenging as viral capsomeres show poor binding to chromatography media. In this study, the behavior of capsomeres in unfractionated bacterial lysate was compared with that for purified capsomeres, with or without added microbial DNA, to better understand reasons for poor bioprocess behavior. We show that aggregates or complexes form through the interaction between viral capsomeres and DNA, especially in bacterial lysates rich in contaminating DNA. The formation of these complexes prevents the target protein capsomeres from accessing the pores of chromatography media. We find that protein-DNA interactions can be modulated by controlling the ionic strength of the buffer and that at elevated ionic strengths the protein-DNA complexes dissociate. Capsomeres thus released show enhanced bind-elute behavior on salt-tolerant chromatography media. DNA could therefore be efficiently removed. We believe this is the first report of the use of an optimized salt concentration that dissociates capsomere-DNA complexes yet enables binding to salt-tolerant media. Post purification, assembly experiments indicate that DNA-protein interactions can play a negative role during in vitro assembly, as DNA-protein complexes could not be assembled into virus-like particles, but formed worm-like structures. This study reveals that the control over DNA-protein interaction is a critical consideration during downstream process development for viral vaccines.


Assuntos
Proteínas do Capsídeo , DNA Bacteriano/química , Escherichia coli , Vacinas de Partículas Semelhantes a Vírus , Proteínas do Capsídeo/biossíntese , Proteínas do Capsídeo/química , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/isolamento & purificação , Cromatografia Líquida , Escherichia coli/química , Escherichia coli/genética , Escherichia coli/metabolismo , Vacinas de Partículas Semelhantes a Vírus/biossíntese , Vacinas de Partículas Semelhantes a Vírus/química , Vacinas de Partículas Semelhantes a Vírus/genética , Vacinas de Partículas Semelhantes a Vírus/isolamento & purificação
10.
Am J Reprod Immunol ; 84(2): e13263, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32384198

RESUMO

PROBLEM: Receptive anal intercourse (RAI) is more efficient than receptive vaginal intercourse (RVI) at transmitting HIV, but its contribution to heterosexually acquired HIV infections among at-risk women in the USA is unclear. METHOD OF STUDY: We analysed sexual behaviour data from surveys of 9152 low-income heterosexual women living in 20 cities with high rates of HIV conducted in 2010 and 2013 as part of US National HIV Behavioral Surveillance. We estimated RAI prevalence (past-year RAI) and RAI fraction (fraction of all sex acts (RVI and RAI) at the last sexual episode that were RAI among those reporting past-year RAI) overall and by key demographic characteristics. These results and HIV incidence were used to calibrate a risk equation model to estimate the population attributable fraction of new HIV infections due to RAI (PAFRAI ) accounting for uncertainty in parameter assumptions. RESULTS: Receptive anal intercourse prevalence (overall: 32%, city range: 19%-60%) and RAI fraction (overall: 27%, city range: 18%-34%) were high overall and across cities, and positively associated with exchange sex. RAI accounted for an estimated 41% (uncertainty range: 18%-55%) of new infections overall (city range: 21%-57%). Variability in PAFRAI estimates was most influenced by uncertainty in the estimate of the per-act increased risk of RAI relative to RVI and the number of sex acts. CONCLUSION: Receptive anal intercourse may contribute disproportionately to new heterosexually acquired HIV infections among at-risk low-income women in the USA, meaning that tools to prevent HIV transmission during RAI are warranted. The number of RVI and RAI acts should also be collected to monitor heterosexually acquired HIV infections.


Assuntos
Infecções por HIV/epidemiologia , HIV/fisiologia , Heterossexualidade/estatística & dados numéricos , Sêmen/virologia , Comportamento Sexual/estatística & dados numéricos , Adulto , Feminino , Humanos , Modelos Estatísticos , Pobreza , Prevalência , Risco , Sêmen/imunologia , Estados Unidos/epidemiologia , Sexo sem Proteção , População Urbana
11.
AIDS Behav ; 24(3): 697-713, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30953304

RESUMO

HIV is more efficiently acquired during receptive anal intercourse (AI) compared to vaginal intercourse (VI) and may contribute substantially to female sex workers' (FSW) high HIV burden. We aim to determine how common and frequent AI is among FSW globally. We searched PubMed, Embase and PsycINFO for studies reporting the proportion of FSW practising AI (prevalence) and/or the number of AI acts (frequency) worldwide from 01/1980 to 10/2018. We assessed the influence of participant and study characteristics on AI prevalence (e.g. continent, study year and interview method) through sub-group analysis. Of 15,830 identified studies, 131 were included. Nearly all (N = 128) reported AI prevalence and few frequency (N = 13), over various recall periods. Most studies used face-to-face interviews (N = 111). Pooled prevalences varied little by recall period (lifetime: 15.7% 95%CI 12.2-19.3%, N = 30, I2 = 99%; past month: 16.2% 95%CI 10.8-21.6%, N = 18, I2 = 99%). The pooled proportion of FSW reporting < 100% condom use tended to be non-significantly higher during AI compared to during VI (e.g. any unprotected VI: 19.1% 95%CI 1.7-36.4, N = 5 and any unprotected AI: 46.4% 95%CI 9.1-83.6, N = 5 in the past week). Across all study participants, between 2.4 and 15.9% (N = 6) of all intercourse acts (AI and VI) were anal. Neither AI prevalence nor frequency varied substantially by any participant or study characteristics. Although varied, AI among FSW is generally common, inconsistently protected with condoms and practiced sufficiently frequently to contribute substantially to HIV acquisition in this risk group. Interventions to address barriers to condom use are needed.


Assuntos
Canal Anal , Preservativos/estatística & dados numéricos , Infecções por HIV/transmissão , Profissionais do Sexo/estatística & dados numéricos , Comportamento Sexual/estatística & dados numéricos , Coito , Feminino , Infecções por HIV/epidemiologia , Humanos , Prevalência , Fatores de Risco , Sexo Seguro , Vagina
12.
AIDS Behav ; 24(3): 667-681, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31486008

RESUMO

Receptive anal intercourse (RAI) carries a greater per-act risk of HIV acquisition than receptive vaginal intercourse (RVI) and may influence HIV epidemics driven by heterosexual sex. This systematic review explores the association between RAI and incident HIV among women, globally. We searched Embase and Medline through September 2018 for longitudinal studies reporting crude (cRR) or adjusted (aRR) relative risks of HIV acquisition by RAI practice among women. Of 27,563 articles identified, 17 eligible studies were included. We pooled independent study estimates using random-effects models. Women reporting RAI were more likely to acquire HIV than women not reporting RAI (pooled cRR = 1.56 95% CI 1.03-2.38, N = 18, I2 = 72%; pooled aRR = 2.23, 1.01-4.92, N = 5, I2 = 70%). In subgroup analyses the association was lower for women in Africa (pooled cRR = 1.16, N = 13, I2 = 21%) than outside Africa (pooled cRR = 4.10, N = 5, I2 = 79%) and for high-risk (pooled aRR = 1.69, N = 4, I2 = 63%) than general-risk women (pooled aRR = 8.50, N = 1). Interview method slightly influenced cRR estimates (p value = 0.04). In leave-one-out sensitivity analyses pooled estimates were generally robust to removing individual study estimates. Main limitations included poor exposure definition, incomplete adjustment for confounders, particularly condom use, and use of non-confidential interview methods. More and better data are needed to explain differences in risk by world region and risk population. Women require better counselling and greater choice in prevention modalities that are effective during RVI and RAI.


Assuntos
Canal Anal/virologia , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Heterossexualidade/estatística & dados numéricos , Sexo Seguro/estatística & dados numéricos , Comportamento Sexual/estatística & dados numéricos , Adulto , Epidemias , Feminino , Infecções por HIV/diagnóstico , Humanos , Incidência , Masculino , Fatores de Risco , Comportamento Sexual/psicologia
13.
Bioconjug Chem ; 30(8): 2216-2227, 2019 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-31265254

RESUMO

"Vaults" are ubiquitously expressed endogenous ribonucleoprotein nanoparticles with potential utility for targeted drug delivery. Here, we show that recombinant human vault nanoparticles are readily engulfed by certain key human peripheral blood mononuclear cells (PBMC), predominately dendritic cells, monocytes/macrophages, and activated T cells. As these cell types are the primary targets for human immunodeficiency virus type 1 (HIV-1) infection, we examined the utility of recombinant human vaults for targeted delivery of antiretroviral drugs. We chemically modified three different antiretroviral drugs, zidovudine, tenofovir, and elvitegravir, for direct conjugation to vaults. Tested in infection assays, drug-conjugated vaults inhibited HIV-1 infection of PBMC with equivalent activity to free drugs, indicating vault delivery and drug release in the cytoplasm of HIV-1-susceptible cells. The ability to deliver functional drugs via vault nanoparticle conjugates suggests their potential utility for targeted drug delivery against HIV-1.


Assuntos
Antirretrovirais/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Infecções por HIV/tratamento farmacológico , Nanopartículas/uso terapêutico , Antirretrovirais/química , Células Cultivadas , Citoplasma/metabolismo , Liberação Controlada de Fármacos , Infecções por HIV/prevenção & controle , HIV-1 , Humanos , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/virologia , Nanopartículas/química , Nanopartículas/metabolismo , Ribonucleoproteínas
14.
AIDS ; 33(2): 237-246, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30557160

RESUMO

OBJECTIVE: HIV Prevention Trials Network 069/AIDS Clinical Trials Group A5305 was a study of 48-week oral pre-exposure prophylaxis (PrEP) regimens in MSM and transgender women. A rectal substudy was included to evaluate drug concentrations in rectal compartment vs. blood, gut-associated lymphoid tissue (GALT) responses to four antiretroviral PrEP regimens [maraviroc (MVC), MVC + emtricitabine (FTC), MVC + tenofovir (TFV) disoproxil fumarate, and TFV disoproxil fumarate + FTC], and to determine whether ARV exposure was associated with ex-vivo suppression of HIV infection in colorectal explants. METHODS: C-C chemokine receptor type 5 (CCR5) genotype was characterized using PCR. At baseline and at Weeks 24, 48, and 49, GALT phenotype was characterized by flow cytometry, rectal biopsies were challenged with HIV-1BaL, and tissue and plasma pharmacokinetics were measured via mass spectrometry. RESULTS: Exposure to MVC was not associated with increased expression of CD4+/CCR5+ HIV target T cells. Significant ex-vivo viral suppression compared with baseline was seen at Weeks 24 and 48, ranging from 1.4 to 1.8 log10 for all study regimens except the MVC-alone arm which did not show statistically significant viral suppression at Week 48. Tissue concentrations of TFV, TFV-diphosphate, and FTC were correlated with viral suppression. CONCLUSION: MVC-containing HIV PrEP regimens did not increase GALT CD4+ T-cell activation or the CD4+/CCR5+ phenotype. No virologic suppression was seen with MVC-alone at Week 48 compared with combination regimens, suggesting MVC monotherapy might be less effective than combination antiretroviral PrEP regimens.


Assuntos
Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/farmacocinética , Análise Química do Sangue , Maraviroc/farmacologia , Maraviroc/farmacocinética , Profilaxia Pré-Exposição/métodos , Reto/química , Adolescente , Adulto , Idoso , Fármacos Anti-HIV/administração & dosagem , Método Duplo-Cego , Quimioterapia Combinada/métodos , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Humanos , Mucosa Intestinal/química , Tecido Linfoide/química , Masculino , Maraviroc/administração & dosagem , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
15.
Am J Reprod Immunol ; 80(5): e13039, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30175479

RESUMO

Quantifying HIV-1 transmission risk per-act of anal intercourse (AI) is important for HIV-1 prevention. We updated previous reviews by searching Medline and Embase to 02/2018. We derived pooled estimates of receptive AI (URAI) and insertive AI (UIAI) risk unprotected by condoms using random-effects models. Subgroup analyses were conducted by gender, study design, and whether antiretroviral treatment (ART) had been introduced by the time of the study. Two new relevant studies were identified, one of which met inclusion criteria, adding three new cohorts and increasing number of individuals/partnerships included from 1869 to 14 277. Four studies, all from high-income countries, were included. Pooled HIV-1 risk was higher for URAI (1.25%, 95% CI 0.55%-2.23%, N = 5, I2  = 87%) than UIAI (0.17%, 95 % CI 0.09%-0.26%, N = 3, I2  = 0%). The sole heterosexual URAI estimate (3.38%, 95% CI 1.85%-4.91%), from a study of 72 women published in a peer-reviewed journal, was significantly higher than the men-who-have-sex-with-men (MSM) pooled estimate (0.75%, 95% CI 0.56%-0.98%, N = 4, P < 0.0001) and higher than the only other heterosexual estimate identified (0.4%, 95% CI 0.08%-2.0%, based on 59 women, excluded for being a pre-2013 abstract). Pooled per-act URAI risk varied by study design (retrospective-partner studies: 2.56%, 95% CI 1.20%-4.42%, N = 2 (one MSM, one heterosexual); prospective studies: 0.71%, 95% CI 0.51%-0.93%, N = 3 MSM, P < 0.0001). URAI risk was lower for studies conducted in the ART era (0.75%, 95% CI 0.52%-1.03%) than pre-ART (1.67%, 95% CI 0.44%-3.67%) but not significantly so (P = 0.537). Prevention messages must emphasize that HIV-1 infectiousness through AI remains high, even in the ART era. Further studies, particularly among heterosexual populations and in resource-limited settings, are required to elucidate whether AI risk differs by gender, region and following population-level ART scale-up.


Assuntos
Infecções por HIV/epidemiologia , HIV-1/fisiologia , Fatores Sexuais , Comportamento Sexual/estatística & dados numéricos , Feminino , Heterossexualidade , Humanos , Masculino , Risco , Minorias Sexuais e de Gênero
16.
PLoS Med ; 15(9): e1002655, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30265679

RESUMO

BACKGROUND: Intravaginal rings (IVRs) for HIV pre-exposure prophylaxis (PrEP) theoretically overcome some adherence concerns associated with frequent dosing that can occur with oral or vaginal film/gel regimens. An innovative pod-IVR, composed of an elastomer scaffold that can hold up to 10 polymer-coated drug cores (or "pods"), is distinct from other IVR designs as drug release from each pod can be controlled independently. A pod-IVR has been developed for the delivery of tenofovir (TFV) disoproxil fumarate (TDF) in combination with emtricitabine (FTC), as daily oral TDF-FTC is the only Food and Drug Administration (FDA)-approved regimen for HIV PrEP. A triple combination IVR building on this platform and delivering TDF-FTC along with the antiretroviral (ARV) agent maraviroc (MVC) also is under development. METHODOLOGY AND FINDINGS: This pilot Phase I trial conducted between June 23, 2015, and July 15, 2016, evaluated the safety, pharmacokinetics (PKs), and acceptability of pod-IVRs delivering 3 different ARV regimens: 1) TDF only, 2) TDF-FTC, and 3) TDF-FTC-MVC over 7 d. The crossover, open-label portion of the trial (N = 6) consisted of 7 d of continuous TDF pod-IVR use, a wash-out phase, and 7 d of continuous TDF-FTC pod-IVR use. After a 3-mo pause to evaluate safety and PK of the TDF and TDF-FTC pod-IVRs, TDF-FTC-MVC pod-IVRs (N = 6) were evaluated over 7 d of continuous use. Safety was assessed by adverse events (AEs), colposcopy, and culture-independent analysis of the vaginal microbiome (VMB). Drug and drug metabolite concentrations in plasma, cervicovaginal fluids (CVFs), cervicovaginal lavages (CVLs), and vaginal tissue (VT) biopsies were determined via liquid chromatographic-tandem mass spectrometry (LC-MS/MS). Perceptibility and acceptability were assessed by surveys and interviews. Median participant age was as follows: TDF/TDF-FTC group, 26 y (range 24-35 y), 2 White, 2 Hispanic, and 2 African American; TDF-FTC-MVC group, 24.5 y (range 21-41 y), 3 White, 1 Hispanic, and 2 African American. Reported acceptability was high for all 3 products, and pod-IVR use was confirmed by residual drug levels in used IVRs. There were no serious adverse events (SAEs) during the study. There were 26 AEs reported during TDF/TDF-FTC IVR use (itching, discharge, discomfort), with no differences between TDF alone or in combination with FTC observed. In the TDF-FTC-MVC IVR group, there were 12 AEs (itching, discharge, discomfort) during IVR use regardless of attribution to study product. No epithelial disruption/thinning was seen by colposcopy, and no systematic VMB shifts were observed. Median (IQR) tenofovir diphosphate (TFV-DP) tissue concentrations of 303 (277-938) fmol/10(6) cells (TDF), 289 (110-603) fmol/10(6) cells (TDF-FTC), and 302 (177.1-823.8) fmol/10(6) cells (TDF-FTC-MVC) were sustained for 7 d, exceeding theoretical target concentrations for vaginal HIV prevention. The study's main limitations include the small sample size, short duration (7 d versus 28 d), and the lack of FTC triphosphate measurements in VT biopsies. CONCLUSIONS: An innovative pod-IVR delivery device with 3 different formulations delivering different regimens of ARV drugs vaginally appeared to be safe and acceptable and provided drug concentrations in CVFs and tissues exceeding concentrations achieved by highly protective oral dosing, suggesting that efficacy for vaginal HIV PrEP is achievable. These results show that an alternate, more adherence-independent, longer-acting prevention device based on the only FDA-approved PrEP combination regimen can be advanced to safety and efficacy testing. TRIAL REGISTRATION: ClinicalTrials.gov NCT02431273.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Infecções por HIV/prevenção & controle , HIV-1 , Profilaxia Pré-Exposição/métodos , Administração Intravaginal , Adulto , Fármacos Anti-HIV/efeitos adversos , Fármacos Anti-HIV/farmacocinética , Dispositivos Anticoncepcionais Femininos , Estudos Cross-Over , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Emtricitabina/administração & dosagem , Emtricitabina/efeitos adversos , Emtricitabina/farmacocinética , Feminino , Humanos , Maraviroc/administração & dosagem , Maraviroc/efeitos adversos , Maraviroc/farmacocinética , Satisfação do Paciente , Tenofovir/administração & dosagem , Tenofovir/efeitos adversos , Tenofovir/farmacocinética , Adulto Jovem
17.
PLoS One ; 13(8): e0201952, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30133534

RESUMO

BACKGROUND: Intravaginal rings (IVRs) can deliver antiretroviral (ARV) agents for HIV pre-exposure prophylaxis (PrEP), theoretically overcoming adherence concerns associated with frequent dosing. However, topical vaginal ARV drug delivery has not simultaneously led to sufficient rectal drug exposure to likely protect from HIV infection as a result of receptive anal intercourse (RAI). Unprotected RAI has a higher risk of infection per sex act and, for women, also can be associated with vaginal exposure during a single sexual encounter, especially in higher-risk subsets of women. The physiologically inflamed, activated, immune-cell dense colorectal mucosa is increasingly appreciated as the sexual compartment with highly significant risk; this risk is increased in the setting of co-infections. Ex vivo studies have shown that colorectal tissue and rectal fluid concentrations correlated with HIV protection. Given these important results, efforts to document colorectal compartment ARV drug concentration from pod-IVR delivery was assessed to determine if vaginal application could provide protective ARV levels in both compartments. METHODOLOGY/PRINCIPAL FINDINGS: A crossover clinical trial (N = 6) evaluated 7 d of continuous TDF pod-IVR use, a wash-out phase, followed by 7 d with a TDF-FTC pod-IVR. A subsequent clinical trial (N = 6) consisted of 7 d of continuous TDF-FTC-MVC pod-IVR use. Rectal fluids were collected on Day 7 at IVR removal in all three ARV-exposures (two Phase 1 trials) and drug concentrations quantified by LC-MS/MS. Median rectal fluid concentrations of TFV, the hydrolysis product of the prodrug TDF, were between 0.66 ng mg-1 (TDF pod-IVR group) and 1.11 ng mg-1 (TDF-FTC pod-IVR group), but below the analytical lower limit of quantitation in 5/6 samples in the TDF-FTC-MVC pod-IVR group. Unexpectedly, median FTC (TDF-FTC pod-IVR, 20.3 ng mg-1; TDF-FTC-MVC pod-IVR, 0.18 ng mg-1), and MVC rectal fluid concentrations (0.84 ng mg-1) were quantifiable and higher than their respective in vitro EC50 values in most samples. Due to participant burden in these exploratory trials, rectal fluid was used as a surrogate for rectal tissue, where drug concentrations are expected to be higher. CONCLUSIONS/SIGNIFICANCE: The concentrations of FTC and MVC in rectal fluids obtained in two exploratory clinical trials of IVRs delivering ARV combinations exceeded levels associated with in vitro efficacy in HIV inhibition. Unexpectedly, MVC appeared to depress the distribution of TFV and FTC into the rectal lumen. Here we show that vaginal delivery of ARV combinations may provide adherence and coitally independent dual-compartment protection from HIV infection during both vaginal and receptive anal intercourse.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , HIV-1/efeitos dos fármacos , Vagina/virologia , Administração Intravaginal , Relação Dose-Resposta a Droga , Feminino , Humanos , Profilaxia Pré-Exposição
18.
J Infect Dis ; 218(9): 1447-1452, 2018 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-29878133

RESUMO

A 48-year-old woman was infected with a vpr-defective human immunodeficiency virus (HIV)-1 molecular clone. Seroconversion was markedly delayed, and without treatment she had durably suppressed viremia and normal T-cell levels. Neutralizing antibody and CD8+ T-cell immune responses against HIV-1 were unremarkable. Viral sequences confirmed the source but evolved defective nef, suggesting an unknown mechanistic link to vpr. There were subtle qualitative defects in T and B cells. To our knowledge, this is the only case of human infection with a characterized defective HIV-1 molecular clone, which furthermore recapitulated live-attenuated vaccination in macaque models of HIV-1 vaccine research.


Assuntos
Vacinas contra a AIDS/imunologia , Produtos do Gene vpr/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Vacinas Atenuadas/imunologia , Linfócitos B/imunologia , Linfócitos T CD8-Positivos/imunologia , Clonagem Molecular , Feminino , Humanos , Pessoa de Meia-Idade , Vacinação/métodos
19.
AIDS Res Hum Retroviruses ; 34(10): 900-906, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29631414

RESUMO

Ex vivo mucosal explants have become a mainstay of HIV-1 studies using human tissue. In this study, we examine the baseline phenotypic and virologic differences between biopsies derived from the small intestine (SI) and large intestine (LI) for use in ex vivo explant studies. To do this, we collected endoscopic mucosal biopsies from both SI and LI from the same healthy, HIV-seronegative participants. Mucosal mononuclear cell phenotypes and quantity were compared using flow cytometry. Comparative HIV-1 infectibility of the explants was assessed using an ex vivo explant HIV-1 infection assay. We found that all biopsies had similar numbers of T cells per biopsy. While the percentage of CD4+ T cells from SI biopsies expressed significantly more activation markers (CD38, HLA-DR) and HIV coreceptors (CXCR4, CCR5), the absolute numbers of activated CD4+ T cells were similar between both sites. LI explants, however, supported more efficient HIV-1 infection, as evidenced by earlier rise in p24 accumulation and greater percent of infected explants at limiting infectious doses. These results suggest that explants from LI biopsies support more efficient HIV-1 infection than SI biopsies, despite similar numbers of available, activated HIV-1 target cells. These findings highlight important differences in LI and SI explants, which must be considered in designing and interpreting ex vivo HIV-1 infection studies, and suggest that factors within the tissue other than target cell number and activation state may play a role in regulating HIV-1 infection.


Assuntos
Infecções por HIV/patologia , HIV-1/patogenicidade , Intestino Grosso/virologia , Intestino Delgado/virologia , Biópsia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Proteína do Núcleo p24 do HIV/metabolismo , Infecções por HIV/virologia , Voluntários Saudáveis , Humanos , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Mucosa Intestinal/virologia , Intestino Grosso/imunologia , Intestino Grosso/patologia , Intestino Delgado/imunologia , Intestino Delgado/patologia , Ativação Linfocitária , Modelos Biológicos , Fenótipo , Cultura Primária de Células , Receptores de HIV/metabolismo
20.
J Acquir Immune Defic Syndr ; 78(1): 119-123, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29419567

RESUMO

BACKGROUND: Methamphetamine use increases the risk of HIV-1 infection among seronegative users and can exacerbate disease progression in HIV-positive users. The biological mechanisms underlying these associations remain unclear. In this cross-sectional pilot study, we examine the associations between recent methamphetamine use and inflammation in the rectal mucosa and peripheral blood compartments in HIV-1 seropositive and seronegative men who have sex with men. METHODS: HIV-seronegative and HIV-seropositive men who have sex with men participants were enrolled (N = 24). Recent methamphetamine use was determined by urine drug screen. Cytokines were quantified using multiplex arrays from collected plasma and rectal sponge samples, and peripheral blood T-cell activation was assessed by flow cytometry. RESULTS: Methamphetamine use was associated with consistently increased rectal inflammatory cytokines, specifically interleukin-6 and tumor necrosis factor-alpha, regardless of HIV-1 serostatus in this pilot study. This association was significant after adjusting for age, HIV-serostatus, and receptive anal intercourse frequency using regression analysis. Similar increases were not uniformly observed in peripheral blood. CONCLUSIONS: Methamphetamine use is associated with increased local mucosal inflammatory cytokine production. These findings may help explain the increased HIV-1 risk seen in methamphetamine users and contribute to increased inflammation among HIV-seropositive users.


Assuntos
Citocinas/sangue , Infecções por HIV , Soropositividade para HIV , Metanfetamina/efeitos adversos , Mucosa/efeitos dos fármacos , Mucosa/imunologia , Adulto , Estudos Transversais , Trato Gastrointestinal/imunologia , Infecções por HIV/complicações , HIV-1 , Homossexualidade Masculina , Humanos , Inflamação , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Comportamento Sexual , Linfócitos T , Fator de Necrose Tumoral alfa/sangue
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