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2.
PLoS Pathog ; 12(4): e1005580, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27093273

RESUMO

People with HIV infection are at increased risk for community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) skin and soft tissue infections (SSTIs). Lower CD4 T-cell counts, higher peak HIV RNA levels and epidemiological factors may be associated with increased risk but no specific immune defect has been identified. We aimed to determine the immunologic perturbations that predispose HIV-infected people to MRSA SSTIs. Participants with or without HIV infection and with MRSA SSTI, MRSA colonization or negative for MRSA were enrolled. Peripheral blood and skin biopsies from study participants were collected. Flow cytometry, flow cytometry with microscopy, multiplex assays of cell culture supernatants and immunohistochemistry were used to evaluate the nature of the immune defect predisposing HIV-infected people to MRSA infections. We found deficient MRSA-specific IFNγ+ CD4 T-cell responses in HIV-infected people with MRSA SSTIs compared to MRSA-colonized participants and HIV-uninfected participants with MRSA SSTIs. These IFNγ+ CD4 T cells were less polyfunctional in HIV-infected participants with SSTIs compared to those without SSTIs. However, IFNγ responses to cytomegalovirus and Mycobacterium avium antigens and MRSA-specific IL-17 responses by CD4 T cells were intact. Upon stimulation with MRSA, peripheral blood mononuclear cells from HIV-infected participants produced less IL-12 and IL-15, key drivers of IFNγ production. There were no defects in CD8 T-cell responses, monocyte responses, opsonization, or phagocytosis of Staphylococcus aureus. Accumulation of CD3 T cells, CD4 T cells, IL-17+ cells, myeloperoxidase+ neutrophils and macrophage/myeloid cells to the skin lesions were similar between HIV-infected and HIV-uninfected participants based on immunohistochemistry. Together, these results indicate that MRSA-specific IFNγ+ CD4 T-cell responses are essential for the control of initial and recurrent MRSA infections in HIV-infected people.


Assuntos
Coinfecção/imunologia , Infecções por HIV/imunologia , Hospedeiro Imunocomprometido/imunologia , Infecções Estafilocócicas/imunologia , Células Th1/imunologia , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Staphylococcus aureus Resistente à Meticilina , Estudos Prospectivos
3.
PLoS Pathog ; 12(1): e1005381, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26795282

RESUMO

Whether initiation of antiretroviral therapy (ART) regimens aimed at achieving greater concentrations within gut associated lymphoid tissue (GALT) impacts the level of mucosal immune reconstitution, inflammatory markers and the viral reservoir remains unknown. We included 12 HIV- controls and 32 ART-naïve HIV patients who were randomized to efavirenz, maraviroc or maraviroc+raltegravir, each with fixed-dose tenofovir disoproxil fumarate/emtricitabine. Rectal and duodenal biopsies were obtained at baseline and at 9 months of ART. We performed a comprehensive assay of T-cell subsets by flow cytometry, T-cell density in intestinal biopsies, plasma and tissue concentrations of antiretroviral drugs by high-performance liquid chromatography/mass spectroscopy, and plasma interleukin-6 (IL-6), lipoteichoic acid (LTA), soluble CD14 (sCD14) and zonulin-1 each measured by ELISA. Total cell-associated HIV DNA was measured in PBMC and rectal and duodenal mononuclear cells. Twenty-six HIV-infected patients completed the follow-up. In the duodenum, the quadruple regimen resulted in greater CD8+ T-cell density decline, greater normalization of mucosal CCR5+CD4+ T-cells and increase of the naïve/memory CD8+ T-cell ratio, and a greater decline of sCD14 levels and duodenal HIV DNA levels (P = 0.004 and P = 0.067, respectively), with no changes in HIV RNA in plasma or tissue. Maraviroc showed the highest drug distribution to the gut tissue, and duodenal concentrations correlated well with other T-cell markers in duodenum, i.e., the CD4/CD8 ratio, %CD4+ and %CD8+ HLA-DR+CD38+ T-cells. Maraviroc use elicited greater activation of the mucosal naïve CD8+ T-cell subset, ameliorated the distribution of the CD8+ T-cell maturational subsets and induced higher improvement of zonulin-1 levels. These data suggest that combined CCR5 and integrase inhibitor based combination therapy in ART treatment naïve patients might more effectively reconstitute duodenal immunity, decrease inflammatory markers and impact on HIV persistence by cell-dependent mechanisms, and show unique effects of MVC in duodenal immunity driven by higher drug tissue penetration and possibly by class-dependent effects.


Assuntos
Antagonistas dos Receptores CCR5/administração & dosagem , Infecções por HIV/imunologia , Inibidores de Integrase de HIV/administração & dosagem , Imunidade nas Mucosas/efeitos dos fármacos , Subpopulações de Linfócitos T/efeitos dos fármacos , Adulto , Alcinos , Fármacos Anti-HIV/administração & dosagem , Benzoxazinas/administração & dosagem , Cromatografia Líquida de Alta Pressão , Cicloexanos/administração & dosagem , Ciclopropanos , Combinação de Medicamentos , Combinação Emtricitabina e Fumarato de Tenofovir Desoproxila/administração & dosagem , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Infecções por HIV/tratamento farmacológico , Humanos , Ativação Linfocitária/efeitos dos fármacos , Masculino , Maraviroc , Projetos Piloto , Raltegravir Potássico/administração & dosagem , Subpopulações de Linfócitos T/imunologia , Triazóis/administração & dosagem
4.
J Virol ; 89(20): 10156-75, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26223646

RESUMO

UNLABELLED: Deletion of Gly-720 and Tyr-721 from a highly conserved GYxxØ trafficking signal in the SIVmac239 envelope glycoprotein cytoplasmic domain, producing a virus termed ΔGY, leads to a striking perturbation in pathogenesis in rhesus macaques (Macaca mulatta). Infected macaques develop immune activation and progress to AIDS, but with only limited and transient infection of intestinal CD4(+) T cells and an absence of microbial translocation. Here we evaluated ΔGY in pig-tailed macaques (Macaca nemestrina), a species in which SIVmac239 infection typically leads to increased immune activation and more rapid progression to AIDS than in rhesus macaques. In pig-tailed macaques, ΔGY also replicated acutely to high peak plasma RNA levels identical to those for SIVmac239 and caused only transient infection of CD4(+) T cells in the gut lamina propria and no microbial translocation. However, in marked contrast to rhesus macaques, 19 of 21 pig-tailed macaques controlled ΔGY replication with plasma viral loads of <15 to 50 RNA copies/ml. CD4(+) T cells were preserved in blood and gut for up to 100 weeks with no immune activation or disease progression. Robust antiviral CD4(+) T cell responses were seen, particularly in the gut. Anti-CD8 antibody depletion demonstrated CD8(+) cellular control of viral replication. Two pig-tailed macaques progressed to disease with persisting viremia and possible compensatory mutations in the cytoplasmic tail. These studies demonstrate a marked perturbation in pathogenesis caused by ΔGY's ablation of the GYxxØ trafficking motif and reveal, paradoxically, that viral control is enhanced in a macaque species typically predisposed to more pathogenic manifestations of simian immunodeficiency virus (SIV) infection. IMPORTANCE: The pathogenesis of human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) reflects a balance between viral replication, host innate and adaptive antiviral immune responses, and sustained immune activation that in humans and Asian macaques is associated with persistent viremia, immune escape, and AIDS. Among nonhuman primates, pig-tailed macaques following SIV infection are predisposed to more rapid disease progression than are rhesus macaques. Here, we show that disruption of a conserved tyrosine-based cellular trafficking motif in the viral transmembrane envelope glycoprotein cytoplasmic tail leads in pig-tailed macaques to a unique phenotype in which high levels of acute viral replication are followed by elite control, robust cellular responses in mucosal tissues, and no disease. Paradoxically, control of this virus in rhesus macaques is only partial, and progression to AIDS occurs. This novel model should provide a powerful tool to help identify host-specific determinants for viral control with potential relevance for vaccine development.


Assuntos
Motivos de Aminoácidos , Linfócitos T CD4-Positivos/imunologia , Imunidade nas Mucosas , Macaca nemestrina/virologia , Deleção de Sequência , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Proteínas do Envelope Viral/imunologia , Animais , Linfócitos T CD4-Positivos/virologia , Progressão da Doença , Feminino , Expressão Gênica , Intestinos/imunologia , Intestinos/virologia , Macaca mulatta/virologia , Masculino , Dados de Sequência Molecular , Mucosa/imunologia , Mucosa/virologia , Sinais Direcionadores de Proteínas , Estrutura Terciária de Proteína , Transporte Proteico , Síndrome de Imunodeficiência Adquirida dos Símios/patologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/genética , Vírus da Imunodeficiência Símia/imunologia , Especificidade da Espécie , Proteínas do Envelope Viral/deficiência , Proteínas do Envelope Viral/genética , Carga Viral/genética , Carga Viral/imunologia , Viremia/imunologia , Viremia/patologia , Replicação Viral/genética , Replicação Viral/imunologia
5.
Virol J ; 11: 23, 2014 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-24507450

RESUMO

BACKGROUND: Previously, we showed that the tetraspanin membrane protein CD63 mediates both early and post-integration stages of the HIV-1 replication cycle. The temporal roles of CD63 were discerned using monoclonal antibodies and small interfering RNAs (siRNAs) to block CD63 function, and determining which of the sequential steps in HIV-1 replication were disrupted. Inhibition was shown to occur during early infection, suggestive of involvement in virus entry or reverse transcription. In addition, we have shown that treatment with CD63 siRNA post-infection, significantly inhibited virus production in supernatant, suggesting an important role for CD63 in macrophages during HIV-1 replication events occurring after proviral integration, and possibly during egress. RESULTS: In this study we used CD63 siRNA to investigate the infectivity of pseudotyped viruses (carrying an NL4-3 Env-negative luciferase backbone) in primary human macrophages. We demonstrated that lab adapted R5- and R5X4-tropic HIV-1 strains are significantly inhibited by CD63 silencing. However, the infectivity of MLV or VSV-pseudotyped strains, which enter though receptor-mediated endocytosis, is unaffected by silencing CD63. These results indicate that CD63 may support Env-mediated entry or fusion events facilitated though CD4 and CCR5. Also, antibody and siRNA-based CD63 inhibition studies indicate a potential role for CD63 following proviral integration. Further, we show that CD63 expression is key for efficient replication in primary CD4⁺ T cells, complementing our prior studies with primary human macrophages and immortalized cell lines. CONCLUSIONS: Collectively, these findings indicate that CD63 may support Env-mediated fusion as well as a late (post-integration) step in the HIV-1 replication cycle.


Assuntos
HIV-1/fisiologia , Interações Hospedeiro-Patógeno , Tetraspanina 30/metabolismo , Tetraspaninas/metabolismo , Internalização do Vírus , Replicação Viral , Células Cultivadas , Técnicas de Silenciamento de Genes , Humanos
6.
Artigo em Inglês | MEDLINE | ID: mdl-38335314

RESUMO

Background: The relationship between cannabis and inflammation among persons with HIV (PWH) remains unclear. We examined whether the cannabis metabolite 11-nor-9-carboxy THC (THC-COOH) is associated with lower levels of plasma biomarkers of inflammation, immune activation, and microbial translocation in PWH. We hypothesized that cannabis use would be associated with lower levels of plasma inflammatory biomarkers than noncannabis use. Methods: We quantified THC-COOH in plasma, with THC-COOH levels between 5.1-69.9 µg/L and ≥70 µg/L being classified as moderate and heavy cannabis use, respectively, with noncannabis use defined as undetected THC-COOH. We measured a panel of plasma biomarkers of inflammation (interleukin [IL]-1-ß, tumor necrosis factor-alpha, IL-18, IL-6, and C-reactive protein), immune activation (CD14 and CD163), and microbial translocation (iFABP2 and lipopolysaccharide binding protein [LBP]), with all biomarkers collected on the same day. We used a cross-sectional design and linear regression models to test whether cannabis use is associated with lower biomarker levels. Results: Participants were (N=107) sexual minority men with HIV (median age=32 years, IQR=28, 38), of whom 65% were virally suppressed; 36%, 44%, and 20% were classified as nonuse, moderate, and heavy cannabis, respectively. In linear regression models adjusted for viral suppression, stimulant use, and CD4 counts, heavy cannabis use was significantly associated with lower levels of log10 LBP (ß=-0.14, 95% confidence interval: -0.24 to -0.04; false discovery rate=0.0029; partial eta squared=0.07) than noncannabis users. No precise associations were observed for other biomarkers (all p>0.05). Conclusions: Our findings suggest that cannabis use may be associated with lower plasma LBP. Further work is needed to clarify the relationship between cannabis use and biomarkers of microbial translocation in PWH.

8.
Biochemistry ; 51(42): 8321-3, 2012 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-23057694

RESUMO

By combining pseudorandom bead-based aptamer libraries with conjugation chemistry, we have created next-generation aptamers, X-aptamers (XAs). Several X-ligands can be added in a directed or random fashion to the aptamers to further enhance their binding affinities for the target proteins. Here we describe the addition of a drug (N-acetyl-2,3-dehydro-2-deoxyneuraminic acid), demonstrated to bind to CD44-HABD, to a complete monothioate backbone-substituted aptamer to increase its binding affinity for the target protein by up to 23-fold, while increasing the drug's level of binding 1-million fold.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnica de Seleção de Aptâmeros/métodos , Aptâmeros de Nucleotídeos/metabolismo , Sequência de Bases , Receptores de Hialuronatos/química , Ligantes , Ácido N-Acetilneuramínico/análogos & derivados , Ácido N-Acetilneuramínico/química , Ligação Proteica
9.
Biochemistry ; 49(42): 9106-12, 2010 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-20843027

RESUMO

CD44, the primary receptor for hyaluronic acid, plays an important role in tumor growth and metastasis. CD44-hyaluronic acid interactions can be exploited for targeted delivery of anticancer agents specifically to cancer cells. Although various splicing variants of CD44 are expressed on the plasma membrane of cancer cells, the hyaluronic acid binding domain (HABD) is highly conserved among the CD44 splicing variants. Using a novel two-step process, we have identified monothiophosphate-modified aptamers (thioaptamers) that specifically bind to the CD44's HABD with high affinities. Binding affinities of the selected thioaptamers for the HABD were in the range of 180-295 nM, an affinity significantly higher than that of hyaluronic acid (K(d) above the micromolar range). The selected thioaptamers bound to CD44 positive human ovarian cancer cell lines (SKOV3, IGROV, and A2780) but failed to bind the CD44 negative NIH3T3 cell line. Our results indicated that thio substitution at specific positions of the DNA phosphate backbone results in specific and high-affinity binding of thioaptamers to CD44. The selected thioaptamers will be of great interest for further development as a targeting or imaging agent for the delivery of therapeutic payloads for cancer tissues.


Assuntos
Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/metabolismo , Receptores de Hialuronatos/química , Receptores de Hialuronatos/metabolismo , Ácido Hialurônico/metabolismo , Animais , Aptâmeros de Nucleotídeos/genética , Sequência de Bases , Sítios de Ligação , Biomarcadores Tumorais/química , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Feminino , Humanos , Receptores de Hialuronatos/genética , Técnicas In Vitro , Cinética , Camundongos , Células NIH 3T3 , Conformação de Ácido Nucleico , Neoplasias Ovarianas/metabolismo , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Técnica de Seleção de Aptâmeros
10.
Pathog Immun ; 5(1): 364-381, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33501400

RESUMO

BACKGROUND: Reduced microbiota diversity (dysbiosis) in people with HIV (PWH) likely contributes to inflammation, a driver of morbidity and mortality. We aimed to evaluate the safety and tolerability of 6 weekly oral fecal microbiota transplants (FMT) administered to reverse this dysbiosis. METHODS: Six PWH on suppressive antiretroviral therapy (ART) received 6 weekly doses of lyophilized fecal microbiota product from healthy donors. Shotgun sequencing on stool before, after last FMT, and 20 weeks thereafter was performed. Inflammation and gut permeability biomarkers were measured. RESULTS: Median age at week 0 was 39 years, CD4+ T cell count 496 cells/mm3, HIV RNA levels <20 copies/mL. FMT was safe and well-tolerated. α diversity increased in 4 participants from weeks 0 to 6, including the 3 with the lowest α diversity at week 0. At week 26, α diversity more closely resembled week 0 than week 6 in these 4 participants. Metagenomic analysis showed no consistent changes across all participants. One participant had high gut permeability and inflammation biomarker levels and low α diversity that improved between weeks 0 and 6 with a shift in distribution. CONCLUSIONS: Weekly FMT was safe and well-tolerated. α diversity increased in participants with the lowest baseline α diversity during the treatment period. Future randomized, controlled trials of FMT should consider evaluating PWH with greater inflammation, gut damage, or dysbiosis as this population may be most likely to show a significant response.ClinicalTrials.gov Identifier: NCT03329560.

11.
AIDS Res Hum Retroviruses ; 36(4): 314-323, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31838858

RESUMO

Despite antiretroviral therapy (ART), innate and adaptive immunologic damage persists in the periphery and gut. T memory stem cells (Tscm) and natural killer (NK) cells are pivotal for host defense. Tscm are memory cells capable of antigen response and self-renewal, and circulating and gut NK cell populations may facilitate HIV control. The impact of early ART on circulating and gut Tscm and NK cells is unknown. We enrolled participants who initiated ART during acute versus chronic HIV-1 infection versus no ART in chronic infection. We performed flow cytometry to identify NK and Tscm cells in the blood and rectum and polymerase chain reaction to quantify the HIV-1 reservoir in both sites. We used the Mann-Whitney U-test and Spearman correlation coefficients for analysis. Participants who started ART in acute infection had lower rectal CD56brightCD16dim cell frequencies than participants who started ART in chronic HIV-1 infection and lower CD56bright and CD56brightCD16- cell frequencies than participants with chronic infection without ART. Higher circulating NK cell, CD56-CD16bright, CD56dim, and CD56dimCD16bright frequencies correlated with higher HIV-1 DNA levels in rectal CD4+ T cells, whereas higher circulating CD4+ T cell counts correlated with higher rectal NK, CD56brightCD16dim, and CD56dimCD16bright frequencies. Peripheral CD56brightCD16- cells were inversely associated with rectal CD56-CD16bright cells. Rectal CD8+ Tscm frequencies were higher in participants without ART than participants with chronic infection on ART. Timing of ART initiation determines rectal NK cell populations, and ART may influence rectal Tscm populations. Whether the gut reservoir contributes to NK cell activation requires further study.


Assuntos
Antirretrovirais/uso terapêutico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Células Matadoras Naturais/imunologia , Reto/imunologia , Linfócitos T/imunologia , Doença Aguda , Adulto , Antirretrovirais/efeitos adversos , Contagem de Linfócito CD4 , Doenças das Artérias Carótidas/diagnóstico por imagem , HIV-1 , Fatores de Risco de Doenças Cardíacas , Humanos , Pessoa de Meia-Idade , Reto/citologia , Células-Tronco/imunologia , Adulto Jovem
12.
Sci Rep ; 9(1): 568, 2019 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-30679661

RESUMO

Retrospective studies indicate that co-infection of hepatitis C virus (HCV) and human immunodeficiency virus (HIV) accelerates hepatic fibrosis progression. We have developed a co-culture system (MLH) comprising primary macrophages, hepatic stellate cells (HSC, LX-2), and hepatocytes (Huh-7), permissive for active replication of HCV and HIV, and assessed the effect of these viral infections on the phenotypic changes and fibrogenic gene expression in LX-2 cells. We detected distinct morphological changes in LX-2 cells within 24 hr post-infection with HCV, HIV or HCV/HIV in MLH co-cultures, with migration enhancement phenotypes. Human fibrosis microarrays conducted using LX-2 cell RNA derived from MLH co-culture conditions, with or without HCV and HIV infection, revealed novel insights regarding the roles of these viral infections on fibrogenic gene expression in LX-2 cells. We found that HIV mono-infection in MLH co-culture had no impact on fibrogenic gene expression in LX-2 cells. HCV infection of MLH co-culture resulted in upregulation (>1.9x) of five fibrogenic genes including CCL2, IL1A, IL1B, IL13RA2 and MMP1. These genes were upregulated by HCV/HIV co-infection but in a greater magnitude. Conclusion: Our results indicate that HIV-infected macrophages accelerate hepatic fibrosis during HCV/HIV co-infection by amplifying the expression of HCV-dependent fibrogenic genes in HSC.


Assuntos
HIV/crescimento & desenvolvimento , Hepacivirus/crescimento & desenvolvimento , Células Estreladas do Fígado/virologia , Hepatócitos/virologia , Cirrose Hepática/fisiopatologia , Macrófagos/virologia , Replicação Viral , Movimento Celular , Forma Celular , Técnicas de Cocultura , Perfilação da Expressão Gênica , Infecções por HIV/complicações , Células Estreladas do Fígado/citologia , Células Estreladas do Fígado/fisiologia , Hepatite C Crônica/complicações , Hepatócitos/fisiologia , Humanos , Fatores Imunológicos/biossíntese , Macrófagos/fisiologia , Metaloproteinase 1 da Matriz/biossíntese , Análise em Microsséries , Modelos Teóricos
13.
Pathog Immun ; 4(1): 124-146, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31139758

RESUMO

BACKGROUND: Systemic inflammation persists in chronic HIV infection and is associated with increased rates of non-AIDS events such as cardiovascular and liver disease. Increased gut permeability and systemic exposure to microbial products are key drivers of this inflammation. Serum-derived bovine immunoglobulin/protein isolate (SBI) supports gut healing in other conditions such as inflammatory bowel disease. METHODS: In this randomized, double-blind study, participants receiving suppressive antiretroviral therapy (ART) with chronic diarrhea received placebo or SBI at 2.5 g BID or 5 g BID for 4 weeks, followed by a 20-week placebo-free extension phase with SBI at either 2.5 or 5 g BID. Intestinal fatty acid binding protein (I-FABP), zonulin, flagellin, lipopolysaccharide (LPS) and LPS-binding protein, and inflammatory markers were measured by ELISA or multiplex assays. Non-parametric tests were used for analysis. RESULTS: One hundred three participants completed the study. By week 24 SBI significantly decreased circulating levels of I-FABP (-0.35 ng/µL, P=0.002) and zonulin (-4.90 ng/µL, P=0.003), suggesting improvement in gut damage, and interleukin-6 (IL-6) (-0.40 pg/µL, P=0.002), reflecting improvement in systemic inflammation. In participants with the lowest quartile of CD4+ T-cell counts at baseline (189-418 cells/µL), CD4+ T-cell counts increased significantly (26 cells/µL; P=0.002). CONCLUSIONS: Oral SBI may decrease inflammation and warrants further exploration as a potential strategy to improve gut integrity and decrease systemic inflammation among persons receiving prolonged suppressive ART.

14.
Am J Trop Med Hyg ; 101(5): 1009-1017, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31482782

RESUMO

Stunting, defined as height-for-age Z score equal to or lower than -2, is associated with increased childhood mortality, cognitive impairment, and chronic diseases. The aim of the study was to investigate the relationship between linear growth, intestinal damage, and systemic inflammation in infants at risk of stunting. We followed up 78 infants aged 5-12 months living in rural areas of Peru for 6 months. Blood samples for biomarkers of intestinal damage (intestinal fatty-acid-binding protein [I-FABP] and zonulin) and systemic inflammation (interleukin-1ß, interleukin-6, tumor necrosis factor α [TNF-α], soluble CD14, and lipopolysaccharide-binding protein [LBP]) and fecal samples for microbiome analysis were collected at baseline and closure of the study. The children's growth and health status were monitored through biweekly home visits by trained staff. Twenty-one percent of the children became stunted: compared with non-stunted children, they had worse nutritional parameters and higher levels of serum I-FABP at baseline. The likelihood of becoming stunted was strongly associated with an increase in sCD14 over time; LBP and TNF-α showed a trend toward increase in stunted children but not in controls. The fecal microbiota composition of stunted children had an increased beta diversity compared with that of healthy controls throughout the study. The relative abundance of Ruminococcus 1 and 2, Clostridium sensu stricto, and Collinsella increased in children becoming stunted but not in controls, whereas Providencia abundance decreased. In conclusion, stunting in our population was preceded by an increase in markers of enterocyte turnover and differences in the fecal microbiota and was associated with increasing levels of systemic inflammation markers.


Assuntos
Microbioma Gastrointestinal , Transtornos do Crescimento/etiologia , Enteropatias/patologia , Mucosa Intestinal/patologia , Desenvolvimento Infantil , Estudos de Coortes , Citocinas/genética , Citocinas/metabolismo , Fezes/microbiologia , Feminino , Regulação da Expressão Gênica , Transtornos do Crescimento/epidemiologia , Humanos , Lactente , Enteropatias/epidemiologia , Masculino , Estado Nutricional , Peru , Projetos Piloto
15.
AIDS ; 33(15): 2289-2298, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31764094

RESUMO

BACKGROUND: We aimed to characterize the impact of antiretroviral therapy (ART) initiation on gastrointestinal-associated lymphoid tissue at various sites along the gastrointestinal site. METHODOLOGY: Peripheral blood and duodenal and rectal biopsies were obtained from 12 HIV to 33 treatment-naive HIV participants at baseline and after 9 months ART. Tissue was digested for immunophenotyping. Inflammatory, bacterial translocation and intestinal damage markers were measured in plasma. RESULTS: Twenty-six HIV patients completed follow-up. The lowest reconstitution of CD4 T cells and the lowest CD4/CD8 ratio during ART compared with blood were observed in the duodenum with the rectum being either intermediate or approaching blood levels. Regulatory T cells were in higher proportions in the duodenum than the rectum and neither declined significantly during ART. Several correlations with biomarkers of microbial translocation were observed including increases in lipoteichoic acid levels, which reflects Gram-positive bacterial translocation, correlated with increases in %CD4 T cells in the duodenum (Rho 0.773, P = 0.033), and with decreases in duodenal regulatory T-cell populations (Rho -0.40, P = 0.045). CONCLUSION: HIV-mediated immunological disruption is greater in the duodenum than rectum and blood before and during ART. Small intestine damage may represent a unique environment for T-cell depletion, which might be attenuated by interaction with Gram-positive bacteria.


Assuntos
Duodeno/imunologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Reconstituição Imune , Reto/imunologia , Adulto , Terapia Antirretroviral de Alta Atividade , Biópsia , Sangue/imunologia , Relação CD4-CD8 , Linfócitos T CD4-Positivos/imunologia , Feminino , Humanos , Imunofenotipagem , Mucosa Intestinal/imunologia , Modelos Lineares , Ativação Linfocitária , Masculino
16.
Biochem Biophys Res Commun ; 366(3): 752-7, 2008 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-18078807

RESUMO

The most abundant base-substitution mutation resulting from oxidative damage to DNA is the GC to AT transition mutation. 5-hydroxyuracil (5-OHU), produced by the oxidative deamination of cystosine, has been established as the major chemical precursor for this most abundant transition mutation. Results from NMR spectroscopy and UV melting experiments show that 5-OHU would form the most stable pair with G, and the least stable pair with C. The hydroxyl group in the 5th position of the 5-OHU residue may play a role in increasing the stability of the 5-OHU:G pair over the normal Watson-Crick pair, the 5-OHU:A. The 5-OHU:C base pair would be least stable, and would destabilize the base-stacking in the duplex. Our results explain why certain DNA polymerases preferentially incorporate G opposite to 5-OHU over A and why C does not get incorporated against 5-OHU during DNA replication in vivo.


Assuntos
Pareamento de Bases , Citosina/química , DNA/química , Modelos Químicos , Modelos Moleculares , Uracila/análogos & derivados , Simulação por Computador , Oxirredução , Uracila/química
17.
PLoS One ; 13(5): e0196395, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29746485

RESUMO

BACKGROUND: People with HIV are at for metabolic syndrome (MetS) and fatty liver disease, but the role of Antiretroviral therapy (ART) is poorly understood. MetS and fatty liver disease been associated with changes in adiponectin, soluble ST2 (sST2), chitinase 3-like 1 (Chi3L1), hyaluronic acid (HA), tissue inhibitor of metalloproteinase-1 (TIMP-1), lysyl oxidase-like-2 (LOXL2) and transforming growth factor ß (TGF-ß) concentrations in HIV-uninfected populations. Protease (PI) and non-nucleoside reverse transcriptase inhibitors (NNRTI) may contribute to these comorbidities, but the effects of switching from PI- or NNRTI to raltegravir (RAL) on these biomarkers is unknown. METHODS: Cryopreserved plasma was obtained from a completed, prospective trial of HIV-infected women with central adiposity on NNRTI- or PI-based ART during which they were randomized to remain on their current ART or switch to a RAL based regimen. Biomarker concentrations were quantified using ELISA and Multiplex assays at baseline and 24 weeks after randomization. Wilcoxon-signed rank test evaluated within-group changes, Spearman and linear regression models evaluated correlations between biomarkers and clinical covariates. RESULTS: Participants had a median age of 43 years, CD4+ T lymphocyte count 558 cells/mm3 and BMI 32 kg/m2; 35% met criteria for MetS. At baseline, higher adiponectin levels correlated with higher Chi3L1 levels (r = 0.42, p = 0.02), as did declines after 24 weeks (r = 0.40, p = 0.03). Changes in sST2 correlated with changes in Chi3L1 (r = 0.43, p = 0.02) and adiponectin (r = 0.40, p = 0.03). Adiponectin and Chi3L1 levels decreased significantly in women switched to RAL vs continue PI/NNRTI. CONCLUSION: In women with HIV and central obesity, the hepatic steatosis/fibrosis marker Chi3L1 and adiponectin decrease in conjunction with sST2 decreases following switch to RAL. Whether switching from NNRTI/PI-based regimens to RAL can improve hepatic steatosis and dysmetabolism requires further study. TRIAL REGISTRATION: Clinicaltrials.gov NCT00656175.


Assuntos
Adiponectina/uso terapêutico , Proteína 1 Semelhante à Quitinase-3/efeitos dos fármacos , Raltegravir Potássico/farmacologia , Adiponectina/sangue , Adiponectina/metabolismo , Adiponectina/farmacologia , Adulto , Aminoácido Oxirredutases/análise , Aminoácido Oxirredutases/sangue , Fármacos Anti-HIV/uso terapêutico , Biomarcadores/sangue , Contagem de Linfócito CD4 , Proteína 1 Semelhante à Quitinase-3/metabolismo , Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/metabolismo , Feminino , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/uso terapêutico , Humanos , Síndrome Metabólica/metabolismo , Pessoa de Meia-Idade , Obesidade/fisiopatologia , Estudos Prospectivos , Raltegravir Potássico/metabolismo , Raltegravir Potássico/uso terapêutico , Inibidores da Transcriptase Reversa/farmacologia , Inibidores da Transcriptase Reversa/uso terapêutico , Inibidor Tecidual de Metaloproteinase-1/análise , Inibidor Tecidual de Metaloproteinase-1/sangue , Carga Viral
18.
Pathog Immun ; 2(2): 239-252, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28782046

RESUMO

BACKGROUND: Incomplete immune reconstitution may occur despite successful antiretroviral therapy (ART). Gut-associated lymphoid tissue (GALT) fibrosis may contribute via local CD4+ T lymphocyte depletion, intestinal barrier disruption, microbial translocation, and immune activation. METHODS: In a cross-sectional analysis, we measured circulating fibrosis biomarker levels on cryopreserved plasma from adult HIV-infected (HIV+) SCOPE study participants on suppressive ART who also had fibrosis quantification on recto-sigmoid biopsies. Relationships among biomarker levels, clinical and demographic variables, GALT lymphoid aggregate (LA) collagen deposition, and LA CD4+ T lymphocyte density were analyzed using simple regression. Biomarker levels were also compared to levels in HIV+ viremic SCOPE participants and a convenience sample of HIV-uninfected (HIV-) samples. RESULTS: HIV+ aviremic participants (n = 39) were 92% male and 41% non-white, with median age 48 years, CD4+ T lymphocyte count 277 cells/mm3, and 17 years since HIV diagnosis. Most biomarkers were lower in HIV- (n = 36) vs HIV+ aviremic individuals, although CXCL4 levels were higher. HIV+ viremic individuals (N = 18) had higher median TGF-ß3, CIC-C1Q, and TIMP-1 (P < 0.05) and lower LOXL2 levels (P = 0.08) than HIV+ aviremic individuals. Only higher LOXL2 levels correlated with more GALT collagen deposition (R = 0.44, P= 0.008) and lower LA CD4+ T lymphocyte density (R = -0.32, P = 0.05) among aviremic individuals. CONCLUSIONS: Circulating LOXL2 levels may be a noninvasive measure of intestinal fibrosis and GALT CD4+ T lymphocyte depletion in treated HIV infection. LOXL2 crosslinks elastin and collagen, and elevated LOXL2 levels occur in pathologic states, making LOXL2 inhibition a potential interventional target for intestinal fibrosis and its sequelae.

19.
J Reprod Immunol ; 120: 20-26, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28399439

RESUMO

Several cytokines have been detected in human milk but their relative concentrations differ among women and vary over time in the same person. The drivers of such differences have been only partially identified, while the effect of luminal cytokines in the fine-regulation of the intestinal immune system is increasingly appreciated. The aim of this study was to investigate the associations between obstetrical complications and human milk cytokine profiles in a cohort of Peruvian women giving birth to Low Birth Weight (LBW) infants. Colostrum and mature human milk samples were collected from 301 Peruvian women bearing LBW infants. The concentration of twenty-three cytokines was measured using the Luminex platform. Ninety-nine percent of women had at least one identified obstetrical complication leading to intra-uterine growth restriction and/or preterm birth. Median weight at birth was 1,420g; median gestational age 31 weeks. A core of 12 cytokines, mainly involved in innate immunity and epithelial cell integrity, was detectable in most samples. Maternal age, maternal infection, hypertensive disorders, preterm labor, and premature rupture of membranes were associated with specific cytokine profiles both in colostrum and mature human milk. Mothers of Very LBW (VLBW) neonates had significantly higher concentrations of chemokines and growth factor cytokines both in their colostrum and mature milk compared with mothers of larger neonates. Thus, maternal conditions affecting pregnancy duration and in utero growth are also associated with specific human milk cytokine signatures.


Assuntos
Citocinas/metabolismo , Recém-Nascido de Baixo Peso , Leite Humano/metabolismo , Complicações Cardiovasculares na Gravidez/epidemiologia , Nascimento Prematuro/epidemiologia , Adulto , Estudos de Coortes , Feminino , Humanos , Imunidade Inata , Recém-Nascido , Lactação/imunologia , Idade Materna , Peru , Gravidez , Complicações Cardiovasculares na Gravidez/imunologia , Nascimento Prematuro/imunologia , Fatores de Risco , Transcriptoma , Adulto Jovem
20.
AIDS Res Hum Retroviruses ; 32(12): 1205-1209, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27344921

RESUMO

HIV-1-infected persons have increased risk of serious non-AIDS events (SNAEs) despite suppressive antiretroviral therapy. Increased circulating levels of soluble CD14 (sCD14), soluble CD163 (sCD163), and interleukin-6 (IL-6) at a single time point have been associated with SNAEs. However, whether changes in these biomarker levels predict SNAEs in HIV-1-infected persons is unknown. We hypothesized that greater decreases in inflammatory biomarkers would be associated with fewer SNAEs. We identified 39 patients with SNAEs, including major cardiovascular events, end stage renal disease, decompensated cirrhosis, non-AIDS-defining malignancies, and death of unknown cause, and age- and sex-matched HIV-1-infected controls. sCD14, sCD163, and IL-6 were measured at study enrollment (T1) and proximal to the event (T2) or equivalent duration in matched controls. Over ∼34 months, unchanged rather than decreasing levels of sCD14 and IL-6 predicted SNAEs. Older age and current illicit substance abuse, but not HCV coinfection, were associated with SNAEs. In a multivariate analysis, older age, illicit substance use, and unchanged IL-6 levels remained significantly associated with SNAEs. Thus, the trajectories of sCD14 and IL-6 levels predict SNAEs. Interventions to decrease illicit substance use may decrease the risk of SNAEs in HIV-1-infected persons.


Assuntos
Biomarcadores/sangue , Infecções por HIV/complicações , Infecções por HIV/patologia , Interleucina-6/sangue , Receptores de Lipopolissacarídeos/sangue , Adulto , Idoso , Antígenos CD/sangue , Antígenos de Diferenciação Mielomonocítica/sangue , Doenças Cardiovasculares/epidemiologia , Feminino , Humanos , Falência Hepática/epidemiologia , Masculino , Pessoa de Meia-Idade , Mortalidade , Neoplasias/epidemiologia , Prognóstico , Estudos Prospectivos , Receptores de Superfície Celular/sangue , Insuficiência Renal/epidemiologia , Estudos Retrospectivos , Análise de Sobrevida
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