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1.
iScience ; 26(10): 107915, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37790281

RESUMO

Older individuals and people with HIV (PWH) were prioritized for COVID-19 vaccination, yet comprehensive studies of the immunogenicity of these vaccines and their effects on HIV reservoirs are not available. Our study on 68 PWH and 23 HIV-negative participants aged 55 and older post-three vaccine doses showed equally strong anti-spike IgG responses in serum and saliva through week 48 from baseline, while PWH salivary IgA responses were low. PWH had diminished live-virus neutralization responses after two vaccine doses, which were 'rescued' post-booster. Spike-specific T cell immunity was enhanced in PWH with normal CD4+ T cell count, suggesting Th1 imprinting. The frequency of detectable HIV viremia increased post-vaccination, but vaccines did not affect the size of the HIV reservoir in most PWH, except those with low-level viremia. Thus, older PWH require three doses of COVID-19 vaccine for maximum protection, while individuals with unsuppressed viremia should be monitored for adverse reactions from HIV reservoirs.

2.
bioRxiv ; 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37502977

RESUMO

Older individuals and people with HIV (PWH) were prioritized for COVID-19 vaccination, yet comprehensive studies of the immunogenicity of these vaccines and their effects on HIV reservoirs are not available. We followed 68 PWH aged 55 and older and 23 age-matched HIV-negative individuals for 48 weeks from the first vaccine dose, after the total of three doses. All PWH were on antiretroviral therapy (cART) and had different immune status, including immune responders (IR), immune non-responders (INR), and PWH with low-level viremia (LLV). We measured total and neutralizing Ab responses to SARS-CoV-2 spike and RBD in sera, total anti-spike Abs in saliva, frequency of anti-RBD/NTD B cells, changes in frequency of anti-spike, HIV gag/nef-specific T cells, and HIV reservoirs in peripheral CD4 + T cells. The resulting datasets were used to create a mathematical model for within-host immunization. Various regimens of BNT162b2, mRNA-1273, and ChAdOx1 vaccines elicited equally strong anti-spike IgG responses in PWH and HIV - participants in serum and saliva at all timepoints. These responses had similar kinetics in both cohorts and peaked at 4 weeks post-booster (third dose), while half-lives of plasma IgG also dramatically increased post-booster in both groups. Salivary spike IgA responses were low, especially in INRs. PWH had diminished live virus neutralizing titers after two vaccine doses which were 'rescued' after a booster. Anti-spike T cell immunity was enhanced in IRs even in comparison to HIV - participants, suggesting Th1 imprinting from HIV, while in INRs it was the lowest. Increased frequency of viral 'blips' in PWH were seen post-vaccination, but vaccines did not affect the size of the intact HIV reservoir in CD4 + T cells in most PWH, except in LLVs. Thus, older PWH require three doses of COVID-19 vaccine to maximize neutralizing responses against SARS-CoV-2, although vaccines may increase HIV reservoirs in PWH with persistent viremia.

4.
J Acquir Immune Defic Syndr ; 89(2): 199-207, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34693932

RESUMO

OBJECTIVE: To assess whether probiotic supplementation may reduce disease-linked systemic immune activation in people living with HIV with the immunologic nonresponder phenotype. DESIGN: Phase 2b, randomized, double-blind, placebo-controlled pilot trial. METHODS: HIV-positive individuals with blood CD4+ T-cell counts <350/mm3 despite viral suppression were randomized to 2:1 to receive De Simone Formulation Probiotic (DSFP; "Visbiome" commercially) or placebo for 48 weeks; target enrollment was 36 patients. The primary endpoint was the change in blood CD8+ T-cell coexpression of human leukocyte antigen-DR isotype and CD38 ("CD8 activation"). Secondary endpoints included biomarkers of inflammation, immune reconstitution, bacterial translocation, and gut permeability. Adjusted linear regression and linear mixed regression methods evaluated the differences between study arms from baseline to week 48. Study monitoring was performed by the CIHR Canadian HIV Trials Network Data Safety Monitoring Committee. RESULTS: Nineteen patients received DSFP, whereas 10 received placebo. One probiotic arm patient withdrew early. Blood CD8 activation increased 0.82 percentage points (pp) in the probiotic arm (95% confidence interval: -1.23 to 2.87;) and decreased by 2.06 pp in the placebo arm (-4.81 to 0.70; between arms P = 0.097). CD4+ T-cell activation (%HLA-DR+) decreased in the placebo arm [-3.79 pp (-7.32 to -0.26)] but increased in the probiotic arm [1.64 (-0.98 to 4.26); between arms P = 0.018]. No differences were observed in plasma or urine biomarkers of inflammation or microbial translocation. CONCLUSIONS: Blood immune activation markers in immunologic nonresponder individuals on effective antiretroviral treatment were not reduced by supplementation with DSFP; CD4+ T-cell activation may have been increased.


Assuntos
Infecções por HIV , Probióticos , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos , Canadá , Antígenos HLA-DR , Humanos , Probióticos/uso terapêutico
5.
Front Nutr ; 8: 736816, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34881278

RESUMO

Immunologic non-responders (INRs) are a subset of individuals living with HIV who have suboptimal blood CD4+ T cell recovery despite effective antiretroviral therapy (ART). They are at an increased risk of serious non-AIDS co-morbidities and death, and demonstrate enhanced systemic immune activation. In other populations diet has been correlated with markers of systemic inflammation through the Diet Inflammatory Index (DII), but this association has not been studied in persons living with HIV (PLWH). Blood was collected from 28 INR PLWH with a blood CD4+ T cell count <350/µL despite ≥2 years of effective ART. Participants completed a Canadian Diet History Questionnaire, and their responses were used to calculate the DII. Plasma inflammatory markers (IFNγ, TNF, IL-6, sVCAM, D-dimer, sCD14 and CRP) were assayed by ELISA, cellular immune activation (HLA-DR and CD38 on CD4+ and CD8+ T cells) was quantified using flow cytometry, and small bowel permeability assessed by calculation of the urine LacMan ratio after drinking a mix of lactulose and mannitol. Participants were a median age of 57 years, had been on effective ART for 15 years, and the median DII was -1.91 (range of -3.78 to +2.23). No correlation was observed between DII and plasma markers of inflammation, levels of T cell activation, gut permeability, or the biomarker of bacterial translocation sCD14. Self-reported alcohol intake, a potential confounder of the relationship between diet and inflammatory biomarkers, was also not associated with systemic inflammation or gut permeability. Our findings suggest that other mechanisms, rather than diet, are likely to be the major driver of systemic inflammation in INR individuals.

6.
Artigo em Inglês | MEDLINE | ID: mdl-30984752

RESUMO

Our national data and infrastructure security issues affecting the "bioeconomy" are evolving rapidly. Simultaneously, the conversation about cyber security of the U.S. food and agricultural system (cyber biosecurity) is incomplete and disjointed. The food and agricultural production sectors influence over 20% of the nation's economy ($6.7T) and 15% of U.S. employment (43.3M jobs). The food and agricultural sectors are immensely diverse and they require advanced technologies and efficiencies that rely on computer technologies, big data, cloud-based data storage, and internet accessibility. There is a critical need to safeguard the cyber biosecurity of our bio economy, but currently protections are minimal and do not broadly exist across the food and agricultural system. Using the food safety management Hazard Analysis Critical Control Point system concept as an introductory point of reference, we identify important features in broad food and agricultural production and food systems: dairy, food animals, row crops, fruits and vegetables, and environmental resources (water). This analysis explores the relevant concepts of cyber biosecurity from food production to the end product user (such as the consumer) and considers the integration of diverse transportation, supplier, and retailer networks. We describe common challenges and unique barriers across these systems and recommend solutions to advance the role of cyber biosecurity in the food and agricultural sectors.

7.
J Food Prot ; 81(7): 1063-1067, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29877732

RESUMO

A multiyear survey of 31 ready-to-eat (RTE) food processing plants in the United States was conducted to determine the incidence of Listeria spp. in various RTE production environments. Samples were collected from 22 RTE plants regulated by the U.S. Department of Agriculture's Food Safety and Inspection Service (FSIS) and from 9 RTE food plants regulated by the U.S. Department of Health and Human Services' Food and Drug Administration (FDA). Only nonfood contact surfaces in the RTE manufacturing areas with exposed RTE product were sampled. Each sample was individually analyzed for the presence of Listeria spp. by using a PCR-based rapid assay. In total, 4,829 samples were collected from various locations, including freezers, equipment framework, floors, walls, wall-floor junctures, drains, floor mats, doors, and cleaning tools. Nine (29%) of the facilities had zero samples positive for Listeria spp. in the production environment, whereas 22 (71%) had one or more samples positive for Listeria spp. The total incidence of Listeria spp. in all RTE food plants was 4.5%. The positive rate in plants regulated by the FSIS ranged from 0 to 9.7%, whereas the positive rate in plants regulated by the FDA ranged from 1.2 to 36%.


Assuntos
Contaminação de Alimentos/análise , Indústria de Processamento de Alimentos/normas , Listeria , Manipulação de Alimentos , Humanos , Incidência , Listeria/isolamento & purificação , Estados Unidos , United States Food and Drug Administration
9.
J Virus Erad ; 3(4): 212-217, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29057085

RESUMO

INTRODUCTION: Antiretroviral therapy (ART) does not cure HIV infection due to the persistence of HIV reservoirs in long-lived memory CD4 T cells present in the blood, lymph nodes, intestinal tract, and other tissues. Interest grows in obtaining gut-tissue samples for HIV persistence studies, which poses an ethical challenge to provide study volunteers with adequate information on risks and benefits. Herein we assess the risks and benefits of undergoing gut biopsy procedures for HIV pathogenesis and reservoir studies. METHODS: A group discussion was organised with physicians and community representatives on performing either a flexible sigmoidoscopy or a colonoscopy. Consensus was reached on conducting colonoscopy in persons ≥50 years. Thirty HIV-infected, ART-treated and nine uninfected participants were recruited. Colonoscopy was performed to collect 30 gut mucosal biopsies. When present, polyps were removed and abnormal mucosal findings were biopsied for pathological analysis. Participants were interviewed on potential discomfort following colonoscopic examination. RESULTS: The HIV-infected and uninfected groups were comparable in terms of age and gender with more men who have sex with men (MSM) in the former group. Abnormal colonoscopic findings were observed in 43.6% of all the participants and did not differ by HIV status. In total, 24 polyps were removed with a higher mean number of polyps removed in HIV-infected versus uninfected participants (1.7 vs 1.0, P=0.013). The number of polyps marginally correlated with inverted CD4:CD8 ratio. Based on our findings, colonoscopic examination was safe to use for gut biopsy procedures where almost half of the participants had polyps removed. CONCLUSION: Participation in the study provided colon cancer screening as an ancillary benefit that participants could have received in standard medical care, thus mitigating burdens of invasive procedures. Dialogue between community representatives and clinical researchers can increase participation and advance HIV cure research.

10.
J Acquir Immune Defic Syndr ; 75(1): e1-e7, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-27984556

RESUMO

BACKGROUND: Aging and increasing comorbidity is changing the end-of-life experience of people living with HIV (PLHIV) in the developed world. We quantified, at a population level, the receipt of health care services and associated costs across a comprehensive set of sectors among decedents with and without HIV. METHODS: We conducted a retrospective population-level observational study of all decedents in Ontario and their receipt of health care services, captured through linked health administrative databases, between April 1, 2010 and March 31, 2013. We identified PLHIV using a validated algorithm. We described the characteristics of PLHIV and their receipt of health care services and associated costs by health care sector in the last year of life. RESULTS: We observed 264,754 eligible deaths, 570 of whom had HIV. PLHIV were significantly younger than those without HIV (mean age of death 56.1 years vs. 76.6 years, [P < 0.01]). PLHIV spent a mean of 20.0 days in an acute care hospital in the last 90 days of life compared with 12.1 days for decedents without HIV (P < 0.01); after adjustment, HIV was associated with 4.5 more acute care days (P < 0.01). Mean cost of care in the last year was significantly higher among PLHIV ($80,885.62 vs. $53,869.77), mostly attributable to acute care costs. INTERPRETATION: PLHIV in Ontario are dying younger, spending more time and dying more often in hospital, and incur significantly increased costs before death. Greater involvement of community-based palliative care may improve the dying experience for this complex population.


Assuntos
Infecções por HIV/tratamento farmacológico , Serviços de Saúde para Idosos , Cuidados Paliativos/economia , Cuidados Paliativos/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Custos de Cuidados de Saúde , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Ontário , Estudos Retrospectivos , Adulto Jovem
11.
HIV Clin Trials ; 17(4): 147-57, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27267710

RESUMO

OBJECTIVES: Despite substantial improvements in HIV outcomes with combination antiretroviral therapy (cART), morbidity and mortality remain above population norms. The gut mucosal immune system is not completely restored by cART, and the resultant microbial translocation may contribute to chronic inflammation, inadequate CD4 T-cell recovery, and increased rates of serious non-AIDS events. Since the microbial environment surrounding a CD4 T cell may influence its development and function, we hypothesize that probiotics provided during cART might reduce inflammation and improve gut immune health in HIV-positive treatment-naïve individuals (PROOV IT I) and individuals with suboptimal CD4 recovery on cART (PROOV IT II). METHODS: These prospective, double-blinded, randomized, placebo-controlled, multicenter pilot studies will assess the impact of the probiotic Visbiome at 900 billion bacteria daily. Forty HIV positive cART-naïve men will be randomized in the PROOV IT I study, coincident with antiretroviral initiation, and be followed for 24 weeks. In PROOV IT II, 36 men on cART, but with a CD4 T-cell count below 350 cells/mm(3) will be followed for 48 weeks. The primary outcome for both studies is the comparison of blood CD8 T-cell immune activation. Secondary analyses will include comparison of blood inflammatory biomarkers, microbial translocation, blood and gut immunology and HIV levels, the bacterial community composition, diet, intestinal permeability, and the safety, adherence and tolerability of the study product. DISCUSSION: These studies will evaluate the ability of probiotics as a safe and tolerable therapeutic intervention to reduce systemic immune activation and to accelerate gut immune restoration in people living with HIV.


Assuntos
Protocolos Clínicos , Gastroenterite/imunologia , Gastroenterite/terapia , Infecções por HIV/imunologia , Imunidade nas Mucosas , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Probióticos/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Biomarcadores , Contagem de Linfócito CD4 , Gastroenterite/patologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Humanos , Imunomodulação , Mucosa Intestinal/metabolismo , Mucosa Intestinal/virologia , Ativação Linfocitária/imunologia , Permeabilidade , Projetos de Pesquisa
12.
J Virus Erad ; 1(4): 276-81, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27482425

RESUMO

The International AIDS Society (IAS) convened the Towards an HIV Cure Symposium on 18-19 July 2015 in Vancouver, Canada, bringing together researchers and community to discuss the most recent advances in our understanding of HIV latency, reservoirs and a summary of the current clinical approaches towards an HIV cure. The symposium objectives were to: (1) gather researchers and stakeholders to present, review, and discuss the latest research towards an HIV cure; (2) promote cross-disciplinary global interactions between basic, clinical and social scientists; and (3) provide a platform for sharing information among scientists, clinicians, funders, media and civil society. The symposium examined basic molecular science and animal model data, and emerging and ongoing clinical trial results to prioritise strategies and determine the viral and immune responses that could lead to HIV remission without antiretroviral therapy. This report summarises some of the major findings discussed during the symposium.

14.
J Org Chem ; 63(8): 2434-2441, 1998 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-11672101

RESUMO

Several nitrobenzyl-based photosensitive phosphoramide mustards were synthesized. The nitrobenzyl moiety was structurally varied to find the most promising prodrug candidates in respect to photorelease and activity of the alkylating species. The synthesis of these compounds proved to be applicable even in regard to compounds with additional functionalization. The target molecules 13a,b to 14 exhibited the expected red shift in their absorption spectra maximum compared to the parent nitrobenzyl moiety. As seen by UV and (31)P NMR spectroscopy, the phosphoramide mustard was quickly liberated upon irradiation with mercury arc lamps. Assaying the structurally different prodrugs on their alkylating activity showed that compounds 13b and 14, derived from secondary benzyl alcohols, are promising prodrug candidates. Their water solubility and the possibility of attaching macromolecules are encouraging vis-à-vis future investigations on their in vitro cytotoxicity.

15.
J Food Prot ; 59(8): 803-807, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31159130

RESUMO

This study was conducted to determine the levels of Campylobacter jejuni , Campylobacter coli , Salmonella , Klebsiella pneumoniae , and Escherichia coli O157:H7 in fresh hand-picked blue crab ( Callinectes sapidus ) meat. An attempt was made to correlate these selected pathogens and general microbial quality to processors' sanitation practices and facility size. Hand-picked crabmeat samples from 12 blue-crab-processing facilities in the Chesapeake Bay region were collected and analyzed. Twenty samples from each of the different facilities were collected on different processing days. Facilities were chosen on the basis of production levels and Virginia Department of Health inspection scores as an indicator of sanitation practices (excellent, ≥94.5, acceptable, <94.5). All samples were tested between 16 h and 36 h after collection. Campylobacter jejuni was isolated from 36 (15%) of the 240 samples and Campylobacter coli was isolated from 14 (5.8%). Quantitative levels in all case were below limits of detection (<0.30 MPN/g). Klebsiella pneumoniae was isolated from a total of 51 (21%) samples. Counts ranged from less than 0.30 to 4.3 MPN/g. Aerobic plate counts ranged from 7.4 × 103 to 4.6 × 108 CFU/g with coliform counts ranging from <0.3 to 32.8 MPN/g. Fecal coliform levels were <0.3 to 2.26 MPN/g and Escherichia coli from <0.3 to 0.77 MPN/g. Salmonella spp. and Escherichia coli O157:H7 were not detected in any of the 240 samples analyzed. No significant differences (P < 0.05) between size and inspection scores were observed for general microbial quality or the presence of Klebsiella pneumoniae or Campylobacter species.

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