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1.
Blood ; 138(2): 122-135, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-33690816

RESUMO

Chimeric antigen receptor (CAR)-T-cell therapeutic efficacy is associated with long-term T-cell persistence and acquisition of memory. Memory-subset formation requires T-cell factor 1 (TCF-1), a master transcription factor for which few regulators have been identified. Here, we demonstrate using an immune-competent mouse model of B-cell acute lymphoblastic leukemia (ALL; B-ALL) that Regnase-1 deficiency promotes TCF-1 expression to enhance CAR-T-cell expansion and memory-like cell formation. This leads to improved CAR-T-mediated tumor clearance, sustained remissions, and protection against secondary tumor challenge. Phenotypic, transcriptional, and epigenetic profiling identified increased tumor-dependent programming of Regnase-1-deficient CAR-T cells into TCF-1+ precursor exhausted T cells (TPEX) characterized by upregulation of both memory and exhaustion markers. Regnase-1 directly targets Tcf7 messenger RNA (mRNA); its deficiency augments TCF-1 expression leading to the formation of TPEX that support long-term CAR-T-cell persistence and function. Regnase-1 deficiency also reduces exhaustion and enhances the activity of TCF-1- CAR-T cells. We further validate these findings in human CAR-T cells, where Regnase-1 deficiency mediates enhanced tumor clearance in a xenograft B-ALL model. This is associated with increased persistence and expansion of a TCF-1+ CAR-T-cell population. Our findings demonstrate the pivotal roles of TPEX, Regnase-1, and TCF-1 in mediating CAR-T-cell persistence and recall responses, and identify Regnase-1 as a modulator of human CAR-T-cell longevity and potency that may be manipulated for improved therapeutic efficacy.


Assuntos
Imunoterapia Adotiva , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Ribonucleases/metabolismo , Fator 1 de Transcrição de Linfócitos T/metabolismo , Linfócitos T/imunologia , Animais , Antígenos CD19/metabolismo , Linhagem Celular Tumoral , Reprogramação Celular , Modelos Animais de Doenças , Epigênese Genética , Humanos , Imunocompetência/imunologia , Memória Imunológica , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fenótipo , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia
2.
Eur J Immunol ; 51(6): 1482-1493, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33788263

RESUMO

The dimeric cytokine IL-12 is important in the control of various infections but also contributes to the pathology of certain diseases making it a potential target for therapy. However, its specific inhibition with antibodies is complicated by the fact that its two subunits are present in other cytokines: p40 in IL-23 and p35 in IL-35. This has led to erroneous conclusions like the alleged implication of IL-12 in experimental autoimmune encephalomyelitis (EAE). Here, we report the development of a mouse anti-mouse IL-12 vaccine and the production of monoclonal antibodies (mAbs) that do not react with p40 or p35 (in IL-35) but specifically recognize and functionally inhibit the IL-12 heterodimer. Using one of these mAbs, MM12A1.6, that strongly inhibited IFN-γ production and LPS-induced septic shock after viral infection, we demonstrate the critical role played by IL-12 in the rejection of male skin graft by female C57BL/6 syngeneic recipients and in the clearance of an immunogenic mastocytoma tumor variant by DBA/2 mice, but not in a parent to F1 immune aggression model nor in MOG-induced EAE, which was clearly prevented by anti-p40 mAb C17.8. Given this selective inhibition of IL-12, these mAbs provide new options for reassessing IL-12 function in vivo.


Assuntos
Anticorpos Monoclonais/metabolismo , Encefalomielite Autoimune Experimental/imunologia , Rejeição de Enxerto/imunologia , Interleucina-12/metabolismo , Mastocitoma/imunologia , Esclerose Múltipla/imunologia , Infecções por Nidovirales/imunologia , Nidovirales/fisiologia , Subunidades Proteicas/metabolismo , Sepse/imunologia , Transplante de Pele , Animais , Anticorpos Monoclonais/isolamento & purificação , Modelos Animais de Doenças , Epitopos , Humanos , Hibridomas , Interleucina-12/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Neoplasias Experimentais , Subunidades Proteicas/imunologia
3.
J Appl Clin Med Phys ; 23(9): e13641, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35950259

RESUMO

The American Association of Physicists in Medicine (AAPM) is a nonprofit professional society whose primary purposes are to advance the science, education, and professional practice of medical physics. The AAPM has more than 8000 members and is the principal organization of medical physicists in the United States. The AAPM will periodically define new practice guidelines for medical physics practice to help advance the science of medical physics and to improve the quality of service to patients throughout the United States. Existing medical physics practice guidelines will be reviewed for the purpose of revision or renewal, as appropriate, on their fifth anniversary or sooner. Each medical physics practice guideline represents a policy statement by the AAPM, has undergone a thorough consensus process in which it has been subjected to extensive review, and requires the approval of the Professional Council. The medical physics practice guidelines recognize that the safe and effective use of diagnostic and therapeutic radiology requires specific training, skills, and techniques, as described in each document. Reproduction or modification of the published practice guidelines and technical standards by those entities not providing these services is not authorized. The following terms are used in the AAPM practice guidelines: Must and Must Not: Used to indicate that adherence to the recommendation is considered necessary to conform to this practice guideline. While must is the term to be used in the guidelines, if an entity that adopts the guideline has shall as the preferred term, the AAPM considers that must and shall have the same meaning. Should and Should Not: Used to indicate a prudent practice to which exceptions may occasionally be made in appropriate circumstances.


Assuntos
Elétrons , Radioterapia (Especialidade) , Humanos , Fótons , Física , Estados Unidos
4.
Age Ageing ; 50(2): 457-464, 2021 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32946561

RESUMO

IMPORTANCE: treatment of dementia in individuals with comorbidities is complex, leading to potentially inappropriate prescribing (PIP). The impact of PIP in this population is unknown. OBJECTIVE: to estimate the rate of PIP and its effect on adverse health outcomes (AHO). DESIGN: retrospective cohort. SETTING: primary care electronic health records linked to hospital discharge data from England. SUBJECTS: 11,175 individuals with dementia aged over 65 years in 2016 and 43,463 age- and sex-matched controls. METHODS: Screening Tool of Older Persons' Prescriptions V2 defined PIP. Logistic regression tested associations with comorbidities at baseline, and survival analyses risk of incident AHO, adjusted for age, gender, deprivation and 14 comorbidities. RESULTS: the dementia group had increased risk of PIP (73% prevalence; odds ratio [OR]: 1.92; confidence interval [CI]: 83-103%; P < 0.01) after adjusting for comorbidities. Most frequent PIP criteria were related to anti-cholinergic drugs and therapeutic duplication. Risk of PIP was higher in patients also diagnosed with coronary-heart disease (odds OR: 2.17; CI: 1.91-2.46; P < 0.01), severe mental illness (OR: 2.09; CI: 1.62-2.70; P < 0.01); and depression (OR: 1.81; CI: 1.62-2.01; P < 0.01). During follow-up (1 year), PIP was associated with increased all-cause mortality (hazard ratio: 1.14; CI: 1.02-1.26; P < 0.02), skin ulcer and pressure sores (hazard ratio: 1.66; CI: 1.12-2.46; P < 0.01), falls (hazard ratio: 1.37; CI: 1.15-1.63; P < 0.01), anaemia (hazard ratio: 1.61; CI: 1.10-2.38; P < 0.02) and osteoporosis (hazard ratio: 1.62; CI: 1.02-2.57; P < 0.04). CONCLUSION: patients with dementia frequently receive PIPs, and those who do are more likely to experience AHO. These results highlight the need to optimise medication in dementia patients, especially those with comorbidities.


Assuntos
Demência , Prescrição Inadequada , Idoso , Idoso de 80 Anos ou mais , Demência/diagnóstico , Demência/tratamento farmacológico , Demência/epidemiologia , Inglaterra/epidemiologia , Humanos , Incidência , Multimorbidade , Avaliação de Resultados em Cuidados de Saúde , Lista de Medicamentos Potencialmente Inapropriados , Estudos Retrospectivos
5.
J Immunol ; 201(10): 2934-2946, 2018 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-30315140

RESUMO

IL-6 is a critical driver of acute and chronic inflammation and has been reported to act as a T cell survival factor. The influence of IL-6 on T cell homeostasis is not well resolved. We demonstrate that IL-6 signaling drives T cell expansion under inflammatory conditions but not during normal homeostasis. During inflammation, IL-6Rα-deficient T cells are unable to effectively compete with wild type T cells. IL-6 promotes T cell proliferation, and this is associated with low-level expression of the RORγt transcription factor. T cells upregulate Rorc mRNA at levels substantially diminished from that seen in Th17 cells. Blockade of RORγt through genetic knockout or a small molecule inhibitor leads to T cell expansion defects comparable to those in IL-6Rα-deficient T cells. Our results indicate that IL-6 plays a key role in T cell expansion during inflammation and implicates a role for the transient induction of low-level RORγt.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Diferenciação Celular/imunologia , Interleucina-6/imunologia , Ativação Linfocitária/imunologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Animais , Linfócitos T CD4-Positivos/citologia , Proliferação de Células/fisiologia , Regulação da Expressão Gênica/imunologia , Homeostase/imunologia , Inflamação/imunologia , Camundongos , Camundongos Knockout , Linfócitos T/citologia , Linfócitos T/imunologia , Células Th17/citologia , Células Th17/imunologia
6.
Age Ageing ; 49(3): 374-381, 2020 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-32239180

RESUMO

IMPORTANCE: risk factors for delirium in hospital inpatients are well established, but less is known about whether delirium occurring in the community or during an emergency admission to hospital care might be predicted from routine primary-care records. OBJECTIVES: identify risk factors in primary-care electronic health records (PC-EHR) predictive of delirium occurring in the community or recorded in the initial episode in emergency hospitalisation. Test predictive performance against the cumulative frailty index. DESIGN: Stage 1: case-control; Stages 2 and 3: retrospective cohort. SETTING: clinical practice research datalink: PC-EHR linked to hospital discharge data from England. SUBJECTS: Stage 1: 17,286 patients with delirium aged ≥60 years plus 85,607 controls. Stages 2 and 3: patients ≥ 60 years (n = 429,548 in 2015), split into calibration and validation groups. METHODS: Stage 1: logistic regression to identify associations of 110 candidate risk measures with delirium. Stage 2: calibrating risk factor weights. Stage 3: validation in independent sample using area under the curve (AUC) receiver operating characteristic. RESULTS: fifty-five risk factors were predictive, in domains including: cognitive impairment or mental illness, psychoactive drugs, frailty, infection, hyponatraemia and anticholinergic drugs. The derived model predicted 1-year incident delirium (AUC = 0.867, 0.852:0.881) and mortality (AUC = 0.846, 0.842:0.853), outperforming the frailty index (AUC = 0.761, 0.740:0.782). Individuals with the highest 10% of predicted delirium risk accounted for 55% of incident delirium over 1 year. CONCLUSIONS: a risk factor model for delirium using data in PC-EHR performed well, identifying individuals at risk of new onsets of delirium. This model has potential for supporting preventive interventions.


Assuntos
Delírio , Registros Eletrônicos de Saúde , Delírio/diagnóstico , Delírio/epidemiologia , Inglaterra/epidemiologia , Hospitalização , Humanos , Estudos Retrospectivos , Fatores de Risco
7.
Hum Mol Genet ; 26(14): 2803-2811, 2017 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-28475762

RESUMO

Epigenetic regulation of immune cell types could be critical for the development and maintenance of autoimmune diseases like rheumatoid arthritis (RA). B cells are highly relevant in RA, since patients express autoantibodies and depleting this cell type is a successful therapeutic approach. Epigenetic variation, such as DNA methylation, may mediate the pathogenic activity of B cells. In this study, we performed an epigenome-wide association study (EWAS) for RA with three different replication cohorts, to identify disease-specific alterations in DNA methylation in B cells. CpG methylation in isolated B lymphocytes was assayed on the Illumina HumanMethylation450 BeadChip in a discovery cohort of RA patients (N = 50) and controls (N = 75). Differential methylation was observed in 64 CpG sites (q < 0.05). Six biological pathways were also differentially methylated in RA B cells. Analysis in an independent cohort of patients (N = 15) and controls (N = 15) validated the association of 10 CpG sites located on 8 genes CD1C, TNFSF10, PARVG, NID1, DHRS12, ITPK1, ACSF3 and TNFRSF13C, and 2 intergenic regions. Differential methylation at the CBL signaling pathway was replicated. Using an additional case-control cohort (N = 24), the association between RA risk and CpGs cg18972751 at CD1C (P = 2.26 × 10-9) and cg03055671 at TNFSF10 (P = 1.67 × 10-8) genes was further validated. Differential methylation at genes CD1C, TNFSF10, PARVG, NID1, DHRS12, ITPK1, ACSF3, TNFRSF13C and intergenic region chr10p12.31 was replicated in a cohort of systemic lupus erythematosus (SLE) patients (N = 47) and controls (N = 56). Our results highlight genes that may drive the pathogenic activity of B cells in RA and suggest shared methylation patterns with SLE.


Assuntos
Artrite Reumatoide/genética , Linfócitos B/metabolismo , Idoso , Artrite Reumatoide/metabolismo , Estudos de Casos e Controles , Estudos de Coortes , Ilhas de CpG/genética , Metilação de DNA/genética , Epigênese Genética/genética , Epigenômica/métodos , Feminino , Estudo de Associação Genômica Ampla/métodos , Humanos , Lúpus Eritematoso Sistêmico/genética , Masculino , Pessoa de Meia-Idade , Transdução de Sinais
8.
J Immunol ; 196(7): 2973-85, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26912317

RESUMO

How a large number of cytokines differentially signal through a small number of signal transduction pathways is not well resolved. This is particularly true for IL-6 and IL-10, which act primarily through STAT3 yet induce dissimilar transcriptional programs leading alternatively to pro- and anti-inflammatory effects. Kinetic differences in signaling, sustained to IL-10 and transient to IL-6, are critical to this in macrophages. T cells are also key targets of IL-6 and IL-10, yet how differential signaling in these cells leads to divergent cellular fates is unclear. We show that, unlike for macrophages, signal duration cannot explain the distinct effects of these cytokines in T cells. Rather, naive, activated, activated-rested, and memory CD4(+) T cells differentially express IL-6 and IL-10 receptors in an activation state-dependent manner, and this impacts downstream cytokine effects. We show a dominant role for STAT3 in IL-6-mediated Th17 subset maturation. IL-10 cannot support Th17 differentiation because of insufficient cytokine receptivity rather than signal quality. Enforced expression of IL-10Rα on naive T cells permits an IL-10-generated STAT3 signal equivalent to that of IL-6 and equally capable of promoting Th17 formation. Similarly, naive T cell IL-10Rα expression also allows IL-10 to mimic the effects of IL-6 on both Th1/Th2 skewing and Tfh cell differentiation. Our results demonstrate a key role for the regulation of receptor expression rather than signal quality or duration in differentiating the functional outcomes of IL-6 and IL-10 signaling, and identify distinct signaling properties of these cytokines in T cells compared with myeloid cells.


Assuntos
Diferenciação Celular , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Transdução de Sinais , Células Th17/citologia , Células Th17/metabolismo , Animais , Expressão Gênica , Imunofenotipagem , Interleucina-10/farmacologia , Subunidade alfa de Receptor de Interleucina-10/genética , Subunidade alfa de Receptor de Interleucina-10/metabolismo , Interleucina-6/farmacologia , Subunidade alfa de Receptor de Interleucina-6/genética , Subunidade alfa de Receptor de Interleucina-6/metabolismo , Camundongos , Camundongos Transgênicos , Fenótipo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Subpopulações de Linfócitos T/citologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Células Th1/citologia , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th1/metabolismo , Células Th17/efeitos dos fármacos , Células Th17/imunologia , Células Th2/citologia , Células Th2/efeitos dos fármacos , Células Th2/imunologia , Células Th2/metabolismo
9.
J Immunol ; 196(12): 4905-14, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27183575

RESUMO

How the TCR repertoire, in concert with risk-associated MHC, imposes susceptibility for autoimmune diseases is incompletely resolved. Due largely to recombinatorial biases, a small fraction of TCRα or ß-chains are shared by most individuals, or public. If public TCR chains modulate a TCRαß heterodimer's likelihood of productively engaging autoantigen, because they are pervasive and often high frequency, they could also broadly influence disease risk and progression. Prior data, using low-resolution techniques, have identified the heavy use of select public TCR in some autoimmune models. In this study, we assess public repertoire representation in mice with experimental autoimmune encephalomyelitis at high resolution. Saturation sequencing was used to identify >18 × 10(6) TCRß sequences from the CNSs, periphery, and thymi of mice at different stages of autoimmune encephalomyelitis and healthy controls. Analyses indicated the prominent representation of a highly diverse public TCRß repertoire in the disease response. Preferential formation of public TCR implicated in autoimmunity was identified in preselection thymocytes, and, consistently, public, disease-associated TCRß were observed to be commonly oligoclonal. Increased TCR sharing and a focusing of the public TCR response was seen with disease progression. Critically, comparisons of peripheral and CNS repertoires and repertoires from preimmune and diseased mice demonstrated that public TCR were preferentially deployed relative to nonshared, or private, sequences. Our findings implicate public TCR in skewing repertoire response during autoimmunity and suggest that subsets of public TCR sequences may serve as disease-specific biomarkers or influence disease susceptibility or progression.


Assuntos
Encefalomielite Autoimune Experimental/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Timo/imunologia , Sequência de Aminoácidos , Animais , Linfócitos T CD8-Positivos , Sistema Nervoso Central/citologia , Sistema Nervoso Central/imunologia , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Bainha de Mielina/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Timócitos/imunologia , Timo/ultraestrutura
10.
Psychooncology ; 26(1): 44-52, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-26486371

RESUMO

OBJECTIVE: In a sample of 368 postmenopausal women, we (1) determined within-cohort and between-cohort relationships between adjuvant systemic therapy for breast cancer and self-reported cognitive function during the first 18 months of therapy and (2) evaluated the influence of co-occurring symptoms, neuropsychological function, and other covariates on relationships. METHODS: We evaluated self-reported cognitive function, using the Patient Assessment of Own Functioning Inventory (PAOFI), and potential covariates (e.g., co-occurring symptom scores and neuropsychological function z-scores) in 158 women receiving aromatase inhibitor (AI) therapy alone, 104 women receiving chemotherapy followed by AI therapy, and 106 non-cancer controls. Patients were assessed before systemic therapy and then every 6 months, for a total of four assessments over 18 months. Controls were assessed at matched time points. Mixed-effects modeling was used to determine longitudinal relationships. RESULTS: Controlling for covariates, patients enrolled before chemotherapy reported poorer global cognitive function (p < 0.001), memory (p < 0.001), language and communication (p < 0.001), and sensorimotor function (p = 0.002) after chemotherapy. These patients reported poorer higher-level cognitive and intellectual functions from before chemotherapy to 12 months after initiation of AI therapy (p < 0.001). Higher levels of depressive symptoms (p < 0.001), anxiety (p < 0.001), and fatigue (p = 0.040) at enrollment were predictors of poorer cognitive function over time. PAOFI total score was a predictor of executive function (p = 0.048) and visual working memory (p = 0.005) z-scores, controlling for covariates. CONCLUSIONS: Findings provide further evidence of poorer self-reported cognitive function after chemotherapy and of relationships between co-occurring symptoms and cognitive changes. AI therapy alone does not have an impact on self-reported cognitive function. Copyright © 2015 John Wiley & Sons, Ltd.


Assuntos
Neoplasias da Mama/psicologia , Cognição , Pós-Menopausa/psicologia , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/terapia , Quimioterapia Adjuvante/efeitos adversos , Transtornos Cognitivos/etiologia , Estudos de Coortes , Terapia Combinada , Fadiga/etiologia , Feminino , Humanos , Memória , Pessoa de Meia-Idade , Autorrelato
11.
Circulation ; 130(7): 565-72, 2014 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-24920721

RESUMO

BACKGROUND: Genetic research regarding blood lipids has largely focused on DNA sequence variation; few studies have explored epigenetic effects. Genome-wide surveys of DNA methylation may uncover epigenetic factors influencing lipid metabolism. METHODS AND RESULTS: To identify whether differential methylation of cytosine-(phosphate)-guanine dinucleotides (CpGs) correlated with lipid phenotypes, we isolated DNA from CD4+ T cells and quantified the proportion of sample methylation at >450 000 CpGs by using the Illumina Infinium HumanMethylation450 Beadchip in 991 participants of the Genetics of Lipid Lowering Drugs and Diet Network. We modeled the percentage of methylation at individual CpGs as a function of fasting very-low-density lipoprotein cholesterol and triglycerides (TGs) by using mixed linear regression adjusted for age, sex, study site, cell purity, and family structure. Four CpGs (cg00574958, cg17058475, cg01082498, and cg09737197) in intron 1 of carnitine palmitoyltransferase 1A (CPT1A) were strongly associated with very-low low-density lipoprotein cholesterol (P=1.8×10(-21) to 1.6×10(-8)) and TG (P=1.6×10(-26) to 1.5×10(-9)). Array findings were validated by bisulfite sequencing. We performed quantitative polymerase chain reaction experiments demonstrating that methylation of the top CpG (cg00574958) was correlated with CPT1A expression. The association of cg00574958 with TG and CPT1A expression were replicated in the Framingham Heart Study (P=4.1×10(-14) and 3.1×10(-13), respectively). DNA methylation at CPT1A cg00574958 explained 11.6% and 5.5% of the variation in TG in the discovery and replication cohorts, respectively. CONCLUSIONS: This genome-wide epigenomic study identified CPT1A methylation as strongly and robustly associated with fasting very-low low-density lipoprotein cholesterol and TG. Identifying novel epigenetic contributions to lipid traits may inform future efforts to identify new treatment targets and biomarkers of disease risk.


Assuntos
Carnitina O-Palmitoiltransferase/genética , Epigenômica/métodos , Jejum , Estudo de Associação Genômica Ampla/métodos , Lipoproteínas VLDL/genética , Triglicerídeos/genética , Adulto , Anticolesterolemiantes/farmacologia , Anticolesterolemiantes/uso terapêutico , Carnitina O-Palmitoiltransferase/sangue , Estudos de Coortes , Jejum/sangue , Feminino , Humanos , Lipoproteínas VLDL/sangue , Masculino , Pessoa de Meia-Idade , Triglicerídeos/sangue
12.
Virol J ; 10: 120, 2013 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-23594747

RESUMO

BACKGROUND: Lymphocyte Function-Associated Antigen-1 (LFA-1) likely plays a role in the pathogenesis of against HIV-1 and is known to facilitate cell-to-cell transmission of the virus. A monoclonal antibody specific for LFA-1 (Cytolin®) was evaluated as a potential therapeutic in pilot studies performed in the mid-1990s. These uncontrolled human studies suggested that administration of this anti-LFA-1 antibody to HIV-1 infected individuals could provide a modest benefit by decreasing circulating HIV-1 RNA and increasing CD4+ T cell counts. At the time, it was proposed that when bound to cytolytic T cells, the antibody inhibited lysis of activated CD4+ T cells. Given the renewed interest in monoclonal antibody therapy for HIV-1 infected individuals, we investigated possible mechanisms of action of this antibody in vitro. METHODS: To assess whether this anti-LFA-1 antibody binds to HIV-1, a virus capture assay was performed. Binding of the antibody to cells was assessed using flow cytometry. Inhibition of HIV-1 replication was determined in culture by measuring the amount of p24 produced by ELISA. After co-culture of the antibody with peripheral blood mononuclear cells, supernatants were assayed for cytokines and chemokines using various immunoassays. RESULTS: Our experiments demonstrate that anti-LFA-1 antibody binds to CCR5 and CXCR4 utilizing strains of HIV-1. It also binds to CD8+ T cells and dendritic cells. When bound to virus prior to infection, there is no decrease in HIV-1 replication, suggesting it does not directly inhibit viral replication via virus binding. When bound to cells, it does not inhibit lysis of CD4+ T cells, as was originally hypothesized. Binding to cells does appear to induce the production of a soluble factor that inhibits HIV-1 replication. We determined that this soluble factor was not any of the cytokines or chemokines with known anti-HIV-1 activity. Further, the antibody does not appear to induce any common immune modulating cytokines or chemokines. CONCLUSIONS: These results suggest that one possible mechanism of action of this anti-LFA-1 antibody is to inhibit HIV-1 replication via the production of a soluble antiviral factor that is induced upon binding to cells.


Assuntos
Anticorpos Monoclonais/metabolismo , Antivirais/metabolismo , HIV-1/fisiologia , Antígeno-1 Associado à Função Linfocitária/metabolismo , Replicação Viral , Adulto , Anticorpos Monoclonais/imunologia , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Proteína do Núcleo p24 do HIV/biossíntese , Humanos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/virologia , Antígeno-1 Associado à Função Linfocitária/imunologia , Masculino , Ligação Proteica , Ligação Viral
13.
Bioorg Med Chem Lett ; 23(9): 2801-7, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23540644

RESUMO

Cathepsin L is a cysteine protease that is upregulated in a variety of malignant tumors and plays a significant role in cancer cell invasion and migration. It is an attractive target for the development of small-molecule inhibitors, which may prove beneficial as treatment agents to limit or arrest cancer metastasis. We have previously identified a structurally diverse series of thiosemicarbazone-based inhibitors that incorporate the benzophenone and thiochromanone molecular scaffolds. Herein we report an important extension of this work designed to explore fused aryl-alkyl ring molecular systems that feature nitrogen atom incorporation (dihydroquinoline-based) and carbon atom exclusivity (tetrahydronaphthalene-based). In addition, analogues that contain oxygen (chromanone-based), sulfur (thiochroman-based), sulfoxide, and sulfone functionalization have been prepared in order to further investigate the structure-activity relationship aspects associated with these compounds and their ability to inhibit cathepsins L and B. From this small-library of 30 compounds, five were found to be strongly inhibitory (IC50 <500 nM) against cathepsin L with the most active compound (7-bromodihydroquinoline thiosemicarbazone 48) demonstrating an IC50=164 nM. All of the compounds evaluated were inactive (IC50 >10,000 nM) as inhibitors of cathepsin B, thus establishing a high degree (>20-fold) of selectivity (cathepsin L vs. cathepsin B) for the most active cathepsin L inhibitors in this series.


Assuntos
Catepsina L/antagonistas & inibidores , Inibidores de Proteases/química , Bibliotecas de Moléculas Pequenas/química , Catepsina B/antagonistas & inibidores , Catepsina B/metabolismo , Catepsina L/metabolismo , Cromanos/química , Inibidores de Proteases/síntese química , Inibidores de Proteases/metabolismo , Ligação Proteica , Quinolinas/química , Safrol/análogos & derivados , Safrol/química , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/metabolismo , Relação Estrutura-Atividade , Sulfonas/química , Tetra-Hidronaftalenos/química
15.
Nat Struct Mol Biol ; 14(2): 169-71, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17220897

RESUMO

'Superantigens' (SAgs) trigger the massive activation of T cells by simultaneous interactions with MHC and TCR receptors, leading to human diseases. Here we present the first crystal structure, at 2.5-A resolution, of a complete ternary complex between a SAg and its two receptors, HLA-DR1/HA and TCR. The most striking finding is that the SAg Mycoplasma arthritidis mitogen, unlike others, has direct contacts not only with TCR Vbeta but with TCR Valpha.


Assuntos
Antígeno HLA-DR1/química , Hemaglutininas/química , Mitógenos/química , Proteínas/química , Receptores de Antígenos de Linfócitos T alfa-beta/química , Superantígenos/química , Sequência de Aminoácidos , Animais , Antígenos de Bactérias , Cristalografia por Raios X , Humanos , Camundongos , Modelos Moleculares , Dados de Sequência Molecular , Mycoplasma arthritidis/imunologia , Peptídeos/química
16.
Curr Microbiol ; 62(4): 1139-46, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21153729

RESUMO

Antimicrobial agent usage is common in animal agriculture for therapeutic and prophylactic purposes. Selective pressure exerted by these antimicrobials on soil bacteria could result in the selection of strains that are resistant due to chromosomal- or plasmid-derived genetic components. Multiple antimicrobial resistances in Escherichia coli and the direct relationship between antimicrobial agent use over time has been extensively studied, yet the relationship between the age of an animal agriculture environment such as a dairy farm and antibiotic resistance remains unclear. Therefore, we tested the hypothesis that antimicrobial-resistance profiles of E. coli isolated from dairy farm topsoil correlate with dairy farm age. E. coli isolated from eleven dairy farms of varying ages within Roosevelt County, NM were used for MIC determinations to chloramphenicol, nalidixic acid, penicillin, tetracycline, ampicillin, amoxicillin/clavulanic acid, gentamicin, trimethoprim/sulfamethoxazole, cefotaxime, and ciprofloxacin. The minimum inhibitory concentration values of four antibiotics ranged 0.75 to >256 µg/ml, 1 to >256 µg/ml, 12 to >256 µg/ml, and 0.75 to >256 µg/ml for chloramphenicol, nalidixic acid, penicillin, and tetracycline, respectively. The study did not show a direct relationship between antibiotic resistance and the age of dairy farms.


Assuntos
Antibacterianos/farmacologia , Indústria de Laticínios , Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Microbiologia do Solo , Escherichia coli/genética , Escherichia coli/isolamento & purificação , New Mexico
17.
J Am Geriatr Soc ; 69(2): 365-372, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33017050

RESUMO

BACKGROUND/OBJECTIVES: Delirium is common in older adults, especially following hospitalization. Because low vitamin D levels may be associated with increased delirium risk, we aimed to determine the prognostic value of blood vitamin D levels, extending our previous genetic analyses of this relationship. DESIGN: Prospective cohort analysis. SETTING: Community-based cohort study of adults from 22 cities across the United Kingdom (the UK Biobank). PARTICIPANTS: Adults aged 60 and older by the end of follow-up in the linked hospital inpatient admissions data, up to 14 years after baseline (n = 351,320). MEASUREMENTS: At baseline, serum vitamin D (25-OH-D) levels were measured. We used time-to-event models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between vitamin D deficiency and incident hospital-diagnosed delirium, adjusted for age, sex, assessment month, assessment center, and ethnicity. We performed Mendelian randomization genetic analysis in European participants to further investigate vitamin D and delirium risk. RESULTS: A total of 3,634 (1.03%) participants had at least one incident hospital-diagnosed delirium episode. Vitamin D deficiency (<25 nmol/L) predicted a large incidence in delirium (HR = 2.49; 95% CI = 2.24-2.76; P = 3*10-68 , compared with >50 nmol/L). Increased risk was not limited to the deficient group: insufficient levels (25-50 nmol/L) were also at increased risk (HR = 1.38; 95% CI = 1.28-1.49; P = 4*10-18 ). The association was independent of calcium levels, hospital-diagnosed fractures, dementia, and other relevant cofactors. In genetic analysis, participants carrying more vitamin D-increasing variants had a reduced likelihood of incident delirium diagnosis (HR = .80 per standard deviation increase in genetically instrumented vitamin D: .73-.87; P = 2*10-7 ). CONCLUSION: Progressively lower vitamin D levels predicted increased risks of incident hospital-diagnosed delirium, and genetic evidence supports a shared causal pathway. Because low vitamin D levels are simple to detect and inexpensive and safe to correct, an intervention trial to confirm these results is urgently needed.


Assuntos
Delírio , Hospitalização/estatística & dados numéricos , Deficiência de Vitamina D , Vitamina D/sangue , Idoso , Bancos de Espécimes Biológicos , Causalidade , Estudos de Coortes , Delírio/sangue , Delírio/epidemiologia , Delírio/fisiopatologia , Feminino , Avaliação Geriátrica/métodos , Humanos , Incidência , Masculino , Análise da Randomização Mendeliana , Valor Preditivo dos Testes , Medição de Risco/métodos , Fatores de Risco , Reino Unido/epidemiologia , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/epidemiologia , Deficiência de Vitamina D/psicologia
18.
J Immunol ; 181(9): 6255-64, 2008 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-18941216

RESUMO

T cells are known to cross-react with diverse peptide MHC Ags through their alphabeta TCR. To explore the basis of such cross-reactivity, we examined the 2C TCR that recognizes two structurally distinct ligands, SIY-K(b) and alloantigen QL9-L(d). In this study we characterized the cross-reactivity of several high-affinity 2C TCR variants that contained mutations only in the CDR3alpha loop. Two of the TCR lost their ability to cross-react with the reciprocal ligand (SIY-K(b)), whereas another TCR (m67) maintained reactivity with both ligands. Crystal structures of four of the TCRs in complex with QL9-L(d) showed that CDR1, CDR2, and CDR3beta conformations and docking orientations were remarkably similar. Although the CDR3alpha loop of TCR m67 conferred a 2000-fold higher affinity for SIY-K(b), the TCR maintained the same docking angle on QL9-L(d) as the 2C TCR. Thus, CDR3alpha dictated the affinity and level of cross-reactivity, yet it did so without affecting the conserved docking orientation.


Assuntos
Regiões Determinantes de Complementaridade/química , Antígenos H-2/metabolismo , Oligopeptídeos/metabolismo , Receptores de Antígenos de Linfócitos T alfa-beta/química , Sequência de Aminoácidos , Animais , Regiões Determinantes de Complementaridade/genética , Regiões Determinantes de Complementaridade/metabolismo , Sequência Conservada , Reações Cruzadas/genética , Reações Cruzadas/imunologia , Antígenos H-2/química , Antígenos H-2/genética , Antígeno de Histocompatibilidade H-2D , Complexo Cetoglutarato Desidrogenase/genética , Complexo Cetoglutarato Desidrogenase/imunologia , Complexo Cetoglutarato Desidrogenase/metabolismo , Camundongos , Dados de Sequência Molecular , Oligopeptídeos/química , Oligopeptídeos/genética , Oligopeptídeos/imunologia , Ligação Proteica/genética , Ligação Proteica/imunologia , Transporte Proteico/genética , Transporte Proteico/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo
19.
J Nurses Prof Dev ; 35(5): 248-254, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31425310

RESUMO

Effective communication in health care is a mainstay of patient safety and staff perception of a healthy work environment. A quasi-experimental study was conducted to assess the impact of a course on staff perceptions of communication. A Wilcoxon signed-ranks test indicated a statistically significant difference between pre and post scores for the self-assessment component of the Heathy Work Environment Instrument (p = .0005); coworker assessments revealed borderline statistical significance (p = .056).


Assuntos
Comunicação , Currículo , Recursos Humanos de Enfermagem/educação , Local de Trabalho/psicologia , Avaliação Educacional , Humanos , Recursos Humanos de Enfermagem/psicologia , Segurança do Paciente , Autoavaliação (Psicologia) , Inquéritos e Questionários
20.
Neurology ; 92(12): e1387-e1394, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30770424

RESUMO

OBJECTIVE: To estimate effects of vitamin D levels on incident delirium hospital admissions using inherited genetic variants in mendelian randomization models, which minimize confounding and exclude reverse causation. METHODS: Longitudinal analysis using the UK Biobank, community-based, volunteer cohort (2006-2010) with incident hospital-diagnosed delirium (ICD-10 F05) ascertained during ≤9.9 years of follow-up of hospitalization records (to early 2016). We included volunteers of European descent aged 60-plus years by end of follow-up. We used single-nucleotide polymorphisms previously shown to increase circulating vitamin D levels, and APOE variants. Cox competing models accounting for mortality were used. RESULTS: Of 313,121 participants included, 544 were hospitalized with delirium during follow-up. Vitamin D variants were protective for incident delirium: hazard ratio = 0.74 per 10 nmol/L (95% confidence interval 0.62-0.87, p = 0.0004) increase in genetically instrumented vitamin D, with no evidence for pleiotropy (mendelian randomization-Egger p > 0.05). Participants with ≥1 APOE ε4 allele were more likely to develop delirium (e.g., ε4ε4 hazard ratio = 3.73, 95% confidence interval 2.68-5.21, p = 8.0 × 10-15 compared to ε3ε3), but there was no interaction with vitamin D variants. CONCLUSIONS AND RELEVANCE: In a large community-based cohort, there is genetic evidence supporting a causal role for vitamin D levels in incident delirium. Trials of correction of low vitamin D levels in the prevention of delirium are needed.


Assuntos
Delírio/epidemiologia , Delírio/genética , Vitamina D/genética , Adulto , Idoso , Apolipoproteínas E/genética , Bancos de Espécimes Biológicos , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Análise da Randomização Mendeliana , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Reino Unido , População Branca/genética
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