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1.
Cancer Immunol Immunother ; 72(1): 55-71, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35708739

RESUMO

Tumour acidosis contributes to cancer progression by inhibiting anti-tumour immunity. However, the effect of acidosis on anti-tumour T cell phenotypes in oesophageal adenocarcinoma (OAC) is unknown. Therefore, this study investigated the effect of acidosis on anti-tumour T cell profiles and if immune checkpoint blockade (ICB) could enhance anti-tumour T cell immunity under acidosis. Acidic conditions substantially altered immune checkpoint expression profiles of OAC patient-derived T cells, upregulating TIM-3, LAG-3 and CTLA-4. Severe acidosis (pH 5.5) significantly decreased the percentage of central memory CD4+ T cells, an effect that was attenuated by ICB treatment. ICB increased T cell production of IFN-γ under moderate acidosis (pH 6.6) but not severe acidosis (pH 5.5) and decreased IL-10 production by T cells under severe acidic conditions only. A link between lactate and metastasis was also depicted; patients with nodal metastasis had higher serum lactate levels (p = 0.07) which also positively correlated with circulating levels of pro-angiogenic factor Tie-2. Our findings establish that acidosis-induced upregulation of immune checkpoints on T cells may potentially contribute to immune evasion and disease progression in OAC. However, acidic conditions curtailed ICB efficacy, supporting a rationale for utilizing systemic oral buffers to neutralize tumour acidity to improve ICB efficacy. Study schematic-PBMCs were isolated from OAC patients (A) and expanded ex vivo for 7 days using anti-CD3/28 +IL-2 T cell activation protocol (B) and further cultured for 48 h under increasing acidic conditions in the absence or presence of immune checkpoint blockade (nivolumab, ipilimumab or dual nivolumab + ipilimumab) (C). Immunophenotyping was then carried out to assess immune checkpoint expression profiles and anti-tumour T cell phenotypes (D). Serum lactate was assessed in OAC patients (E-F) and levels were correlated with patient demographics (G) and the levels of circulating immune/pro-angiogenic cytokines that were determined by multiplex ELISA (H). Key Findings-severe acidic conditions upregulated multiple immune checkpoints on T cells (I). Efficacy of ICB was curtailed under severe acidic conditions (J). Circulating lactate levels positively correlated with circulating levels of pro-angiogenic factor tie-2 and higher serum lactate levels were found in patients who had nodal metastasis (K).


Assuntos
Adenocarcinoma , Linfócitos T , Humanos , Linfócitos T/metabolismo , Ipilimumab/uso terapêutico , Nivolumabe/uso terapêutico , Inibidores de Checkpoint Imunológico/uso terapêutico , Indutores da Angiogênese/uso terapêutico , Adenocarcinoma/patologia
2.
Prev Sci ; 24(5): 887-900, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37507627

RESUMO

Older adult drinking poses a growing public health concern, especially given the ongoing aging of the United States population. As part of a larger lifespan developmental project contrasting predictors of drinking reductions across different periods of adulthood, we tested age differences in effects of health problems on drinking declines across young adulthood, midlife, and older adulthood. We predicted these effects to be developmentally specific to midlife and older adulthood. We also tested moderation by alcohol use disorder (AUD) symptomatology and by indices of sociodemographic disadvantage (sex and race/ethnicity). Analyses used data from the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC), leveraging NESARC's vast age range (18-90 + ; N = 43,093) and two waves of longitudinal data. Multiple-group cross-lag models tested differences across age groups in cross-lag paths between health problems and alcohol consumption. As hypothesized, health problem effects on drinking reductions were developmentally specific to midlife and older adulthood. However, models testing moderation by AUD symptomatology showed that these adaptive effects of health problems on drinking reductions did not extend to those with one or more AUD symptoms. Little evidence was found for moderation by sex or race/ethnicity. Findings support the notion of health concerns as a pathway to drinking reduction that increases in importance across the adult lifespan. However, given the moderation by AUD symptoms, findings also highlight a need to understand barriers to health-related pathways to drinking reduction among relatively severe midlife and older adult drinkers. These findings hold implications for lifespan developmental tailoring of clinical, public health, and policy interventions.


Assuntos
Transtornos Relacionados ao Uso de Álcool , Alcoolismo , Humanos , Estados Unidos/epidemiologia , Idoso , Adulto Jovem , Adulto , Longevidade , Consumo de Bebidas Alcoólicas/epidemiologia , Alcoolismo/epidemiologia , Transtornos Relacionados ao Uso de Álcool/diagnóstico , Transtornos Relacionados ao Uso de Álcool/epidemiologia , Estudos Longitudinais
3.
J Neuroinflammation ; 18(1): 139, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34130712

RESUMO

BACKGROUND: Burgeoning evidence highlights seminal roles for microglia in the pathogenesis of neurodegenerative diseases including amyotrophic lateral sclerosis (ALS). The receptor for advanced glycation end products (RAGE) binds ligands relevant to ALS that accumulate in the diseased spinal cord and RAGE has been previously implicated in the progression of ALS pathology. METHODS: We generated a novel mouse model to temporally delete Ager from microglia in the murine SOD1G93A model of ALS. Microglia Ager deficient SOD1G93A mice and controls were examined for changes in survival, motor function, gliosis, motor neuron numbers, and transcriptomic analyses of lumbar spinal cord. Furthermore, we examined bulk-RNA-sequencing transcriptomic analyses of human ALS cervical spinal cord. RESULTS: Transcriptomic analysis of human cervical spinal cord reveals a range of AGER expression in ALS patients, which was negatively correlated with age at disease onset and death or tracheostomy. The degree of AGER expression related to differential expression of pathways involved in extracellular matrix, lipid metabolism, and intercellular communication. Microglia display increased RAGE immunoreactivity in the spinal cords of high AGER expressing patients and in the SOD1G93A murine model of ALS vs. respective controls. We demonstrate that microglia Ager deletion at the age of symptomatic onset, day 90, in SOD1G93A mice extends survival in male but not female mice. Critically, many of the pathways identified in human ALS patients that accompanied increased AGER expression were significantly ameliorated by microglia Ager deletion in male SOD1G93A mice. CONCLUSIONS: Our results indicate that microglia RAGE disrupts communications with cell types including astrocytes and neurons, intercellular communication pathways that divert microglia from a homeostatic to an inflammatory and tissue-injurious program. In totality, microglia RAGE contributes to the progression of SOD1G93A murine pathology in male mice and may be relevant in human disease.


Assuntos
Esclerose Lateral Amiotrófica/patologia , Microglia/metabolismo , Microglia/patologia , Neurônios Motores/patologia , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Caracteres Sexuais , Superóxido Dismutase-1/genética , Animais , Astrócitos/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Feminino , Gliose/patologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Receptor para Produtos Finais de Glicação Avançada/genética , Análise de Sequência de RNA , Medula Espinal/patologia , Superóxido Dismutase-1/metabolismo
4.
J Am Chem Soc ; 142(12): 5509-5514, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32148033

RESUMO

Graphene nanoribbons (GNRs), narrow and straight-edged stripes of graphene, attract a great deal of attention because of their excellent electronic and magnetic properties. As of yet, there is no fabrication method for GNRs to satisfy both precision at the atomic scale and scalability, which is critical for fundamental research and future technological development. Here, we report a methodology for bulk-scale synthesis of GNRs with atomic precision utilizing a metal-organic framework (MOF). The GNR was synthesized by the polymerization of perylene (PER) or its derivative within the nanochannels of the MOF. Molecular dynamics simulations showed that PER was uniaxially aligned along the nanochannels of the MOF through host-guest interactions, which allowed for regulated growth of the nanoribbons. A series of characterizations of the GNR, including NMR, UV/vis/NIR, and Raman spectroscopy measurements, confirmed the formation of the GNR with well-controlled edge structure and width.

6.
J Biol Chem ; 292(40): 16594-16604, 2017 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-28821608

RESUMO

The function of protein products generated from intramembraneous cleavage by the γ-secretase complex is not well defined. The γ-secretase complex is responsible for the cleavage of several transmembrane proteins, most notably the amyloid precursor protein that results in Aß, a transmembrane (TM) peptide. Another protein that undergoes very similar γ-secretase cleavage is the p75 neurotrophin receptor. However, the fate of the cleaved p75 TM domain is unknown. p75 neurotrophin receptor is highly expressed during early neuronal development and regulates survival and process formation of neurons. Here, we report that the p75 TM can stimulate the phosphorylation of TrkB (tyrosine kinase receptor B). In vitro phosphorylation experiments indicated that a peptide representing p75 TM increases TrkB phosphorylation in a dose- and time-dependent manner. Moreover, mutagenesis analyses revealed that a valine residue at position 264 in the rat p75 neurotrophin receptor is necessary for the ability of p75 TM to induce TrkB phosphorylation. Because this residue is just before the γ-secretase cleavage site, we then investigated whether the p75(αγ) peptide, which is a product of both α- and γ-cleavage events, could also induce TrkB phosphorylation. Experiments using TM domains from other receptors, EGFR and FGFR1, failed to stimulate TrkB phosphorylation. Co-immunoprecipitation and biochemical fractionation data suggested that p75 TM stimulates TrkB phosphorylation at the cell membrane. Altogether, our results suggest that TrkB activation by p75(αγ) peptide may be enhanced in situations where the levels of the p75 receptor are increased, such as during brain injury, Alzheimer's disease, and epilepsy.


Assuntos
Membrana Celular/metabolismo , Glicoproteínas de Membrana/metabolismo , Receptor de Fator de Crescimento Neural/metabolismo , Receptor trkB/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Substituição de Aminoácidos , Animais , Lesões Encefálicas/genética , Lesões Encefálicas/metabolismo , Membrana Celular/genética , Epilepsia/genética , Epilepsia/metabolismo , Humanos , Glicoproteínas de Membrana/genética , Mutagênese , Mutação de Sentido Incorreto , Fosforilação , Domínios Proteicos , Ratos , Receptor de Fator de Crescimento Neural/genética , Receptor trkB/genética , Células Sf9 , Spodoptera
7.
J Am Chem Soc ; 140(5): 1576-1579, 2018 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-29211456

RESUMO

Highly stable gold nanoparticles (Au NPs) functionalized by bidentate N-heterocyclic carbene (NHC) ligands have been synthesized by top-down and bottom-up approaches. A detailed study of the effect of alkylation, denticity, and method of synthesis has led to the production of NHC-stabilized nanoparticles with higher thermal stability than bi- and tridentate thiol-protected Au NPs and than monodentate NHC-stabilized NPs. Importantly, bidentate NHC-protected NPs also displayed unprecedented stability to external thiol, which has been an unsolved problem to date with all nanoparticles. Thus, multidentate NHC ligands are an important, and as yet unrecognized, step forward for the preparation of high stability nanomaterials.

8.
J Gen Intern Med ; 33(6): 855-862, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29404948

RESUMO

BACKGROUND: Early detection of melanoma represents an opportunity to reduce the burden of disease among people at increased risk for melanoma. OBJECTIVE: To develop and demonstrate the efficacy of online training. DESIGN: Randomized educational trial. PARTICIPANTS: Primary care providers (PCPs). INTERVENTION: Mastery learning course with visual and dermoscopic assessment, diagnosis and management, and deliberate practice with feedback to reach a minimum passing standard. MAIN MEASURES: Pre-test/post-test diagnostic accuracy. Referral of concerning lesions for 3 months before and after the educational intervention. KEY RESULTS: Among the 89 PCPs, 89.8% were internal medicine physicians, and the remainder were physician assistants embedded in internists' practices. There were no differences between control and intervention groups regarding gender, age, race, or percentage of full-time PCPs. The control group had more PCPs who reported less than 5 years of practice (n = 18) than the intervention group (n = 6) (χ2 [6, n = 89] = 14.34, p = 0.03). PCPs in the intervention group answered more melanoma detection questions correctly on the post-test (M = 10.05, SE = 1.24) compared to control group PCPs (M = 7.11, SE = 0.24), and had fewer false-positive and no false-negative melanoma diagnoses (intervention, M = 1.09, SE = 0. 20; control, M = 3.1, SE = 0.23; ANCOVA, F[1,378] =27.86, p < 0.001; ηp2 = 0.26). PCPs who underwent training referred fewer benign lesions, including nevi, seborrheic keratoses, and dermatofibromas, than control PCPs (F[1,79] = 72.89, p < 0.001; ηp2 = 0.489; F[1,79] = 25.82, p < 0.001; ηp2 = 0.246; F[1,79] = 34.25, p < 0.001; ηp2 = 0.302; respectively). Those receiving training referred significantly more melanomas than controls (F[1,79] = 24.38, p < 0.001; ηp2 = 0.236). Referred melanomas (0.8 ± 0.07 per month for intervention, 0.17 ± 0.06 for control) were mostly located on the head and neck. CONCLUSIONS: Mastery learning improved PCPs' ability to detect melanoma on a standardized post-test and may improve referral of patients with suspected melanoma. Further studies are needed to confirm this finding. ClinicalTrials.gov NCT02385253.


Assuntos
Competência Clínica/normas , Detecção Precoce de Câncer/normas , Melanoma/diagnóstico , Assistentes Médicos/normas , Médicos de Atenção Primária/normas , Neoplasias Cutâneas/diagnóstico , Adulto , Detecção Precoce de Câncer/métodos , Feminino , Humanos , Aprendizagem , Masculino , Pessoa de Meia-Idade , Assistentes Médicos/educação , Médicos de Atenção Primária/educação
9.
Angew Chem Int Ed Engl ; 55(2): 708-13, 2016 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-26609906

RESUMO

Strong interchain interactions render unsubstituted polythiophene un-fusible, non-melting, and insoluble. Therefore, control of the packing structure, which has a profound effect on the optical and electronic properties of the polymer, has never been achieved. Unsubstituted polythiophene was prepared in the one-dimensional channels of [La(1,3,5-benzenetrisbenzoate)]n, where polymer chains form unprecedented assembly structures mediated by the host framework. It is noteworthy that the emission and carrier transport properties were drastically changed by varying the number of chains within a particular assembly. The response of the composite to additional guests is also examined as a method to use the composites as low-concentration sensors. Our findings show that the encapsulation of polymer chains in host materials is a facile method for understanding the intrinsic properties of conjugated polymers, along with controlling and enhancing their functions.

10.
bioRxiv ; 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38854045

RESUMO

Glaucoma is a neurodegenerative disease that leads to the death of retinal ganglion cells (RGCs). A growing body of literature suggests a role for neuroinflammation in RGC death after glaucoma-relevant insults. For instance, it was shown that deficiency of three proinflammatory cytokines, complement component 1, subcomponent q ( C1q ), interleukin 1 alpha ( Il1a ), and tumor necrosis factor ( Tnf ), resulted in near complete protection of RGCs after two glaucoma-relevant insults, optic nerve injury and ocular hypertension. While TNF and C1Q have been extensively investigated in glaucoma-relevant model systems, the role of IL1A in RGC is not as well defined. Thus, we investigated the direct neurotoxicity of IL1A on RGCs in vivo. Intravitreal injection of IL1A did not result in RGC death at either 14 days or 12 weeks after insult. Consistent with previous studies, TNF injection did not result in significant RGC loss at 14 days but did after 12 weeks. Interestingly, IL1A+TNF resulted in a relatively rapid RGC death, driving significant RGC loss two weeks after injection. JUN activation and SARM1 have been implicated in RGC death in glaucoma and after cytokine insult. Using mice deficient in JUN or SARM1, we show RGC loss after IL1A+TNF insult is JUN-independent and SARM1-dependent. Furthermore, RNA-seq analysis showed that RGC death by SARM1 deficiency does not stop the neuroinflammatory response to IL1A+TNF. These findings indicate that IL1A can potentiate TNF-induced RGC death after combined insult is likely driven by a SARM1-dependent RGC intrinsic signaling pathway.

11.
IEEE Trans Biomed Circuits Syst ; 18(2): 396-407, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37938943

RESUMO

Opioid-induced overdose is one of the leading causes of death among the US population under the age of 50. In 2021 alone, the death toll among opioid users rose to a devastating number of over 80,000. The overdose process can be reversed by the administration of naloxone, an opioid antagonist that rapidly counteracts the effects of opioid-induced respiratory depression. The idea of a closed-loop opioid overdose detection and naloxone delivery has emerged as a potential engineered solution to mitigate the deadly effects of the opioid epidemic. In this work, we introduce a wrist-worn wearable device that overcomes the portability issues of our previous work to create a closed-loop drug-delivery system, which includes (1) a Near-Infrared Spectroscopy (NIRS) sensor to detect a hypoxia-driven opioid overdose event, (2) a MOSFET switch, and (3) a Zero-Voltage Switching (ZVS) electromagnetic heater. Using brachial artery occlusion (BAO) with human subjects (n = 8), we demonstrated consistent low oxygenation events. Furthermore, we proved our device's capability to release the drug within 10 s after detecting a hypoxic event. We found that the changes in the oxyhemoglobin, deoxyhemoglobin and oxygenation saturation levels ( SpO2) were different before and after the low-oxygenation events ( 0.001). Although additional human experiments are needed, our results to date point towards a potential tool in the battle to mitigate the effects of the opioid epidemic.


Assuntos
Overdose de Drogas , Overdose de Opiáceos , Humanos , Analgésicos Opioides/uso terapêutico , Overdose de Opiáceos/tratamento farmacológico , Antagonistas de Entorpecentes/uso terapêutico , Naloxona/uso terapêutico , Overdose de Drogas/tratamento farmacológico
12.
bioRxiv ; 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38659747

RESUMO

Background: Age is the principal risk factor for neurodegeneration in both the retina and brain. The retina and brain share many biological properties; thus, insights into retinal aging and degeneration may shed light onto similar processes in the brain. Genetic makeup strongly influences susceptibility to age-related retinal disease. However, studies investigating retinal aging have not sufficiently accounted for genetic diversity. Therefore, examining molecular aging in the retina across different genetic backgrounds will enhance our understanding of human-relevant aging and degeneration in both the retina and brain-potentially improving therapeutic approaches to these debilitating conditions. Methods: Transcriptomics and proteomics were employed to elucidate retinal aging signatures in nine genetically diverse mouse strains (C57BL/6J, 129S1/SvlmJ, NZO/HlLtJ, WSB/EiJ, CAST/EiJ, PWK/PhK, NOD/ShiLtJ, A/J, and BALB/cJ) across lifespan. These data predicted human disease-relevant changes in WSB and NZO strains. Accordingly, B6, WSB and NZO mice were subjected to human-relevant in vivo examinations at 4, 8, 12, and/or 18M, including: slit lamp, fundus imaging, optical coherence tomography, fluorescein angiography, and pattern/full-field electroretinography. Retinal morphology, vascular structure, and cell counts were assessed ex vivo. Results: We identified common molecular aging signatures across the nine mouse strains, which included genes associated with photoreceptor function and immune activation. Genetic background strongly modulated these aging signatures. Analysis of cell type-specific marker genes predicted age-related loss of photoreceptors and retinal ganglion cells (RGCs) in WSB and NZO, respectively. Fundus exams revealed retinitis pigmentosa-relevant pigmentary abnormalities in WSB retinas and diabetic retinopathy (DR)-relevant cotton wool spots and exudates in NZO retinas. Profound photoreceptor dysfunction and loss were confirmed in WSB. Molecular analyses indicated changes in photoreceptor-specific proteins prior to loss, suggesting photoreceptor-intrinsic dysfunction in WSB. In addition, age-associated RGC dysfunction, loss, and concomitant microvascular dysfunction was observed in NZO mice. Proteomic analyses revealed an early reduction in protective antioxidant processes, which may underlie increased susceptibility to DR-relevant pathology in NZO. Conclusions: Genetic context is a strong determinant of retinal aging, and our multi-omics resource can aid in understanding age-related diseases of the eye and brain. Our investigations identified and validated WSB and NZO mice as improved preclinical models relevant to common retinal neurodegenerative diseases.

13.
bioRxiv ; 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38496398

RESUMO

In recent years, microglia have been highlighted for playing integral roles in neurodegenerative diseases, like glaucoma. To better understand the role of microglia during chronic ocular hypertension, we depleted microglia from aged (9-12 months old) DBA/2J (D2) mice, which exhibit age-related increases in intraocular pressure, using a dietary CSF1R antagonist, PLX5622. Retinal ganglion cell (RGC) somas were counted, and optic nerve cross-sections stained and assessed for glaucomatous damage. Sustained administration of dietary PLX5622 significantly reduced the numbers of retinal microglia. Dietary PLX5622 did not lead to changes in intraocular pressure in D2 or normotensive DBA/2J-Gpnmb+ (D2-Gpnmb+) control mice. While PLX5622-treated D2-Gpnmb+ did not develop optic nerve damage, PLX5622-treated D2 mice showed a significant increase in moderate-to-severe optic nerve damage compared to D2 mice fed a control diet. In conclusion, global reduction of microglia exacerbated glaucomatous neurodegeneration in D2 mice suggesting microglia play an overall beneficial role in protecting from ocular hypertension associated RGC loss.

14.
Alzheimers Dement (N Y) ; 10(1): e12458, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38469553

RESUMO

INTRODUCTION: In September 2022, The Jackson Laboratory Center for Alzheimer's and Dementia Research (JAX CADR) hosted a workshop with leading researchers in the Alzheimer's disease and related dementias (ADRD) field. METHODS: During the workshop, the participants brainstormed new directions to overcome current barriers to providing patients with effective ADRD therapeutics. The participants outlined specific areas of focus. Following the workshop, each group used standard literature search methods to provide background for each topic. RESULTS: The team of invited experts identified four key areas that can be collectively addressed to make a significant impact in the field: (1) Prioritize the diversification of disease targets, (2) enhance factors promoting resilience, (3) de-risk clinical pipeline, and (4) centralize data management. DISCUSSION: In this report, we review these four objectives and propose innovations to expedite ADRD therapeutic pipelines.

16.
J Cancer Res Clin Oncol ; 149(8): 5377-5395, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36445478

RESUMO

AIM: Use of immune checkpoint blockade to enhance T cell-mediated immunity within the hostile tumour microenvironment (TME) is an attractive approach in oesophageal adenocarcinoma (OAC). This study explored the effects of the hostile TME, including nutrient deprivation and hypoxia, on immune checkpoint (IC) expression and T cell phenotypes, and the potential use of nivolumab to enhance T cell function under such conditions. METHODS AND RESULTS: ICs were upregulated on stromal immune cells within the tumour including PD-L2, CTLA-4 and TIGIT. OAC patient-derived PBMCs co-cultured with OE33 OAC cells upregulated LAG-3 and downregulated the co-stimulatory marker CD27 on T cells, highlighting the direct immunosuppressive effects of tumour cells on T cells. Hypoxia and nutrient deprivation altered the secretome of OAC patient-derived PBMCs, which induced upregulation of PD-L1 and PD-L2 on OE33 OAC cells thus enhancing an immune-resistant phenotype. Importantly, culturing OAC patient-derived PBMCs under dual hypoxia and glucose deprivation, reflective of the conditions within the hostile TME, upregulated an array of ICs on the surface of T cells including PD-1, CTLA-4, A2aR, PD-L1 and PD-L2 and decreased expression of IFN-γ by T cells. Addition of nivolumab under these hostile conditions decreased the production of pro-tumorigenic cytokine IL-10. CONCLUSION: Collectively, these findings highlight the immunosuppressive crosstalk between tumour cells and T cells within the OAC TME. The ability of nivolumab to suppress pro-tumorigenic T cell phenotypes within the hostile TME supports a rationale for the use of immune checkpoint blockade to promote anti-tumour immunity in OAC. Study schematic: (A) IC expression profiles were assessed on CD45+ cells in peripheral whole blood and infiltrating tumour tissue from OAC patients in the treatment-naïve setting. (B) PBMCs were isolated from OAC patients and expanded ex vivo for 5 days using anti-CD3/28 + IL-2 T cell activation protocol and then co-cultured for 48 h with OE33 cells. T cell phenotypes were then assessed by flow cytometry. (C) PBMCs were isolated from OAC patients and expanded ex vivo for 5 days using anti-CD3/28 + IL-2 T cell activation protocol and then further cultured under conditions of nutrient deprivation or hypoxia for 48 h and T cell phenotypes were then assessed by flow cytometry. KEY FINDINGS: (A) TIGIT, CTLA-4 and PD-L2 were upregulated on CD45+ immune cells and CTLA-4 expression on CD45+ cells correlated with a subsequent decreased response to neoadjuvant regimen. (B) Following a 48 h co-culture with OE33 cells, T cells upregulated LAG-3 and decreased CD27 co-stimulatory marker. (C) Nutrient deprivation and hypoxia upregulated a range of ICs on T cells and decreased IFN-γ production by T cells. Nivolumab decreased IL-10 production by T cells under nutrient deprivation-hypoxic conditions.


Assuntos
Antígeno B7-H1 , Linfócitos T , Humanos , Antígeno CTLA-4 , Interleucina-10 , Nivolumabe , Inibidores de Checkpoint Imunológico , Interleucina-2 , Imunoterapia , Hipóxia , Microambiente Tumoral
17.
Commun Biol ; 5(1): 177, 2022 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-35228715

RESUMO

Amyotrophic lateral sclerosis (ALS) is an incurable disease characterized by proteinaceous aggregate accumulation and neuroinflammation culminating in rapidly progressive lower and upper motor neuron death. To interrogate cell-intrinsic and inter-cell type perturbations in ALS, single-nucleus RNA sequencing was performed on the lumbar spinal cord in the murine ALS model SOD1G93A transgenic and littermate control mice at peri-symptomatic onset stage of disease, age 90 days. This work uncovered perturbed tripartite synapse functions, complement activation and metabolic stress in the affected spinal cord; processes evidenced by cell death and proteolytic stress-associated gene sets. Concomitantly, these pro-damage events in the spinal cord co-existed with dysregulated reparative mechanisms. This work provides a resource of cell-specific niches in the ALS spinal cord and asserts that interwoven dysfunctional neuronal-glial communications mediating neurodegeneration are underway prior to overt disease manifestation and are recapitulated, in part, in the human post-mortem ALS spinal cord.


Assuntos
Esclerose Lateral Amiotrófica , Comunicação Celular , Neurônios Motores , Neuroglia , Medula Espinal , Superóxido Dismutase-1 , Animais , Comunicação Celular/fisiologia , Modelos Animais de Doenças , Camundongos , Neuroglia/citologia , Neuroglia/metabolismo , Medula Espinal/metabolismo , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo
18.
Immunometabolism ; 3(3)2021.
Artigo em Inglês | MEDLINE | ID: mdl-34178389

RESUMO

Fundamental modulation of energy metabolism in immune cells is increasingly being recognized for the ability to impart important changes in cellular properties. In homeostasis, cells of the innate immune system, such as monocytes, macrophages and dendritic cells (DCs), are enabled to respond rapidly to various forms of acute cellular and environmental stress, such as pathogens. In chronic stress milieus, these cells may undergo a re-programming, thereby triggering processes that may instigate tissue damage and failure of resolution. In settings of metabolic dysfunction, moieties such as excess sugars (glucose, fructose and sucrose) accumulate in the tissues and may form advanced glycation end products (AGEs), which are signaling ligands for the receptor for advanced glycation end products (RAGE). In addition, cellular accumulation of cholesterol species such as that occurring upon macrophage engulfment of dead/dying cells, presents these cells with a major challenge to metabolize/efflux excess cholesterol. RAGE contributes to reduced expression and activities of molecules mediating cholesterol efflux. This Review chronicles examples of the roles that sugars and cholesterol, via RAGE, play in immune cells in instigation of maladaptive cellular signaling and the mediation of chronic cellular stress. At this time, emerging roles for the ligand-RAGE axis in metabolism-mediated modulation of inflammatory signaling in immune cells are being unearthed and add to the growing body of factors underlying pathological immunometabolism.

19.
J Palliat Care ; 26(2): 103-11, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20718395

RESUMO

Although volunteers are widely acknowledged as important members of the palliative care team, their unique contribution to whole-person care has not been well documented or theorized, especially in rural communities. We conducted a focused ethnography in a small rural community, asking key community informants about their understanding of the role of hospice volunteers with dying people and their families. Our results show that these volunteers inhabit a unique third culture of care that fuses elements of formal care with the informal visiting of friends and neighbours. Their role is shaped to a community context where dying is not a private medical event, but rather a whole-person-in-community event, and where care is offered as a natural expression of the interdependence and reciprocity that characterizes rural community life. Our results are a reminder that it takes an entire community to care for the dying, and that hospice volunteers are a crucial link in the network of care that allows people to die with dignity and quality of life.


Assuntos
Redes Comunitárias , Hospitais para Doentes Terminais , Cuidados Paliativos , Serviços de Saúde Rural , Voluntários , Antropologia Cultural , Atitude Frente a Saúde , Hospitais para Doentes Terminais/organização & administração , Humanos , Relações Interpessoais , Ontário , Cuidados Paliativos/organização & administração , Serviços de Saúde Rural/organização & administração , Recursos Humanos
20.
J Palliat Care ; 26(2): 122-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20718397

RESUMO

This study holistically explores the experience of dying and end-of-life care for older persons with dementia in long-term care (LTC) from the perspective of care providers. Using a focused ethnography methodology, seven researchers interviewed LTC staff, residents' families, volunteers, management staff, and spiritual advisers/clergy over a five-day period. Research was guided by two key questions: What is the dying experience of people living in LTC from the perspective of different care providers? and, What are the salient issues in providing palliative care for elderly people dying in LTC? Based on a thematic analysis of verbatim data, three common themes were identified: tension between completing job tasks on time and "being there" for residents; the importance of family-like bonds between front-line staff and residents; and the importance of communication among staff and between staff and residents and their families at the end of life. Findings are discussed in relation to their implications for policies and practices that can support whole-person care and ultimately a good death for residents of LTC facilities.


Assuntos
Demência/terapia , Enfermagem Holística , Instituição de Longa Permanência para Idosos , Casas de Saúde , Cuidados Paliativos , Assistência Terminal , Idoso , Antropologia Cultural , Atitude do Pessoal de Saúde , Atitude Frente a Saúde , Humanos , Assistência de Longa Duração , Ontário , Relações Profissional-Paciente , Carga de Trabalho
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