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1.
Biomed Pharmacother ; 172: 116283, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38377735

RESUMO

BACKGROUND: Galectins (Gal's) are a family of carbohydrate-binding proteins that are known to support the tumour microenvironment through their immunosuppressive activity and ability to promote metastasis. As such they are attractive therapeutic targets, but little is known about the cellular expression pattern of galectins within the tumour and its neighbouring stromal microenvironment. Here we investigated the cellular expression pattern of Gals within pancreatic ductal adenocarcinoma (PDAC). METHODS: Galectin gene and protein expression were analysed by scRNAseq (n=4) and immunofluorescence imaging (n=19) in fibroblasts and epithelial cells of pancreatic biopsies from PDAC patients. Galectin surface expression was also assessed on tumour adjacent normal fibroblasts and cancer associated primary fibroblasts from PDAC biopsies using flow cytometry. RESULTS: scRNAseq revealed higher Gal-1 expression in fibroblasts and higher Gal-3 and -4 expression in epithelial cells. Both podoplanin (PDPN+, stromal/fibroblast) cells and EpCAM+ epithelial cells expressed Gal-1 protein, with highest expression seen in the stromal compartment. By contrast, significantly more Gal-3 and -4 protein was expressed in ductal cells expressing either EpCAM or PDPN, when compared to the stroma. Ductal Gal-4 cellular expression negatively correlated with ductal Gal-1, but not Gal-3 expression. Higher ductal cellular expression of Gal-1 correlated with smaller tumour size and better patient survival. CONCLUSIONS: In summary, the intricate interplay and cell-specific expression patterns of galectins within the PDAC tissue, particularly the inverse correlation between Gal-1 and Gal-4 in ducts and its significant association with patient survival, highlights the complex molecular landscape underlying PDAC and provides valuable insights for future therapeutic interventions.


Assuntos
Benzamidas , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Tirosina/análogos & derivados , Humanos , Molécula de Adesão da Célula Epitelial , Neoplasias Pancreáticas/genética , Carcinoma Ductal Pancreático/genética , Fatores de Transcrição , Galectinas/genética , Microambiente Tumoral
2.
Elife ; 122023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-37350578

RESUMO

Pancreatic ductal adenocarcinoma has a poor clinical outcome and responses to immunotherapy are suboptimal. Stromal fibroblasts are a dominant but heterogenous population within the tumor microenvironment and therapeutic targeting of stromal subsets may have therapeutic utility. Here, we combine spatial transcriptomics and scRNA-Seq datasets to define the transcriptome of tumor-proximal and tumor-distal cancer-associated fibroblasts (CAFs) and link this to clinical outcome. Tumor-proximal fibroblasts comprise large populations of myofibroblasts, strongly expressed podoplanin, and were enriched for Wnt ligand signaling. In contrast, inflammatory CAFs were dominant within tumor-distal subsets and expressed complement components and the Wnt-inhibitor SFRP2. Poor clinical outcome was correlated with elevated HIF-1α and podoplanin expression whilst expression of inflammatory and complement genes was predictive of extended survival. These findings demonstrate the extreme transcriptional heterogeneity of CAFs and its determination by apposition to tumor. Selective targeting of tumor-proximal subsets, potentially combined with HIF-1α inhibition and immune stimulation, may offer a multi-modal therapeutic approach for this disease.


Pancreatic cancer is one of the deadliest and most difficult cancers to treat. It responds poorly to immunotherapy for instance, despite this approach often succeeding in enlisting immune cells to fight tumours in other organs. This may be due, in part, to a type of cell called fibroblasts. Not only do these wrap pancreatic tumours in a dense, protective layer, they also foster complex relationships with the cancerous cells: some fibroblasts may fuel tumour growth, while other may help to contain its spread. These different roles may be linked to spatial location, with fibroblasts adopting different profiles depending on their proximity with cancer calls. For example, certain fibroblasts close to the tumour resemble the myofibroblasts present in healing wounds, while those at the periphery show signs of being involved in inflammation. Being able to specifically eliminate pro-cancer fibroblasts requires a better understanding of the factors that shape the role of these cells, and how to identify them. To examine this problem, Croft et al. relied on tumour samples obtained from pancreatic cancer patients. They mapped out the location of individual fibroblasts in the vicinity of the tumour and analysed their gene activity. These experiments helped to reveal the characteristics of different populations of fibroblasts. For example, they showed that the myofibroblast-like cells closest to the tumour exhibited signs of oxygen deprivation; they also produced podoplanin, a protein known to promote cancer progression. In contrast, cells further from the cancer produced more immune-related proteins. Combining these data with information obtained from patients' clinical records, Croft et al. found that samples from individuals with worse survival outcomes often featured higher levels of podoplanin and hypoxia. Inflammatory markers, however, were more likely to be present in individuals with good outcomes. Overall, these findings could help to develop ways to selectively target fibroblasts that support the growth of pancreatic cancer. Weakening these cells could in turn make the tumour accessible to immune cells, and more vulnerable to immunotherapies.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Transcriptoma , Prognóstico , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/patologia , Fibroblastos/metabolismo , Microambiente Tumoral/genética
3.
Cancer Immunol Res ; 11(4): 435-449, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36689623

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) has a poor clinical outlook. Responses to immune checkpoint blockade are suboptimal and a much more detailed understanding of the tumor immune microenvironment is needed if this situation is to be improved. Here, we characterized tumor-infiltrating T-cell populations in patients with PDAC using cytometry by time of flight (CyTOF) and single-cell RNA sequencing. T cells were the predominant immune cell subset observed within tumors. Over 30% of CD4+ T cells expressed a CCR6+CD161+ Th17 phenotype and 17% displayed an activated regulatory T-cell profile. Large populations of CD8+ tissue-resident memory (TRM) T cells were also present and expressed high levels of programmed cell death protein 1 (PD-1) and TIGIT. A population of putative tumor-reactive CD103+CD39+ T cells was also observed within the CD8+ tumor-infiltrating lymphocytes population. The expression of PD-1 ligands was limited largely to hemopoietic cells whilst TIGIT ligands were expressed widely within the tumor microenvironment. Programmed death-ligand 1 and CD155 were expressed within the T-cell area of ectopic lymphoid structures and colocalized with PD-1+TIGIT+ CD8+ T cells. Combinatorial anti-PD-1 and TIGIT blockade enhanced IFNγ secretion and proliferation of T cells in the presence of PD-1 and TIGIT ligands. As such, we showed that the PDAC microenvironment is characterized by the presence of substantial populations of TRM cells with an exhausted PD-1+TIGIT+ phenotype where dual checkpoint receptor blockade represents a promising avenue for future immunotherapy.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Células T de Memória , Linfócitos T CD8-Positivos , Neoplasias Pancreáticas/metabolismo , Microambiente Tumoral , Receptores Imunológicos/metabolismo
5.
Nat Aging ; 2(6): 536-547, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-37118449

RESUMO

We studied humoral and cellular immunity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 152 long-term care facility staff and 124 residents over a prospective 4-month period shortly after the first wave of infection in England. We show that residents of long-term care facilities developed high and stable levels of antibodies against spike protein and receptor-binding domain. Nucleocapsid-specific responses were also elevated but waned over time. Antibodies showed stable and equivalent levels of functional inhibition against spike-angiotensin-converting enzyme 2 binding in all age groups with comparable activity against viral variants of concern. SARS-CoV-2 seropositive donors showed high levels of antibodies to other beta-coronaviruses but serostatus did not impact humoral immunity to influenza or other respiratory syncytial viruses. SARS-CoV-2-specific cellular responses were similar across all ages but virus-specific populations showed elevated levels of activation in older donors. Thus, survivors of SARS-CoV-2 infection show a robust and stable immunity against the virus that does not negatively impact responses to other seasonal viruses.


Assuntos
COVID-19 , Vacinas contra Influenza , Humanos , Idoso , SARS-CoV-2/genética , Assistência de Longa Duração , Estudos Prospectivos , Casas de Saúde , Anticorpos , Imunidade Celular
6.
Nat Immunol ; 23(1): 40-49, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34937928

RESUMO

SARS-CoV-2 infection is generally mild or asymptomatic in children but a biological basis for this outcome is unclear. Here we compare antibody and cellular immunity in children (aged 3-11 years) and adults. Antibody responses against spike protein were high in children and seroconversion boosted responses against seasonal Beta-coronaviruses through cross-recognition of the S2 domain. Neutralization of viral variants was comparable between children and adults. Spike-specific T cell responses were more than twice as high in children and were also detected in many seronegative children, indicating pre-existing cross-reactive responses to seasonal coronaviruses. Importantly, children retained antibody and cellular responses 6 months after infection, whereas relative waning occurred in adults. Spike-specific responses were also broadly stable beyond 12 months. Therefore, children generate robust, cross-reactive and sustained immune responses to SARS-CoV-2 with focused specificity for the spike protein. These findings provide insight into the relative clinical protection that occurs in most children and might help to guide the design of pediatric vaccination regimens.


Assuntos
Anticorpos Antivirais/imunologia , Coronavirus Humano 229E/imunologia , Coronavirus Humano OC43/imunologia , Proteção Cruzada/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Imunidade Adaptativa/imunologia , Adulto , Anticorpos Neutralizantes/imunologia , COVID-19/imunologia , Vacinas contra COVID-19/imunologia , Criança , Pré-Escolar , Reações Cruzadas/imunologia , Humanos
7.
Oncoimmunology ; 9(1): 1845424, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33299656

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is one of the most common tumor subtypes and remains associated with very poor survival. T cell infiltration into tumor tissue is associated with improved clinical outcome but little is known regarding the potential role of NK cells in disease control. Here we analyze the phenotype and function of NK cells in the blood and tumor tissue from patients with PDAC. Peripheral NK cells are present in normal numbers but display a CD16hiCD57hi phenotype with marked downregulation of NKG2D. Importantly, these cells demonstrate reduced cytotoxic activity and low levels of IFN-γ expression but instead produce high levels of intracellular IL-10, an immunoregulatory cytokine found at increased levels in the blood of PDAC patients. In contrast, NK cells are largely excluded from tumor tissue where they display strong downregulation of both CD16 and CD57, a phenotype that was recapitulated in primary NK cells following co-culture with PDAC organoids. Moreover, expression of activatory proteins, including DNAM-1 and NKP30, was markedly suppressed and the DNAM-1 ligand PVR was strongly expressed on tumor cells. As such, in situ and peripheral NK cells display differential features in patients with PDAC and indicate local and systemic mechanisms by which the tumor can evade immune control. These findings offer a number of potential options for NK-based immunotherapy in the management of patients with PDAC.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Carcinoma Ductal Pancreático/genética , Humanos , Interleucina-10 , Células Matadoras Naturais , Neoplasias Pancreáticas/genética , Fenótipo
8.
Health Info Libr J ; 34(1): 74-85, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28042697

RESUMO

BACKGROUND: The knowledge into action model for NHS Scotland provides a framework for librarians and health care staff to support getting evidence into practice. Central to this model is the development of a network of knowledge brokers to facilitate identification, use, creation and sharing of knowledge. OBJECTIVE: To translate the concepts described in the model into tangible activities with the intention of supporting better use of evidence in health care and subsequently improving patient outcomes. METHODS: Four areas of activity were addressed by small working groups comprising knowledge services staff in local and national boards. The areas of activity were as follows: defining existing and required capabilities and developing learning opportunities for the knowledge broker network; establishing national search and summarising services; developing actionable knowledge tools; and supporting person-to-person knowledge sharing. CONCLUSION: This work presents the development of practical tools and support to translate a conceptual model for getting knowledge into action into a series of activities and outputs to support better use of evidence in health care and subsequently improved patient outcomes.


Assuntos
Medicina Baseada em Evidências , Disseminação de Informação/métodos , Serviços de Informação , Bases de Conhecimento , Humanos , Bibliotecários , Desenvolvimento de Programas , Melhoria de Qualidade , Escócia , Medicina Estatal
9.
Public Health Res Pract ; 26(1): e2611602, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26863165

RESUMO

Although primary care is at the forefront of delivering healthcare to the population, its role in preventing poor health has varied throughout history. Faced with growing demand on healthcare services and a rise in noncommunicable diseases, some health systems are attempting to integrate healthcare delivery with broader population health and wellbeing interventions. Liverpool has a rich history of taking action to improve population health; this paper discusses a range of interventions that have taken place across the city. There is a renewed opportunity to systematise approaches to primary and secondary prevention, strengthened by the lead that general practitioners now have in commissioning health services and their accountability for improved population health outcomes through clinical commissioning groups. This is strongly articulated in the Healthy Liverpool program, a city-wide plan for health and care services. This paper suggests that four key enablers strengthen delivery of public health priorities through primary care: maximising opportunities to identify risk factors for preventable disease, fully exploiting the data collected in primary care to plan and design services, responding to community needs and assets through community engagement, and addressing wider determinants of health through strong partnerships.


Assuntos
Prestação Integrada de Cuidados de Saúde , Nível de Saúde , Atenção Primária à Saúde , Saúde Pública , Humanos , Medicina Estatal , Reino Unido
10.
Health Info Libr J ; 25(2): 125-34, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18494647

RESUMO

BACKGROUND: Using specific examples, this paper describes the tools, methods and resources used to develop Managed Knowledge Networks (MKNs) within the NHS Scotland e-Library (http://www.elib.scot.nhs.uk). MKNs help to complete the knowledge management cycle by providing a place to share the learning and discuss the evidence for practice through combining the use of the published material (explicit knowledge) with the experience and knowledge held by individuals, communities and organizations (tacit knowledge). OBJECTIVES: First of all, this paper outlines the e-Library infrastructure, which provides an inter-operable framework to manage the published knowledge using a metadata management system; and a knowledge-sharing tool to support the development of MKNs. It then covers the various stages involved in developing an MKN: gathering and analysing information needs in a variety of ways; presenting and organizing the resources and services for the users as identified in the needs analysis; managing the tacit, personal and local knowledge. CONCLUSION: The toolkit described enables the Knowledge Services Group to take the needs of users, transcribe these into Specialist e-Libraries to provide access to the published information and to support this with accessing and sharing the knowledge of colleagues via MKNs.


Assuntos
Redes de Comunicação de Computadores , Conhecimentos, Atitudes e Prática em Saúde , Bibliotecas Médicas/organização & administração , Modelos Educacionais , Educação de Pacientes como Assunto/organização & administração , Simulação por Computador , Humanos , Modelos Organizacionais , Política Organizacional , Desenvolvimento de Programas , Escócia , Medicina Estatal/organização & administração
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