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1.
Artículo en Inglés | MEDLINE | ID: mdl-39109853

RESUMEN

Investigating the interactions between nanomaterials and the cells they are likely to encounter in vivo is a critical aspect of designing nanomedicines for imaging and therapeutic applications. Immune cells such as dendritic cells, macrophages, and myeloid derived suppressor cells have a frontline role in the identification and removal of foreign materials from the body, with interactions shown to be heavily dependent on variables such as nanoparticle size, charge, and surface chemistry. Interactions such as cellular association or uptake of nanoparticles can lead to diminished functionality or rapid clearance from the body, making it critical to consider these interactions when designing and synthesizing nanomaterials for biomedical applications ranging from drug delivery to imaging and biosensing. We investigated the interactions between PEGylated organosilica nanoparticles and naturally endocytic immune cells grown from stem cells in murine bone marrow. Specifically, we varied the particle size from 60 nm up to 1000 nm and investigated the effects of size on immune cell association, activation, and maturation with these critical gatekeeper cells. These results will help inform future design parameters for in vitro and in vivo biomedical applications utilizing organosilica nanoparticles.

2.
Front Endocrinol (Lausanne) ; 14: 1231043, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38027197

RESUMEN

Congenital hyperinsulinism (CHI) is a condition characterised by severe and recurrent hypoglycaemia in infants and young children caused by inappropriate insulin over-secretion. CHI is of heterogeneous aetiology with a significant genetic component and is often unresponsive to standard medical therapy options. The treatment of CHI can be multifaceted and complex, requiring multidisciplinary input. It is important to manage hypoglycaemia in CHI promptly as the risk of long-term neurodisability arising from neuroglycopaenia is high. The UK CHI consensus on the practice and management of CHI was developed to optimise and harmonise clinical management of patients in centres specialising in CHI as well as in non-specialist centres engaged in collaborative, networked models of care. Using current best practice and a consensus approach, it provides guidance and practical advice in the domains of diagnosis, clinical assessment and treatment to mitigate hypoglycaemia risk and improve long term outcomes for health and well-being.


Asunto(s)
Hiperinsulinismo Congénito , Niño , Lactante , Humanos , Preescolar , Consenso , Hiperinsulinismo Congénito/diagnóstico , Hiperinsulinismo Congénito/genética , Hiperinsulinismo Congénito/terapia , Pancreatectomía , Reino Unido
3.
Nutrients ; 14(20)2022 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-36297122

RESUMEN

Insulin resistance (IR) and chronic low-grade inflammation are risk factors for chronic diseases including type 2 diabetes (T2D) and cardiovascular disease. This study aimed to investigate two dietary indices: Mediterranean Diet Score (MDS) and Dietary Inflammatory Index (DII®), and their associations with direct measures of glucose metabolism and adiposity, and biochemical measures including lipids, cytokines and adipokines in overweight/obese adults. This cross-sectional study included 65 participants (males = 63%; age 31.3 ± 8.5 years). Dietary intake via 3-day food diaries was used to measure adherence to MDS (0-45 points); higher scores indicating adherence. Energy-adjusted DII (E-DII) scores were calculated with higher scores indicating a pro-inflammatory diet. IR was assessed using hyperinsulinemic euglycemic clamps, insulin secretion by intravenous glucose tolerance test, adiposity by dual-energy X-ray absorptiometry, and circulating cytokine and adipokine concentrations by multiplex assays. Higher MDS was associated with greater insulin sensitivity (ß = 0.179; 95%CI: 0.39, 0.318) after adjusting for age, sex and % body fat, and lower NF-κB, higher adiponectin and adipsin in unadjusted and adjusted models. Higher E-DII score was associated with increased total cholesterol (ß = 0.364; 95%CI: 0.066, 0.390) and LDL-cholesterol (ß = 0.305; 95%CI: 0.019, 0.287) but not with adiposity, glucose metabolism, cytokines or adipokines. Greater MDS appears to be associated with decreased IR and inflammatory markers in overweight/obese adults.


Asunto(s)
Diabetes Mellitus Tipo 2 , Dieta Mediterránea , Resistencia a la Insulina , Adulto , Humanos , Masculino , Adulto Joven , Adipoquinas/metabolismo , Adiponectina , Biomarcadores , Colesterol , Factor D del Complemento , Estudios Transversales , Citocinas , Dieta , Glucosa , Inflamación , Lípidos , FN-kappa B , Obesidad/complicaciones , Obesidad/metabolismo , Sobrepeso/complicaciones
4.
J Am Heart Assoc ; 11(12): e025629, 2022 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-35699195

RESUMEN

Background Cerebral small-vessel disease (cSVD) is an important cause of stroke and vascular dementia. Most cases are multifactorial, but an emerging minority have a monogenic cause. While NOTCH3 is the best-known gene, several others have been reported. We aimed to summarize the cerebral phenotypes associated with these more recent cSVD genes. Methods and Results We performed a systematic review (PROSPERO [International Prospective Register of Systematic Reviews]: CRD42020196720), searching Medline/Embase (conception to July 2020) for any language publications describing COL4A1/2, TREX1, HTRA1, ADA2, or CTSA pathogenic variant carriers. We extracted data about individuals' characteristics and clinical and vascular radiological cerebral phenotypes. We summarized phenotype frequencies per gene, comparing patterns across genes. We screened 6485 publications including 402, and extracted data on 390 individuals with COL4A1, 123 with TREX1, 44 with HTRA1 homozygous, 41 with COL4A2, 346 with ADA2, 82 with HTRA1 heterozygous, and 14 with CTSA. Mean age ranged from 15 (ADA2) to 59 years (HTRA1 heterozygotes). Clinical phenotype frequencies varied widely: stroke, 9% (TREX1) to 52% (HTRA1 heterozygotes); cognitive features, 0% (ADA2) to 64% (HTRA1 homozygotes); and psychiatric features, 0% (COL4A2; ADA2) to 57% (CTSA). Among individuals with neuroimaging, vascular radiological phenotypes appeared common, ranging from 62% (ADA2) to 100% (HTRA1 homozygotes; CTSA). White matter lesions were the most common pathology, except in ADA2 and COL4A2 cases, where ischemic and hemorrhagic lesions dominated, respectively. Conclusions There appear to be differences in cerebral manifestations across cSVD genes. Vascular radiological changes were more common than clinical neurological phenotypes, and present in the majority of individuals with reported neuroimaging. However, these results may be affected by age and biases inherent to case reports. In the future, better characterization of associated phenotypes, as well as insights from population-based studies, should improve our understanding of monogenic cSVD to inform genetic testing, guide clinical management, and help unravel underlying disease mechanisms.


Asunto(s)
Enfermedades de los Pequeños Vasos Cerebrales , Accidente Cerebrovascular , Humanos , Enfermedades de los Pequeños Vasos Cerebrales/complicaciones , Enfermedades de los Pequeños Vasos Cerebrales/diagnóstico por imagen , Enfermedades de los Pequeños Vasos Cerebrales/genética , Serina Peptidasa A1 que Requiere Temperaturas Altas/genética , Mutación , Fenotipo , Accidente Cerebrovascular/complicaciones
5.
Biomedicines ; 9(11)2021 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-34829783

RESUMEN

Ovarian cancer remains as one of the most lethal gynecological cancers to date, with major challenges associated with screening, diagnosis and treatment of the disease and an urgent need for new technologies that can meet these challenges. Nanomaterials provide new opportunities in diagnosis and therapeutic management of many different types of cancers. In this review, we highlight recent promising developments of nanoparticles designed specifically for the detection or imaging of ovarian cancer that have reached the preclinical stage of development. This includes contrast agents, molecular imaging agents and intraoperative aids that have been designed for integration into standard imaging procedures. While numerous nanoparticle systems have been developed for ovarian cancer detection and imaging, specific design criteria governing nanomaterial targeting, biodistribution and clearance from the peritoneal cavity remain key challenges that need to be overcome before these promising tools can accomplish significant breakthroughs into the clinical setting.

6.
Cancers (Basel) ; 13(16)2021 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-34439354

RESUMEN

Autoantibodies recognising phosphorylated heat shock factor 1 (HSF1-PO4) protein are suggested as potential new diagnostic biomarkers for early-stage high-grade serous ovarian cancer (HGSOC). We predicted in silico B-cell epitopes in human and murine HSF1. Three epitope regions were synthesised as peptides. Circulating immunoglobulin A (cIgA) against the predicted peptide epitopes or HSF1-PO4 was measured using ELISA, across two small human clinical trials of HGSOC patients at diagnosis. To determine whether chemotherapy would promote changes in reactivity to either HSF1-PO4 or the HSF-1 peptide epitopes, IgA responses were further assessed in a sample of patients after a full cycle of chemotherapy. Anti-HSF1-PO4 responses correlated with antibody responses to the three selected epitope regions, regardless of phosphorylation, with substantial cross-recognition of the corresponding human and murine peptide epitope variants. Assessing reactivity to individual peptide epitopes, compared to HSF1-PO4, improved assay sensitivity. IgA responses to HSF1-PO4 further increased significantly post treatment, indicating that HSF1-PO4 is a target for immunity in response to chemotherapy. Although performed in a small cohort, these results offer potential insights into the interplay between autoimmunity and ovarian cancer and offer new peptide biomarkers for early-stage HGSOC diagnosis, to monitor responses to chemotherapy, and widely for pre-clinical HGSOC research.

7.
Int J Mol Sci ; 22(16)2021 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-34445670

RESUMEN

While first and foremost considered a respiratory infection, COVID-19 can result in complications affecting multiple organs. Immune responses in COVID-19 can both protect against the disease as well as drive it. Insights into these responses, and specifically the targets being recognised by the immune system, are of vital importance in understanding the side effects of COVID-19 and associated pathologies. The body's adaptive immunity recognises and responds against specific targets (antigens) expressed by foreign pathogens, but not usually to target self-antigens. However, if the immune system becomes dysfunctional, adaptive immune cells can react to self-antigens, which can result in autoimmune disease. Viral infections are well reported to be associated with, or exacerbate, autoimmune diseases such as multiple sclerosis (MS) and systemic lupus erythematosus (SLE). In COVID-19 patients, both new onset MS and SLE, as well as the occurrence of other autoimmune-like pathologies, have been reported. Additionally, the presence of autoantibodies, both with and without known associations to autoimmune diseases, have been found. Herein we describe the mechanisms of virally induced autoimmunity and summarise some of the emerging reports on the autoimmune-like diseases and autoreactivity that is reported to be associated with SARS-CoV-2 infection.


Asunto(s)
Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/virología , COVID-19/inmunología , Inmunidad Adaptativa , Artritis Reumatoide/inmunología , Autoanticuerpos/inmunología , Autoantígenos/inmunología , Autoinmunidad , COVID-19/virología , Humanos , Lupus Eritematoso Sistémico/inmunología , SARS-CoV-2/inmunología
8.
J Proteome Res ; 20(5): 2618-2627, 2021 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-33823594

RESUMEN

New approaches to rapid, simple, in vitro diagnostic immunoassays that do not rely on centralized laboratory facilities are urgently needed for disease diagnosis and to inform treatment strategies. The recent and ongoing COVID-19 pandemic has emphasized that rapid diagnostics are needed to help guide government policies on quarantines, social distancing measures, and community lockdowns. A common approach to developing new immunoassays is to modify existing platforms (e.g., automated ELISA and lateral flow assays) for the new analyte, even though this does not address the drawbacks of existing platforms. An alternate approach is to search for robust assays that have been superseded but could in fact solve important challenges using modern technologies. Immunodiffusion is one such platform based on unique "precipitin ring" patterns formed in gels or paper following interactions between proteins and cognate antibodies in diffusion/reaction systems. Herein, we investigate the microstructure of these precipitin rings using a combination of fluorescence and electron microscopy and also perform a mass spectrometry investigation to determine the proteomic composition of the rings. We observed that the rings were composed of microparticles, which we termed "precipitin complexes", and that these complexes were composed of at least 19 key proteins, including immunoglobulins and complement factors along with a range of plasma proteins, possibly related to immune complexes and/or high-density lipoprotein particles. This information will be useful in developing new in vitro diagnostics using reaction/diffusion systems-techniques that require a single assay step and that only require calibrated length measurements for target protein quantification.


Asunto(s)
COVID-19 , Proteómica , Control de Enfermedades Transmisibles , Humanos , Inmunodifusión , Microscopía , Pandemias , Precipitinas , SARS-CoV-2
9.
Cancers (Basel) ; 13(3)2021 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-33513866

RESUMEN

Immunity plays a key role in epithelial ovarian cancer (EOC) progression with a well-documented correlation between patient survival and high intratumoral CD8+ to T regulatory cell (Treg) ratios. We previously identified dysregulated DPP4 activity in EOCs as a potentially immune-disruptive influence contributing to a reduction in CXCR3-mediated T-cell infiltration in solid tumours. We therefore hypothesized that inhibition of DPP4 activity by sitagliptin, an FDA-approved inhibitor, would improve T-cell infiltration and function in a syngeneic ID8 mouse model of EOC. Daily oral sitagliptin at 50 mg/kg was provided to mice with established primary EOCs. Sitagliptin treatment decreased metastatic tumour burden and significantly increased overall survival and was associated with significant changes to the immune landscape. Sitagliptin increased overall CXCR3-mediated CD8+ T-cell trafficking to the tumour and enhanced the activation and proliferation of CD8+ T-cells in tumour tissue and the peritoneal cavity. Substantial reductions in suppressive cytokines, including CCL2, CCL17, CCL22 and IL-10, were also noted and were associated with reduced CD4+ CD25+ Foxp3+ Treg recruitment in the tumour. Combination therapy with paclitaxel, however, typical of standard-of-care for patients in palliative care, abolished CXCR3-specific T-cell recruitment stimulated by sitagliptin. Our data suggest that sitagliptin may be suitable as an adjunct therapy for patients between chemotherapy cycles as a novel approach to enhance immunity, optimise T-cell-mediated function and improve overall survival.

10.
Front Bioinform ; 1: 709533, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-36303764

RESUMEN

COVID-19, caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), whilst commonly characterised as a respiratory disease, is reported to have extrapulmonary manifestations in multiple organs. Extrapulmonary involvement in COVID-19 includes autoimmune-like diseases such as Guillain-Barré syndrome and Kawasaki disease, as well as the presence of various autoantibodies including those associated with autoimmune diseases such a systemic lupus erythematosus (e.g. ANA, anti-La). Multiple strains of SARS-CoV-2 have emerged globally, some of which are found to be associated with increased transmissibility and severe disease. We performed an unbiased comprehensive mapping of the potential for cross-reactivity with self-antigens across multiple SARS-CoV-2 proteins and compared identified immunogenic regions across multiples strains. Using the Immune Epitope Database (IEDB) B cell epitope prediction tool, regions predicted as antibody epitopes with high prediction scores were selected. Epitope sequences were then blasted to eight other global strains to identify mutations within these regions. Of the 15 sequences compared, eight had a mutation in at least one other global strain. Predicted epitopes were then compared to human proteins using the NCBI blast tool. In contrast to studies focusing on short sequences of peptide identity, we have taken an immunological approach to selection criteria for further analysis and have identified 136 alignments of 6-23 amino acids (aa) in 129 human proteins that are immunologically likely to be cross-reactive with SARS-CoV-2. Additionally, to identify regions with significant potential to interfere with host cell function-or promote immunopathology, we identified epitope regions more likely to be accessible to pathogenic autoantibodies in the host, selected using a novel combination of sequence similarity, and modelling protein and alignment localization with a focus on extracellular regions. Our analysis identified 11 new predicted B-cell epitopes in host proteins, potentially capable of explaining key aspects of COVID-19 extrapulmonary pathology, and which were missed in other in silico studies which used direct identity rather than immunologically related functional criteria.

11.
Vaccines (Basel) ; 8(4)2020 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-33153189

RESUMEN

Vaccines against blood-stage malaria often aim to induce antibodies to neutralize parasite entry into red blood cells, interferon gamma (IFNγ) produced by T helper 1 (Th1) CD4+ T cells or interleukin 4 (IL-4) produced by T helper 2 (Th2) cells to provide B cell help. One vaccine delivery method for suitable putative malaria protein antigens is the use of nanoparticles as vaccine carriers. It has been previously shown that antigen conjugated to inorganic nanoparticles in the viral-particle size range (~40-60 nm) can induce protective antibodies and T cells against malaria antigens in a rodent malaria challenge model. Herein, it is shown that biodegradable pullulan-coated iron oxide nanoparticles (pIONPs) can be synthesized in this same size range. The pIONPs are non-toxic and do not induce conventional pro-inflammatory cytokines in vitro and in vivo. We show that murine blood-stage antigen MSP4/5 from Plasmodium yoelii could be chemically conjugated to pIONPs and the use of these conjugates as immunogens led to the induction of both specific antibodies and IFNγ CD4+ T cells reactive to MSP4/5 in mice, comparable to responses to MSP4/5 mixed with classical adjuvants (e.g., CpG or Alum) that preferentially induce Th1 or Th2 cells individually. These results suggest that biodegradable pIONPs warrant further exploration as carriers for developing blood-stage malaria vaccines.

12.
Vaccines (Basel) ; 8(3)2020 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-32932705

RESUMEN

Dendritic cells (DCs) are commonly generated from bone marrow (BM) progenitor cells with granulocyte-macrophage colony-stimulating factor (GM-CSF) alone or in combination with interleukin 4 (IL-4). These cells are often harvested post day 5, when they acquire maturation markers and can stimulate T cells. Apart from DCs, myeloid derived suppressor cells (MDSCs) are also found within these cultures. However, little is known about the functional characteristics of DCs and MDSCs before day 5. Herein, using a murine model, it is shown that early DCs and MDSCs, even in cultures with GM-CSF alone, upregulate fully maturation and activation surface molecules in response to the toll-like receptor 4 (TLR4) ligand lipopolysaccharide (LPS) stimulation. Despite initially displaying lower marker expression levels, these cells efficiently induced T cell stimulation and cytokine production. Interestingly, Gr-1int MDSCs increased their T cell co-stimulatory activity upon TLR4 stimulation. Additionally, early DCs and MDSCs exhibited differential endocytic capacity for viral sized nanoparticles and bacterial sized microparticles. DCs internalized both particle sizes, whilst MDSCs only internalized the larger microparticles, with reduced endocytic activity over time in the culture. These findings have unveiled an important role for the rapid initiation of productive immunity by GM-CSF, with promising implications for future vaccine and DC immunotherapy developments.

13.
Stroke ; 51(10): 3007-3017, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32842921

RESUMEN

BACKGROUND AND PURPOSE: An important minority of cerebral small vessel disease (cSVD) is monogenic. Many monogenic cSVD genes are recognized to be associated with extracerebral phenotypes. We assessed the frequency of these phenotypes in existing literature. METHODS: We performed a systematic review following the PRISMA guidelines (Preferred Reporting Items for Systematic Reviews and Meta-Analyses), searching Medline/Embase for publications describing individuals with pathogenic variants in COL4A1/2, TREX1, HTRA1, ADA2, and CTSA genes (PROSPERO 74804). We included any publication reporting on ≥1 individual with a pathogenic variant and their clinically relevant phenotype. We extracted individuals' characteristics and information about associated extracerebral phenotypes and stroke/transient ischemic attack. We noted any novel extracerebral phenotypes and looked for shared phenotypes between monogenic cSVDs. RESULTS: After screening 6048 publications, we included 96 COL4A1 (350 individuals), 32 TREX1 (115 individuals), 43 HTRA1 (38 homozygous/61 heterozygous individuals), 16 COL4A2 (37 individuals), 119 ADA2 (209 individuals), and 3 CTSA (14 individuals) publications. The majority of individuals originated from Europe/North America, except for HTRA1, where most were from Asia. Age varied widely, ADA2 individuals being youngest and heterozygous HTRA1/CTSA individuals oldest. Sex distribution appeared equal. Extracerebral phenotypes were common: 14% to 100% of individuals with a pathogenic variant manifested at least one extracerebral phenotype (14% COL4A2, 43% HTRA1 heterozygotes, 47% COL4A1, 57% TREX1, 91% ADA2, 94% HTRA1 homozygotes, and 100% CTSA individuals). Indeed, for 4 of 7 genes, an extracerebral phenotype was observed more frequently than stroke/transient ischemic attack. Ocular, renal, hepatic, muscle, and hematologic systems were each involved in more than one monogenic cSVD. CONCLUSIONS: Extracerebral phenotypes are common in monogenic cSVD with extracerebral system involvement shared between genes. However, inherent biases in the existing literature mean that further data from large-scale population-based longitudinal studies collecting health outcomes in a systematic unbiased way is warranted. The emerging knowledge will help to select patients for testing, inform clinical management, and provide further insights into the underlying mechanisms of cSVD.


Asunto(s)
Enfermedades de los Pequeños Vasos Cerebrales/genética , Genotipo , Heterocigoto , Humanos , Mutación , Fenotipo
14.
Neurology ; 95(6): e697-e707, 2020 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-32616677

RESUMEN

OBJECTIVE: In UK Biobank (UKB), a large population-based prospective study, cases of many diseases are ascertained through linkage to routinely collected, coded national health datasets. We assessed the accuracy of these for identifying incident strokes. METHODS: In a regional UKB subpopulation (n = 17,249), we identified all participants with ≥1 code signifying a first stroke after recruitment (incident stroke-coded cases) in linked hospital admission, primary care, or death record data. Stroke physicians reviewed their full electronic patient records (EPRs) and generated reference standard diagnoses. We evaluated the number and proportion of cases that were true-positives (i.e., positive predictive value [PPV]) for all codes combined and by code source and type. RESULTS: Of 232 incident stroke-coded cases, 97% had EPR information available. Data sources were 30% hospital admission only, 39% primary care only, 28% hospital and primary care, and 3% death records only. While 42% of cases were coded as unspecified stroke type, review of EPRs enabled a pathologic type to be assigned in >99%. PPVs (95% confidence intervals) were 79% (73%-84%) for any stroke (89% for hospital admission codes, 80% for primary care codes) and 83% (74%-90%) for ischemic stroke. PPVs for small numbers of death record and hemorrhagic stroke codes were low but imprecise. CONCLUSIONS: Stroke and ischemic stroke cases in UKB can be ascertained through linked health datasets with sufficient accuracy for many research studies. Further work is needed to understand the accuracy of death record and hemorrhagic stroke codes and to develop scalable approaches for better identifying stroke types.


Asunto(s)
Accidente Cerebrovascular/epidemiología , Adulto , Anciano , Isquemia Encefálica/epidemiología , Recolección de Datos/métodos , Conjuntos de Datos como Asunto , Certificado de Defunción , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Incidencia , Clasificación Internacional de Enfermedades , Masculino , Persona de Mediana Edad , Admisión del Paciente/estadística & datos numéricos , Atención Primaria de Salud/estadística & datos numéricos , Estudios Prospectivos , Reino Unido/epidemiología
15.
Int J Mol Sci ; 21(13)2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32630213

RESUMEN

Peptide-based vaccines can be safer and more cost effective than whole organism vaccines. Previous studies have shown that inorganic polystyrene nanoparticles (PSNPs) covalently conjugated to the minimal immunodominant peptide epitope from murine liver stage malaria (SYIPSAEKI) induced potent CD8+ T cell responses. Many pathogens, including malaria, have polymorphic T cell epitope regions. Amino acid changes in positions that are contact residues for the T cell receptor (TCR) often alter the specific cross-reactivity induced by the peptide antigen, and it is largely assumed that changes outside of these residues have little impact. Herein, each amino acid residue (except major histocompatibility complex (MHC) anchors) was systematically changed to an alanine. Peptide epitopes with altered amino acids outside T cell contact residues were still recognized by T cells induced by PSNPs-SYIPSAEKI (KI) vaccines, albeit at lower levels, except for the variant SYIPSAAKI (A7). PSNPs-SYIPSAAKI vaccines further elicited high responses to the index KI peptide. None of the epitopes displayed altered peptide ligand (APL) antagonism in vitro, and re-stimulating SYIPSAEKI and SYIPSAAKI together synergistically enhanced IFN-γ production by the T cells. These results show epitope variation in non-TCR recognition residues can have effects on T cell reactivity, suggesting that such natural variation may also be driven by immune pressure. Additionally, when re-modelling peptides to enhance the cross-reactivity of vaccines, both TCR recognition and non-recognition residues should be considered.


Asunto(s)
Epítopos de Linfocito T/inmunología , Epítopos Inmunodominantes/inmunología , Secuencia de Aminoácidos/genética , Aminoácidos/genética , Animales , Linfocitos T CD8-positivos/metabolismo , Mapeo Epitopo/métodos , Epítopos de Linfocito T/metabolismo , Epítopos Inmunodominantes/metabolismo , Complejo Mayor de Histocompatibilidad/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Fragmentos de Péptidos/metabolismo , Péptidos/inmunología , Receptores de Antígenos de Linfocitos T/metabolismo , Vacunas de Subunidad/inmunología
16.
Biomolecules ; 10(6)2020 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-32570769

RESUMEN

Stingless bees are a type of honey producers that commonly live in tropical countries. Their use for honey is being abandoned due to its limited production. However, the recent improvements in stingless bee honey production, particularly in South East Asia, have brought stingless bee products back into the picture. Although there are many stingless bee species that produce a wide spread of products, known since old eras in traditional medicine, the modern medical community is still missing more investigational studies on stingless bee products. Whereas comprehensive studies in the current era attest to the biological and medicinal properties of honeybee (Apis mellifera) products, the properties of stingless bee products are less known. This review highlights for the first time the medicinal benefits of stingless bee products (honey, propolis, pollen and cerumen), recent investigations and promising future directions. This review emphasizes the potential antioxidant properties of these products that in turn play a vital role in preventing and treating diseases associated with oxidative stress, microbial infections and inflammatory disorders. Summarizing all these data and insights in one manuscript may increase the commercial value of stingless bee products as a food ingredient. This review will also highlight the utility of stingless bee products in the context of medicinal and therapeutic properties, some of which are yet to be discovered.


Asunto(s)
Antiinfecciosos/farmacología , Antineoplásicos Fitogénicos/farmacología , Antioxidantes/farmacología , Miel/análisis , Animales , Antiinfecciosos/química , Antineoplásicos Fitogénicos/química , Antioxidantes/química , Abejas , Humanos , Estructura Molecular
17.
Vaccines (Basel) ; 8(2)2020 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-32485944

RESUMEN

Sustained immune responses, particularly antibody responses, are key for protection against many endemic infectious diseases. Antibody responses are often accompanied by T helper (Th) cell immunity. Herein we study small biodegradable poly (ethylene glycol)-b-poly (lactic-co-glycolic acid) nanoparticles (PEG-b-PLGA NPs, 25-50 nm) as antigen- or adjuvant-carriers. The antigen carrier function of PEG-b-PLGA NPs was compared against an experimental benchmark polystyrene nanoparticles (PS NPs, 40-50 nm), both conjugated with the model antigen ovalbumin (OVA-PS NPs, and OVA-PEG-b-PLGA NPs). The OVA-PEG-b-PLGA NPs induced sustained antibody responses to Day 120 after two immunizations. The OVA-PEG-b-PLGA NPs as a self-adjuvanting vaccine further induced IL-4 producing T-helper cells (Th2), but not IFN-γ producing T-cells (Th1). The PEG-b-PLGA NPs as a carrier for CpG adjuvant (CpG-PEG-b-PLGA NPs) were also tested as mix-in vaccine adjuvants comparatively for protein antigens, or for protein-conjugated to PS NPs or to PEG-b-PLGA NPs. While the addition of this adjuvant NP did not further increase T-cell responses, it improved the consistency of antibody responses across all immunization groups. Together these data support further development of PEG-b-PLGA NPs as a vaccine carrier, particularly where it is desired to induce Th2 immunity and achieve sustained antibody titers in the absence of affecting Th1 immunity.

18.
Cancers (Basel) ; 12(3)2020 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-32183059

RESUMEN

Cancer-related deaths are approaching 10 million each year. Survival statistics for some cancers, such as ovarian cancer, have remained unchanged for decades, with women diagnosed at stage III or IV having over 80% chance of a lethal cancer recurrence after standard first-line treatment (reductive surgery and chemotherapy). New treatments and adjunct therapies are needed. In ovarian cancer, as in other cancers, the immune response, particularly cytotoxic (CD8+) T cells are correlated with a decreased risk of recurrence. As well as completely new antigen targets resulting from DNA mutations (neo-antigens), these T cells recognize cancer-associated overexpressed, re-expressed or modified self-proteins. However, there is concern that activation of self-reactive responses may also promote off-target pathology. This review considers the complex interplay between cancer-reactive and self-reactive immune cells and discusses the potential uses for various leading immunomodulatory compounds, derived from plant-based sources, as a cancer therapy option or to modulate potential autoimmune pathology. Along with reviewing well-studied compounds such as curcumin (from turmeric), epigallocatechin gallate (EGCG, from green tea) and resveratrol (from grapes and certain berries), it is proposed that compounds from novel sources, for example, native Australian plants, will provide a useful source for the fine modulation of cancer immunity in patients.

19.
Philos Trans A Math Phys Eng Sci ; 378(2168): 20190389, 2020 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-32063177

RESUMEN

The main pond within the historic Royal Botanic Garden Edinburgh is an important component of urban blue-green infrastructure. This paper reports on flood resilience provided by the pond (simulated using the CityCAT hydrodynamic model), its water residence times (obtained using the Shetran hydrological model), and the ecology and biodiversity (vascular plants, bryophytes, aquatic invertebrates, phyto- and zooplankton, birds) of the pond and the adjacent area. The results show that the pond improves the flood resilience with at least a 27% reduction in the peak discharge during a 1 h, one in 100-year event. The area represents a biodiversity hot spot with a range of native taxa occurring among introduced plant species. The plankton community is dominated by diatoms, reflecting elevated levels of turbulence and a relatively short residence time, with an average value of 10 days. Analysis of macroinvertebrate community indicates a potential for water quality improvement. The results are discussed in relation to multiple societal benefits related to flood resilience, recreation, education, water quality, amenity and biodiversity value. The conclusions may prove particularly valuable for introducing practical measures in the water catchment, preventing waterlogging of the soil and ensuring an uninterrupted supply of public services. This article is part of the theme issue 'Urban flood resilience'.


Asunto(s)
Biodiversidad , Ciudades , Inundaciones , Conservación de los Recursos Naturales , Hidrodinámica , Hidrología , Modelos Teóricos , Plantas , Lluvia , Calidad del Agua
20.
Nurs Older People ; 32(1): 27-33, 2020 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-31769256

RESUMEN

Dehydration is prevalent in hospitalised older people and residents in care homes, and older people with dementia are particularly at risk. A literature review was conducted to determine the evidence-based interventions used to prevent and manage dehydration in older people with dementia. Three databases were searched for relevant literature: Applied Social Sciences Index and Abstracts, Cumulative Index to Nursing and Allied Health Literature, and MEDLINE, alongside hand-searching. In-depth reading of the 12 studies included in this literature review was undertaken. Five themes were identified in relation to the hydration of older people: physical and social environment; staff communication strategies; access to drinks; drinking vessels; and individual preferences. The evidence suggests that dehydration in older people with dementia is an ongoing concern that needs to be addressed. There is evidence supporting the use of essential nursing interventions to improve hydration, such as coloured cups and verbal prompts, but less is known about the barriers preventing nurses from implementing these evidence-based interventions.


Asunto(s)
Deshidratación , Demencia , Humanos , Anciano , Deshidratación/prevención & control , Casas de Salud , Demencia/complicaciones
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