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1.
Mol Biol Evol ; 39(1)2022 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-34897511

RESUMEN

Penguins (Sphenisciformes) are an iconic order of flightless, diving seabirds distributed across a large latitudinal range in the Southern Hemisphere. The extensive area over which penguins are endemic is likely to have fostered variation in pathogen pressure, which in turn will have imposed differential selective pressures on the penguin immune system. At the front line of pathogen detection and response, the Toll-like receptors (TLRs) provide insight into host evolution in the face of microbial challenge. TLRs respond to conserved pathogen-associated molecular patterns and are frequently found to be under positive selection, despite retaining specificity for defined agonist classes. We undertook a comparative immunogenetics analysis of TLRs for all penguin species and found evidence of adaptive evolution that was largely restricted to the cell surface-expressed TLRs, with evidence of positive selection at, or near, key agonist-binding sites in TLR1B, TLR4, and TLR5. Intriguingly, TLR15, which is activated by fungal products, appeared to have been pseudogenized multiple times in the Eudyptes spp., but a full-length form was present as a rare haplotype at the population level. However, in vitro analysis revealed that even the full-length form of Eudyptes TLR15 was nonfunctional, indicating an ancestral cryptic pseudogenization prior to its eventual disruption multiple times in the Eudyptes lineage. This unusual pseudogenization event could provide an insight into immune adaptation to fungal pathogens such as Aspergillus, which is responsible for significant mortality in wild and captive bird populations.


Asunto(s)
Spheniscidae , Animales , Evolución Molecular , Selección Genética , Spheniscidae/genética , Receptores Toll-Like/genética
2.
BMC Genomics ; 22(1): 719, 2021 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-34610803

RESUMEN

BACKGROUND: Despite increasing interest in γδ T cells and their non-classical behaviour, most studies focus on animals with low numbers of circulating γδ T cells, such as mice and humans. Arguably, γδ T cell functions might be more prominent in chickens where these cells form a higher proportion of the circulatory T cell compartment. The TCR repertoire defines different subsets of γδ T cells, and such analysis is facilitated by well-annotated TCR loci. γδ T cells are considered at the cusp of innate and adaptive immunity but most functions have been identified in γδ low species. A deeper understanding of TCR repertoire biology in γδ high and γδ low animals is critical for defining the evolution of the function of γδ T cells. Repertoire dynamics will reveal populations that can be classified as innate-like or adaptive-like as well as those that straddle this definition. RESULTS: Here, a recent discrepancy in the structure of the chicken TCR gamma locus is resolved, demonstrating that tandem duplication events have shaped the evolution of this locus. Importantly, repertoire sequencing revealed large differences in the usage of individual TRGV genes, a pattern conserved across multiple tissues, including thymus, spleen and the gut. A single TRGV gene, TRGV3.3, with a highly diverse private CDR3 repertoire dominated every tissue in all birds. TRGV usage patterns were partly explained by the TRGV-associated recombination signal sequences. Public CDR3 clonotypes represented varying proportions of the repertoire of TCRs utilising different TRGVs, with one TRGV dominated by super-public clones present in all birds. CONCLUSIONS: The application of repertoire analysis enabled functional annotation of the TCRG locus in a species with a high circulating γδ phenotype. This revealed variable usage of TCRGV genes across multiple tissues, a pattern quite different to that found in γδ low species (human and mouse). Defining the repertoire biology of avian γδ T cells will be key to understanding the evolution and functional diversity of these enigmatic lymphocytes in an animal that is numerically more reliant on them. Practically, this will reveal novel ways in which these cells can be exploited to improve health in medical and veterinary contexts.


Asunto(s)
Pollos , Genoma , Receptores de Antígenos de Linfocitos T gamma-delta , Animales , Pollos/genética , Genómica , Receptores de Antígenos de Linfocitos T gamma-delta/genética , Linfocitos T
4.
Eur J Immunol ; 43(7): 1940-52, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23589155

RESUMEN

Licensed seasonal influenza vaccines induce antibody (Ab) responses against influenza hemagglutinin (HA) that are limited in their ability to protect against different strains of influenza. Cytotoxic T lymphocytes recognizing the conserved internal nucleoprotein (NP) and matrix protein (M1) are capable of mediating a cross-subtype immune response against influenza. Modified vaccinia Ankara (MVA) virus encoding NP and M1 (MVA-NP+M1) is designed to boost preexisting T-cell responses in adults in order to elicit a cross-protective immune response. We examined the coadministration of HA protein formulations and candidate MVA-NP+M1 influenza vaccines in murine, avian, and swine models. Ab responses postimmunization were measured by ELISA and pseudotype neutralization assays. Here, we demonstrate that MVA-NP+M1 can act as an adjuvant enhancing Ab responses to HA while simultaneously inducing potent T-cell responses to conserved internal Ags. We show that this regimen leads to the induction of cytophilic Ab isotypes that are capable of inhibiting hemagglutination and in the context of H5 exhibit cross-clade neutralization. The simultaneous induction of T cells and Ab responses has the potential to improve seasonal vaccine performance and could be employed in pandemic situations.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Vacunas contra la Influenza/inmunología , Vacunas Virales/inmunología , Animales , Aves , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Glicoproteínas Hemaglutininas del Virus de la Influenza/inmunología , Virus de la Influenza A/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Nucleoproteínas/inmunología , Sus scrofa , Porcinos , Vacunas de ADN , Proteínas del Núcleo Viral/inmunología
5.
J Immunol ; 189(10): 4930-8, 2012 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-23066147

RESUMEN

The TLRs represent a family of pattern recognition receptors critical in the induction of vertebrate immune responses. Between 10 and 13 different TLR genes can be identified in each vertebrate species, with many represented as orthologous genes in different species. The agonist specificity of orthologous TLR is also highly conserved. In contrast, TLR15 can only be identified in avian and reptilian genomes, suggesting that this receptor arose ~320 million years ago after divergence of the bird/reptile and mammalian lineages. Transfection of a constitutively active form of chicken TLR15 led to NF-κB activation in HEK293 cells and induced cytokine mRNA upregulation in chicken cell lines. Full-length TLR15 mediated NF-κB induction in response to lysates from yeast, but not those derived from viral or bacterial pathogens, or a panel of well-characterized TLR agonists. TLR15 responses were induced by whole-cell lysates derived from Candida albicans, Saccharomyces cerevisiae, and Schizosaccharomyces pombe, but not zymosan preparations from S. cerevisiae. The ability of yeast lysate to activate TLR15-dependent NF-κB pathways (in transfection assays) or stimulate IL-1ß mRNA upregulation in chicken macrophages was abrogated by heat inactivation or pre-exposure of the lysate to PMSF. Identification of yeast as an agonist source for TLR15 provides a functional framework for consideration of this TLR within the context of pattern recognition receptor evolution and may impact on the development of novel adjuvants.


Asunto(s)
Antígenos Fúngicos/inmunología , Proteínas Aviares/inmunología , Aves/inmunología , Evolución Molecular , Lagartos/inmunología , Receptores Toll-Like/inmunología , Levaduras/inmunología , Animales , Antígenos Fúngicos/química , Proteínas Aviares/genética , Aves/genética , Células HEK293 , Humanos , Interleucina-1beta/genética , Interleucina-1beta/inmunología , Lagartos/genética , FN-kappa B/genética , FN-kappa B/inmunología , Transducción de Señal/fisiología , Especificidad de la Especie , Receptores Toll-Like/agonistas , Receptores Toll-Like/genética , Levaduras/química
6.
Sci Rep ; 14(1): 13549, 2024 06 12.
Artículo en Inglés | MEDLINE | ID: mdl-38866854

RESUMEN

Whilst. pharmacological therapies remain the cornerstone of pain management in chronic pain, factors including the current opioid epidemic have led to non-pharmacological techniques becoming a more attractive proposition. We explored the prevalence of medical device use and their treatment efficacy in non-cancer pain management. A systematic methodology was developed, peer reviewed and published in PROSPERO (CRD42021235384). Key words of medical device, pain management devices, chronic pain, lower back pain, back pain, leg pain and chronic pelvic pain using Science direct, PubMed, Web of Science, PROSPERO, MEDLINE, EMBASE, PorQuest and ClinicalTrials.gov. All clinical trials, epidemiology and mixed methods studies that reported the use of medical devices for non-cancer chronic pain management published between the 1st of January 1990 and the 30th of April 2022 were included. 13 studies were included in systematic review, of these 6 were used in the meta-analysis. Our meta-analysis for pain reduction showed that transcutaneous electrical nerve stimulation combined with instrument-assisted soft tissue mobilization treatment and pulsed electromagnetic therapy produced significant treatment on chronic lower back pain patients. Pooled evidence revealed the use of medical device related interventions resulted in 0.7 degree of pain reduction under a 0-10 scale. Significant improvement in disability scores, with a 7.44 degree reduction in disability level compared to a placebo using a 50 score range was also seen. Our analysis has shown that the optimal use of medical devices in a sustainable manner requires further research, needing larger cohort studies, greater gender parity, in a more diverse range of geographical locations.


Asunto(s)
Teorema de Bayes , Dolor Crónico , Manejo del Dolor , Humanos , Dolor Crónico/terapia , Manejo del Dolor/métodos , Dolor de la Región Lumbar/terapia , Estimulación Eléctrica Transcutánea del Nervio/métodos , Equipos y Suministros , Resultado del Tratamiento
7.
Sci Rep ; 14(1): 1621, 2024 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-38238384

RESUMEN

It is estimated 1.5 billion of the global population suffer from chronic pain with prevalence increasing with demographics including age. It is suggested long-term exposure to chronic could cause further health challenges reducing people's quality of life. Therefore, it is imperative to use effective treatment options. We explored the current pharmaceutical treatments available for chronic pain management to better understand drug efficacy and pain reduction. A systematic methodology was developed and published in PROSPERO (CRD42021235384). Keywords of opioids, acute pain, pain management, chronic pain, opiods, NSAIDs, and analgesics were used across PubMed, Science direct, ProQuest, Web of science, Ovid Psych INFO, PROSPERO, EBSCOhost, MEDLINE, ClinicalTrials.gov and EMBASE. All randomised controlled clinical trials (RCTs), epidemiology and mixed-methods studies published in English between the 1st of January 1990 and 30th of April 2022 were included. A total of 119 studies were included. The data was synthesised using a tri-partied statistical methodology of a meta-analysis (24), pairwise meta-analysis (24) and network meta-analysis (34). Mean, median, standard deviation and confidence intervals for various pain assessments were used as the main outcomes for pre-treatment pain scores at baseline, post-treatment pain scores and pain score changes of each group. Our meta-analysis revealed the significant reduction in chronic pain scores of patients taking NSAID versus non-steroidal opioid drugs was comparative to patients given placebo under a random effects model. Pooled evidence also indicated significant drug efficiency with Botulinum Toxin Type-A (BTX-A) and Ketamine. Chronic pain is a public health problem that requires far more effective pharmaceutical interventions with minimal better side-effect profiles which will aid to develop better clinical guidelines. The importance of understanding ubiquity of pain by clinicians, policy makers, researchers and academic scholars is vital to prevent social determinant which aggravates issue.


Asunto(s)
Dolor Crónico , Humanos , Dolor Crónico/tratamiento farmacológico , Dolor Crónico/inducido químicamente , Metaanálisis en Red , Calidad de Vida , Antiinflamatorios no Esteroideos/uso terapéutico , Preparaciones Farmacéuticas
8.
Physiol Genomics ; 45(14): 590-6, 2013 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-23695887

RESUMEN

This study addresses how depletion of human cardiac left ventricle (LV) mitochondrial DNA (mtDNA) and epigenetic nuclear DNA methylation promote cardiac dysfunction in human dilated cardiomyopathy (DCM) through regulation of pyrimidine nucleotide kinases. Samples of DCM LV and right ventricle (n = 18) were obtained fresh at heart transplant surgery. Parallel samples from nonfailing (NF) controls (n = 12) were from donor hearts found unsuitable for clinical use. We analyzed abundance of mtDNA and nuclear DNA (nDNA) using qPCR. LV mtDNA was depleted in DCM (50%, P < 0.05 each) compared with NF. No detectable change in RV mtDNA abundance occurred. DNA methylation and gene expression were determined using microarray analysis (GEO accession number: GSE43435). Fifty-seven gene promoters exhibited DNA hypermethylation or hypomethylation in DCM LVs. Among those, cytosolic thymidine kinase 1 (TK1) was hypermethylated. Expression arrays revealed decreased abundance of the TK1 mRNA transcript with no change in transcripts for other relevant thymidine metabolism enzymes. Quantitative immunoblots confirmed decreased TK1 polypeptide steady state abundance. TK1 activity remained unchanged in DCM samples while mitochondrial thymidine kinase (TK2) activity was significantly reduced. Compensatory TK activity was found in cardiac myocytes in the DCM LV. Diminished TK2 activity is mechanistically important to reduced mtDNA abundance and identified in DCM LV samples here. Epigenetic and genetic changes result in changes in mtDNA and in nucleotide substrates for mtDNA replication and underpin energy starvation in DCM.


Asunto(s)
Cardiomiopatías/genética , ADN Mitocondrial/genética , Epigénesis Genética/genética , Timidina Quinasa/genética , Western Blotting , Metilación de ADN/genética , Humanos , Técnicas In Vitro , Persona de Mediana Edad
9.
Physiol Genomics ; 45(14): 597-605, 2013 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-23695888

RESUMEN

Human dilated cardiomyopathy (DCM) is characterized by congestive heart failure and altered myocardial gene expression. Epigenetic changes, including DNA methylation, are implicated in the development of DCM but have not been studied extensively. Clinical human DCM and nonfailing control left ventricle samples were individually analyzed for DNA methylation and expressional changes. Expression microarrays were used to identify 393 overexpressed and 349 underexpressed genes in DCM (GEO accession number: GSE43435). Gene promoter microarrays were utilized for DNA methylation analysis, and the resulting data were analyzed by two different computational methods. In the first method, we utilized subtractive analysis of DNA methylation peak data to identify 158 gene promoters exhibiting DNA methylation changes that correlated with expression changes. In the second method, a two-stage approach combined a particle swarm optimization feature selection algorithm and a discriminant analysis via mixed integer programming classifier to identify differentially methylated gene promoters. This analysis identified 51 hypermethylated promoters and six hypomethylated promoters in DCM with 100% cross-validation accuracy in the group assignment. Generation of a composite list of genes identified by subtractive analysis and two-stage computation analysis revealed four genes that exhibited differential DNA methylation by both methods in addition to altered gene expression. Computationally identified genes (AURKB, BTNL9, CLDN5, and TK1) define a central set of differentially methylated gene promoters that are important in classifying DCM. These genes have no previously reported role in DCM. This study documents that rigorous computational analysis applied to microarray analysis of healthy and diseased human heart samples helps to define clinically relevant DNA methylation and expressional changes in DCM.


Asunto(s)
Cardiomiopatía Dilatada/genética , Metilación de ADN/genética , Perfilación de la Expresión Génica/métodos , Miocardio/metabolismo , Aurora Quinasa B/genética , Butirofilinas , Claudina-5/genética , Biología Computacional , Ventrículos Cardíacos/metabolismo , Humanos , Glicoproteínas de Membrana/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Regiones Promotoras Genéticas/genética , Timidina Quinasa/genética
10.
Lancet Infect Dis ; 23(8): 956-964, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37060917

RESUMEN

BACKGROUND: Rift Valley fever is a viral epidemic illness prevalent in Africa that can be fatal or result in debilitating sequelae in humans. No vaccines are available for human use. We aimed to evaluate the safety and immunogenicity of a non-replicating simian adenovirus-vectored Rift Valley fever (ChAdOx1 RVF) vaccine in humans. METHODS: We conducted a phase 1, first-in-human, open-label, dose-escalation trial in healthy adults aged 18-50 years at the Centre for Clinical Vaccinology and Tropical Medicine, Oxford, UK. Participants were required to have no serious comorbidities or previous history of receiving an adenovirus-based vaccine before enrolment. Participants were non-randomly allocated to receive a single ChAdOx1 RVF dose of either 5 × 109 virus particles (vp), 2·5 × 1010 vp, or 5 × 1010 vp administered intramuscularly into the deltoid of their non-dominant arm; enrolment was sequential and administration was staggered to allow for safety to be assessed before progression to the next dose. Primary outcome measures were assessment of adverse events and secondary outcome measures were Rift Valley fever neutralising antibody titres, Rift Valley fever GnGc-binding antibody titres (ELISA), and cellular response (ELISpot), analysed in all participants who received a vaccine. This trial is registered with ClinicalTrials.gov (NCT04754776). FINDINGS: Between June 11, 2021, and Jan 13, 2022, 15 volunteers received a single dose of either 5 × 109 vp (n=3), 2·5 × 1010 vp (n=6), or 5 × 1010 vp (n=6) ChAdOx1 RVF. Nine participants were female and six were male. 14 (93%) of 15 participants reported solicited local adverse reactions; injection-site pain was the most frequent (13 [87%] of 15). Ten (67%) of 15 participants (from the 2·5 × 1010 vp and 5 × 1010 vp groups only) reported systemic symptoms, which were mostly mild in intensity, the most common being headache (nine [60%] of 15) and fatigue (seven [47%]). All unsolicited adverse events reported within 28 days were either mild or moderate in severity; gastrointestinal symptoms were the most common reaction (at least possibly related to vaccination), occurring in four (27%) of 15 participants. Transient decreases in total white cell, lymphocyte, or neutrophil counts occurred at day 2 in some participants in the intermediate-dose and high-dose groups. Lymphopenia graded as severe occurred in two participants in the 5 × 1010 vp group at a single timepoint, but resolved at the subsequent follow-up visit. No serious adverse events occurred. Rift Valley fever neutralising antibodies were detectable across all dose groups, with all participants in the 5 × 1010 vp dose group having high neutralising antibody titres that peaked at day 28 after vaccination and persisted through the 3-month follow-up. High titres of binding IgG targeting Gc glycoprotein were detected whereas those targeting Gn were comparatively low. IFNγ cellular responses against Rift Valley fever Gn and Gc glycoproteins were observed in all participants except one in the 5 × 1010 vp dose group. These IFNγ responses peaked at 2 weeks after vaccination, were highest in the 5 × 1010 vp dose group, and tended to be more frequent against the Gn glycoprotein. INTERPRETATION: ChAdOx1 RVF was safe, well tolerated, and immunogenic when administered as a single dose in this study population. The data support further clinical development of ChAdOx1 RVF for human use. FUNDING: UK Department of Health and Social Care through the UK Vaccines Network, Oak Foundation, and the Wellcome Trust. TRANSLATION: For the Swahili translation of the abstract see Supplementary Materials section.


Asunto(s)
Fiebre del Valle del Rift , Vacunas Virales , Humanos , Adulto , Masculino , Femenino , Animales , Fiebre del Valle del Rift/prevención & control , Anticuerpos Neutralizantes , Glicoproteínas , Reino Unido , Inmunogenicidad Vacunal , Anticuerpos Antivirales , Método Doble Ciego
11.
Wellcome Open Res ; 8: 182, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38707489

RESUMEN

Background: There are limited data on the immunogenicity of coronavirus disease 2019 (COVID-19) vaccines in African populations. Here we report the immunogenicity and safety of the ChAdOx1 nCoV-19 (AZD1222) vaccine from a phase 1/2 single-blind, randomised, controlled trial among adults in Kenya conducted as part of the early studies assessing vaccine performance in different geographical settings to inform Emergency Use Authorisation. Methods: We recruited and randomly assigned (1:1) 400 healthy adults aged ≥18 years in Kenya to receive ChAdOx1 nCoV-19 or control rabies vaccine, each as a two-dose schedule with a 3-month interval. The co-primary outcomes were safety, and immunogenicity assessed using total IgG enzyme-linked immunosorbent assay (ELISA) against SARS-CoV-2 spike protein 28 days after the second vaccination. Results: Between 28 th October 2020 and 19 th August 2021, 400 participants were enrolled and assigned to receive ChAdOx1 nCoV-19 (n=200) or rabies vaccine (n=200). Local and systemic adverse events were self-limiting and mild or moderate in nature. Three serious adverse events were reported but these were deemed unrelated to vaccination. The geometric mean anti-spike IgG titres 28 days after second dose vaccination were higher in the ChAdOx1 group (2773 ELISA units [EU], 95% CI 2447, 3142) than in the rabies vaccine group (61 EU, 95% CI 45, 81) and persisted over the 12 months follow-up. We did not identify any symptomatic infections or hospital admissions with respiratory illness and so vaccine efficacy against clinically apparent infection could not be measured. Vaccine efficacy against asymptomatic SARS-CoV-2 infection was 38.4% (95% CI -26.8%, 70.1%; p=0.188). Conclusions: The safety, immunogenicity and efficacy against asymptomatic infection of ChAdOx1 nCoV-19 among Kenyan adults was similar to that observed elsewhere in the world, but efficacy against symptomatic infection or severe disease could not be measured in this cohort. Pan-African Clinical Trials Registration: PACTR202005681895696 (11/05/2020).

12.
Allergy Asthma Clin Immunol ; 8(1): 13, 2012 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-22863207

RESUMEN

BACKGROUND: Aerobic exercise appears to have clinical benefits for many asthmatics, yet a complete understanding of the mechanisms underlying these benefits has not been elucidated at this time. PURPOSE: The objective of this study was to determine feasibility for a larger, future study that will define the effect of aerobic exercise on cellular, molecular, and functional measures in adults with mild-moderate asthma. DESIGN: Recruited subjects were randomized into usual care (sedentary) or usual care with moderate intensity aerobic exercise treatment groups. SETTING / PARTICIPANTS: Nineteen adults with mild-moderate asthma but without a recent history of exercise were recruited at the UAB Lung Health Center, Birmingham, AL. INTERVENTION: The exercise group underwent a 12 week walking program exercising at 60 - 75% of maximum heart rate (HRmax). Subjects self-monitored HRmax levels using heart rate monitors; exercise diaries and recreation center sign-in logs were also used. MAIN OUTCOME MEASURES: Functional measures, including lung function and asthma control scores, were evaluated for all subjects at pre- and post-study time-points; fitness measures were also assessed for subjects in the exercise group. Peripheral blood and nasal lavage fluid were collected from all subjects at pre- and post-study visits in order to evaluate cellular and molecular measures, including cell differentials and eosinophilic cationic protein (ECP). RESULTS: Sixteen subjects completed the prescribed protocol. Results show that subjects randomized to the exercise group adhered well (80%) to the exercise prescription and exhibited a trend toward improved fitness levels upon study completion. Both groups exhibited improvements in ACQ scores. No changes were observed in lung function (FEV1, FEV1/FVC), cell differentials, or ECP between groups. CONCLUSIONS: Results indicate that a moderate intensity aerobic exercise training program may improve asthma control and fitness levels without causing asthma deterioration in adult asthmatics. As such, these findings demonstrate the feasibility of the study protocol in preparation for a larger, clinical trial that will elucidate the functional consequences of aerobic exercise on asthmatic cellular and molecular responses.

13.
Front Immunol ; 13: 1052297, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36685492

RESUMEN

Microbial colonisation is paramount to the normal development of the immune system, particularly at mucosal sites. However, the relationships between the microbiome and the adaptive immune repertoire have mostly been explored in rodents and humans. Here, we report a high-throughput sequencing analysis of the chicken TCRß repertoire and the influences of microbial colonisation on tissue-resident TCRß+ cells. The results reveal that the microbiome is an important driver of TCRß diversity in both intestinal tissues and the bursa of Fabricius, but not in the spleen. Of note, public TCRß sequences (shared across individuals) make a substantial contribution to the repertoire. Additionally, different tissues exhibit biases in terms of their V family and J gene usage, and these effects were influenced by the gut-associated microbiome. TCRß clonal expansions were identified in both colonised and germ-free birds, but differences between the groups were indicative of an influence of the microbiota. Together, these findings provide an insight into the avian adaptive immune system and the influence of the microbiota on the TCRß repertoire.


Asunto(s)
Pollos , Sistema Inmunológico , Humanos , Animales , Intestinos
14.
Mol Plant Pathol ; 22(6): 737-752, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33724663

RESUMEN

Phytophthora infestans is a destructive pathogen of potato and a model for investigations of oomycete biology. The successful application of a CRISPR gene editing system to P. infestans is so far unreported. We discovered that it is difficult to express CRISPR/Cas9 but not a catalytically inactive form in transformants, suggesting that the active nuclease is toxic. We were able to achieve editing with CRISPR/Cas12a using vectors in which the nuclease and its guide RNA were expressed from a single transcript. Using the elicitor gene Inf1 as a target, we observed editing of one or both alleles in up to 13% of transformants. Editing was more efficient when guide RNA processing relied on the Cas12a direct repeat instead of ribozyme sequences. INF1 protein was not made when both alleles were edited in the same transformant, but surprisingly also when only one allele was altered. We discovered that the isolate used for editing, 1306, exhibited monoallelic expression of Inf1 due to insertion of a copia-like element in the promoter of one allele. The element exhibits features of active retrotransposons, including a target site duplication, long terminal repeats, and an intact polyprotein reading frame. Editing occurred more often on the transcribed allele, presumably due to differences in chromatin structure. The Cas12a system not only provides a tool for modifying genes in P. infestans, but also for other members of the genus by expanding the number of editable sites. Our work also highlights a natural mechanism that remodels oomycete genomes.


Asunto(s)
Edición Génica , Phytophthora infestans/genética , Enfermedades de las Plantas/parasitología , Solanum tuberosum/parasitología , Alelos , Sistemas CRISPR-Cas , Cromatina/genética , Genómica , Phytophthora infestans/fisiología
15.
Integr Comp Biol ; 61(3): 969-980, 2021 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-34050739

RESUMEN

Engaging students in authentic research increases student knowledge, develops STEM skills, such as data analysis and scientific communication, and builds community. Creating authentic research opportunities in plant biology might be particularly crucial in addressing plant awareness disparity (PAD) (formerly known as plant blindness), producing graduates with botanical literacy, and preparing students for plant-focused careers. Our consortium created four CUREs (course-based undergraduate research experiences) focused on dual themes of plant biology and global change, designed to be utilized by early and late-career undergraduates across a variety of educational settings. We implemented these CURES for four semesters, in a total of 15 courses, at four institutions. Pre- and post-course assessments used the Affective Elements of Science Learning Questionnaire and parts of a "plant blindness" instrument to quantify changes in scientific self-efficacy, science values, scientific identity, and plant awareness or knowledge. The qualitative assessment also queried self-efficacy, science values, and scientific identity. Data revealed significant and positive shifts in awareness of and interest in plants across institutions. However, quantitative gains in self-efficacy and scientific identity were only found at two of four institutions tested. This project demonstrates that implementing plant CUREs can produce affective and cognitive gains across institutional types and course levels. Focusing on real-world research questions that capture students' imaginations and connect to their sense of place could create plant awareness while anchoring students in scientific identities. While simple interventions can alleviate PAD, implementing multiple CUREs per course, or focusing more on final CURE products, could promote larger and more consistent gains in student affect across institutions.


Asunto(s)
Biología/educación , Botánica/educación , Curriculum , Plantas , Estudiantes , Comunicación , Humanos , Investigación , Universidades
16.
Front Immunol ; 12: 763912, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34804053

RESUMEN

There is a critical need to develop superior influenza vaccines that provide broader protection. Influenza vaccines are traditionally tested in naive animals, although humans are exposed to influenza in the first years of their lives, but the impact of prior influenza exposure on vaccine immune responses has not been well studied. Pigs are an important natural host for influenza, are a source of pandemic viruses, and are an excellent model for human influenza. Here, we investigated the immunogenicity of the ChAdOx2 viral vectored vaccine, expressing influenza nucleoprotein, matrix protein 1, and neuraminidase in H1N1pdm09 pre-exposed pigs. We evaluated the importance of the route of administration by comparing intranasal, aerosol, and intramuscular immunizations. Aerosol delivery boosted the local lung T-cell and antibody responses, while intramuscular immunization boosted peripheral blood immunity. These results will inform how best to deliver vaccines in order to harness optimal protective immunity.


Asunto(s)
Anticuerpos Antivirales/sangre , Subtipo H1N1 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/inmunología , Proteínas de la Matriz Viral/inmunología , Adenoviridae/genética , Aerosoles , Animales , Citocinas/biosíntesis , Vacunas contra la Influenza/administración & dosificación , Neuraminidasa/inmunología , Proteínas de la Nucleocápside/inmunología , Porcinos , Vacunación , Esparcimiento de Virus
17.
J Biol Chem ; 284(52): 36191-36201, 2009 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-19840931

RESUMEN

Previous work from our laboratory has focused on mitochondrial DNA (mtDNA) repair and cellular viability. However, other events occur prior to the initiation of apoptosis in cells. Because of the importance of mtDNA in ATP production and of ATP in fuel cell cycle progression, we asked whether mtDNA damage was an upstream signal leading to cell cycle arrest. Using quantitative alkaline Southern blot technology, we found that exposure to menadione produced detectable mtDNA damage in HeLa cells that correlated with an S phase cell cycle arrest. To determine whether mtDNA damage was causatively linked to the observed cell cycle arrest, experiments were performed utilizing a MTS-hOGG1-Tat fusion protein to target the hOGG1 repair enzyme to mitochondria and enhance mtDNA repair. The results revealed that the transduction of MTS-hOGG1-Tat into HeLa cells alleviated the cell cycle block following an oxidative insult. Furthermore, mechanistic studies showed that Chk2 phosphorylation was enhanced following menadione exposure. Treatment of the HeLa cells with the hOGG1 fusion protein prior to menadione exposure resulted in an increase in the rate of Chk2 dephosphorylation. These results strongly support a direct link between mtDNA damage and cell cycle arrest.


Asunto(s)
Daño del ADN/fisiología , Reparación del ADN/fisiología , ADN Mitocondrial/metabolismo , Mitocondrias/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Fase S/fisiología , Adenosina Trifosfato/genética , Adenosina Trifosfato/metabolismo , Animales , Quinasa de Punto de Control 2 , Daño del ADN/efectos de los fármacos , ADN Glicosilasas/genética , ADN Glicosilasas/metabolismo , Reparación del ADN/efectos de los fármacos , ADN Mitocondrial/genética , Células HeLa , Humanos , Mitocondrias/genética , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/fisiología , Fosforilación/efectos de los fármacos , Fosforilación/fisiología , Proteínas Serina-Treonina Quinasas/genética , Ratas , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Fase S/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Vitamina K 3/farmacología , Vitaminas/farmacología
18.
Lancet Infect Dis ; 20(7): 816-826, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32325038

RESUMEN

BACKGROUND: Cases of Middle East respiratory syndrome coronavirus (MERS-CoV) infection continue to rise in the Arabian Peninsula 7 years after it was first described in Saudi Arabia. MERS-CoV poses a significant risk to public health security because of an absence of currently available effective countermeasures. We aimed to assess the safety and immunogenicity of the candidate simian adenovirus-vectored vaccine expressing the full-length spike surface glycoprotein, ChAdOx1 MERS, in humans. METHODS: This dose-escalation, open-label, non-randomised, uncontrolled, phase 1 trial was done at the Centre for Clinical Vaccinology and Tropical Medicine (Oxford, UK) and included healthy people aged 18-50 years with negative pre-vaccination tests for HIV antibodies, hepatitis B surface antigen, and hepatitis C antibodies (and a negative urinary pregnancy test for women). Participants received a single intramuscular injection of ChAdOx1 MERS at three different doses: the low-dose group received 5 × 109 viral particles, the intermediate-dose group received 2·5 × 1010 viral particles, and the high-dose group received 5 × 1010 viral particles. The primary objective was to assess safety and tolerability of ChAdOx1 MERS, measured by the occurrence of solicited, unsolicited, and serious adverse events after vaccination. The secondary objective was to assess the cellular and humoral immunogenicity of ChAdOx1 MERS, measured by interferon-γ-linked enzyme-linked immunospot, ELISA, and virus neutralising assays after vaccination. Participants were followed up for up to 12 months. This study is registered with ClinicalTrials.gov, NCT03399578. FINDINGS: Between March 14 and Aug 15, 2018, 24 participants were enrolled: six were assigned to the low-dose group, nine to the intermediate-dose group, and nine to the high-dose group. All participants were available for follow-up at 6 months, but five (one in the low-dose group, one in the intermediate-dose group, and three in the high-dose group) were lost to follow-up at 12 months. A single dose of ChAdOx1 MERS was safe at doses up to 5 × 1010 viral particles with no vaccine-related serious adverse events reported by 12 months. One serious adverse event reported was deemed to be not related to ChAdOx1 MERS. 92 (74% [95% CI 66-81]) of 124 solicited adverse events were mild, 31 (25% [18-33]) were moderate, and all were self-limiting. Unsolicited adverse events in the 28 days following vaccination considered to be possibly, probably, or definitely related to ChAdOx1 MERS were predominantly mild in nature and resolved within the follow-up period of 12 months. The proportion of moderate and severe adverse events was significantly higher in the high-dose group than in the intermediate-dose group (relative risk 5·83 [95% CI 2·11-17·42], p<0·0001) Laboratory adverse events considered to be at least possibly related to the study intervention were self-limiting and predominantly mild in severity. A significant increase from baseline in T-cell (p<0·003) and IgG (p<0·0001) responses to the MERS-CoV spike antigen was observed at all doses. Neutralising antibodies against live MERS-CoV were observed in four (44% [95% CI 19-73]) of nine participants in the high-dose group 28 days after vaccination, and 19 (79% [58-93]) of 24 participants had antibodies capable of neutralisation in a pseudotyped virus neutralisation assay. INTERPRETATION: ChAdOx1 MERS was safe and well tolerated at all tested doses. A single dose was able to elicit both humoral and cellular responses against MERS-CoV. The results of this first-in-human clinical trial support clinical development progression into field phase 1b and 2 trials. FUNDING: UK Department of Health and Social Care, using UK Aid funding, managed by the UK National Institute for Health Research.


Asunto(s)
Relación Dosis-Respuesta Inmunológica , Inmunogenicidad Vacunal , Coronavirus del Síndrome Respiratorio de Oriente Medio/inmunología , Vacunas Virales/administración & dosificación , Adulto , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales , Infecciones por Coronavirus/prevención & control , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Persona de Mediana Edad , Coronavirus del Síndrome Respiratorio de Oriente Medio/genética , Reino Unido , Vacunas de ADN , Adulto Joven
19.
Wound Repair Regen ; 16(5): 699-705, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19128265

RESUMEN

Scleroderma is a chronic disease characterized by excessive tissue fibrosis. Recent studies indicate that cultured dermal fibroblasts isolated from patients produce excessive amounts of collagen and other extracellular matrix components. In this study, we investigated the mechanism(s) of abnormal extracellular matrix accumulation in the scleroderma biopsies and the healing wounds of Tsk1/+ mice. Full-thickness excisional wounds were made in Tsk1/+ and wild-type mice and were subsequently harvested at days 7, 10, and 14 postinjury. The levels of pro-fibrotic cytokine, transforming growth factor were elevated in the wounds of Tsk1/+ mice. Interestingly, the levels of matrix metalloproteinase were significantly reduced in the granulation tissue of Tsk1/+ mice in comparison with wild-type. Furthermore, immunohistochemical analysis of the wounds indicated that the levels of gamma-glutamyl-epsilon-lysine cross-links were elevated in the granulation tissue of Tsk1/+ mice as well as the fibrotic lesions of scleroderma specimens. Collectively, these findings indicate that elevated collagen synthesis and decreased matrix metalloproteinase levels, in combination with increased isopeptide bond cross-links, contribute to abnormal collagen synthesis and assembly in granulation tissue of Tsk1/+ mice and the fibrotic lesions of scleroderma patients.


Asunto(s)
Esclerodermia Sistémica/patología , Piel/patología , Cicatrización de Heridas , Animales , Fibrosis , Humanos , Ratones , Péptidos/metabolismo , Esclerodermia Sistémica/metabolismo , Piel/metabolismo
20.
Physiol Biochem Zool ; 91(4): 987-1004, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29905500

RESUMEN

Wild-living animals are subject to weather variability that may cause the generation of reactive oxygen species, resulting in oxidative stress and tissue damage, potentially driving demographic responses. Our 3-yr field study investigated the effects of seasonal weather conditions on biomarkers for oxidative stress, oxidative damage, and antioxidant defense in the European badger (Meles meles). We found age class effects: cubs were more susceptible to oxidative stress and oxidative damage than adults, especially very young cubs in the spring, when they also exhibited lower antioxidant biomarkers than adults. Although previous studies have found that intermediate spring and summer rainfall and warmer temperatures favor cub survival, counterintuitively these conditions were associated with more severe oxidative damage. Oxidative damage was high in cubs even when antioxidant biomarkers were high. In contrast, adult responses accorded with previous survival analyses. Wetter spring and summer conditions were associated with higher oxidative damage, but they were also associated with higher antioxidant biomarkers. Autumnal weather did not vary substantially from normative values, and thus effects were muted. Winter carryover effects were partially evident, with drier and milder conditions associated with greater oxidative damage in the following spring but also with higher antioxidant capacity. Plausibly, warmer conditions promoted more badger activity, with associated metabolic costs at a time of year when food supply is limited. Modeling biomarkers against projected climate change scenarios predicted greater future risks of oxidative damage, although not necessarily exceeding antioxidant capacity. This interdisciplinary approach demonstrates that individual adaptive physiological responses are associated with variation in natural environmental conditions.


Asunto(s)
Antioxidantes/fisiología , Mustelidae/fisiología , Estrés Oxidativo/fisiología , Envejecimiento , Animales , Biomarcadores , Cambio Climático , Peroxidación de Lípido/fisiología , Longevidad , Mustelidae/sangre , Análisis de Componente Principal , Estaciones del Año , Factores de Tiempo , Tiempo (Meteorología)
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