Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
365
result(s) for
"Garssen, Johan"
Sort by:
Classification and specific primer design for accurate detection of SARS-CoV-2 using deep learning
by
Mulders, Daphne
,
Mendoza-Maldonado, Lucero
,
Kraneveld, Aletta
in
631/114/1386
,
639/705/117
,
692/699/255/2514
2021
In this paper, deep learning is coupled with explainable artificial intelligence techniques for the discovery of representative genomic sequences in SARS-CoV-2. A convolutional neural network classifier is first trained on 553 sequences from the National Genomics Data Center repository, separating the genome of different virus strains from the Coronavirus family with 98.73% accuracy. The network’s behavior is then analyzed, to discover sequences used by the model to identify SARS-CoV-2, ultimately uncovering sequences exclusive to it. The discovered sequences are validated on samples from the National Center for Biotechnology Information and Global Initiative on Sharing All Influenza Data repositories, and are proven to be able to separate SARS-CoV-2 from different virus strains with near-perfect accuracy. Next, one of the sequences is selected to generate a primer set, and tested against other state-of-the-art primer sets, obtaining competitive results. Finally, the primer is synthesized and tested on patient samples (n = 6 previously tested positive), delivering a sensitivity similar to routine diagnostic methods, and 100% specificity. The proposed methodology has a substantial added value over existing methods, as it is able to both automatically identify promising primer sets for a virus from a limited amount of data, and deliver effective results in a minimal amount of time. Considering the possibility of future pandemics, these characteristics are invaluable to promptly create specific detection methods for diagnostics.
Journal Article
The Interplay between the Gut Microbiome and the Immune System in the Context of Infectious Diseases throughout Life and the Role of Nutrition in Optimizing Treatment Strategies
2021
Infectious diseases and infections remain a leading cause of death in low-income countries and a major risk to vulnerable groups, such as infants and the elderly. The immune system plays a crucial role in the susceptibility, persistence, and clearance of these infections. With 70–80% of immune cells being present in the gut, there is an intricate interplay between the intestinal microbiota, the intestinal epithelial layer, and the local mucosal immune system. In addition to the local mucosal immune responses in the gut, it is increasingly recognized that the gut microbiome also affects systemic immunity. Clinicians are more and more using the increased knowledge about these complex interactions between the immune system, the gut microbiome, and human pathogens. The now well-recognized impact of nutrition on the composition of the gut microbiota and the immune system elucidates the role nutrition can play in improving health. This review describes the mechanisms involved in maintaining the intricate balance between the microbiota, gut health, the local immune response, and systemic immunity, linking this to infectious diseases throughout life, and highlights the impact of nutrition in infectious disease prevention and treatment.
Journal Article
An evaluation of the inhibitory effects against rotavirus infection of edible plant extracts
by
Knipping, Karen
,
Garssen, Johan
,
van’t Land, Belinda
in
Antiviral activity
,
Antiviral agents
,
Antiviral Agents - pharmacology
2012
Background
Rotaviruses are the single most important cause of severe diarrhea in young children worldwide. The developments of specific, potent and accessible antiviral treatments that restrain rotavirus infection remain important to control rotavirus disease.
Methods
150 plant extracts with nutritional applications were screened
in vitro
on MA-104 cells for their antiviral activity against rhesus rotavirus (RRV). One extract (
Aspalathus linearis
(Burm.f.) R.Dahlgren) was also tested for its effect on the loss of transepithelial resistance (TER) of Caco-2 cells caused by simian rotavirus (SA-11) infection.
Results
Aqueous extracts of
Nelumbo nucifera
Gaertn. fruit,
Urtica dioica
L. root,
Aspalathus linearis
(Burm.f.) R.Dahlgren leaves,
Glycyrrhiza glabra
L. root and
Olea europaea
L. leaves were found to have strong significant antiviral activity with a 50% inhibitory concentration (IC50) < 300 μg/ml. The pure compound 18ß-glycyrrhetinic acid from
Glycyrrhiza glabra
was found to have the strongest antiviral activity (IC50 46 μM), followed by luteolin and vitexin from
Aspalathus linearis
(IC50 respectively 116 μM and 129 μM) and apigenin-7-O-glucoside from
Melissa officinalis
(IC50 150 μM). A combination of
Glycyrrhiza glabra
L. +
Nelumbo nucifera
Gaertn. and
Urtica dioica L.
+
Nelumbo nucifera
Gaertn. showed synergy in their anti-viral activities.
Aspalathus linearis
(Burm.f.) R.Dahlgren showed no positive effect on the maintenance of the TER.
Conclusions
These results indicate that nutritional intervention with extracts of
Nelumbo nucifera
Gaertn.,
Aspalathus linearis
(Burm.f.) R.Dahlgren,
Urtica dioica
L.,
Glycyrrhiza glabra
L. and
Olea europaea
L. might be useful in the treatment of diarrhea caused by rotavirus infection.
Journal Article
Maternal Cigarette Smoke Exposure Does Not Impair Influenza Vaccine Responsiveness in Murine Offspring
by
Braber, Saskia
,
Dehghani, Ali
,
Garssen, Johan
in
Air pollution
,
Breastfeeding & lactation
,
Carbon monoxide
2025
Background/Objectives: Environmental pollutants can profoundly affect immune development, yet their impact on offspring vaccine responsiveness remains poorly understood. To address this, we investigated the impact of maternal cigarette smoke (CS) exposure, a major contributor to household air pollution, on influenza vaccine responsiveness in offspring. Methods: Pregnant dams were exposed to CS or air during gestation and lactation. Two weeks post-weaning, offspring received two influenza vaccinations. After the booster vaccination, vaccine-specific delayed-type hypersensitivity (DTH), serum immunoglobulins, and splenic T cells were analyzed. Results: Vaccinated offspring exhibited robust DTH responses and comparable levels of vaccine-specific IgG1 and IgG2a, regardless of maternal exposure. Importantly, maternal CS exposure did not affect splenic Th1 cell frequency in vaccinated offspring but increased the frequency of activated Th2 cells. Conclusions: In conclusion, immune development was affected by enhanced Th2 activation, but vaccine efficacy was not impaired. These findings suggest that, under the current conditions of CS exposure (duration, route, and timing) and influenza vaccine dose, vaccine-induced immunity may exhibit resilience even in the presence of environmental immune modulators such as maternal CS exposure. However, these unexpected results highlight the need for further investigation into the broader health implications of maternal pollutant exposure, particularly considering how exposure timing, type, and route, as well as vaccine characteristics, may influence immune development and responsiveness. A deeper understanding of these factors is essential to fully elucidating the clinical relevance of maternal pollutant exposure on childhood vaccine efficacy.
Journal Article
Molecular Insights into the Mechanism of Necroptosis: The Necrosome as a Potential Therapeutic Target
2019
Necroptosis, or regulated necrosis, is an important type of programmed cell death in addition to apoptosis. Necroptosis induction leads to cell membrane disruption, inflammation and vascularization. It plays important roles in various pathological processes, including neurodegeneration, inflammatory diseases, multiple cancers, and kidney injury. The molecular regulation of necroptotic pathway has been intensively studied in recent years. Necroptosis can be triggered by multiple stimuli and this pathway is regulated through activation of receptor-interacting protein kinase 1 (RIPK1), RIPK3 and pseudokinase mixed lineage kinase domain-like (MLKL). A better understanding of the mechanism of regulation of necroptosis will further aid to the development of novel drugs for necroptosis-associated human diseases. In this review, we focus on new insights in the regulatory machinery of necroptosis. We further discuss the role of necroptosis in different pathologies, its potential as a therapeutic target and the current status of clinical development of drugs interfering in the necroptotic pathway.
Journal Article
Differences in Susceptibility to Heat Stress along the Chicken Intestine and the Protective Effects of Galacto-Oligosaccharides
by
Braber, Saskia
,
Garssen, Johan
,
Varasteh, Soheil
in
Adherens Junctions - drug effects
,
Adherens Junctions - metabolism
,
Ambient temperature
2015
High ambient temperatures negatively affect the human well-being as well as animal welfare and production. The gastrointestinal tract is predominantly responsive to heat stress. The currently available information about the multifaceted response to heat stress within different parts of the intestine is limited, especially in avian species. Hence, this study aims to evaluate the heat stress-induced sequence of events in the intestines of chickens. Furthermore, the gut health-promoting effect of dietary galacto-oligosaccharides (GOS) was investigated in these heat stress-exposed chickens. Chickens were fed a control diet or diet supplemented with 1% or 2.5% GOS (6 days) prior to and during a temperature challenge for 5 days (38-39°C, 8h per day). The parameters measured in different parts of the intestines included the genes (qPCR) HSF1, HSF3, HSP70, HSP90, E-cadherin, claudin-1, claudin-5, ZO-1, occludin, TLR-2, TLR-4, IL-6, IL-8, HO-1, HIF-1α) and their associated proteins HSP70, HSP90 and pan-cadherin (western blots). In addition, IL-6 and IL-8 plasma concentrations were measured by ELISA. In the jejunum, HSF3, HSP70, HSP90, E-cadherin, claudin-5, ZO-1, TLR-4, IL-6 and IL-8 mRNA expression and HSP70 protein expression were increased after heat stress exposure and a more pronounced increase in gene expression was observed in ileum after heat stress exposure, and in addition HSF1, claudin-1 and HIF-1α mRNA levels were upregulated. Furthermore, the IL-8 plasma levels were decreased in chickens exposed to heat stress. Interestingly, the heat stress-related effects in the jejunum were prevented in chickens fed a GOS diet, while dietary GOS did not alter these effects in ileum. In conclusion, our results demonstrate the differences in susceptibility to heat stress along the intestine, where the most obvious modification in gene expression is observed in ileum, while dietary GOS only prevent the heat stress-related changes in jejunum.
Journal Article
Beyond Heat Stress: Intestinal Integrity Disruption and Mechanism-Based Intervention Strategies
2020
The current climate changes have increased the prevalence and intensity of heat stress (HS) conditions. One of the initial consequences of HS is the impairment of the intestinal epithelial barrier integrity due to hyperthermia and hypoxia following blood repartition, which often results in a leaky gut followed by penetration and transfer of luminal antigens, endotoxins, and pathogenic bacteria. Under extreme conditions, HS may culminate in the onset of “heat stroke”, a potential lethal condition if remaining untreated. HS-induced alterations of the gastrointestinal epithelium, which is associated with a leaky gut, are due to cellular oxidative stress, disruption of intestinal integrity, and increased production of pro-inflammatory cytokines. This review summarizes the possible resilience mechanisms based on in vitro and in vivo data and the potential interventions with a group of nutritional supplements, which may increase the resilience to HS-induced intestinal integrity disruption and maintain intestinal homeostasis.
Journal Article
Immunometabolic factors in adolescent chronic disease are associated with Th1 skewing of invariant Natural Killer T cells
by
van der Ent, Cornelis K.
,
van’t Land, Belinda
,
Vastert, Bas
in
631/250/2152/1566/1618
,
631/250/256/2515
,
692/4023/1670/427/1304
2021
Invariant Natural Killer T (iNKT) cells respond to the ligation of lipid antigen-CD1d complexes via their T-cell receptor and are implicated in various immunometabolic diseases. We considered that immunometabolic factors might affect iNKT cell function. To this end, we investigated iNKT cell phenotype and function in a cohort of adolescents with chronic disease and immunometabolic abnormalities. We analyzed peripheral blood iNKT cells of adolescents with cystic fibrosis (CF, n = 24), corrected coarctation of the aorta (CoA, n = 25), juvenile idiopathic arthritis (JIA, n = 20), obesity (OB, n = 20), and corrected atrial septal defect (ASD, n = 25) as controls. To study transcriptional differences, we performed RNA sequencing on a subset of obese patients and controls. Finally, we performed standardized co-culture experiments using patient plasma, to investigate the effect of plasma factors on iNKT cell function. We found comparable iNKT cell numbers across patient groups, except for reduced iNKT cell numbers in JIA patients. Upon
ex-vivo
activation, we observed enhanced IFN-γ/IL-4 cytokine ratios in iNKT cells of obese adolescents versus controls. The Th1-skewed iNKT cell cytokine profile of obese adolescents was not explained by a distinct transcriptional profile of the iNKT cells. Co-culture experiments with patient plasma revealed that across all patient groups, obesity-associated plasma factors including LDL-cholesterol, leptin, and fatty-acid binding protein 4 (FABP4) coincided with higher IFN-γ production, whereas high HDL-cholesterol and insulin sensitivity (QUICKI) coincided with higher IL-4 production. LDL and HDL supplementation in co-culture studies confirmed the effects of lipoproteins on iNKT cell cytokine production. These results suggest that circulating immunometabolic factors such as lipoproteins may be involved in Th1 skewing of the iNKT cell cytokine response in immunometabolic disease.
Journal Article
Role of TLR4 in the gut-brain axis in Parkinson’s disease: a translational study from men to mice
2019
ObjectiveRecent evidence suggesting an important role of gut-derived inflammation in brain disorders has opened up new directions to explore the possible role of the gut-brain axis in neurodegenerative diseases. Given the prominence of dysbiosis and colonic dysfunction in patients with Parkinson’s disease (PD), we propose that toll-like receptor 4 (TLR4)-mediated intestinal dysfunction could contribute to intestinal and central inflammation in PD-related neurodegeneration.DesignTo test this hypothesis we performed studies in both human tissue and a murine model of PD. Inflammation, immune activation and microbiota composition were measured in colonic samples from subjects with PD and healthy controls subjects and rotenone or vehicle-treated mice. To further assess the role of the TLR4 signalling in PD-induced neuroinflammation, we used TLR4-knockout (KO) mice in conjunction with oral rotenone administration to model PD.ResultsPatients with PD have intestinal barrier disruption, enhanced markers of microbial translocation and higher pro-inflammatory gene profiles in the colonic biopsy samples compared with controls. In this regard, we found increased expression of the bacterial endotoxin-specific ligand TLR4, CD3+ T cells, cytokine expression in colonic biopsies, dysbiosis characterised by a decrease abundance of SCFA-producing colonic bacteria in subjects with PD. Rotenone treatment in TLR4-KO mice revealed less intestinal inflammation, intestinal and motor dysfunction, neuroinflammation and neurodegeneration, relative to rotenone-treated wild-type animals despite the presence of dysbiotic microbiota in TLR4-KO mice.ConclusionTaken together, these studies suggest that TLR4-mediated inflammation plays an important role in intestinal and/or brain inflammation, which may be one of the key factors leading to neurodegeneration in PD.
Journal Article
TLR9 and COVID-19: A Multidisciplinary Theory of a Multifaceted Therapeutic Target
2021
By mapping the clinical pathophysiology of the novel coronavirus disease 2019 (COVID-19) against insights from virology, immunology, genomics, epidemiology and pharmacology, it is here proposed that the pathogen recognition receptor called toll like receptor 9 (TLR9) might have a pivotal role in the pathogenesis of COVID-19. Severe Acute Respiratory Syndrome Coronavirus 2, is causing the greatest global social and economic disruption since world war II. Lack of a vaccine, lack of successful treatment and limitations of the healthcare workforce and resources needed to safeguard patients with severe COVID-19 on the edge of life, demands radical preventive measures. It is urgently needed to identify biomarkers and drug candidates so that vulnerable individuals can be recognized early and severe multi-organ complications can be prevented or dampened. The TLR9 COVID-19 hypothesis describes a mechanism of action that could explain a wide spectrum of manifestations observed in patients with severe COVID-19. The introduced hypothesis proposes biomarkers for identification of vulnerable individuals and positions TLR9 as a promising multifaceted intervention target for prevention and/or treatment of COVID-19. TLR9 agonists might have value as prophylactic vaccine adjuvants and therapeutic immune stimulators at the early onset of disease. Additionally, in this current manuscript it is proposed for the first time that TLR9 could be considered as a target of “inhibition” aimed to dampen hyperinflammation and thrombotic complications in vulnerable patients that are at risk of developing late stages of COVID-19. The readily availability of TLR9 modulating drug candidates that have reached clinical testing for other disorders could favor a fast track development scenario, an important advantage under the current high unmet medical need circumstances regarding COVID-19.
Journal Article