Search results for "RHA"
showing 10 items of 1939 documents
Human milk and mucosal lacto- and galacto-N-biose synthesis by transgalactosylation and their prebiotic potential in Lactobacillus species.
2017
Lacto-N-biose (LNB) and galacto-N-biose (GNB) are major building blocks of free oligosaccharides and glycan moieties of glyco-complexes present in human milk and gastrointestinal mucosa. We have previously characterized the phospho-β-galactosidase GnbG from Lactobacillus casei BL23 that is involved in the metabolism of LNB and GNB. GnbG has been used here in transglycosylation reactions, and it showed the production of LNB and GNB with N-acetylglucosamine and N-acetylgalactosamine as acceptors, respectively. The reaction kinetics demonstrated that GnbG can convert 69 ± 4 and 71 ± 1 % of o-nitrophenyl-β-d-galactopyranoside into LNB and GNB, respectively. Those reactions were performed in a s…
Increased survival of honeybees in the laboratory after simultaneous exposure to low doses of pesticides and bacteria
2018
Recent studies of honeybees and bumblebees have examined combinatory effects of different stressors, as insect pollinators are naturally exposed to multiple stressors. At the same time the potential influences of simultaneously occurring agricultural agents on insect pollinator health remain largely unknown. Due to different farming methods, and the drift of applied agents and manure, pollinators are most probably exposed to insecticides but also bacteria from organic fertilizers at the same time. We orally exposed honeybee workers to sub-lethal doses of the insecticide thiacloprid and two strains of the bacterium Enterococcus faecalis, which can occur in manure from farming animals. Our re…
Dermal CD207-Negative Migratory Dendritic Cells Are Fully Competent to Prime Protective, Skin Homing Cytotoxic T-Lymphocyte Responses
2018
Dendritic cells (DCs) are important inducers and regulators of T-cell responses. They are able to activate and modulate the differentiation of CD4+ and CD8+ T cells. In the skin, there are at least five phenotypically distinct DC subpopulations that can be distinguished by differential expression of the cell surface markers CD207, CD103, and CD11b. Previous studies have suggested that dermal CD11b−CD207+ conventional type 1 DCs are indispensable for the priming of a skin homing cytotoxic T-lymphocyte response. However, conventional type 1 DCs are also the only skin DC subset capable of cross-presenting exogenous antigens on major histocompatibility complex class I. Thus, it remained unclear…
Langerhans Cells Suppress CD8+ T Cells In Situ during Mucocutaneous Acute Graft-Versus-Host Disease
2021
Acute graft-versus-host disease (aGVHD) induced by allogenic hematopoietic stem cell transplantation is an immunological disorder in which donor lymphocytes attack recipient organs. It has been proven that recipient nonhematopoietic tissue cells, such as keratinocytes, are sufficient as immunological targets for allogenic donor T cells, whereas Langerhans cells (LCs) are potent professional hematopoietic antigen-presenting cells existing in the target epidermis and eliminated during the early phase of mucocutaneous aGVHD. Moreover, LCs have been reported to negatively regulate various types of immune responses. Here, we present data showing that initial depletion of recipient LCs exacerbate…
Selective AhR knockout in langerin-expressing cells abates Langerhans cells and polarizes Th2/Tr1 in epicutaneous protein sensitization
2020
The aryl hydrocarbon receptor (AhR) represents an environmental sensor regulating immune responses. In the skin, AhR is expressed in several cell types, including keratinocytes, epidermal Langerhans cells (LC), and dermal dendritic cells (DC). The mechanisms how AhR activates or inhibits cutaneous immune responses remain controversial, owing to differences in the cell-specific functions of AhR and the different activating ligands. Therefore, we sought to investigate the role of AhR in LC and langerin(+) and negative DC in the skin. To this aim, we generated Langerin-specific and CD11c-specific knockout ((−/−)) mice lacking AhR, respectively, in LC and Langerin(+) dermal DC and in all CD11c(…
Refining prediction of survival after TIPS with the novel Freiburg index of post-TIPS survival.
2021
Background & Aims Transjugular intrahepatic portosystemic shunt (TIPS) implantation is an effective and safe treatment for complications of portal hypertension. Survival prediction is important in these patients as they constitute a high-risk population. Therefore, the aim of our study was to develop an alternative prognostic model for accurate survival prediction after planned TIPS implantation. Methods A total of 1,871 patients with de novo TIPS implantation for ascites or secondary prophylaxis of variceal bleeding were recruited retrospectively. The study cohort was divided into a training set (80% of study patients; n = 1,496) and a validation set (20% of study patients; n = 375). Furth…
3d collagen hydrogel promotes in vitro langerhans islets vascularization through ad-mvfs angiogenic activity
2021
Adipose derived microvascular fragments (ad-MVFs) consist of effective vascularization units able to reassemble into efficient microvascular networks. Because of their content in stem cells and related angiogenic activity, ad-MVFs represent an interesting tool for applications in regenerative medicine. Here we show that gentle dissociation of rat adipose tissue provides a mixture of ad-MVFs with a length distribution ranging from 33–955 μm that are able to maintain their original morphology. The isolated units of ad-MVFs that resulted were able to activate transcriptional switching toward angiogenesis, forming tubes, branches, and entire capillary networks when cultured in 3D collagen type-…
Interferon-γ-Driven iNOS: A Molecular Pathway to Terminal Shock in Arenavirus Hemorrhagic Fever
2017
Arenaviruses such as Lassa virus (LASV) cause hemorrhagic fever. Terminal shock is associated with a systemic cytokine storm, but the mechanisms are ill defined. Here we used HLA-A2-expressing mice infected with a monkey-pathogenic strain of lymphocytic choriomeningitis virus (LCMV-WE), a close relative of LASV, to investigate the pathophysiology of arenavirus hemorrhagic fever (AHF). AHF manifested as pleural effusions, edematous skin swelling, and serum albumin loss, culminating in hypovolemic shock. A characteristic cytokine storm included numerous pro-inflammatory cytokines and nitric oxide (NO) metabolites. Edema formation and terminal shock were abrogated in mice lacking inducible nit…
Microevolution of bank voles (Myodes glareolus) at neutral and immune-related genes during multiannual dynamic cycles: consequences for Puumala hanta…
2017
ABSTRACTUnderstanding how host dynamics, including variations of population size and dispersal, may affect the epidemiology of infectious diseases through ecological and evolutionary processes is an active research area. Here we focus on a bank vole (Myodes glareolus) metapopulation surveyed in Finland between 2005 and 2009. Bank vole is the reservoir of Puumala hantavirus (PUUV), the agent of nephropathia epidemica (NE, a mild form of hemorrhagic fever with renal symptom) in humans.M glareoluspopulations experience multiannual density fluctuations that may influence the level of genetic diversity maintained in bank voles, PUUV prevalence and NE occurrence. We examine bank vole metapopulati…
miRNA92a targets KLF2 and the phosphatase PTEN signaling to promote human T follicular helper precursors in T1D islet autoimmunity.
2016
Aberrant immune activation mediated by T effector cell populations is pivotal in the onset of autoimmunity in type 1 diabetes (T1D). T follicular helper (TFH) cells are essential in the induction of high-affinity antibodies, and their precursor memory compartment circulates in the blood. The role of TFH precursors in the onset of islet autoimmunity and signaling pathways regulating their differentiation is incompletely understood. Here, we provide direct evidence that during onset of islet autoimmunity, the insulin-specific target T-cell population is enriched with a C-X-C chemokine receptor type 5 (CXCR5)(+)CD4(+) TFH precursor phenotype. During onset of islet autoimmunity, the frequency o…