Search results for "Immunologic"
showing 10 items of 1115 documents
Imiquimod-Induced Psoriasis in Mice Depends on the IL-17 Signaling of Keratinocytes
2018
The pathology of psoriasis strongly depends on IL-17A. Monoclonal antibodies blocking either the cytokine or its receptor are among the most efficient treatments for psoriatic patients. Keratinocytes can be activated upon exposure to IL-17A and tumor necrosis factor-α and secrete secondary cytokines and chemokines in the inflamed skin. In psoriasis and its imiquimod-induced mouse model, a strong skin infiltration of neutrophils and inflammatory monocytes can be observed. However, to date, it is not clear how exactly those cellular populations are attracted to the skin and how they contribute to the pathogenesis of the disease. To define the crucial cell type responding to IL-17 and initiati…
Co-occurrence of resonant activation and noise-enhanced stability in a model of cancer growth in the presence of immune response.
2006
We investigate a stochastic version of a simple enzymatic reaction which follows the generic Michaelis-Menten kinetics. At sufficiently high concentrations of reacting species, the molecular fluctuations can be approximated as a realization of a Brownian dynamics for which the model reaction kinetics takes on the form of a stochastic differential equation. After eliminating a fast kinetics, the model can be rephrased into a form of a one-dimensional overdamped Langevin equation. We discuss physical aspects of environmental noises acting in such a reduced system, pointing out the possibility of coexistence of dynamical regimes where noise-enhanced stability and resonant activation phenomena …
Contact sensitivity as a model for T-cell activation in skin.
1995
Contact sensitivity has served as a useful model for the primary activation of T cells in skin and skin-associated lymphoid tissue. We have been interested in the early signals necessary for the induction of an allergen-specific T-cell response, as well as the factors controlling the intensity and extent of such an immune reaction. Because cytokines qualified as possible candidate molecules involved in directing primary immune responses in skin, we studied the early changes in the cytokine pattern of the epidermis. Apart from defining a cytokine pattern specifically induced only after application of allergen, we also identified Langerhans-cell-derived interleukin (IL)-1β as the first cytoki…
Transmission modes affect the population structure of potato virus Y in potato.
2020
Transmission is a crucial part of a viral life cycle and transmission mode can have an important impact on virus biology. It was demonstrated that transmission mode can influence the virulence and evolution of a virus; however, few empirical data are available to describe the direct underlying changes in virus population structure dynamics within the host. Potato virus Y (PVY) is an RNA virus and one of the most damaging pathogens of potato. It comprises several genetically variable strains that are transmitted between plants via different transmission modes. To investigate how transmission modes affect the within-plant viral population structure, we have used a deep sequencing approach to …
Physical fitness, hormonal, and immunological responses during prolonged military field training
2018
Physical fitness is crucial to warfighters’ performance in the battlefield. Previous studies have shown negative changes in their hormonal and neuromuscular responses induced by military field training (MFT). The purpose of this study was to investigate the changes in hormonal and immunological values and body composition during a prolonged MFT and to find out how warfighters’ physical condition influences these changes. Conscripts (n = 49, age 20 1 years, height 179 9 cm, body mass 73.8 7.8 kg, fat 12.6 3.7% and BMI 23 kg/m²) were measured before, during, after MFT, and after a 4-day recovery period. Serum insulin-like growth factor-1 (IGF-1), tumor necrosis factor alpha (TNF-a), interleuk…
Role of adipokines signaling in the modulation of T cells function
2013
The field that links immunity and metabolism is rapidly expanding. Apparently non-immunological disorders such as obesity and type 2 diabetes have been linked to immune dysregulation, suggesting that metabolic alterations can be induced by or be consequence of an altered self-immune tolerance. In this context, adipose tissue produces and releases a variety of pro-inflammatory and anti-inflammatory factors, termed "adipokines," which can be considered as the bridge between obesity-related exogenous factors, such as nutrition and lifestyle, and the molecular events leading to metabolic syndrome, inflammatory, and/or autoimmune conditions. In obesity, increased production of most adipokines im…
Decreased release of histamine and sulfidoleukotrienes by human peripheral blood leukocytes after wasp venom immunotherapy is partially due to induct…
1999
Abstract Background: Recent studies provide evidence that venom immunotherapy (VIT) alters the pattern of cytokine production by inducing an allergen-specific T-cell shift in cytokine expression from T H2 (IL-4, IL-5) to T H1 (IFN-γ) cytokines and also inducing the production of IL-10. Objective: This study was carried out to analyze whether these changes in cytokine production of T cells already observed 1 week after the initiation of VIT in subjects with wasp venom allergy also influence the reactivity of effector cells, such as mast cells and basophils. Methods: All subjects included in this study had a history of severe systemic allergic reactions to wasp stings and positive skin test r…
Adjuvant effects of aluminium hydroxide-adsorbed allergens and allergoids – differences in vivo and in vitro
2014
Summary Allergen-specific immunotherapy (SIT) is a clinically effective therapy for immunoglobulin (Ig)E-mediated allergic diseases. To reduce the risk of IgE-mediated side effects, chemically modified allergoids have been introduced. Furthermore, adsorbance of allergens to aluminium hydroxide (alum) is widely used to enhance the immune response. The mechanisms behind the adjuvant effect of alum are still not completely understood. In the present study we analysed the effects of alum-adsorbed allergens and allergoids on their immunogenicity in vitro and in vivo and their ability to activate basophils of allergic donors. Human monocyte derived dendritic cells (DC) were incubated with native …
eNOS S-nitrosylates β-actin on Cys374 and regulates PKC-θ at the immune synapse by impairing actin binding to profilin-1.
2017
The actin cytoskeleton coordinates the organization of signaling microclusters at the immune synapse (IS); however, the mechanisms involved remain poorly understood. We show here that nitric oxide (NO) generated by endothelial nitric oxide synthase (eNOS) controls the coalescence of protein kinase C-¿ (PKC-¿) at the central supramolecular activation cluster (c-SMAC) of the IS. eNOS translocated with the Golgi to the IS and partially colocalized with F-actin around the c-SMAC. This resulted in reduced actin polymerization and centripetal retrograde flow of ß-actin and PKC-¿ from the lamellipodium-like distal (d)-SMAC, promoting PKC-¿ activation. Furthermore, eNOS-derived NO S-nitrosylated ß-…
Gram-positive bacteria on grass pollen exhibit adjuvant activity inducing inflammatory T cell responses.
2011
BACKGROUND: Recently, it has been established that pollen grains contain Th2-enhancing activities besides allergens. OBJECTIVE: The aim of this study was to analyse whether pollen carry additional adjuvant factors like microbes and what immunological effects they may exert. METHODS: Timothy pollen grains were collected and disseminated on agar plates, and the growing microorganisms were cultivated and defined. Furthermore, the immunologic effects of microbial products on DC and T cell responses were analysed. RESULTS: A complex mixture of bacteria and moulds was detected on grass pollen. Besides Gram-negative bacteria that are known to favour Th1-directed immune responses, moulds were ident…