Search results for "Immune system"

Condition dependence of pheromones and immune function in the grain beetleTenebrio molitor

2003

Summary 1. Pheromones are chemical signals that function not only as mate attractors, but may also relay important information to prospective mates. In order for the information to be reliable, the signal must be costly to produce and this is likely to result in condition dependent expression of the signal. 2. We present results from two experiments on the grain beetle Tenebrio molitor examining phenotypic condition dependence of pheromones and patterns of female preference for pheromones. We also analysed condition dependence of two measures of immunocompetence: encapsulation response and phenoloxidase activity. 3. By manipulating the nutritional condition of the males we found that the at…

UVB light attenuates the systemic immune response in CNS autoimmunity

2014

An immune system model in discrete time based on the analogy with the central nervous system

1988

Jerne's model for the immune system formulated in terms of a neural network recently proposed by Weisbuch and Atlan is generalized to interactions with continuous coupling coefficients. It is shown that even the extended model can be solved analytically without the aid of computer simulations and exhibits one additional attractor, which corresponds to a configuration with high concentrations of active killer cells eventually causing death of the organism.

Viral evolution and Immune responses

2019

Antiviral responses are activated rapidly after viral infection in order to control and prevent dissemination of the virus. Different pathways are activated in the immune system, including innate and adaptive responses. On the other hand, viruses have evolved specifi c strategies to evade these responses. Due to the high viral evolutionary rates, escape variants can emerge and spread fast in the population. The co-evolution between viruses and their host is a constant arms race, and is of special interest to understand the viral escape mechanisms that may guide the future development of antiviral treatments and vaccines.

2004

Autoimmune inflammation, such as in rheumatoid arthritis, is characterized by activated Th1 cells without sufficient Th2 differentiation that might downmodulate the chronic immune response. Delineation of the mechanisms that control T-cell differentiation is therefore of major importance for the understanding of the pathogenesis of autoimmune diseases. The transcription factor GATA-3 has been implicated in regulating Th2 cell differentiation in murine T cells in vitro, but its role in vivo and, in particular, in human T-cell differentiation is currently unknown. To dissect the role of GATA-3 in human T-cell differentiation and T-cell-mediated effector functions, we used the unique opportuni…

Dendritic cells and the handling of antigen

2003

Dendritic cells (DC) are a sparsely distributed, migratory group of bone marrow-derived leucocytes that are specialized for the uptake, transport, processing and presentation of antigens to T cells [1,2]. At an immature stage of development DC are considered as the first-line sentinels in immune surveillance of peripheral tissues, including epithelia of the skin and mucosal surfaces, where they sample continuously the antigenic local microenvironment by uptake of self- and exogenous antigen via macropinocytosis/endocytosis [3,4]. The efficiency of DC to initiate an immune response against infectious disease is due to their constant trafficking between peripheral tissues and draining lymph n…

WITHDRAWN: Systems Biology and Immune Aging

2014

The Publisher regrets that this article is an accidental duplication of anarticle that has already been published, http://dx.doi.org/10.1016/j.imlet.2014.09.009 . The duplicate article has therefore been withdrawn.

PD-1-induced T cell exhaustion is controlled by a Drp1-dependent mechanism

2020

AbstractPD-1 signalling downregulates the T cell response, promoting an exhausted state in tumor-infiltrating T cells, through mostly unveiled molecular mechanisms. Drp1-dependent mitochondrial fission plays a crucial role to sustain T cell motility, proliferation, survival and glycolytic engagement and, interestingly, such processes are exactly those inhibited by PD-1 in tumor-infiltrating T cells. Here we show that the signature of PD-1pos CD8+ T cells infiltrating MC38-derived murine tumor mass is having downregulated Drp1 activity and more fused mitochondria, compared to PD-1neg counterparts. Also, PD-1pos lymphocytic elements infiltrating human colon cancer rarely express active Drp1. …

Grand Challenge in Viral Disease Investigation: An Endless Endeavor

2021

Food-mediated modulation of immunity in a phytophagous insect: An effect of nutrition rather than parasitic contamination.

2015

7 pages; International audience; Inherent to the cost of immunity, the immune system itself can exhibit tradeoffs between its arms. Phytophagous insects face a wide range of microbial and eukaryotic parasites, each activating different immune pathways that could compromise the activity of the others. Feeding larvae are primarily exposed to microbes, which growth is controlled by antibiotic secondary metabolites produced by the host plant. The resulting variation in abundance of microbes on plants is expected to differentially stimulate the insect antimicrobial immune defenses. Under the above tradeoff hypothesis, stimulation of the insect antimicrobial defenses is expected to compromise imm…