42 research outputs found
Intestinal Macrophages and DCs Close the Gap on Tolerance
CD103+ dendritic cells (DCs) must acquire soluble food antigens from the gut lumen to induce oral tolerance. In this issue of Immunity, Mazzini et al. (2014), report that CX3CR1+ macrophages capture such antigen and transfer it to the DCs by a route involving gap junctions
Regulatory T cells inhibit stable contacts between CD4+ T cells and dendritic cells in vivo
Regulatory T (T reg) cells exert powerful down-modulatory effects on immune responses, but it is not known how they act in vivo. Using intravital two-photon laser scanning microscopy we determined that, in the absence of T reg cells, the locomotion of autoantigen-specific T cells inside lymph nodes is decreased, and the contacts between T cells and antigen-loaded dendritic cells (DCs) are of longer duration. Thus, T reg cells can exert an early effect on immune responses by attenuating the establishment of stable contacts during priming of naive T cells by DCs
Моделирование струйного размыва донных отложений в нефтяных резервуарах
Объект исследования: электромеханическое устройство для размыва донных отложений в резервуарах вертикальных стальных. Предмет исследования – размыв донных отложений в резервуарах хранения нефти. Цель работы – Анализ существующих методов борьбы с донными отложениями. Моделирование гидродинамических процессов размыва донных отложений в резервуарах вертикальных стальных.Object of research: an electromechanical device for washing bottom sediments in vertical steel tanks. The subject of research is the erosion of bottom sediments in oil storage tanks. Purpose of the work - Analysis of existing methods for dealing with bottom sediments. Simulation of hydrodynamic processes of erosion of bottom sediments in vertical steel tanks
DC mobilization from the skin requires docking to immobilized CCL21 on lymphatic endothelium and intralymphatic crawling
Dermal DC mobilization requires docking to CCL21 on lymphatic endotheliu
Why Do We Feel Sick When Infected--Can Altruism Play a Role?
When we contract an infection, we typically feel sick and behave accordingly. Symptoms of sickness behavior (SB) include anorexia, hypersomnia, depression, and reduced social interactions. SB affects species spanning from arthropods to vertebrates, is triggered nonspecifically by viruses, bacteria, and parasites, and is orchestrated by a complex network of cytokines and neuroendocrine pathways; clearly, it has been naturally selected. Nonetheless, SB seems evolutionarily costly: it promotes starvation and predation and reduces reproductive opportunities. How could SB persist? Former explanations focused on individual fitness, invoking improved resistance to pathogens. Could prevention of disease transmission, propagating in populations through kin selection, also contribute to SB
Information regarding inflammation is communicated to the brain through parallel neural and circulatory routes [4,5].
<p>Leukocytes, such as dendritic cells (DCs) and macrophages, sense microbes through pathogen-recognition receptors such as toll-like receptors (TLRs) and NOD-like receptors (NLRs) and then release inflammatory cytokines such as interleukin–1 beta (IL–1β), IL–6, and tumor necrosis factor alpha (TNF-α). In the neural route, cytokines trigger activity in vagal afferents that innervate nuclei in the brain stem such at the nucleus of the solitary tract (NTS). These in turn relay the signal to various nuclei in the hypothalamus, thalamus, and amygdala [<a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1002276#pbio.1002276.ref004" target="_blank">4</a>]. In the circulatory route, microbial ligands and cytokines travel through the blood to reach the meninges, choroid plexus, and circumventricular organs (pink) where they can enter the brain. More recent data indicate that such ligands can also activate the epithelium in areas with an intact blood–brain barrier, causing it to synthetize various prostaglandins and release them into nuclei involved in specific behaviors [<a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1002276#pbio.1002276.ref006" target="_blank">6</a>].</p
The costs of SB to direct fitness.
<p>Behavioral (pink) and physiological (green) symptoms of SB can, either directly or indirectly, lead to maladaptive consequences (orange) that reduce individual fitness.</p
The benefits of SB to indirect fitness.
<p>Symptoms of SB (pink) can suppress (red connectors) or promote (green arrows) several mediating behaviors (yellow), consequently reducing pathogen transmission through several routes (blue).</p