Search results for " IMMUNITY"
showing 10 items of 618 documents
Exploring a regulatory role for mast cells: 'MCregs'?
2010
Regulatory cells can mould the fate of the immune response by direct suppression of specific subsets of effector cells, or by redirecting effectors against invading pathogens and infected or neoplastic cells. These functions have been classically, although not exclusively, ascribed to different subsets of T cells. Recently, mast cells have been shown to regulate physiological and pathological immune responses, and thus to act at the interface between innate and adaptive immunity assuming different functions and behaviors at discrete stages of the immune response. Here, we focus on these poorly defined, and sometimes apparently conflicting, functions of mast cells.
Invertebrate Models in Innate Immunity and Tissue Remodeling Research
2022
The aim of this Special Issue is to highlight the close functional and highly conserved link between innate immunity, homeostasis maintenance, inflammation, tissue remodeling and regeneration [...]
The Role of Immunosenescence in Cerebral Small Vessel Disease: A Review.
2022
Cerebral small vessel disease (CSVD) is one of the most important causes of vascular dementia. Immunosenescence and inflammatory response, with the involvement of the cerebrovascular system, constitute the basis of this disease. Immunosenescence identifies a condition of deterioration of the immune organs and consequent dysregulation of the immune response caused by cellular senescence, which exposes older adults to a greater vulnerability. A low-grade chronic inflammation status also accompanies it without overt infections, an “inflammaging” condition. The correlation between immunosenescence and inflammaging is fundamental in understanding the pathogenesis of age-related CSVD (ArCSVD). Th…
Inflammation and Inflammatory Cell Recruitment in Acute Cerebrovascular Diseases
2015
Inflammation seems to play a major role in the pathogenesis of ischemic stroke as well as in other forms of brain damage. Ischemic brain injury induces a strong inflammatory response that begins in the microcirculation and involves several cell types and molecules, leading to neuronal death. The immune system is actively involved in the pathogenesis of acute brain damage through a set of events that include leukocyte and monocyte infiltration into the brain, activation of resident cells, including microglia, astrocytes and endothelial cells, and the elevated production of several inflammatory molecules, such as cytokines, that together play a complex role in the pathophysiology of ischemic …
Cell immunity in Coronary Artery Disease (CAD)
2015
Numerous researches have detected immune cellular elements in coronary lesions of atherosclerotic origin in human and animal models, and these cells are suspected of contributing to plaque instability. Patients affected by acute coronary syndrome present high levels of pro-inflammatory molecules, as shown in numerous studies. This finding implies similarity between CAD and well-known immune-mediated inflammatory diseases. Due to incongruent findings, this “infection hypothesis” cannot be rejected, thus further research is needed to better understand the relationship between pathogen-induced chronic inflammatory response, with its pathogenic mechanisms, and the atherosclerotic process. Sever…
Network of Cells and Mediators of Innate and Adaptive Cutaneous Immunity
2017
The skin is a major surface organ that translates external signals from the environment into local and systemic immune responses. As such, it is also strongly involved in fighting against cutaneous pathogens transmitted by arthropod vectors to the host. By harboring various skin-resident as well as highly motile immune cells and unique molecules, the skin orchestrates resulting immune responses against pathogens. Only an understanding of the complexity of skin immunity will lead to a better assessment of vector-induced alterations of resulting antipathogen immunity.
Microgravity-induced alterations in signal transduction in cells of the immune system
2010
Since decades it is known that the activity of cells of the immune system is severely dysregulated in microgravity, however, the underlying molecular aspects have not been elucidated yet. The identification of gravity-sensitive molecular mechanisms in cells of the immune system is an important and indispensable prerequisite for the development of counteractive measures to prevent or treat disturbed immune cell function of astronauts during long-term space missions. Moreover, their sensitivity to altered gravity renders immune cells an ideal model system to understand if and how gravity on Earth is required for normal mammalian cell function and signal transduction. We investigated the effec…
Physico-chimie des lipopolysaccharides et réponse inflammatoire : rôle des lipoprotéines
2014
LPS is a potent bacterial pro-inflammatory agent, consisting of hydrophilic, polysaccharide part and of a lipid A which is considered like active moiety. Nevertheless, the O chain of LPS influences their aggregation in aqueous media. Therefore, our goal has been to determine the role of O chain on the LPS biological and physiopathological effects. Our work was organized according to three main axes, and led to the following findings :- development of a new LPS assay by LC-MS/MS. The combination of this new technique with LAL test allowed us to calculate an inactivation ratio which reflects the ability of host organism to inactivate LPS, especially through their transfer to HDL by PLTP. The …
Localization of antimicrobial peptides in the tunic of Ciona intestinalis (Ascidiacea, Tunicata) and their involvement in local inflammatory-like rea…
2011
AbstractTunicates comprising a wide variety of different species synthesize antimicrobial peptides as important effector molecules of the innate immune system. Recently, two putative gene families coding for antimicrobial peptides were identified in the expressed sequence tag database of the tunicate Ciona intestinalis. Two synthetic peptides representing the cationic core region of one member of each of the families displayed potent antibacterial and antifungal activities. Moreover, the natural peptides were demonstrated to be synthesized and stored in distinct hemocyte types. Here, we investigated the presence of these natural peptides, namely Ci-MAM-A and Ci-PAP-A, in the tunic of C. int…
Immune mediators of sea-cucumber Holothuria tubulosa (Echinodermata) as source of novel antimicrobial and anti-staphylococcal biofilm agents
2013
The present study aims to investigate coelomocytes, immune mediators cells in the echinoderm Holothuria tubulosa, as an unusual source of antimicrobial and antibiofilm agents. The activity of the 5kDa peptide fraction of the cytosol from H. tubulosa coelomocytes (5-HCC) was tested against a reference group of Gram-negative and Gram-positive human pathogens. Minimal inhibitory concentrations (MICs) ranging from 125 to 500 mg/ml were determined against tested strains. The observed biological activity of 5-HCC could be due to two novel peptides, identified by capillary RP-HPLC/nESI-MS/MS, which present the common chemical-physical characteristics of antimicrobial peptides. Such peptides were c…