scholarly journals Stress Granules in the Post-transcriptional Regulation of Immune Cells

Author(s):  
Nicolas Curdy ◽  
Olivia Lanvin ◽  
Sarah Cadot ◽  
Camille Laurent ◽  
Jean-Jacques Fournié ◽  
...  

Immune cell activation triggers transcriptional and translational programs eliciting cellular processes, such as differentiation or proliferation, essential for an efficient immune response. These dynamic processes require an intricate orchestration of regulatory mechanisms to control the precise spatiotemporal expression of proteins. Post-transcriptional regulation ensures the control of messenger RNA metabolism and appropriate translation. Among these post-transcriptional regulatory mechanisms, stress granules participate in the control of protein synthesis. Stress granules are ribonucleoprotein complexes that form upon stress, typically under control of the integrated stress response. Such structures assemble upon stimulation of immune cells where they control selective translational programs ensuring the establishment of accurate effector functions. In this review, we summarize the current knowledge about post-transcriptional regulation in immune cells and highlight the role of stress sensors and stress granules in such regulation.

2021 ◽  
Vol 14 ◽  
Author(s):  
Elise Liu ◽  
Léa Karpf ◽  
Delphine Bohl

Inflammation is a shared hallmark between amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). For long, studies were conducted on tissues of post-mortem patients and neuroinflammation was thought to be only bystander result of the disease with the immune system reacting to dying neurons. In the last two decades, thanks to improving technologies, the identification of causal genes and the development of new tools and models, the involvement of inflammation has emerged as a potential driver of the diseases and evolved as a new area of intense research. In this review, we present the current knowledge about neuroinflammation in ALS, ALS-FTD, and FTD patients and animal models and we discuss reasons of failures linked to therapeutic trials with immunomodulator drugs. Then we present the induced pluripotent stem cell (iPSC) technology and its interest as a new tool to have a better immunopathological comprehension of both diseases in a human context. The iPSC technology giving the unique opportunity to study cells across differentiation and maturation times, brings the hope to shed light on the different mechanisms linking neurodegeneration and activation of the immune system. Protocols available to differentiate iPSC into different immune cell types are presented. Finally, we discuss the interest in studying monocultures of iPS-derived immune cells, co-cultures with neurons and 3D cultures with different cell types, as more integrated cellular approaches. The hope is that the future work with human iPS-derived cells helps not only to identify disease-specific defects in the different cell types but also to decipher the synergistic effects between neurons and immune cells. These new cellular tools could help to find new therapeutic approaches for all patients with ALS, ALS-FTD, and FTD.


Author(s):  
Xiang Yu ◽  
Bishwas Sharma ◽  
Brian D Gregory

Abstract Ribonucleotides within the various RNA molecules in eukaryotes are marked with more than 160 distinct covalent chemical modifications. These modifications include those that occur internally in messenger RNA (mRNA) molecules such as N6-methyladenosine (m6A) and 5-methylcytosine (m5C), as well as those that occur at the ends of the modified RNAs like the non-canonical 5′ end nicotinamide adenine dinucleotide (NAD+) cap modification of specific mRNAs. Recent findings have revealed that covalent RNA modifications can impact the secondary structure, translatability, functionality, stability and degradation of the RNA molecules in which they are included. Many of these covalent RNA additions have also been found to be dynamically added and removed through writer and eraser complexes, respectively, providing a new layer of epitranscriptome-mediated post-transcriptional regulation that regulates RNA quality and quantity in eukaryotic transcriptomes. Thus, it is not surprising that the regulation of RNA fate mediated by these epitranscriptomic marks has been demonstrated to have widespread effects on plant development and the responses of these organisms to abiotic and biotic stresses. In this review, we highlight recent progress focused on the study of the dynamic nature of these epitranscriptome marks and their roles in post-transcriptional regulation during plant development and response to environmental cues, with an emphasis on the mRNA modifications of non-canonical 5′ end NAD+ capping, m6A and several other internal RNA modifications.


2017 ◽  
Vol 313 (2) ◽  
pp. L406-L415 ◽  
Author(s):  
Gene T. Yocum ◽  
Damian L. Turner ◽  
Jennifer Danielsson ◽  
Matthew B. Barajas ◽  
Yi Zhang ◽  
...  

Emerging evidence indicates that hypnotic anesthetics affect immune function. Many anesthetics potentiate γ-aminobutyric acid A receptor (GABAAR) activation, and these receptors are expressed on multiple subtypes of immune cells, providing a potential mechanistic link. Like immune cells, airway smooth muscle (ASM) cells also express GABAARs, particularly isoforms containing α4-subunits, and activation of these receptors leads to ASM relaxation. We sought to determine if GABAAR signaling modulates the ASM contractile and inflammatory phenotype of a murine allergic asthma model utilizing GABAAR α4-subunit global knockout (KO; Gabra40/0) mice. Wild-type (WT) and Gabra4 KO mice were sensitized with house dust mite (HDM) antigen or exposed to PBS intranasally 5 days/wk for 3 wk. Ex vivo tracheal rings from HDM-sensitized WT and Gabra4 KO mice exhibited similar magnitudes of acetylcholine-induced contractile force and isoproterenol-induced relaxation ( P = not significant; n = 4). In contrast, in vivo airway resistance (flexiVent) was significantly increased in Gabra4 KO mice ( P < 0.05, n = 8). Moreover, the Gabra4 KO mice demonstrated increased eosinophilic lung infiltration ( P < 0.05; n = 4) and increased markers of lung T-cell activation/memory (CD62L low, CD44 high; P < 0.01, n = 4). In vitro, Gabra4 KO CD4+ cells produced increased cytokines and exhibited increased proliferation after stimulation of the T-cell receptor as compared with WT CD4+ cells. These data suggest that the GABAAR α4-subunit plays a role in immune cell function during allergic lung sensitization. Thus GABAAR α4-subunit-specific agonists have the therapeutic potential to treat asthma via two mechanisms: direct ASM relaxation and inhibition of airway inflammation.


1996 ◽  
Vol 10 (4) ◽  
pp. 243-248 ◽  
Author(s):  
Mary H Perdue

Many studies have provided evidence that the immune system is a key regulatory system of intestinal function. The interaction of immune cells with the gut epithelium plays an important role in host defence, acting to eliminate pathogens, antigens and other noxious material from the lumen of the gastrointestinal tract. During inflammatory conditions of the gut, the mucosa becomes packed with immune cells in close proximity to the enterocytes. Mediators released from these cells have profound effects on epithelial functions. The two main functions of the intestinal epithelium are to transport nutrients, ions and water, and to act as a barrier to prevent unimpeded uptake of antigenic material and microbes from the lumen. Both these functions are altered by immune reactions in response to various stimuli. Topics discussed include mast cells and epithelial function; mast cell-nerve interaction; mast cell activation; neutrophils, eosinophils and macrophages; T cells; and prostaglandins and immune cell activation.


1994 ◽  
Vol 267 (2) ◽  
pp. G151-G165 ◽  
Author(s):  
M. H. Perdue ◽  
D. M. McKay

Over the past ten years, it has become evident that intestinal epithelial functions such as ion secretion are a host defense response to the presence of antigens, microbes, and other noxious substances in the gut lumen. Such responses are mediated by the activation of immune cells in the mucosa causing release of chemical mediators that act directly or indirectly on the epithelium. Frequently, immune cell products stimulate enteric nerves resulting in amplification. Thus immune cells and nerves form interactive units that can recognize various stimuli both specifically and nonspecifically and initiate mechanisms to eliminate offending material. Here, we review the current state of knowledge regarding immune regulation of epithelial physiology with particular emphasis on the ability of immune cells and their products (biogenic amines, cytokines, arachidonic acid metabolites, oxidants) to alter electrolyte transport. The mast cell will be highlighted in this scheme as this cell has been, and continues to be, the focus of extensive research efforts. However, recently it has become apparent that cells such as lymphocytes, macrophages, and polymorphonuclear leukocytes also play important roles in immunophysiology. The effect of immune cell activation on epithelial functions other than transport, such as permeability, proliferation, and antigen presentation, will be described where appropriate. Finally, we will present evidence that the enterocyte can express an "activated" phenotype and thus participate directly in mucosal immune responses.


2021 ◽  
Author(s):  
Fabio Nicolini ◽  
Massimiliano Mazza

The interplay between the immune system and the pleural mesothelium is crucial both for the development of malignant pleural mesothelioma (MPM) and for the response of MPM patients to therapy. MPM is heavily infiltrated by several immune cell types which affect the progression of the disease. The presence of organized tertiary lymphoid structures (TLSs) witness the attempt to fight the disease in situ by adaptive immunity which is often suppressed by tumor expressed factors. In rare patients physiological, pharmacological or vaccine-induced immune response is efficient, rendering their plasma a valuable resource of anti-tumor immune cells and molecules. Of particular interest are human antibodies targeting antigens at the tumor cell surface. Here we review current knowledge regarding MPM immune infiltration, MPM immunotherapy and the harnessing of this response to identify novel biologics as biomarkers and therapeutics through innovative screening strategies.


2021 ◽  
Author(s):  
Anna Cinkajzlová ◽  
Milos Mraz ◽  
Martin Haluzik

Immune cells are an inseparable component of adipose tissue intimately involved in most of its functions. Physiologically, they regulate adipose tissue homeostasis, while in case of adipose tissue stress immune cells are able to change their phenotype, enhance their count and subsequently contribute to the development and maintenance of local adipose tissue inflammation. Immune cells are an important source of inflammatory cytokines and other pro-inflammatory products that further influence not only surrounding tissues, but via systemic circulation also the whole organism being thus one of the main factors responsible for the transition from simple obesity to associated metabolic and cardiovascular complications. The purpose of this review is to summarize current knowledge on different adipose tissue immune cell subsets and their role in the development of obesity, type 2 diabetes mellitus and cardiovascular diseases.


Cancers ◽  
2021 ◽  
Vol 13 (17) ◽  
pp. 4364
Author(s):  
Joost B. Koedijk ◽  
Inge van der Werf ◽  
Friso G. Calkoen ◽  
Stefan Nierkens ◽  
Gertjan J. L. Kaspers ◽  
...  

Immunotherapeutic agents may be an attractive option to further improve outcomes and to reduce treatment-related toxicity for pediatric AML. While improvements in outcome have been observed with immunotherapy in many cancer types, immunotherapy development and implementation into patient care for both adult and pediatric AML has been hampered by an incomplete understanding of the bone marrow environment and a paucity of tumor-specific antigens. Since only a minority of patients respond in most immunotherapy trials across different cancer types, it will be crucial to understand which children with AML are likely to respond to or may benefit from immunotherapies. Immune cell profiling efforts hold promise to answer this question, as illustrated by the development of predictive scores in solid cancers. Such information on the number and phenotype of immune cells during current treatment regimens will be pivotal to generate hypotheses on how and when to intervene with immunotherapy in pediatric AML. In this review, we discuss the current understanding of the number and phenotype of immune cells in the bone marrow in pediatric AML, ongoing immunotherapy trials and how comprehensive immune profiling efforts may pave the way for successful clinical trials (and, ultimately, implementation into patient care).


Catalysts ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 81 ◽  
Author(s):  
Angelo Spinello ◽  
Ida Ritacco ◽  
Alessandra Magistrato

Cytochromes P450 (CYP450s) promote the biosynthesis of steroid hormones with major impact on the onset of diseases such as breast and prostate cancers. By merging distinct functions into the same catalytic scaffold, steroidogenic CYP450s enhance complex chemical transformations with extreme efficiency and selectivity. Mammalian CYP450s and their redox partners are membrane-anchored proteins, dynamically associating to form functional machineries. Mounting evidence signifies that environmental factors are strictly intertwined with CYP450s catalysis. Atomic-level simulations have the potential to provide insights into the catalytic mechanism of steroidogenic CYP450s and on its regulation by environmental factors, furnishing information often inaccessible to experimental means. In this review, after an introduction of computational methods commonly employed to tackle these systems, we report the current knowledge on three steroidogenic CYP450s—CYP11A1, CYP17A1, and CYP19A1—endowed with multiple catalytic functions and critically involved in cancer onset. In particular, besides discussing their catalytic mechanisms, we highlight how the membrane environment contributes to (i) regulate ligand channeling through these enzymes, (ii) modulate their interactions with specific protein partners, (iii) mediate post-transcriptional regulation induced by phosphorylation. The results presented set the basis for developing novel therapeutic strategies aimed at fighting diseases originating from steroid metabolism dysfunction.


2021 ◽  
Vol 41 (1) ◽  
Author(s):  
Inga Wessels ◽  
Henrike Josephine Fischer ◽  
Lothar Rink

Evidence for the importance of zinc for all immune cells and for mounting an efficient and balanced immune response to various environmental stressors has been accumulating in recent years. This article describes the role of zinc in fundamental biological processes and summarizes our current knowledge of zinc's effect on hematopoiesis, including differentiation into immune cell subtypes. In addition, the important role of zinc during activation and function of immune cells is detailed and associated with the specific immune responses to bacteria, parasites, and viruses. The association of zinc with autoimmune reactions and cancers as diseases with increased or decreased immune responses is also discussed. This article provides a broad overview of the manifold roles that zinc, or its deficiency, plays in physiology and during various diseases. Consequently, we discuss why zinc supplementation should be considered, especially for people at risk of deficiency. Expected final online publication date for the Annual Review of Nutrition, Volume 41 is September 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.


Sign in / Sign up

Export Citation Format

Share Document