Клеточное старение: механизмы и клиническое значение1 Федеральное государственное бюджетное учреждение «Государственный научный центр «Институт иммунологии» Федерального медико-биологического агентства, 115522, г

Background. Chronic sinusitis occurs in the Russian Federation in 16.4±10.89% of the population and has a great impact on the quality of life of patients. The inflammatory process underlying this pathology is often resistant to conservative treatment and causes surgical intervention. The study of the role of neutrophil extracellular traps as an important part of the immune response, as well as the capabilities of drugs capable of influencing the processes of netosis, is an important and relevant area of modern research. Aim. Studying the role of NETs in the pathogenesis of CRS without polyps, assessing the effect of azoximer bromide on the metabolism of NETs in patients with CRS. Materials and methods. The study included 82 patients diagnosed with chronic rhinosinusitis (average age 37±12 years), and 40 healthy volunteers (average age 34±10 years). Patients with CRS were treated with surgery and a course of azoximer bromide, the severity of the disease did not differ in patients. Nasal secretions and venous blood were analyzed in all study participants with the determination of surrogate markers of neutrophil extracellular traps – myeloperoxidase complexes with DNA and the detection of double-stranded DNA (Quant Pico Green dsDNA kit). In patients who received azoximer bromide, the material was taken twice – before the start of treatment and 10 days after the course of treatment. Results. In patients with CRS, the amount of NETs in nasal secretions and venous blood is higher compared to the control group (p0.05). The use of azoximer bromide in CRS outside of exacerbation reduces the activity of NETosis processes with intranasal use of the drug not only in the area of inflammation (reduction of NET in nasal secretions); p0.05, but also at the general level (decrease NETs in venous blood); p0.05. Conclusion. An increase in the amount of NETs in nasal flushes and venous blood in patients with CRS without exacerbation compared with the control group may indicate a likely pathological role of NETosis processes, and an increase in the amount of NETs in the blood of patients with CRS without exacerbation compared with the control group indicates the systemic effect of a local inflammatory process in the mucous membrane of the nasal cavity and paranasal sinuses.

We performed a simultaneous analysis of cytokine expression and metabolic reprogramming of macrophages upon combined stimulation of NOD1 and TLR4 receptors of innate immunity. NOD1 and TLR4 agonists boosted main parameters of glycolysis (extracellular acidification rate, glucose consumption, lactate release). However, changes of these parameters upon combined stimulation were not greater than those induced by stimulation of each individual receptor. At the same time, combined stimulation synergistically induced pro-inflammatory cytokine production and mRNA expression at relatively late time points (4–9 hours) after addition of agonists. In all, metabolic reprogramming may support synergistic induction of cytokines upon combined NOD1 and TLR4 stimulation; however, the origin of this synergy is in the synergistic induction of cytokine gene expression.

Аэробный гликолиз не играет незаменимой роли в продукции провоспалительных цитокинов дендритными клетками 1 Федеральное государственное бюджетное учреждение «Государственный научный центр «Институт иммунологии» Федерального медико-биологического агентства, 115522, г.Москва, Российская Федерация 2 Федеральное государственное бюджетное образовательное учреждение высшего образования «Московский государственный университет имени М.В.Ломоносова», 119991, г.Москва, Российская Федерация 3 Федеральное государственное автономное образовательное учреждение высшего образования Российский научный исследовательский медицинский университет им.Н.И.Пирогова Министерства здравоохранения Российской Федерации, 119997, г.Москва, Российская Федерация 4 Федеральное государственное бюджетное учреждение «Национальный медицинский исследовательский центр онкологии им

Innate immune defense mechanisms activated by pathogen recognition can be roughly divided into two categories: 1) those aimed at direct killing of the pathogen (microbicidal);2) those aimed at the development of inflammation (pro-inflammatory) The final goal of both types of mechanisms is elimination of the pathogen and restoration of homeostasis However, inflammation is accompanied by damage of self tissues, which often has a negative impact on the outcome of infection Therefore, there is a need in such approaches to immunoprophylaxy and immunotherapy of infections that would enhance antimicrobial defense while minimizing inflammation A key approach is elevation of epithelial barrier resistance The proposed concept of immunostimulation is exemplified using COVID-19 infection Защитные механизмы врожденной иммунной системы, активируемые в ответ на распознавание патогена, можно условно разделить на две категории: 1) направленные на непосредственное уничтожение патогена (микробицидные);2) направленные на развитие воспаления (провоспалительные) И те, и другие имеют целью элиминацию возбудителя и восстановление постоянства внутренней среды организма Однако воспаление сопровождается повреждением собственных тканей, что во многих случаях негативно сказывается на исходе инфекционного процесса Поэтому необходимы такие подходы к иммунопрофилактике и иммунотерапии инфекций, которые обеспечивали бы усиление антимикробной защиты при минимизации воспаления Одним из основных способов решения этой задачи является повышение резистентности эпителиальных барьеров Предлагаемая концепция иммуностимуляции рассматривается на примере инфекции COVID-19

We provide the fi rst characterization of glucose and energy metabolism rearrangements in human macrophages upon their activation with a NOD1 receptor agonist (N-acetyl-D-muramyl-L-alanylD-isoglutamyl-meso-diaminopimelic acid, or M-triDAP) in comparison with the eff ects of a TLR4 agonist, lipopolysaccharide (LPS). We demonstrate possibilities of modulation of cytokine production by macrophages using glycolysis inhibitors.

Nucleotide-binding oligomerization domain (NOD) 1 and NOD2 are pattern-recognition receptors responsible for sensing fragments of bacterial peptidoglycan known as muropeptides. Stimulation of innate immunity by systemic or local administration of NOD1 and NOD2 agonists is an attractive means to prevent and treat infectious diseases. In this review, we discuss novel data concerning structural features of selective and non-selective (dual) NOD1 and NOD2 agonists, main signaling pathways and biological effects induced by NOD1 and NOD2 stimulation, including induction of pro-inflammatory cytokines, type I interferons and antimicrobial peptides, induction of autophagy, alterations of metabolism. We also discuss interactions between NOD1/NOD2 and Toll-like receptor agonists in terms of synergy and cross-tolerance. Finally, we review available animal data on the role of NOD1 and NOD2 in protection against infections, and discuss how these data could be applied in human infectious diseases.

Agonists of nucleotide oligomerization domain (NOD) 1 and NOD2 receptors represent a promising class of immunostimulants and immunological adjuvants. Here, we describe a cell-based test system to assess their pharmacokinetics. In this system, NOD1 and NOD2 agonist concentrations in sera are determined using a reporter cell line, 293Luc, which contains an NF-κB-inducible luciferase reporter construct and naturally expresses NOD1 and NOD2. The 293Luc cells dose-dependently respond to different NOD1 and NOD2 agonists in the nanomolar to low-micromolar concentration range. To verify that the NF-κB-inducing activity of serum samples is due to the administered agonist and not to secondarily induced endogenous molecules, a 293Luc-derived NOD1/NOD2 double-knockout clone is used. Within-run and between-run precisions of the system are <15% and <20%, respectively. Applicability of the novel assay is illustrated by studying pharmacokinetics of two specific NOD2 agonists (N‑acetyl‑d‑glucosaminyl‑N‑acetyl‑d‑muramyl‑l‑alanyl‑d‑isoglutamine and N‑glycolyl‑d‑muramyl‑l‑alanyl‑d‑isoglutamine) and a specific NOD1 agonist (N‑acetyl‑d‑glucosaminyl‑N‑acetyl‑d‑sorbitolamine‑d‑lactoyl‑l‑alanyl‑d‑isoglutamyl‑meso‑diaminopimelic acid). In summary, the test system described here can potentially be used to assess pharmacokinetics of NOD1 and NOD2 agonists in different animal species.

Interactions between pattern recognition receptors (PRRs) shape innate immune responses to particular classes of pathogens. Here, we review interactions between TLRs and nucleotide-binding oligomerization domain 1 and 2 (NOD1 and NOD2) receptors, two major groups of PRRs involved in innate recognition of bacteria. Most of experimental data both in vitro and in vivo suggest that NODs and TLRs synergize with each other at inducing the production of cytokines and antimicrobial peptides. Molecular mechanisms of this synergy remain poorly understood, although several scenarios can be proposed: (i) direct interactions of signaling pathways downstream of NODs and TLRs; (ii) mutual transcriptional regulation of unique components of NOD-dependent and TLR-dependent signaling pathways; and (iii) interactions at the post-transcriptional level. Potential practical implications of NOD-TLR synergy are dual. In sepsis, where synergistic effects probably contribute to excessive proinflammatory cytokine production, blockade of NOD1, and/or NOD2 in addition to TLR4 blockade may be required to achieve therapeutic benefit. On the other hand, synergistic combinations of relatively small doses of NOD and TLR agonists administered before infection could be used to boost innate resistance against bacterial pathogens.

Activation of nucleotide-binding oligomerization domain (NOD) 1 and NOD2 by muropeptides triggers a complex transcriptional program in innate immune cells. However, little is known about posttranscriptional regulation of NOD1- and NOD2-dependent responses. When stimulated with a prototypic NOD1 agonist, N-acetylglucosaminyl-N-acetylmuramyl-l-alanyl-d-isoglutamyl-meso-diaminopimelic acid (GM-triDAP), human monocyte-derived macrophages (MDM) produced an order of magnitude more TNF, IL-6, and pro-IL-1β than did monocyte-derived dendritic cells (MDDC), despite similar NOD1 expression, similar cytokine mRNA kinetics, and comparable responses to LPS. TNF production by GM-triDAP-activated MDM was independent of autocrine IL-1. However, GM-triDAP-activated MDM translated TNF mRNA more efficiently than did MDDC. As an underlying mechanism, NOD1 triggering in MDM caused a more potent and long-lasting activation of the signaling axis involving p38 MAPK, MAPK-interacting kinase (MNK), and eukaryotic translation initiation factor 4E, which is a critical regulator of translation. Furthermore, MNK controlled TNF mRNA abundance in MDDC and MDM upon NOD1 triggering. NOD1-dependent responses were more sensitive to MNK inhibition than were TLR4-dependent responses. These results demonstrate the importance of the p38-MNK-eukaryotic translation initiation factor 4E axis in TNF production downstream of NOD1.

Neutrophils can entrap and kill pathogens by releasing of neutrophil extracellular traps (NETs), in addition to their routine functions such as phagocytosis and degranulation. NETs consist of a DNA backbone supplemented by multiple bactericidal proteins from the nucleus, the cytoplasm and the granules. Neutrophils release NETs after their activation by a number of physiological and pharmacological stimuli. In addition to the antimicrobial function, NETs are involved in the pathogenesis of various autoimmune and inflammatory diseases. Since NET formation predominantly depends on the generation of reactive oxygen species (ROS), all substances that are capable of scavenging ROS or inhibiting the enzymes responsible for their synthesis should prevent ROS-associated NET release. The aim of this study was to test substances with an antioxidant activity, such as Trolox, Tiron, and Tempol, for their capacity to inhibit NET formation by primary human neutrophils in vitro. We revealed for the first time an inhibitory effect of Trolox on ROS-dependent NET release. We also established a suppressive effect of Tempol on NET formation that manifested itself in a wide range of concentrations. In this study, no inhibitory influence of Tiron on NET release was revealed. All tested substances exerted a significant dose-dependent antioxidative effect on ROS generation induced by phorbol 12-myristate 13-acetate (PMA). We suggest that the antioxidants Trolox and Tempol should be recommended for treating autoimmune and inflammatory diseases that implicate ROS-dependent NET release.

The cationic antimicrobial peptide, LL37, forms electrostatic complexes with DNA (LL37-DNA), which are potent activators of circulating plasmacytoid predendritic cells (ppDCs) and monocytes. However, the effects of LL37-DNA on other immune cell types, such as NK cells, are poorly characterized. In this study, we show that complexes of human genomic DNA (hgDNA) or synthetic double-stranded oligodeoxynucleotides with LL37 strongly enhance natural cytotoxicity of human peripheral blood mononuclear cells (PBMCs) upon an overnight culture, whereas hgDNA alone has no effect, and LL37 alone is moderately active. LL37-DNA complexes potentiate degranulation of, and interferon (IFN)-γ production by, NK cells upon subsequent encounter of K562 target cells. The complexes do not influence percentages of NK cells among PBMCs or the expression of cytotoxic proteins by NK cells. Using neutralizing anticytokine antibodies and immunomagnetic depletion of different subpopulations of PBMCs, we found that the effect of LL37-DNA on NK cells is indirect and mediated by type I IFNs produced by monocytes and, to a lesser extent, by ppDCs. We discuss possible roles of LL37-DNA complexes in the regulation of NK cell functions and in the treatment of cancer.

The goal of our research was comparative study of the most important parameters of subset cytoarchitectonics in the patients with the different courses of myocarditis and evaluation of their pathoge$ netic and clinical value in the practice of the physician. We have investigated 99 patients with myocarditis and 40 healthy donors. In patients with malignant course of

In present study, the following low-MW inhibitors were used to dissect mechanisms of action for two muramyl peptide components of Polymuramyl, an immunomodulatory drug: (1) N-acetyl-D-glucosaminyl-(β1→4)-N-acetyl-D-muramoyl-L-alanyl-D-isoglutaminyl-meso-diaminopimelic acid (GMtri); (2) a dimeric muramyl peptide (diGMtetra), wherein two monomers [N-acetyl-D-glucosaminyl-(β1→4)-N-acetyl-D-muramoyl-L-alanyl-D-isoglutaminyl-meso-diaminopimeloyl-D-alanin] are linked via an amide bond between the carboxyl group of terminal D-alanin at one monomer and the ω-amino group of meso-diaminopimelic acid at another monomer. In vitro production of tumor necrosis factor (TNF) by human macrophages stimulated with GMtri or diGMtetra was shown to be inhibited by SB203580 (a RIP2 kinase inhibitor), genistein (a protein tyrosine kinase inhibitor) and BAY 11-7082 (an IκB-kinase inhibitor). Moreover, response to diGMtetra was inhibited by dynasore (an inhibitor of clathrin-dependent endocytosis), as well as by a broad-range protease-inhibiting cocktail. Thus, activating effects upon macrophages induced by the Polymuramyl components is provided by, at least, three biological processes: (1) clathrin-dependent endocytosis; (2) peptidase-mediated processing of diGMtetra; 3) activation of a signal chain RIP2 – IκB-kinase – NF-κB transcription factor.