scholarly journals Molecular mechanisms of control of differentiation of regulatory t-lymphocytes by exogenous melatonin

2019 ◽  
Vol 484 (2) ◽  
pp. 224-227
Author(s):  
N. S. Glebezdina ◽  
A. A. Olina ◽  
I. V. Nekrasova ◽  
E. M. Kuklina

We investigated the role of epiphyseal hormone melatonin in the differentiation of naive CD4+T cells into regulatory T cells (Treg). The hormone at physiological and pharmacological concentrations inhibited Treg differentiation, decreasing both the proportion of CD4+FOXP3+ cells in the culture and the level of TGF‑β, the key cytokine for this T cell subpopulation. The inhibitory effect of exogenous melatonin was due to its interaction with the membrane receptors MT1 and MT2. At the same time, the signals realized through RORa — the nuclear receptor for melatonin — stimulated Treg formation; however, they were considerably weaker than the signals from the membrane receptors and were overlapped by the latter. Since the Treg subpopulation plays an important role in physiological and pathological processes in the body, the revealed effects of melatonin should be taken into account in its therapeutic use.

Author(s):  
Ya.O. Yemchenko ◽  
K.Ye. Ishcheikin ◽  
I.P. Kaidashev

Psoriasis is one of the most common chronic recurrent systemic autoimmune multifactorial diseases, affected the skin, joints, internal organs and systems of the body. Despite the significant prevalence of psoriasis and a large number of studies devoted this problem there is still no single view on the pathogenesis of this dermatosis. To clear up the pathogenesis of psoriasis, it seems to be reasonable to focus on the common comorbidities or multimorbidities, which may occur in the course of psoriasis, as this issue is still insufficiently studied. Recent reports have proven the evidences of indisputable link between psoriasis and obesity. The scientific literature extensively covers the issues of identical pathogenetic mechanisms of inflammatory processes in psoriasis and obesity. Given the current data on the role of systemic inflammation underlying the development of both psoriasis and obesity, the study of molecular mechanisms of its development and in particularly the role of proinflammatory nuclear transcription factors, thiazolidinediones have been found out as pathogenetically justified medicine of choice for the therapy of these diseases. In this study, we determined the effectiveness of using 30 mg of pioglitazone daily for 6 months in the course of treatment for patients with extensive psoriasis vulgaris of moderate severity, who were also diagnosed as having concomitant grade І-ІІ alimentary obesity that was supported by clinical and immunological findings evidenced of systemic inflammation. Analyzing the results obtained, we have found out the prolonged therapy with pioglitazone leads to a decrease in systemic inflammation and contributes to a milder recurrent course of psoriasis.


2021 ◽  
Vol 17 (13) ◽  
pp. 1683-1694
Author(s):  
Daniel J Craig ◽  
Nisha S Nanavaty ◽  
Monika Devanaboyina ◽  
Laura Stanbery ◽  
Danae Hamouda ◽  
...  

Radiation therapy (RT) in some cases results in a systemic anticancer response known as the abscopal effect. Multiple hypotheses support the role of immune activation initiated by RT-induced DNA damage. Optimal radiation dose is necessary to promote the cGAS-STING pathway in response to radiation and initiate an IFN-1 signaling cascade that promotes the maturation and migration of dendritic cells to facilitate antigen presentation and stimulation of cytotoxic T cells. T cells then exert a targeted response throughout the body at areas not subjected to RT. These effects are further augmented through the use of immunotherapeutic drugs resulting in increased T-cell activity. Tumor-infiltrating lymphocyte presence and TREX1, KPNA2 and p53 signal expression are being explored as prognostic biomarkers.


Rheumatology ◽  
2020 ◽  
Vol 60 (1) ◽  
pp. 420-429
Author(s):  
Takayuki Katsuyama ◽  
Hao Li ◽  
Suzanne M Krishfield ◽  
Vasileios C Kyttaris ◽  
Vaishali R Moulton

Abstract Objective CD4 T helper 1 (Th1) cells producing IFN-γ contribute to inflammatory responses in the pathogenesis of SLE and lupus nephritis. Moreover, elevated serum type II IFN levels precede the appearance of type I IFNs and autoantibodies in patient years before clinical diagnosis. However, the molecules and mechanisms that control this inflammatory response in SLE remain unclear. Serine/arginine-rich splicing factor 1 (SRSF1) is decreased in T cells from SLE patients, and restrains T cell hyperactivity and systemic autoimmunity. Our objective here was to evaluate the role of SRSF1 in IFN-γ production, Th1 differentiation and experimental nephritis. Methods T cell-conditional Srsf1-knockout mice were used to study nephrotoxic serum-induced nephritis and evaluate IFN-γ production and Th1 differentiation by flow cytometry. RNA sequencing was used to assess transcriptomics profiles. RhoH was silenced by siRNA transfections in human T cells by electroporation. RhoH and SRSF1 protein levels were assessed by immunoblots. Results Deletion of Srsf1 in T cells led to increased Th1 differentiation and exacerbated nephrotoxic serum nephritis. The expression levels of RhoH are decreased in Srsf1-deficient T cells, and silencing RhoH in human T cells leads to increased production of IFN-γ. Furthermore, RhoH expression was decreased and directly correlated with SRSF1 in T cells from SLE patients. Conclusion Our study uncovers a previously unrecognized role of SRSF1 in restraining IFN-γ production and Th1 differentiation through the control of RhoH. Reduced expression of SRSF1 may contribute to pathogenesis of autoimmune-related nephritis through these molecular mechanisms.


Antibodies ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 44
Author(s):  
Lamin B. Cham ◽  
Tom Adomati ◽  
Fanghui Li ◽  
Murtaza Ali ◽  
Karl S. Lang

The integrin associated protein (CD47) is a widely and moderately expressed glycoprotein in all healthy cells. Cancer cells are known to induce increased CD47 expression. Similar to cancer cells, all immune cells can upregulate their CD47 surface expression during infection. The CD47-SIRPa interaction induces an inhibitory effect on macrophages and dendritic cells (dendritic cells) while CD47-thrombospondin-signaling inhibits T cells. Therefore, the disruption of the CD47 interaction can mediate several biologic functions. Upon the blockade and knockout of CD47 reveals an immunosuppressive effect of CD47 during LCMV, influenza virus, HIV-1, mycobacterium tuberculosis, plasmodium and other bacterial pneumonia infections. In our recent study we shows that the blockade of CD47 using the anti-CD47 antibody increases the activation and effector function of macrophages, dendritic cells and T cells during viral infection. By enhancing both innate and adaptive immunity, CD47 blocking antibody promotes antiviral effect. Due to its broad mode of action, the immune-stimulatory effect derived from this antibody could be applicable in nonresolving and (re)emerging infections. The anti-CD47 antibody is currently under clinical trial for the treatment of cancer and could also have amenable therapeutic potential against infectious diseases. This review highlights the immunotherapeutic targeted role of CD47 in the infectious disease realm.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 2187-2187
Author(s):  
Hong Liu ◽  
Fan Dong

Abstract Granulocyte colony-stimulating factor (G-CSF) supports the proliferation, differentiation and survival of myeloid cells by stimulating the activation of several signaling cascades including the serine/threonine kinase Akt pathway. Akt activation has been shown to be important for G-CSF-induced survival and granulocytic differentiation. Although significant progresses have been made in our understanding of the molecular mechanisms by which Akt is activated, much less is known about the signaling events that negatively regulate Akt activation. Interestingly, G-CSF-induced activation of Akt was completely inhibited when myeloid 32D cells transfected with the wild type G-CSF receptor were incubated with phorbol-12-myristate 13-acetate (PMA), a PKC activator. PMA-mediated inhibition of Akt activation occurred with 5 min and lasted at least 1 hour. Previously, it has been shown that a carboxyl terminally truncated G-CSF receptor (D715), whose expression is associated with the development of acute myeloid leukemia in patients with severe congenital neutropenia (SCN), mediates significantly prolonged Akt activation. Notably, Akt activation by G-CSF in 32D cells expressing the D715 receptor mutant was rapidly downregulated by PMA treatment. The inhibitory effect of PMA on Akt activation was abolished by pretreatment of cells with the specific PKC inhibitor GF109203X, suggesting that PKC-dependent pathway negatively regulates Akt activation. Ro-31-7549, a specific inhibitor of PKCe, also abrogated PMA-mediated inhibition of Akt activation whereas rottlerin and Go6976, inhibitors of PKCd and PKC a/bI,, respectively, displayed no effect. Together, these results identified PKCe as being critically involved in PMA-mediated inhibition of Akt activation. Experiments are currently under way to determine the mechanism by which PKCe downregulates Akt activation and the role of PKCe in the regulation of cell proliferation, differentiation and survival in response to G-CSF.


2021 ◽  
Author(s):  
Alvaro Baeza Garcia ◽  
Edwin Siu ◽  
Xin Du ◽  
Lin Leng ◽  
Blandine Franke-Fayard ◽  
...  

AbstractMalaria begins when mosquito-borne Plasmodium sporozoites invade hepatocytes and usurp host pathways to support the differentiation and multiplication of erythrocyte-infective merozoite progeny. The deadliest complication of infection, cerebral malaria, accounts for the majority of malarial fatalities. Although our understanding of the cellular and molecular mechanisms underlying the pathology remains incomplete, recent studies support the contribution of systemic and neuroinflammation as the cause of cerebral edema and blood-brain barrier (BBB) dysfunction. All Plasmodium species encode an orthologue of the innate cytokine, Macrophage Migration Inhibitory Factor (MIF), which functions in mammalian biology to regulate innate responses. Plasmodium MIF (PMIF) similarly signals through the host MIF receptor CD74, leading to an enhanced inflammatory response. We investigated the PMIF-CD74 interaction in the onset of experimental cerebral malaria (ECM) using CD74 deficient (Cd74−/−) mice, which were found to be protected from ECM. The protection was associated with the inability of brain microvessels from Cd74−/− hosts to present parasite antigen to sequestered Plasmodium-specific CD8+ T cells. Infection of mice with PMIF-deficient sporozoites (PbAmif-) also protected mice from ECM, highlighting the pivotal role of PMIF in the pre-erythrocytic stage of the infection. A novel pharmacologic PMIF-selective antagonist reduced PMIF/CD74 signaling and fully protected mice from ECM. These findings reveal a conserved mechanism for Plasmodium usurpation of host CD74 signaling and suggest a tractable approach for new pharmacologic intervention.


2021 ◽  
Vol 12 ◽  
Author(s):  
Ana Valle-Noguera ◽  
Anne Ochoa-Ramos ◽  
Maria José Gomez-Sánchez ◽  
Aranzazu Cruz-Adalia

Type 3 Innate lymphoid cells (ILC3s) have been described as tissue-resident cells and characterized throughout the body, especially in mucosal sites and classical first barrier organs such as skin, gut and lungs, among others. A significant part of the research has focused on their role in combating pathogens, mainly extracellular pathogens, with the gut as the principal organ. However, some recent discoveries in the field have unveiled their activity in other organs, combating intracellular pathogens and as part of the response to viruses. In this review we have compiled the latest studies on the role of ILC3s and the molecular mechanisms involved in defending against different microbes at the mucosal surface, most of these studies have made use of conditional transgenic mice. The present review therefore attempts to provide an overview of the function of ILC3s in infections throughout the body, focusing on their specific activity in different organs.


2021 ◽  
Vol 18 (3) ◽  
pp. 336-344
Author(s):  
V. V. Klimontov ◽  
D. M. Bulumbaeva

The lymphatic system (LS) is one of the main integrative systems of the body, providing protective and transport functions. In recent years, interactions between LS and adipose tissue (AT) have been of particular interest. Lymphatic vessels play an important role in metabolic and regulatory functions of AT, acting as a collector of lipolysis products and adipokines. In its turn, hormones and adipocytokines that produced in adipocytes (including leptin, adiponectin, IL-6, TNF-α, etc.) affect the function of lymphatic endothelial cells and control the growth of lymphatic vessels. Cooperation between LS and AT becomes pathogenetically and clinically important in lymphedema and obesity. It is known that both primary and secondary lymphedema are characterized by increased fat accumulation which is associated with the severity of lymphostasis and inflammation. Similarly, in obesity, the drainage function of LS is impaired, which is accompanied by perilymphatic mononuclear infiltration in the AT. The development of these changes is facilitated by endocrine dysfunction of adipocytes and impaired production of adipocytokines. The increase in the production of inflammatory mediators and the disruption of the traffic of inflammatory cells causes a further deterioration in the outflow of interstitial fluid and exacerbates the inflammation of the AT, thereby forming a vicious circle. The role of lymphangiogenesis in AT remodeling in obesity needs further research. Another promising area of research is the study of the role of intestinal LS in the development of obesity and related disorders. It has been shown that the transport of chylomicrons from the intestine depends on the expression of a number of molecular mediators (VEGF-C, DLL-4, neuropilin-1, VEGFR-1, CD36/FAT, etc.)in the endotheliocytes of the intestinal lymphatic vessels, as well as the functioning of «push-button» and “zippering” junctions between endothelial cells. New approach to the treatment of obesity based on blockade of lymphatic chylomicrontransport has been experimentally substantiated. Further identification of the molecular mechanisms and signaling pathways that determine the remodeling of AT in lymphedema and obesity are likely to provide new approaches to the treatment of these diseases.


2019 ◽  
Vol 19 (17) ◽  
pp. 1491-1511 ◽  
Author(s):  
Shams Aaghaz ◽  
Vivek Gohel ◽  
Ahmed Kamal

Cancer consists of heterogeneous multiple cell subpopulation which at a later stage develop resistant phenotypes, which include resistance to pro-apoptotic stimuli and/or cytotoxic resistance to anticancer compounds. The property of cancerous cells to affect almost any part of the body categorizes cancer to many anatomic and molecular subtypes, each requiring a particular therapeutic intervention. As several modalities are hindered in a variety of cancers and as the cancer cells accrue varied types of oncogenic mutations during their progression the most likely benefit will be obtained by a combination of therapeutic agents that might address the diverse hallmarks of cancer. Natural compounds are the backbone of cancer therapeutics owing to their property of affecting the DNA impairment and restoration mechanisms and also the gene expression modulated via several epigenetic molecular mechanisms. Bioactive peptides isolated from flora and fauna have transformed the arena of antitumour therapy and prompt progress in preclinical studies is promising. The difficulties in creating ACP rest in improving its delivery to the tumour site and it also must maintain a low toxicity profile. The substantial production costs, low selectivity and proteolytic stability of some ACP are some of the factors hindering the progress of peptide drug development. Recently, several publications have tried to edify the field with the idea of using peptides as adjuvants with established drugs for antineoplastic use. This review focuses on peptides from natural sources that precisely target tumour cells and subsequently serve as anticancer agents that are less toxic to normal tissues.


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