Correlation between MDSC and Immune Tolerance in Transplantation: Cytokines, Pathways and Cell-cell Interaction

2019 ◽  
Vol 19 (2) ◽  
pp. 81-92 ◽  
Author(s):  
Tianying Yang ◽  
Jiawei Li ◽  
Ruimin Li ◽  
Chunchen Yang ◽  
Weitao Zhang ◽  
...  

MDSCs play an important role in the induction of immune tolerance. Cytokines and chemokines (GM-CSF, IL-6) contributed to the expansion, accumulation of MDSCs, and MDSCs function through iNOS, arginase and PD-L1. MDSCs are recruited and regulated through JAK/STAT, mTOR and Raf/MEK/ERK signaling pathways. MDSCs’ immunosuppressive functions were realized through Tregs-mediated pathways and their direct suppression of immune cells. All of the above contribute to the MDSC-related immune tolerance in transplantation. MDSCs have huge potential in prolonging graft survival and reducing rejection through different ways and many other factors worthy to be further investigated are also introduced.

2020 ◽  
Vol 21 (11) ◽  
pp. 3897
Author(s):  
Theresa Neuper ◽  
Tobias Frauenlob ◽  
Muamera Sarajlic ◽  
Gernot Posselt ◽  
Silja Wessler ◽  
...  

Helicobacter pylori (H. pylori) is a stomach pathogen that persistently colonizes the gastric mucosa, often leading to chronic inflammation and gastric pathologies. Although infection with H. pylori is the primary risk factor for gastric cancer, the underlying mechanisms of pathogen persistence and consequential chronic inflammation are still not well understood. Conventional dendritic cells (cDCs), which are among the first immune cells to encounter H. pylori in the gastric lining, and the cytokines and chemokines they secrete, contribute to both acute and chronic inflammation. Therefore, this study aimed to unravel the contributions of specific signaling pathways within human CD1c+ cDCs (cDC2s) to the composition of secreted cytokines and chemokines in H. pylori infection. Here, we show that the type IV secretion system (T4SS) plays only a minor role in H. pylori-induced activation of cDC2s. In contrast, Toll-like receptor 4 (TLR4) signaling drives the secretion of inflammatory mediators, including IL-12 and IL-18, while signaling via TLR10 attenuates the release of IL-1β and other inflammatory cytokines upon H. pylori infection. The TLR2 pathway significantly blocks the release of CXCL1 and CXCL8, while it promotes the secretion of TNFα and GM-CSF. Taken together, these results highlight how specific TLR-signaling pathways in human cDC2s shape the H. pylori-induced cytokine and chemokine milieu, which plays a pivotal role in the onset of an effective immune response.


Cancers ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 102 ◽  
Author(s):  
Maria L. Molina ◽  
David García-Bernal ◽  
Salvador Martinez ◽  
Rut Valdor

Glioblastoma (GB) has been shown to up-regulate autophagy with anti- or pro-oncogenic effects. Recently, our group has shown how GB cells aberrantly up-regulate chaperone-mediated autophagy (CMA) in pericytes of peritumoral areas to modulate their immune function through cell-cell interaction and in the tumor’s own benefit. Thus, to understand GB progression, the effect that GB cells could have on autophagy of immune cells that surround the tumor needs to be deeply explored. In this review, we summarize all the latest evidence of several molecular and cellular immunosuppressive mechanisms in the perivascular tumor microenvironment. This immunosuppression has been reported to facilitate GB progression and may be differently modulated by several types of autophagy as a critical point to be considered for therapeutic interventions.


2020 ◽  
Vol 25 (45) ◽  
pp. 4755-4762 ◽  
Author(s):  
Rodrigo Varas ◽  
Fernando C. Ortiz

: Myelin is a specialized membrane allowing for saltatory conduction of action potentials in neurons, an essential process to achieve the normal communication across the nervous system. Accordingly, in diseases characterized by the loss of myelin and myelin forming cells -oligodendrocytes in the CNS-, patients show severe neurological disabilities. After a demyelinated insult, microglia, astrocytes and oligodendrocyte precursor cells invade the lesioned area initiating a spontaneous process of myelin repair (i.e. remyelination). A preserved hallmark of this neuroinflammatory scenario is a local increase of oxidative stress, where several cytokines and chemokines are released by glial and other cells. This generates an environment that determines cell interaction resulting in oligodendrocyte maturity and the ability to synthesize new myelin. Herein we review the main features of the regulatory aspect of these molecules based on recent findings and propose new putative signal molecules involved in the remyelination process, focused in the etiology of Multiple Sclerosis, one of the main demyelinating diseases causing disabilities in the population.


Author(s):  
Thea Magrone ◽  
Manrico Magrone ◽  
Matteo Antonio Russo ◽  
Emilio Jirillo

Background: Platelets are cellular fragments derived from bone-marrow megacaryocytes and they are mostly involved in haemostasis and coagulation. However, according to recent data, platelets are able to perform novel immune functions. In fact, they possess a receptorial armamentarium on their membrane for interacting with innate and adaptive immune cells. In addition, platelets also secrete granules which contain cytokines and chemokines for activating and recruiting even distant immune cells. Objectives: The participation of platelets in inflammatory processes will be discussed also in view of their dual role in terms of triggering or resolving inflammation. Involvement of platelets in disease will be illustrated, pointing to their versatile function to either up- or down-regulate pathological mechanisms. Finally, despite the availability of some anti-platelet agents, such as aspirin, dietary manipulation of platelet function is currently investigated. In this regard, special emphasis will be placed on dietary omega-3 polyunsaturated fatty acids (PUFAs) and polyphenol effects on platelets. Conclusion: Platelets play a dual role in inflammatory-immune-mediated diseases either activating or deactivating immune cells. Diet based on substances, such as omega-3 PUFAs and polyphenols, may act as a modulator of platelet function, even if more clinical trials are needed to corroborate such a contention.


Author(s):  
Orkide Palabiyik ◽  
Ebru Tastekin ◽  
Zeynep Doganlar ◽  
Pinar Tayfur ◽  
Ayten Dogan ◽  
...  

Molecules ◽  
2021 ◽  
Vol 26 (8) ◽  
pp. 2278
Author(s):  
Afshin Derakhshani ◽  
Zeinab Rostami ◽  
Hossein Safarpour ◽  
Mahdi Abdoli Shadbad ◽  
Niloufar Sadat Nourbakhsh ◽  
...  

Over the past decade, there have been remarkable advances in understanding the signaling pathways involved in cancer development. It is well-established that cancer is caused by the dysregulation of cellular pathways involved in proliferation, cell cycle, apoptosis, cell metabolism, migration, cell polarity, and differentiation. Besides, growing evidence indicates that extracellular matrix signaling, cell surface proteoglycans, and angiogenesis can contribute to cancer development. Given the genetic instability and vast intra-tumoral heterogeneity revealed by the single-cell sequencing of tumoral cells, the current approaches cannot eliminate the mutating cancer cells. Besides, the polyclonal expansion of tumor-infiltrated lymphocytes in response to tumoral neoantigens cannot elicit anti-tumoral immune responses due to the immunosuppressive tumor microenvironment. Nevertheless, the data from the single-cell sequencing of immune cells can provide valuable insights regarding the expression of inhibitory immune checkpoints/related signaling factors in immune cells, which can be used to select immune checkpoint inhibitors and adjust their dosage. Indeed, the integration of the data obtained from the single-cell sequencing of immune cells with immune checkpoint inhibitors can increase the response rate of immune checkpoint inhibitors, decrease the immune-related adverse events, and facilitate tumoral cell elimination. This study aims to review key pathways involved in tumor development and shed light on single-cell sequencing. It also intends to address the shortcomings of immune checkpoint inhibitors, i.e., their varied response rates among cancer patients and increased risk of autoimmunity development, via applying the data from the single-cell sequencing of immune cells.


2021 ◽  
Vol 22 (5) ◽  
pp. 2578
Author(s):  
Trim Lajqi ◽  
Christian Marx ◽  
Hannes Hudalla ◽  
Fabienne Haas ◽  
Silke Große ◽  
...  

Microglia, the innate immune cells of the CNS, exhibit long-term response changes indicative of innate immune memory (IIM). Our previous studies revealed IIM patterns of microglia with opposing immune phenotypes: trained immunity after a low dose and immune tolerance after a high dose challenge with pathogen-associated molecular patterns (PAMP). Compelling evidence shows that innate immune cells adopt features of IIM via immunometabolic control. However, immunometabolic reprogramming involved in the regulation of IIM in microglia has not been fully addressed. Here, we evaluated the impact of dose-dependent microglial priming with ultra-low (ULP, 1 fg/mL) and high (HP, 100 ng/mL) lipopolysaccharide (LPS) doses on immunometabolic rewiring. Furthermore, we addressed the role of PI3Kγ on immunometabolic control using naïve primary microglia derived from newborn wild-type mice, PI3Kγ-deficient mice and mice carrying a targeted mutation causing loss of lipid kinase activity. We found that ULP-induced IIM triggered an enhancement of oxygen consumption and ATP production. In contrast, HP was followed by suppressed oxygen consumption and glycolytic activity indicative of immune tolerance. PI3Kγ inhibited glycolysis due to modulation of cAMP-dependent pathways. However, no impact of specific PI3Kγ signaling on immunometabolic rewiring due to dose-dependent LPS priming was detected. In conclusion, immunometabolic reprogramming of microglia is involved in IIM in a dose-dependent manner via the glycolytic pathway, oxygen consumption and ATP production: ULP (ultra-low-dose priming) increases it, while HP reduces it.


Cells ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 1004
Author(s):  
Sonia Kiran ◽  
Vijay Kumar ◽  
Santosh Kumar ◽  
Robert L Price ◽  
Udai P. Singh

Obesity is characterized as a complex and multifactorial excess accretion of adipose tissue (AT) accompanied with alterations in the immune response that affects virtually all age and socioeconomic groups around the globe. The abnormal accumulation of AT leads to several metabolic diseases, including nonalcoholic fatty liver disorder (NAFLD), low-grade inflammation, type 2 diabetes mellitus (T2DM), cardiovascular disorders (CVDs), and cancer. AT is an endocrine organ composed of adipocytes and immune cells, including B-Cells, T-cells and macrophages. These immune cells secrete various cytokines and chemokines and crosstalk with adipokines to maintain metabolic homeostasis and low-grade chronic inflammation. A novel form of adipokines, microRNA (miRs), is expressed in many developing peripheral tissues, including ATs, T-cells, and macrophages, and modulates the immune response. miRs are essential for insulin resistance, maintaining the tumor microenvironment, and obesity-associated inflammation (OAI). The abnormal regulation of AT, T-cells, and macrophage miRs may change the function of different organs including the pancreas, heart, liver, and skeletal muscle. Since obesity and inflammation are closely associated, the dysregulated expression of miRs in inflammatory adipocytes, T-cells, and macrophages suggest the importance of miRs in OAI. Therefore, in this review article, we have elaborated the role of miRs as epigenetic regulators affecting adipocyte differentiation, immune response, AT browning, adipogenesis, lipid metabolism, insulin resistance (IR), glucose homeostasis, obesity, and metabolic disorders. Further, we will discuss a set of altered miRs as novel biomarkers for metabolic disease progression and therapeutic targets for obesity.


2021 ◽  
pp. 1-15
Author(s):  
Ping Xu ◽  
Xiao Mo ◽  
Ruixue Xia ◽  
Long Jiang ◽  
Chengfei Zhang ◽  
...  

BACKGROUND: Potassium channels, encoded by more than seventy genes, are cell excitability transmembrane proteins and become evident to play essential roles in tumor biology. OBJECTIVE: The deregulation of potassium channel genes has been related to cancer development and patient prognosis. The objective of this study is to understand the role of potassium channels in lung cancer. METHODS: We examined all potassium channel genes and identified that KCNN4 is the most significantly overexpressed one in lung adenocarcinoma. The role and mechanism of KCNN4 in lung adenocarcinoma were further investigated by in vitro cell and molecular assay and in vivo mouse xenograft models. RESULTS: We revealed that the silencing of KCNN4 significantly inhibits cell proliferation, migration, invasion, and tumorigenicity of lung adenocarcinoma. Further studies showed that knockdown of KCNN4 promotes cell apoptosis, induces cell cycle arrested in the S phase, and is associated with the epithelial to mesenchymal transition (EMT) process. Most importantly, we demonstrated that KCNN4 regulates the progression of lung adenocarcinoma through P13K/AKT and MEK/ERK signaling pathways. The use of inhibitors that targeted AKT and ERK also significantly inhibit the proliferation and metastasis of lung adenocarcinoma cells. CONCLUSIONS: This study investigated the function and mechanism of KCNN4 in lung adenocarcinoma. On this basis, this means that KCNN4 can be used as a tumor marker for lung adenocarcinoma and is expected to become an important target for a potential drug.


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