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Signal Transduction and Targeted Therapy Nov 2020Emerging evidence suggests that Toll-like receptors (TLRs) ligands pretreatment may play a vital role in the progress of myocardial ischemia/reperfusion (I/R) injury. As...
Emerging evidence suggests that Toll-like receptors (TLRs) ligands pretreatment may play a vital role in the progress of myocardial ischemia/reperfusion (I/R) injury. As the ligand of TLR3, polyinosinic-polycytidylic acid (poly(I:C)), a synthetic double-stranded RNA, whether its preconditioning can exhibit a cardioprotective phenotype remains unknown. Here, we report the protective effect of poly(I:C) pretreatment in acute myocardial I/R injury by activating TLR3/PI3K/Akt signaling pathway. Poly(I:C) pretreatment leads to a significant reduction of infarct size, improvement of cardiac function, and downregulation of inflammatory cytokines and apoptotic molecules compared with controls. Subsequently, our data demonstrate that phosphorylation of TLR3 tyrosine residue and its interaction with PI3K is enhanced, and protein levels of phospho-PI3K and phospho-Akt are both increased after poly(I:C) pretreatment, while knock out of TLR3 suppresses the cardioprotection of poly(I:C) preconditioning through a decreased activation of PI3K/Akt signaling. Moreover, inhibition of p85 PI3K by the administration of LY294002 in vivo and knockdown of Akt by siRNA in vitro significantly abolish poly(I:C) preconditioning-induced cardioprotective effect. In conclusion, our results reveal that poly(I:C) preconditioning exhibits essential protection in myocardial I/R injury via its modulation of TLR3, and the downstream PI3K/Akt signaling, which may provide a potential pharmacologic target for perioperative cardioprotection.
Topics: Animals; Mice; Mice, Knockout; Myocardial Reperfusion Injury; Phosphatidylinositol 3-Kinases; Poly I-C; Proto-Oncogene Proteins c-akt; Signal Transduction; Toll-Like Receptor 3
PubMed: 33154351
DOI: 10.1038/s41392-020-00257-w -
Cell Reports Aug 2023Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are severe clinical disorders that mainly develop from viral respiratory infections, sepsis, and...
Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are severe clinical disorders that mainly develop from viral respiratory infections, sepsis, and chest injury. Antigen-presenting cells play a pivotal role in propagating uncontrolled inflammation and injury through the excess secretion of pro-inflammatory cytokines and recruitment of immune cells. Autophagy, a homeostatic process that involves the degradation of cellular components, is involved in many processes including lung inflammation. Here, we use a polyinosinic-polycytidylic acid (poly(I:C))-induced lung injury mouse model to mimic viral-induced ALI/ARDS and show that disruption of autophagy in macrophages exacerbates lung inflammation and injury, whereas autophagy induction attenuates this process. Therefore, induction of autophagy in macrophages can be a promising therapeutic strategy in ALI/ARDS.
Topics: Animals; Mice; Antigen-Presenting Cells; Macrophages; Autophagy; Acute Lung Injury; Poly I-C; Respiratory Distress Syndrome
PubMed: 37590140
DOI: 10.1016/j.celrep.2023.112990 -
Frontiers in Immunology 2020Tumor-associated macrophages (TAMs), with M2-like immunosuppressive profiles, are key players in the development and dissemination of tumors. Hence, the induction of M1...
Tumor-associated macrophages (TAMs), with M2-like immunosuppressive profiles, are key players in the development and dissemination of tumors. Hence, the induction of M1 pro-inflammatory and anti-tumoral states is critical to fight against cancer cells. The activation of the endosomal toll-like receptor 3 by its agonist poly(I:C) has shown to efficiently drive this polarization process. Unfortunately, poly(I:C) presents significant systemic toxicity, and its clinical use is restricted to a local administration. Therefore, the objective of this work has been to facilitate the delivery of poly(I:C) to macrophages through the use of nanotechnology, that will ultimately drive their phenotype toward pro-inflammatory states. Poly(I:C) was complexed to arginine-rich polypeptides, and then further enveloped with an anionic polymeric layer either by film hydration or incubation. Physicochemical characterization of the nanocomplexes was conducted by dynamic light scattering and transmission electron microscopy, and poly(I:C) association efficiency by gel electrophoresis. Primary human-derived macrophages were used as relevant cell model. Alamar Blue assay, ELISA, PCR and flow cytometry were used to determine macrophage viability, polarization, chemokine secretion and uptake of nanocomplexes. The cytotoxic activity of pre-treated macrophages against PANC-1 cancer cells was assessed by flow cytometry. The final poly(I:C) nanocomplexes presented sizes lower than 200 nm, with surface charges ranging from +40 to -20 mV, depending on the envelopment. They all presented high poly(I:C) loading values, from 12 to 50%, and great stability in cell culture media. , poly(I:C) nanocomplexes were highly taken up by macrophages, in comparison to the free molecule. Macrophage treatment with these nanocomplexes did not reduce their viability and efficiently stimulated the secretion of the T-cell recruiter chemokines CXCL10 and CCL5, of great importance for an effective anti-tumor immune response. Finally, poly(I:C) nanocomplexes significantly increased the ability of treated macrophages to directly kill cancer cells. Overall, these enveloped poly(I:C) nanocomplexes might represent a therapeutic option to fight cancer through the induction of cytotoxic M1-polarized macrophages.
Topics: Arginine; Cell Differentiation; Humans; Macrophage Activation; Nanoparticles; Poly I-C; Tumor-Associated Macrophages
PubMed: 32733469
DOI: 10.3389/fimmu.2020.01412 -
Journal of Neurochemistry Dec 2022Inflammation associated with viral infection of the nervous system has been involved in the pathogenesis of neurodegenerative diseases, such as Alzheimer's disease (AD)...
Inflammation associated with viral infection of the nervous system has been involved in the pathogenesis of neurodegenerative diseases, such as Alzheimer's disease (AD) and multiple sclerosis. Polyinosinic:polycytidylic acid (poly[I:C]) is a Toll-like receptor 3 (TLR3) agonist that mimics the inflammatory response to systemic viral infections. Despite growing recognition of the role of glial cells in AD pathology, their involvement in the accumulation and clearance of amyloid β (Aβ) in the brain of patients with AD is poorly understood. Neprilysin (NEP) and insulin-degrading enzyme (IDE) are the main Aβ-degrading enzymes in the brain. This study investigated whether poly(I:C) regulated Aβ degradation and neurotoxicity by modulating NEP and IDE protein levels through TLR3 in astrocytes. To this aim, primary rat primary astrocyte cultures were treated with poly(I:C) and inhibitors of the TLR3 signaling. Protein levels were assessed by Western blot. Aβ toxicity to primary neurons was measured by lactate dehydrogenase release. Poly(I:C) induced a significant decrease in NEP levels on the membrane of astrocytes as well as in the culture medium. The degradation of exogenous Aβ was markedly delayed in poly(I:C)-treated astrocytes. This delay significantly increased the neurotoxicity of exogenous Aβ1-42. Altogether, these results suggest that viral infections induce Aβ neurotoxicity by decreasing NEP levels in astrocytes and consequently preventing Aβ degradation.
Topics: Animals; Rats; Alzheimer Disease; Amyloid beta-Peptides; Astrocytes; Insulysin; Neprilysin; Toll-Like Receptor 3; Poly I-C; Virus Diseases
PubMed: 36321194
DOI: 10.1111/jnc.15716 -
Scientific Reports Nov 2023Proinflammatory cytokine interleukin (IL)-6 was associated with disease severity in patients with COVID-19. The mechanism underlying the excessive IL-6 production by...
Proinflammatory cytokine interleukin (IL)-6 was associated with disease severity in patients with COVID-19. The mechanism underlying the excessive IL-6 production by SARS-Cov-2 infection remains unclear. Respiratory viruses initially infect nasal or bronchial epithelial cells that produce various inflammatory mediators. Here, we show that pretreatment of human bronchial epithelial cells (NCl-H292) with interferon (IFN)-γ (10 ng/mL) markedly increased IL-6 production induced by the toll-like receptor (TLR) 3 agonist poly(I:C) (1 µg/mL) from 0.4 ± 0.1 to 4.1 ± 0.4 ng/mL (n = 3, P < 0.01). A similar effect was observed in human alveolar A549 and primary bronchial epithelial cells. TLR3 knockdown using siRNA in NCl-H292 cells diminished the priming effects of IFN-γ on poly(I:C)-induced IL-6 production. Furthermore, the Janus kinase (JAK) inhibitor tofacitinib (1 µM) inhibited IFN-γ-induced upregulation of TLR3, and suppressed poly(I:C)-induced IL-6 production. Quantitative chromatin immunoprecipitation revealed that IFN-γ stimulated histone modifications at the IL-6 gene locus. Finally, IFN-γ priming significantly increased lung IL-6 mRNA and protein levels in poly(I:C)-administrated mice. Thus, priming bronchial epithelial cells with IFN-γ increases poly(I:C)-induced IL-6 production via JAK-dependent TLR3 upregulation and chromatin remodeling at the IL-6 gene locus. These mechanisms may be involved in severe respiratory inflammation following infection with RNA viruses.
Topics: Animals; Humans; Mice; Epithelial Cells; Interferon-gamma; Interleukin-6; Interleukin-8; Poly I-C; Toll-Like Receptor 3
PubMed: 38030681
DOI: 10.1038/s41598-023-48422-9 -
Neurochemical Research Sep 2017Microglia, the resident immune cells of the CNS, are primary regulators of the neuroimmune response to injury. Type I interferons (IFNs), including the IFNαs and IFNβ,... (Review)
Review
Microglia, the resident immune cells of the CNS, are primary regulators of the neuroimmune response to injury. Type I interferons (IFNs), including the IFNαs and IFNβ, are key cytokines in the innate immune system. Their activity is implicated in the regulation of microglial function both during development and in response to neuroinflammation, ischemia, and neurodegeneration. Data from numerous studies in multiple sclerosis (MS) and stroke suggest that type I IFNs can modulate the microglial phenotype, influence the overall neuroimmune milieu, regulate phagocytosis, and affect blood-brain barrier integrity. All of these IFN-induced effects result in numerous downstream consequences on white matter pathology and microglial reactivity. Dysregulation of IFN signaling in mouse models with genetic deficiency in ubiquitin specific protease 18 (USP18) leads to a severe neurological phenotype and neuropathological changes that include white matter microgliosis and pro-inflammatory gene expression in dystrophic microglia. A class of genetic disorders in humans, referred to as pseudo-TORCH syndrome (PTS) for the clinical resemblance to infection-induced TORCH syndrome, also show dysregulation of IFN signaling, which leads to severe neurological developmental disease. In these disorders, the excessive activation of IFN signaling during CNS development results in a destructive interferonopathy with similar induction of microglial dysfunction as seen in USP18 deficient mice. Other recent studies implicate "microgliopathies" more broadly in neurological disorders including Alzheimer's disease (AD) and MS, suggesting that microglia are a potential therapeutic target for disease prevention and/or treatment, with interferon signaling playing a key role in regulating the microglial phenotype.
Topics: Animals; Humans; Interferon Inducers; Interferon Type I; Microglia; Nervous System Diseases; Poly I-C; Signal Transduction; White Matter
PubMed: 28540600
DOI: 10.1007/s11064-017-2307-8 -
The Journal of Neuroscience : the... Mar 2019Maternal immune activation (MIA) is a principal environmental risk factor contributing to autism spectrum disorder (ASD), which compromises fetal brain development at...
Maternal immune activation (MIA) is a principal environmental risk factor contributing to autism spectrum disorder (ASD), which compromises fetal brain development at critical periods of pregnancy and might be causally linked to ASD symptoms. We report that endogenous activation of the purinergic ion channel P2X7 (P2rx7) is necessary and sufficient to transduce MIA to autistic phenotype in male offspring. MIA induced by poly(I:C) injections to P2rx7 WT mouse dams elicited an autism-like phenotype in their offspring, and these alterations were not observed in P2rx7-deficient mice, or following maternal treatment with a specific P2rx7 antagonist, JNJ47965567. Genetic deletion and pharmacological inhibition of maternal P2rx7s also counteracted the induction of IL-6 in the maternal plasma and fetal brain, and disrupted brain development, whereas postnatal P2rx7 inhibition alleviated behavioral and morphological alterations in the offspring. Administration of ATP to P2rx7 WT dams also evoked autistic phenotype, but not in KO dams, implying that P2rx7 activation by ATP is sufficient to induce autism-like features in offspring. Our results point to maternal and offspring P2rx7s as potential therapeutic targets for the early prevention and treatment of ASD. Autism spectrum disorder (ASD) is a neurodevelopmental psychiatric disorder caused by genetic and environmental factors. Recent studies highlighted the importance of perinatal risks, in particular, maternal immune activation (MIA), showing strong association with the later emergence of ASD in the affected children. MIA could be mimicked in animal models via injection of a nonpathogenic agent poly(I:C) during pregnancy. This is the first report showing the key role of a ligand gated ion channel, the purinergic P2X7 receptor in MIA-induced autism-like behavioral and biochemical features. We show that genetic or pharmacological inhibition of both maternal and offspring P2X7 receptors could reverse the compromised brain development and autistic phenotype pointing to new possibilities for prevention and treatment of ASD.
Topics: Animals; Autism Spectrum Disorder; Cerebellum; Cytokines; Disease Models, Animal; Female; Male; Mice, Inbred C57BL; Mice, Knockout; Poly I-C; Pregnancy; Prenatal Exposure Delayed Effects; Receptors, Purinergic P2X7
PubMed: 30683682
DOI: 10.1523/JNEUROSCI.1895-18.2019 -
Scientific Reports May 2023Most individuals with neurodevelopmental disorders (NDDs), including schizophrenia and autism spectrum disorders, experience disruptions in sleep and circadian rhythms....
Most individuals with neurodevelopmental disorders (NDDs), including schizophrenia and autism spectrum disorders, experience disruptions in sleep and circadian rhythms. Epidemiological studies indicate that exposure to prenatal infection increases the risk of developing NDDs. We studied how environmental circadian disruption contributes to NDDs using maternal immune activation (MIA) in mice, which models prenatal infection. Pregnant dams were injected with viral mimetic poly IC (or saline) at E9.5. Adult poly IC- and saline-exposed offspring were subjected to 4 weeks of each of the following: standard lighting (LD1), constant light (LL) and standard lighting again (LD2). Behavioral tests were conducted in the last 12 days of each condition. Poly IC exposure led to significant behavioral differences, including reduced sociability (males only) and deficits in prepulse inhibition. Interestingly, poly IC exposure led to reduced sociability specifically when males were tested after LL exposure. Mice were exposed again to either LD or LL for 4 weeks and microglia were characterized. Notably, poly IC exposure led to increased microglial morphology index and density in dentate gyrus, an effect attenuated by LL exposure. Our findings highlight interactions between circadian disruption and prenatal infection, which has implications in informing the development of circadian-based therapies for individuals with NDDs.
Topics: Pregnancy; Female; Male; Humans; Mice; Animals; Prenatal Exposure Delayed Effects; Poly I-C; Prepulse Inhibition; Schizophrenia; Behavior, Animal; Disease Models, Animal
PubMed: 37179433
DOI: 10.1038/s41598-023-34363-w -
BMC Immunology Apr 2017Delayed wound healing reduces the quality of life (QOL) of patients. Thus, understanding the mechanism of wound healing is indispensable for better management. However,...
BACKGROUND
Delayed wound healing reduces the quality of life (QOL) of patients. Thus, understanding the mechanism of wound healing is indispensable for better management. However, the role of innate immunity in wound healing is thus far unknown. Recently the involvement of TLR3 in wound healing has been evaluated. The systemic administration of polyriboinosinic-polyribocytidylic acid (poly I:C ; a substitute for viral dsRNA and a ligand of toll-like receptor 3), enhances wound healing in vivo. The aim of this study is to improve our understanding of the link between innate immunity and human wound healing, particularly in re-epithelialization.
RESULTS
The present study showed that poly I:C significantly accelerated collective HaCaT cell migration in a scratch assay. Poly I:C also increased IL-8 and bFGF production, and anti-IL-8 antibodies significantly inhibited the migration caused by poly I:C. Human recombinant IL-8 also accelerated collective HaCaT cell migration. An immunofluorescence assay and enzyme-linked immunosorbent assay (ELISA) also revealed that poly I:C decreased E-cadherin protein levels and increased vimentin protein levels, and anti-IL-8 antibody reversed this effect. In contrast, nucleic/cytosolic protein ratios of Snail 1 were unchanged in all tested conditions.
CONCLUSION
Our findings demonstrated that poly I:C accelerated collective HaCaT cell migration via autocrine/paracrine secretions of IL-8 and the subsequent incomplete epithelial-mesenchymal transition (EMT). Our findings provide a new strategy for wound healing by regulating innate immune systems in re-epithelialization.
Topics: Antibodies, Blocking; Cadherins; Cell Line; Cell Movement; DNA, Viral; Epithelial-Mesenchymal Transition; Humans; Immunity, Innate; Interleukin-8; Keratinocytes; Poly I-C; Snail Family Transcription Factors; Toll-Like Receptor 3; Vimentin; Wound Healing
PubMed: 28438134
DOI: 10.1186/s12865-017-0202-3 -
Advanced Science (Weinheim,... Nov 2023The efficient activation of professional antigen-presenting cells-such as dendritic cells (DC)-in tumors and lymph nodes is critical for the design of next-generation...
The efficient activation of professional antigen-presenting cells-such as dendritic cells (DC)-in tumors and lymph nodes is critical for the design of next-generation cancer vaccines and may be able to provide anti-tumor effects by itself through immune stimulation. The challenge is to stimulate these cells without causing excessive toxicity. It is hypothesized that a multi-pronged combinatorial approach to DC stimulation would allow dose reductions of innate immune receptor-stimulating TLR3 agonists while enhancing drug efficacy. Here, a hybrid lipid nanoparticle (LNP) platform is developed and tested for double-stranded RNA (polyinosinic:polycytidylic acid for TLR3 agonism) and immune modulator (L-CANDI) delivery. This study shows that the ≈120 nm hybrid nanoparticles-in-nanoparticles effectively eradicate tumors by themselves and generate long-lasting, durable anti-tumor immunity in mouse models.
Topics: Animals; Mice; Toll-Like Receptor 3; Poly I-C; Cancer Vaccines; Neoplasms; Dendritic Cells
PubMed: 37814359
DOI: 10.1002/advs.202303576