scholarly journals M. tuberculosis infection of human iPSC-derived macrophages reveals complex membrane dynamics during xenophagy evasion

2020 ◽  
Vol 134 (5) ◽  
pp. jcs252973
Author(s):  
Elliott M. Bernard ◽  
Antony Fearns ◽  
Claudio Bussi ◽  
Pierre Santucci ◽  
Christopher J. Peddie ◽  
...  
Keyword(s):  
Inflammatory Responses ◽  
Ion Beam ◽  
Induced Pluripotent Stem Cell ◽  
Membrane Dynamics ◽  
Live Cell ◽  
Initiation Factor ◽  
Human Macrophage ◽  
Transcriptional Responses ◽  
Macrophage Response ◽  
Human Macrophages

ABSTRACTXenophagy is an important cellular defence mechanism against cytosol-invading pathogens, such as Mycobacterium tuberculosis (Mtb). Activation of xenophagy in macrophages targets Mtb to autophagosomes; however, how Mtb is targeted to autophagosomes in human macrophages at a high spatial and temporal resolution is unknown. Here, we use human induced pluripotent stem cell-derived macrophages (iPSDMs) to study the human macrophage response to Mtb infection and the role of the ESX-1 type VII secretion system. Using RNA-seq, we identify ESX-1-dependent transcriptional responses in iPSDMs after infection with Mtb. This analysis revealed differential inflammatory responses and dysregulated pathways such as eukaryotic initiation factor 2 (eIF2) signalling and protein ubiquitylation. Moreover, live-cell imaging revealed that Mtb infection in human macrophages induces dynamic ESX-1-dependent, LC3B-positive tubulovesicular autophagosomes (LC3-TVS). Through a correlative live-cell and focused ion beam scanning electron microscopy (FIB SEM) approach, we show that upon phagosomal rupture, Mtb induces the formation of LC3-TVS, from which the bacterium is able to escape to reside in the cytosol. Thus, iPSDMs represent a valuable model for studying spatiotemporal dynamics of human macrophage–Mtb interactions, and Mtb is able to evade capture by autophagic compartments.

scholarly journals 5-HT2Bserotonin receptor agonist BW723C86 shapes the macrophage gene profile via AhR and impairs monocyte-to-osteoclast differentiation

2019 ◽  
Author(s):  
Concha Nieto ◽  
Ignacio Rayo ◽  
Mateo de las Casas-Engel ◽  
Elena Izquierdo ◽  
Bárbara Alonso ◽  
...  
Keyword(s):  
Aryl Hydrocarbon Receptor ◽  
Selective Serotonin Reuptake Inhibitors ◽  
Inflammatory Responses ◽  
Osteoclast Differentiation ◽  
Human Macrophage ◽  
List Type ◽  
Human Macrophages ◽  
Aryl Hydrocarbon ◽  
Anti Inflammatory ◽  
Independent Effects

ABSTRACTPeripheral serotonin (5-HT) exacerbates or limits inflammatory pathologies through interaction with seven types of 5-HT receptors (5-HT1-7). As central regulators of inflammation, macrophages are critical targets of 5-HT, which promotes their anti-inflammatory and pro-fibrotic polarization primarily via the 5-HT7-Protein Kinase A (PKA) axis. However, anti-inflammatory human macrophages are also characterized by the expression of 5-HT2B, an off-target of anesthetics, anti-parkinsonian drugs and Selective Serotonin Reuptake Inhibitors (SSRI) that contributes to 5-HT-mediated pathologies. Since 5-HT2Bprevents mononuclear phagocyte degeneration in amyotrophic lateral sclerosis and modulates motility of murine microglial processes, we sought to determine the functional and transcriptional consequences of 5-HT2Bactivation in human macrophages. Ligation of 5-HT2Bby the 5-HT2B-specific agonist BW723C86, which exhibits antidepressant- and anxiolytic-like effects in animal models, significantly modified the cytokine profile and the transcriptional signature in macrophages. Importantly, 5-HT2Bagonist-induced transcriptional changes were partly mediated through activation of the Aryl hydrocarbon Receptor (AhR), a ligand-dependent transcription factor that regulates immune responses and the biological responses to xenobiotics. Besides, BW723C86 triggered transcriptional effects that could not be abrogated by 5-HT2Bantagonists and impaired monocyte-to-osteoclast differentiation by affecting the expression of negative (IRF8) and positive (PRDM1) regulators of osteoclastogenesis. Therefore, our results demonstrate the existence of a functional 5-HT2B-AhR axis in human macrophages and indicate that the commonly used 5-HT2Bagonist BW723C86 exhibits 5-HT2B-independent effects. The 5-HT2B-AhR link extends the range of signaling pathways initiated upon 5-HT receptor engagement and identifies a point of convergence for endogenous and exogenous agents with ability to modulate inflammatory responses.KEY POINTS-The serotonin receptor 5-HT2Bmodifies the human macrophage transcriptome through activation of the Aryl Hydrocarbon Receptor.-BW723C86, an agonist used for 5-HT2Bactivationin vivo, exerts 5-HT2B-independent effects and limits monocyte osteoclastogenic potential.

scholarly journals Differential Modulation of the Phospholipidome of Proinflammatory Human Macrophages by the Flavonoids Quercetin, Naringin and Naringenin

Molecules ◽  
2020 ◽  
Vol 25 (15) ◽  
pp. 3460
Author(s):  
Tiago A. Conde ◽  
Luís Mendes ◽  
Vítor M. Gaspar ◽  
João F. Mano ◽  
Tânia Melo ◽  
...  
Keyword(s):  
Inflammatory Responses ◽  
Human Macrophage ◽  
Immunomodulatory Activity ◽  
Differential Modulation ◽  
Immunomodulatory Effects ◽  
Human Macrophages ◽  
Future Studies ◽  
Ifn Γ ◽  
Unique Signature

The immunomodulatory activity of flavonoids is increasingly appreciated. Macrophage phospholipids (PLs) play crucial roles in cell-mediated inflammatory responses. However, little is known on how these PLs are affected upon flavonoid treatment. In this work, we have used mass-spectrometry-based lipidomics to characterize the changes in the phospholipidome of proinflammatory human-macrophage-like cells (THP-1-derived and LPS+IFN-γ-stimulated) incubated with non-cytotoxic concentrations of three flavonoids: quercetin, naringin and naringenin. One hundred forty-seven PL species belonging to various classes were identified, and their relative abundances were determined. Each flavonoid displayed its own unique signature of induced effects. Quercetin produced the strongest impact, acting both on constitutive PLs (phosphatidylcholines, phosphatidylethanolamines and sphingomyelins) and on minor signaling lipids, such as phosphatidylinositol (PI) and phosphatidylserine (PS) species. Conversely, naringin hardly affected structural PLs, producing changes in signaling molecules that were opposite to those seen in quercetin-treated macrophages. In turn, albeit sharing some effects with quercetin, naringenin did not change PI and PS levels and interfered with a set of phosphatidylcholines distinct from those modulated by quercetin. These results demonstrate that flavonoids bioactivity involves profound and specific remodeling of macrophage phospholipidome, paving the way to future studies on the role of cellular phospholipids in flavonoid-mediated immunomodulatory effects.

scholarly journals ACVR1R206H extends inflammatory responses in human induced pluripotent stem cell-derived macrophages

Bone ◽  
2021 ◽  
pp. 116129
Author(s):  
Koji Matsuo ◽  
Abigail Lepinski ◽  
Robert D. Chavez ◽  
Emilie Barruet ◽  
Ashley Pereira ◽  
...  
Keyword(s):  
Stem Cell ◽  
Pluripotent Stem Cell ◽  
Inflammatory Responses ◽  
Induced Pluripotent Stem Cell ◽  
Induced Pluripotent

scholarly journals Growth Arrest-Specific Factor 6 (GAS6) Is Increased in COVID-19 Patients and Predicts Clinical Outcome

Biomedicines ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 335
Author(s):  
Albert Morales ◽  
Silvia Rojo Rello ◽  
Helena Cristóbal ◽  
Aida Fiz-López ◽  
Elisa Arribas ◽  
...  
Keyword(s):  
Inflammatory Responses ◽  
Growth Arrest ◽  
Emergency Admission ◽  
Human Macrophage ◽  
Specific Factor ◽  
Alveolar Cells ◽  
Lps Challenge ◽  
Tam Receptors ◽  
Relevant Role ◽  
Severity Of The Disease

Background: Growth arrest-specific factor 6 (GAS6) and the Tyro3, AXL, and MERTK (TAM) receptors counterbalance pro-inflammatory responses. AXL is a candidate receptor for SARS-CoV-2, particularly in the respiratory system, and the GAS6/AXL axis is targeted in current clinical trials against COVID-19. However, GAS6 and TAMs have not been evaluated in COVID-19 patients at emergency admission. Methods: Plasma GAS6, AXL, and MERTK were analyzed in 132 patients consecutively admitted to the emergency ward during the first peak of COVID-19. Results: GAS6 levels were higher in the SARS-CoV-2-positive patients, increasing progressively with the severity of the disease. Patients with initial GAS6 at the highest quartile had the worst outcome, with a 3-month survival of 65%, compared to a 90% survival for the rest. Soluble AXL exhibited higher plasma concentration in deceased patients, without significant differences in MERTK among SARS-CoV-2-positive groups. GAS6 mRNA was mainly expressed in alveolar cells and AXL in airway macrophages. Remarkably, THP-1 human macrophage differentiation neatly induces AXL, and its inhibition (bemcentinib) reduced cytokine production in human macrophages after LPS challenge. Conclusions: Plasma GAS6 and AXL levels reflect COVID-19 severity and could be early markers of disease prognosis, supporting a relevant role of the GAS6/AXL system in the immune response in COVID-19.

scholarly journals Therapeutics potentiating microglial p21-Nrf2 axis can rescue neurodegeneration caused by neuroinflammation

2020 ◽  
Vol 6 (46) ◽  
pp. eabc1428
Author(s):  
A. Nakano-Kobayashi ◽  
A. Fukumoto ◽  
A. Morizane ◽  
D. T. Nguyen ◽  
T. M. Le ◽  
...  
Keyword(s):  
Neurodegenerative Disorders ◽  
Inflammatory Responses ◽  
Therapeutic Potential ◽  
Neuronal Survival ◽  
Disease Model ◽  
Neuronal Loss ◽  
Induced Pluripotent Stem Cell ◽  
Related Factor ◽  
Induced Pluripotent ◽  
Novel Therapeutic

Neurodegenerative disorders are caused by progressive neuronal loss, and there is no complete treatment available yet. Neuroinflammation is a common feature across neurodegenerative disorders and implicated in the progression of neurodegeneration. Dysregulated activation of microglia causes neuroinflammation and has been highlighted as a treatment target in therapeutic strategies. Here, we identified novel therapeutic candidate ALGERNON2 (altered generation of neurons 2) and demonstrate that ALGERNON2 suppressed the production of proinflammatory cytokines and rescued neurodegeneration in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)–induced Parkinson’s disease model. ALGERNON2 stabilized cyclinD1/p21 complex, leading to up-regulation of nuclear factor erythroid 2–related factor 2 (Nrf2), which contributes to antioxidative and anti-inflammatory responses. Notably, ALGERNON2 enhanced neuronal survival in other neuroinflammatory conditions such as the transplantation of induced pluripotent stem cell–derived dopaminergic neurons into murine brains. In conclusion, we present that the microglial potentiation of the p21-Nrf2 pathway can contribute to neuronal survival and provide novel therapeutic potential for neuroinflammation-triggered neurodegeneration.

scholarly journals Differential Bacterial Survival, Replication, and Apoptosis-Inducing Ability of Salmonella Serovars within Human and Murine Macrophages

2000 ◽  
Vol 68 (3) ◽  
pp. 1005-1013 ◽  
Author(s):  
William R. Schwan ◽  
Xiao-Zhe Huang ◽  
Lan Hu ◽  
Dennis J. Kopecko
Keyword(s):  
Typhoid Fever ◽  
Systemic Infection ◽  
Peritoneal Macrophages ◽  
Human Macrophage ◽  
U937 Cells ◽  
Bacterial Survival ◽  
Human Macrophages ◽  
Macrophage Cells ◽  
Serovar Typhimurium ◽  
Murine Peritoneal Macrophages

ABSTRACT Salmonella serovars are associated with human diseases that range from mild gastroenteritis to host-disseminated enteric fever. Human infections by Salmonella enterica serovar Typhi can lead to typhoid fever, but this serovar does not typically cause disease in mice or other animals. In contrast, S. enterica serovar Typhimurium and S. entericaserovar Enteritidis, which are usually linked to localized gastroenteritis in humans and some animal species, elicit a systemic infection in mice. To better understand these observations, multiple strains of each of several chosen serovars of Salmonellawere tested for the ability in the nonopsonized state to enter, survive, and replicate within human macrophage cells (U937 and elutriated primary cells) compared with murine macrophage cells (J774A.1 and primary peritoneal cells); in addition, death of the infected macrophages was monitored. The serovar Typhimurium strains all demonstrated enhanced survival within J774A.1 cells and murine peritoneal macrophages, compared with the significant, almost 100-fold declines in viable counts noted for serovar Typhi strains. Viable counts for serovar Enteritidis either matched the level of serovar Typhi (J774A.1 macrophages) or were comparable to counts for serovar Typhimurium (murine peritoneal macrophages). Apoptosis was significantly higher in J774A.1 cells infected with serovar Typhimurium strain LT2 compared to serovar Typhi strain Ty2. On the other hand, serovar Typhi survived at a level up to 100-fold higher in elutriated human macrophages and 2- to 3-fold higher in U937 cells compared to the serovar Typhimurium and Enteritidis strains tested. Despite the differential multiplication of serovar Typhi during infection of U937 cells, serovar Typhi caused significantly less apoptosis than infections with serovar Typhimurium. These observations indicate variability in intramacrophage survival and host cytotoxicity among the various serovars and are the first to show differences in the apoptotic response of distinctSalmonella serovars residing in human macrophage cells. These studies suggest that nonopsonized serovar Typhimurium enters, multiplies within, and causes considerable, acute death of macrophages, leading to a highly virulent infection in mice (resulting in death within 14 days). In striking contrast, nonopsonized serovar Typhi survives silently and chronically within human macrophages, causing little cell death, which allows for intrahost dissemination and typhoid fever (low host mortality). The type of disease associated with any particular serovar of Salmonellais linked to the ability of that serovar both to persist within and to elicit damage in a specific host's macrophage cells.

Potential role of a series of lysine-/leucine-rich antimicrobial peptide in inhibiting lipopolysaccharide-induced inflammation

2018 ◽  
Vol 475 (22) ◽  
pp. 3687-3706 ◽  
Author(s):  
Weibing Dong ◽  
Xin Zhu ◽  
Xuan Zhou ◽  
Ying Yang ◽  
Xin Yan ◽  
...  
Keyword(s):  
Cell Membrane ◽  
Signaling Pathway ◽  
Inflammatory Responses ◽  
Antimicrobial Activities ◽  
Host Cells ◽  
Inflammatory Factors ◽  
Human Macrophage ◽  
U937 Cells ◽  
Wide Range ◽  
Anti Inflammatory

Antimicrobial peptides have broad-spectrum killing activities against bacteria, enveloped viruses, fungi and several parasites via cell membrane permeation and exhibit primarily immunomodulatory and anti-infective functions in their interactions with host cells. However, the mechanism underlying their anti-inflammatory activity remains to be elucidated. L-K6, an analog of temporin-1CEb isolated from the skin secretion of Rana chensinensis, has demonstrated a wide range of antimicrobial activities against gram-negative and gram-positive bacteria. In this study, the potent anti-inflammatory mechanism of L-K6 and its analogs in lipopolysaccharide (LPS)-stimulated human macrophage U937 cells were evaluated. We found that L-K6 suppressed the expression of inflammatory factors by two downstream signaling components in the MyD88-dependent pathway, including the mitogen-activated protein kinases (MAPKs) and the NF (nuclear factor)-κB signaling pathway, but its analog L-K5, which had the same amino acid sequence as L-K6 but no Lys residue at the –COOH terminal, only inhibited the phosphorylation of I-κB and NF-κB. Importantly, L-K6 and L-K5 were actively taken up by U937 cells through an independent cell membrane disruption mechanism and were eventually localized to the perinuclear region. The L-K6 uptake process was mediated by endocytosis, but L-K5 was specifically taken up by U937 cells via TLR4 endocytosis. Our results demonstrated that L-K6 can neutralize LPS and diassociate LPS micelles to inhibit LPS from triggering the proinflammatory signaling pathway, and by partially inhibiting inflammatory responses by the intracellular target. However, L-K5 may mainly inhibit proinflammatory responses by intracellular reporters to modulate the NF-κB signaling pathway.

scholarly journals Proinflammatory responses in SARS-CoV-2 infected and soluble spike glycoprotein S1 subunit activated human macrophages

2021 ◽  
Author(s):  
Kim Chiok ◽  
Kevin Hutchison ◽  
Lindsay Grace Miller ◽  
Santanu Bose ◽  
Tanya A Miura
Keyword(s):  
Virus Infection ◽  
Inflammatory Response ◽  
Virus Replication ◽  
Inflammatory Mediators ◽  
Inflammatory Responses ◽  
Activated Macrophages ◽  
Human Macrophages ◽  
Tnf Α ◽  
Proinflammatory Responses

Critically ill COVID-19 patients infected with SARS-CoV-2 display signs of generalized hyperinflammation. Macrophages trigger inflammation to eliminate pathogens and repair tissue, but this process can also lead to hyperinflammation and resulting exaggerated disease. The role of macrophages in dysregulated inflammation during SARS-CoV-2 infection is poorly understood. We used SARS-CoV-2 infected and glycosylated soluble SARS-CoV-2 Spike S1 subunit (S1) treated THP-1 human-derived macrophage-like cell line to clarify the role of macrophages in pro-inflammatory responses. Soluble S1 upregulated TNF-α and CXCL10 mRNAs, and induced secretion of TNF-α from THP-1 macrophages. While THP-1 macrophages did not support productive SARS-CoV-2 replication, virus infection resulted in upregulation of both TNF-α and CXCL10 genes. Our study shows that S1 is a key viral component inducing inflammatory response in macrophages, independently of virus replication. Thus, virus-infected or soluble S1-activated macrophages may become sources of pro-inflammatory mediators contributing to hyperinflammation in COVID-19 patients.

Sign in / Sign up

Export Citation Format

Share Document