scholarly journals N-Formylated Peptide Induces Increased Expression of Both Formyl Peptide Receptor 2 (Fpr2) and Toll-Like Receptor 9 (TLR9) in Schwannoma Cells—An In Vitro Model for Early Inflammatory Profiling of Schwann Cells

Cells ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 2661
Author(s):  
Andrea Korimová ◽  
Petr Dubový
Keyword(s):  
Schwann Cells ◽  
Chemokine Receptors ◽  
In Vitro Model ◽  
Formyl Peptide Receptor ◽  
Toll Like Receptor ◽  
Western Blots ◽  
Peptide Receptor ◽  
Formyl Peptide ◽  
Vitro Model

Following nerve injury, disintegrated axonal mitochondria distal to the injury site release mitochondrial formylated peptides and DNA that can induce activation and inflammatory profiling of Schwann cells via formyl peptide receptor 2 (Fpr2) and toll-like receptor 9 (TLR9), respectively. We studied RT4 schwannoma cells to investigate the regulation of Fpr2 and TLR9 after stimulation with fMLF as a prototypical formylated peptide. RT4 cells were treated with fMLF at various concentrations and times with and without pretreatment with inhibitors (chloroquine for activated TLR9, PBP10 for Fpr2). Western blots of Fpr2, TLR9, p-p38, p-NFκB, and IL-6 were compared in relation to inflammatory profiling of RT4 cells and chemokine receptors (CCR2, CXCR4) as potential co-receptors of Fpr2. fMLF stimulation upregulated Fpr2 in RT4 cells at low concentrations (10 nM and 100 nM) but higher concentrations were required (10 µM and 50 µM) when the cells were pretreated with an activated TLR9 inhibitor. Moreover, the higher concentrations of fMLF could modulate TLR9 and inflammatory markers. Upregulation of Fpr2 triggered by 10 nM and 100 nM fMLF coincided with higher levels of chemokine receptors (CCR2, CXCR4) and PKCβ. Treating RT4 cells with fMLF, as an in vitro model of Schwann cells, uncovered Schwann cells’ complex responses to molecular patterns of release from injured axonal mitochondria.

scholarly journals Development, characterisation and in vitro evaluation of lanthanide-based FPR2/ALX-targeted imaging probes

2019 ◽  
Vol 48 (44) ◽  
pp. 16764-16775 ◽  
Author(s):  
Tamara Boltersdorf ◽  
Junaid Ansari ◽  
Elena Y. Senchenkova ◽  
Lijun Jiang ◽  
Andrew J. P. White ◽  
...  
Keyword(s):  
Lanthanide Complexes ◽  
Formyl Peptide Receptor ◽  
Human Neutrophils ◽  
Targeted Imaging ◽  
In Vitro Evaluation ◽  
Peptide Receptor ◽  
Imaging Probes ◽  
Formyl Peptide

Formyl Peptide Receptor (FPR)-targeted lanthanide complexes with long-lived emission in stimulated human neutrophils.

scholarly journals Pre-clinical evaluation of advanced nerve guide conduits using a novel 3D in vitro testing model

2018 ◽  
Vol 4 (1) ◽  
Author(s):  
Mehri Behbehani ◽  
Adam Glen ◽  
Caroline S. Taylor ◽  
Alexander Schuhmacher ◽  
Frederik Claeyssens ◽  
...  
Keyword(s):  
Schwann Cells ◽  
In Vitro Model ◽  
Ex Vivo ◽  
Donor Site ◽  
Neuronal Cell ◽  
Donor Site Morbidity ◽  
Animal Testing ◽  
Physical Support ◽  
Vitro Model

Autografts are the current gold standard for large peripheral nerve defects in clinics despite the frequently occurring side effects like donor site morbidity. Hollow nerve guidance conduits (NGC) are proposed alternatives to autografts, but fail to bridge gaps exceeding 3 cm in humans. Internal NGC guidance cues like microfibres are believed to enhance hollow NGCs by giving additional physical support for directed regeneration of Schwann cells and axons. In this study, we report a new 3D in vitro model that allows the evaluation of different intraluminal fibre scaffolds inside a complete NGC. The performance of electrospun polycaprolactone (PCL) microfibres inside 5 mm long polyethylene glycol (PEG) conduits was investigated in neuronal cell and dorsal root ganglion (DRG) cultures in vitro. Z-stack confocal microscopy revealed the aligned orientation of neuronal cells along the fibres throughout the whole NGC length and depth. The number of living cells in the centre of the scaffold was not significantly different to the tissue culture plastic (TCP) control. For ex vivo analysis, DRGs were placed on top of fibre-filled NGCs to simulate the proximal nerve stump. In 21 days of culture, Schwann cells and axons infiltrated the conduits along the microfibres with 2.2 ± 0.37 mm and 2.1 ± 0.33 mm respectively. We conclude that this in vitro model can help define internal NGC scaffolds in the future by comparing different fibre materials, composites and dimensions in one setup prior to animal testing.

scholarly journals Detrimental Role of miRNA-144-3p in Intracerebral Hemorrhage Induced Secondary Brain Injury is Mediated by Formyl Peptide Receptor 2 Downregulation BothIn VivoandIn Vitro

2018 ◽  
Vol 28 (6) ◽  
pp. 723-738 ◽  
Author(s):  
Weijian Fan ◽  
Xiang Li ◽  
Dongping Zhang ◽  
Haiying Li ◽  
Haitao Shen ◽  
...  
Keyword(s):  
Brain Injury ◽  
Intracerebral Hemorrhage ◽  
Formyl Peptide Receptor ◽  
Akt Pathway ◽  
Secondary Brain Injury ◽  
Peptide Receptor ◽  
Formyl Peptide

Although microRNA-144-3p (miRNA-144-3p) has been shown to suppress tumor proliferation and invasion, its function in intracerebral hemorrhage (ICH)-induced secondary brain injury (SBI) remains unclear. Thus, this study was designed to investigate the role of miRNA-144-3p in ICH. To accomplish this, we used adult male Sprague-Dawley rats to establish an in vivo ICH model by injecting autologous blood, while cultured primary rat cortical neurons were exposed to oxyhemoglobin (OxyHb) to mimic ICH in vitro. To examine the role of miRNA-144-3p in ICH-induced SBI, we used an miRNA-144-3p mimic and inhibitor both in vivo and in vitro. Following ICH induction, we found miRNA-144-3p expression to increase. Additionally, we predicted the formyl peptide receptor 2 (FPR2) to be a potential miRNA-144-3p target, which we validated experimentally, with FPR2 expression downregulated when miRNA-144-3p was upregulated. Furthermore, elevated miRNA-144-3p levels aggravated brain edema and neurobehavioral disorders and induced neuronal apoptosis via the downregulation of FPR2 both in vivo and in vitro. We suspected that these beneficial effects provided by FPR2 were associated with the PI3K/AKT pathway. We validated this finding by overexpressing FPR2 while inhibiting PI3K/AKT in vitro and in vivo. In conclusion, miRNA-144-3p aggravated ICH-induced SBI by targeting and downregulating FPR2, thereby contributing to neurological dysfunction and neural apoptosis via PI3K/AKT pathway activation. These findings suggest that inhibiting miRNA-144-3p may offer an effective approach to attenuating brain damage incurred after ICH and a potential therapy to improve ICH-induced SBI.

The synthetic peptide WKYMVm attenuates the function of the chemokine receptors CCR5 and CXCR4 through activation of formyl peptide receptor-like 1

Blood ◽  
2001 ◽  
Vol 97 (10) ◽  
pp. 2941-2947 ◽  
Author(s):  
Bao-Qun Li ◽  
Michele A. Wetzel ◽  
Judy A. Mikovits ◽  
Earl E. Henderson ◽  
Thomas J. Rogers ◽  
...  
Keyword(s):  
Cell Lines ◽  
Envelope Glycoprotein ◽  
Synthetic Peptide ◽  
Chemokine Receptors ◽  
Significant Inhibition ◽  
Formyl Peptide Receptor ◽  
Peptide Receptor ◽  
Formyl Peptide ◽  
Heterologous Desensitization ◽  
Hiv 1

Abstract The G protein–coupled 7 transmembrane (STM) chemoattractant receptors can be inactivated by heterologous desensitization. Earlier work showed that formly peptide receptor-like 1 (FPRL1), an STM receptor with low affinity for the bacterial chemotactic peptide formyl-methionyl-leucyl-phenylalamine (fMLF), is activated by peptide domains derived from the human immunodeficiency virus (HIV)-1 envelope glycoprotein gp120 and its activation results in desensitization and down-regulation of the chemokine receptors CCR5 and CXCR4 from monocyte surfaces. This study investigated the possibility of interfering with the function of CCR5 or CXCR4 as HIV-1 coreceptors by activating FPRL1. Cell lines were established expressing FPRL1 in combination with CD4/CXCR4 or CD4/CCR5 and the effect of a synthetic peptide, WKYMVm, a potent activator of formyl peptide receptors with preference for FPRL1 was determined. Both CXCR4 and CCR5 were desensitized by activation of the cells with WKYMVm via a staurosporine-sensitive pathway. This desensitization of CXCR4 and CCR5 also attenuated their capacity as the fusion cofactors for HIV-1 envelope glycoprotein and resulted in a significant inhibition of p24 production by cell lines infected with HIV-1 that use CCR5 or CXCR4 as coreceptors. Furthermore, WKYMVm inhibited the infection of human peripheral monocyte–derived macrophages and CD4+ T lymphocytes by R5 or X4 strains of HIV-1, respectively. These results indicate that heterologous desensitization of CCR5 and CXCR4 by an FPRL1 agonist attenuates their major biologic functions and suggest an approach to the development of additional anti-HIV-1 agents.

scholarly journals Exocytosis of Neutrophil Formyl Peptide Receptor-Like 1 (fPRL1) Results in Downregulation of Cytoplasmic fPRL1 in Patients with Purulent Dermatitis

2007 ◽  
Vol 14 (6) ◽  
pp. 678-684
Author(s):  
Eiji Ohara ◽  
Yoshitaka Kumon ◽  
Toshihiro Kobayashi ◽  
Hiroaki Takeuchi ◽  
Tetsuro Sugiura
Keyword(s):  
Formyl Peptide Receptor ◽  
Morphological Alteration ◽  
Cellular Membranes ◽  
Distinctive Features ◽  
Peptide Receptor ◽  
Formyl Peptide ◽  
Activated Neutrophils ◽  
Blood Neutrophils

ABSTRACT N-Formyl peptide receptor-like 1 (fPRL1) is a member of the chemoattractant subfamily of G protein-coupled receptors and plays a key role in inflammation via chemotaxis and the regulation of mediator release from leukocytes. Activated fPRL1 has recently been shown to induce a complicated pattern of cellular signaling in vitro, but the details of the regulation and alteration of leukocyte cellular fPRL1 during inflammation in vivo remain unclear. To clarify the alteration of neutrophil fPRL1 during inflammation in vivo, the immunohistochemical staining of neutrophil fPRL1 in samples from patients with purulent dermatitis was performed. The in vitro morphological alteration of neutrophil fPRL1 on cellular membranes by stimulation with N-formylmethionyl-leucyl-phenylalanine (fMLP) was also examined. Both the cytoplasm and the cellular membranes of blood neutrophils stained strongly for fPRL1. On the other hand, the cellular membranes of neutrophils in dermatitis tissue stained strongly for fPRL1 but the cytoplasm stained weakly. The enhancement of neutrophil fPRL1 on cellular membranes by stimulation with fMLP indicates the exocytosis of neutrophil fPRL1-containing granules. In conclusion, we for the first time confirmed the alteration of neutrophil fPRL1 in clinical cases of purulent dermatitis. Cytoplasm that was weakly stained and cellular membranes that were well stained for fPRL1 were considered to be distinctive features of activated neutrophils in purulent dermatitis tissue.

scholarly journals Serum amyloid A1 isoforms display different efficacy at Toll-like receptor 2 and formyl peptide receptor 2

Immunobiology ◽  
2014 ◽  
Vol 219 (12) ◽  
pp. 916-923 ◽  
Author(s):  
Mingjie Chen ◽  
Huibing Zhou ◽  
Ni Cheng ◽  
Feng Qian ◽  
Richard D. Ye
Keyword(s):  
Serum Amyloid ◽  
Formyl Peptide Receptor ◽  
Toll Like Receptor ◽  
Peptide Receptor ◽  
Formyl Peptide ◽  
Toll Like Receptor 2 ◽  
Serum Amyloid A1

scholarly journals Diminished HIV Infection of Target CD4+ T Cells in a Toll-Like Receptor 4 Stimulated in vitro Model

2019 ◽  
Vol 10 ◽  
Author(s):  
Ross Cromarty ◽  
Alex Sigal ◽  
Lenine J. P. Liebenberg ◽  
Lyle R. McKinnon ◽  
Salim S. Abdool Karim ◽  
...  
Keyword(s):  
T Cells ◽  
Hiv Infection ◽  
Cd4 T Cells ◽  
In Vitro Model ◽  
Toll Like Receptor ◽  
Toll Like Receptor 4 ◽  
Vitro Model
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