scholarly journals Kallikrein-related peptidase 6 exacerbates disease in an autoimmune model of multiple sclerosis

2016 ◽  
Vol 397 (12) ◽  
pp. 1277-1286 ◽  
Author(s):  
Hyesook Yoon ◽  
Isobel A. Scarisbrick
Keyword(s):  
Multiple Sclerosis ◽  
Spinal Cord ◽  
Inflammatory Cytokines ◽  
Immune Cells ◽  
Inflammatory Responses ◽  
Critical Role ◽  
Systemic Administration ◽  
Neurological Deficits ◽  
Interleukin 17 ◽  
The Impact

Abstract Kallikrein-related peptidase 6 (Klk6) is elevated in the serum of multiple sclerosis (MS) patients and is hypothesized to participate in inflammatory and neuropathogenic aspects of the disease. To test this hypothesis, we investigated the impact of systemic administration of recombinant Klk6 on the development and progression of MOG35-55-induced experimental autoimmune encephalomyelitis (EAE). First, we determined that Klk6 expression is elevated in the spinal cord of mice with EAE at the peak of clinical disease and in immune cells upon priming with the disease-initiating peptide in vitro. Systemic administration of recombinant Klk6 to mice during the priming phase of disease resulted in an exacerbation of clinical symptoms, including earlier onset of disease and higher levels of spinal cord inflammation and pathology. Treatment of MOG35-55-primed immune cells with Klk6 in culture enhanced expression of pro-inflammatory cytokines, interferon-γ, tumor necrosis factor, and interleukin-17, while reducing anti-inflammatory cytokines interleukin-4 and interleukin-5. Together these findings provide evidence that elevations in systemic Klk6 can bias the immune system towards pro-inflammatory responses capable of exacerbating the development of neuroinflammation and paralytic neurological deficits. We suggest that Klk6 represents an important target for conditions in which pro-inflammatory responses play a critical role in disease development, including MS.

scholarly journals The Role of Distinct Subsets of Macrophages in the Pathogenesis of MS and the Impact of Different Therapeutic Agents on These Populations

2021 ◽  
Vol 12 ◽  
Author(s):  
Maedeh Radandish ◽  
Parvin Khalilian ◽  
Nafiseh Esmaeil
Keyword(s):  
T Cells ◽  
Immune Cells ◽  
Inflammatory Responses ◽  
Critical Role ◽  
Myeloid Cell ◽  
Therapeutic Agents ◽  
Vital Role ◽  
Inflammatory Disorder ◽  
The Impact

Multiple sclerosis (MS) is a demyelinating inflammatory disorder of the central nervous system (CNS). Besides the vital role of T cells, other immune cells, including B cells, innate immune cells, and macrophages (MФs), also play a critical role in MS pathogenesis. Tissue-resident MФs in the brain’s parenchyma, known as microglia and monocyte-derived MФs, enter into the CNS following alterations in CNS homeostasis that induce inflammatory responses in MS. Although the neuroprotective and anti-inflammatory actions of monocyte-derived MФs and resident MФs are required to maintain CNS tolerance, they can release inflammatory cytokines and reactivate primed T cells during neuroinflammation. In the CNS of MS patients, elevated myeloid cells and activated MФs have been found and associated with demyelination and axonal loss. Thus, according to the role of MФs in neuroinflammation, they have attracted attention as a therapeutic target. Also, due to their different origin, location, and turnover, other strategies may require to target the various myeloid cell populations. Here we review the role of distinct subsets of MФs in the pathogenesis of MS and different therapeutic agents that target these cells.

scholarly journals Inflammatory Cytokines, Immune Cells, and Organ Interactions in Heart Failure

2021 ◽  
Vol 12 ◽  
Author(s):  
Huihui Li ◽  
Chen Chen ◽  
Dao Wen Wang
Keyword(s):  
Heart Failure ◽  
Clinical Trials ◽  
Inflammatory Cytokines ◽  
Immune Cells ◽  
Inflammatory Responses ◽  
Therapeutic Targets ◽  
Pathophysiological Mechanisms

Despite mounting evidence demonstrating the significance of inflammation in the pathophysiological mechanisms of heart failure (HF), most large clinical trials that target the inflammatory responses in HF yielded neutral or even worsening outcomes. Further in-depth understanding about the roles of inflammation in the pathogenesis of HF is eagerly needed. This review summarizes cytokines, cardiac infiltrating immune cells, and extracardiac organs that orchestrate the complex inflammatory responses in HF and highlights emerging therapeutic targets.

Abstract 19409: β2-Adrenergic Receptor Regulation of Innate Immune Responses Following Acute Myocardial Injury

Circulation ◽  
2015 ◽  
Vol 132 (suppl_3) ◽  
Author(s):  
Laurel A Grisanti ◽  
Anna Gumpert ◽  
Joshua Gorsky ◽  
Ashley A Repas ◽  
Erhe Gao ◽  
...  
Keyword(s):  
Immune Responses ◽  
Adrenergic Receptor ◽  
Inflammatory Responses ◽  
Critical Role ◽  
Cellular Migration ◽  
Chimeric Mouse ◽  
Ccr2 Expression ◽  
Β2 Adrenergic Receptor ◽  
The Impact

Inflammatory responses are important for cardiac remodeling and tissue repair after myocardial infarction (MI). The sympathetic nervous system is known to regulate immune responses, in large part through the β2-adrenergic receptor (β2AR), however the influence of β2AR in regulating the inflammatory response following MI is unknown. Thus, to examine the contribution of β2AR on immune cells following MI, wild-type (WT) mice were irradiated and then received β2ARKO or WT control bone marrow (BM) transplants to create immune cell-specific knockout (KO) animals. Lack of β2AR expression in BM resulted in 100% mortality from cardiac rupture within two weeks of receiving MI, in contrast to their WT counterparts that had ∼20% death. Granulocyte populations were sequestered in the spleen of β2ARKO chimeric mice resulting in reductions in post-MI infiltration of monocyte/macrophage, neutrophil and mast cell populations into the heart. Additionally, alterations in chemokine receptor levels, particularly CCR2, on BM resulted in decreased cellular migration, and use of a CCR2 antagonist in vivo recapitulated the β2ARKO chimeric mouse phenotype following MI. Administration of β2AR agonists in vitro and in vivo increased CCR2 expression and BM migration while β2AR antagonists decreased CCR2 expression and increased splenic leukocyte retention in vivo . Use of pepducins as allosteric modulators of β2AR signaling demonstrated the importance of β-arrestin-mediated signaling in increasing CCR2 expression and responses. The impact of β2AR deletion on BM cell CCR2 expression and migration, splenic retention of leukocytes and reciprocal cardiac leukocyte infiltration following MI could be reversed via lentivirus-mediated β2AR rescue in the β2ARKO BM prior to transplantation. These results demonstrate the critical role of β2AR in the regulation of CCR2 expression on hematopoietic cells and its importance in mounting an immune response to promote healing following acute cardiac injury.

scholarly journals Impact of Astrocyte Depletion upon Inflammation and Demyelination in a Murine Animal Model of Multiple Sclerosis

2019 ◽  
Vol 20 (16) ◽  
pp. 3922 ◽  
Author(s):  
Allnoch ◽  
Baumgärtner ◽  
Hansmann
Keyword(s):  
Multiple Sclerosis ◽  
Spinal Cord ◽  
Calcium Binding ◽  
Performance Test ◽  
Intraperitoneal Administration ◽  
Clinical Signs ◽  
Aquaporin 4 ◽  
Thoracic Spinal Cord ◽  
Thoracic Spinal ◽  
The Impact

Astrocytes play a key role in demyelinating diseases, like multiple sclerosis (MS), although many of their functions remain unknown. The aim of this study was to investigate the impact of astrocyte depletion upon de- and remyelination, inflammation, axonal damage, and virus distribution in Theiler`s murine encephalomyelitis (TME). Groups of two to six glial fibrillary acidic protein (GFAP)-thymidine-kinase transgenic SJL mice and SJL wildtype mice were infected with TME virus (TMEV) or mock (vehicle only). Astrocyte depletion was induced by the intraperitoneal administration of ganciclovir during the early and late phase of TME. The animals were clinically investigated while using a scoring system and a rotarod performance test. Necropsies were performed at 46 and 77 days post infection. Cervical and thoracic spinal cord segments were investigated using hematoxylin and eosin (H&E), luxol fast blue-cresyl violet (LFB), immunohistochemistry targeting Amigo2, aquaporin 4, CD3, CD34, GFAP, ionized calcium-binding adapter molecule 1 (Iba1), myelin basic protein (MBP), non-phosphorylated neurofilaments (np-NF), periaxin, S100A10, TMEV, and immunoelectron microscopy. The astrocyte depleted mice showed a deterioration of clinical signs, a downregulation and disorganization of aquaporin 4 in perivascular astrocytes accompanied by vascular leakage. Furthermore, astrocyte depleted mice showed reduced inflammation and lower numbers of TMEV positive cells in the spinal cord. The present study indicates that astrocyte depletion in virus triggered CNS diseases contributes to a deterioration of clinical signs that are mediated by a dysfunction of perivascular astrocytes.

Intrathecal baclofen for intractable spasticity of spinal origin: results of a long-term multicenter study

1993 ◽  
Vol 78 (2) ◽  
pp. 226-232 ◽  
Author(s):  
Robert J. Coffey ◽  
David Cahill ◽  
William Steers ◽  
T. S. Park ◽  
Joe Ordia ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Intrathecal Baclofen ◽  
Neurological Deficits ◽  
Pump System ◽  
Postoperative Score ◽  
Long Term Treatment ◽  
Cord Injury

✓ A total of 93 patients with intractable spasticity due to either spinal cord injury (59 cases), multiple sclerosis (31 cases), or other spinal pathology (three cases) were entered into a randomized double-blind placebocontrolled screening protocol of intrathecal baclofen test injections. Of the 88 patients who responded to an intrathecal bolus of 50, 75, or 100 µg of baclofen, 75 underwent implantation of a programmable pump system for chronic therapy. Patients were followed for 5 to 41 months after surgery (mean 19 months). No deaths or new permanent neurological deficits occurred as a result of surgery or chronic intrathecal baclofen administration. Rigidity was reduced from a mean preoperative Ashworth scale score of 3.9 to a mean postoperative score of 1.7. Muscle spasms were reduced from a mean preoperative score of 3.1 (on a fourpoint scale) to a mean postoperative score of 1.0. Although the dose of intrathecal baclofen required to control spasticity increased with time, drug tolerance was not a limiting factor in this study. Only one patient withdrew from the study because of a late surgical complication (pump pocket infection). Another patient received an intrathecal baclofen overdose because of a human error in programming the pump. The results of this study indicate that intrathecal baclofen infusion can be safe and effective for the long-term treatment of intractable spasticity in patients with spinal cord injury or multiple sclerosis.

scholarly journals The Surface-Associated Exopolysaccharide of Bifidobacterium longum 35624 Plays an Essential Role in Dampening Host Proinflammatory Responses and Repressing Local TH17 Responses

2016 ◽  
Vol 82 (24) ◽  
pp. 7185-7196 ◽  
Author(s):  
Elisa Schiavi ◽  
Marita Gleinser ◽  
Evelyn Molloy ◽  
David Groeger ◽  
Remo Frei ◽  
...  
Keyword(s):  
Immune Response ◽  
Immune Cells ◽  
Essential Role ◽  
Inflammatory Responses ◽  
Bifidobacterium Longum ◽  
Molecular Characteristics ◽  
Interleukin 17 ◽  
Content Type ◽  
Exopolysaccharide Production

ABSTRACTThe immune-modulating properties of certain bifidobacterial strains, such asBifidobacterium longumsubsp.longum35624 (B. longum35624), have been well described, although the strain-specific molecular characteristics associated with such immune-regulatory activity are not well defined. It has previously been demonstrated thatB. longum35624 produces a cell surface exopolysaccharide (sEPS), and in this study, we investigated the role played by this exopolysaccharide in influencing the host immune response.B. longum35624 induced relatively low levels of cytokine secretion from human dendritic cells, whereas an isogenic exopolysaccharide-negative mutant derivative (termed sEPSneg) induced vastly more cytokines, including interleukin-17 (IL-17), and this response was reversed when exopolysaccharide production was restored in sEPSnegby genetic complementation. Administration ofB. longum35624 to mice of the T cell transfer colitis model prevented disease symptoms, whereas sEPSnegdid not protect against the development of colitis, with associated enhanced recruitment of IL-17+lymphocytes to the gut. Moreover, intranasal administration of sEPSnegalso resulted in enhanced recruitment of IL-17+lymphocytes to the murine lung. These data demonstrate that the particular exopolysaccharide produced byB. longum35624 plays an essential role in dampening proinflammatory host responses to the strain and that loss of exopolysaccharide production results in the induction of local TH17 responses.IMPORTANCEParticular gut commensals, such asB. longum35624, are known to contribute positively to the development of mucosal immune cells, resulting in protection from inflammatory diseases. However, the molecular basis and mechanisms for these commensal-host interactions are poorly described. In this report, an exopolysaccharide was shown to be decisive in influencing the immune response to the bacterium. We generated an isogenic mutant unable to produce exopolysaccharide and observed that this mutation caused a dramatic change in the response of human immune cellsin vitro. In addition, the use of mouse models confirmed that lack of exopolysaccharide production induces inflammatory responses to the bacterium. These results implicate the surface-associated exopolysaccharide of theB. longum35624 cell envelope in the prevention of aberrant inflammatory responses.

scholarly journals Dooming Phagocyte Responses: Inflammatory Effects of Endogenous Oxidized Phospholipids

2021 ◽  
Vol 12 ◽  
Author(s):  
Marco Di Gioia ◽  
Ivan Zanoni
Keyword(s):  
Immune Cells ◽  
Molecular Mechanisms ◽  
Inflammatory Responses ◽  
Inflammatory Diseases ◽  
Biological Activities ◽  
Oxidized Lipids ◽  
Oxidized Phospholipids ◽  
Clinical Tools ◽  
Stress Mediators ◽  
The Impact

Endogenous oxidized phospholipids are produced during tissue stress and are responsible for sustaining inflammatory responses in immune as well as non-immune cells. Their local and systemic production and accumulation is associated with the etiology and progression of several inflammatory diseases, but the molecular mechanisms that underlie the biological activities of these oxidized phospholipids remain elusive. Increasing evidence highlights the ability of these stress mediators to modulate cellular metabolism and pro-inflammatory signaling in phagocytes, such as macrophages and dendritic cells, and to alter the activation and polarization of these cells. Because these immune cells serve a key role in maintaining tissue homeostasis and organ function, understanding how endogenous oxidized lipids reshape phagocyte biology and function is vital for designing clinical tools and interventions for preventing, slowing down, or resolving chronic inflammatory disorders that are driven by phagocyte dysfunction. Here, we discuss the metabolic and signaling processes elicited by endogenous oxidized lipids and outline new hypotheses and models to elucidate the impact of these lipids on phagocytes and inflammation.

scholarly journals Modulation of monocyte responses by progressive multiple sclerosis therapy.

2021 ◽  
Author(s):  
◽  
Carl Beyers
Keyword(s):  
Multiple Sclerosis ◽  
Inflammatory Cytokines ◽  
Immune Cell ◽  
Inflammatory Responses ◽  
Neurodegenerative Disorder ◽  
Cell Activity ◽  
Cell Subset ◽  
Disease Heterogeneity ◽  
Receptor Affinity ◽  
Anti Inflammatory

<p>Multiple sclerosis (MS) is an immune-mediated neurodegenerative disorder that is distinguished by neuroinflammation and demyelination. MS is severely debilitating and remains the most common cause of disability arising from non-traumatic brain and CNS damage in adults. In its progressive phase there are no effective treatments, so new therapy options are an urgent research priority. Extensive work has been done on the role of the adaptive immune system in contributing to the disease pathology and on the effects of therapies targeting lymphocytes in relapsing-remitting MS. Fewer studies have examined innate immune cells in people with progressive MS. This thesis addresses that gap by profiling monocyte phenotype and function in response to new and repurposed drugs that may provide benefit in progressive MS. This was achieved by modelling the drugs’ effects in vitro using peripheral blood cells from people with progressive MS and healthy subjects.   Clozapine is an atypical antipsychotic with broad receptor affinity that is primarily used to treat refractory schizophrenia. In addition to is antipsychotic action through dopamine receptor (DR) D2, its broad neuro-immune receptor affinity is thought to dampen inflammatory responses in the CNS. This thesis highlights clozapine’s anti-inflammatory effect by demonstrating a reduction in the expression of pro-inflammatory cytokines that are associated with MS pathology in treated monocytes. Clozapine also induced a significant increase in the expression of D1. We observed that D1 expression changes happened alongside alterations to immune cell activity and that MS participant monocytes were much more susceptible to DR expression changes compared to healthy people. Together this data substantiates clozapine as a potential treatment for progressive disease.   MIS416 is a large, non-soluble microparticle suspension that induces nuclear factor kappa B (NFB) dependent cytokine induction. We show here that monocytes are key cytokine responder cells to MIS416 and explore the molecular mechanism by demonstrating its effects on transcription factor activity. Our data showing increased production of cytokines by MIS416 suggests a route of treatment efficacy through tolerisation mechanisms, and by reducing inflammation through upregulation of anti-inflammatory cytokines and negative feedback from pro-inflammatory cytokine release. Furthermore, we demonstrate how disease heterogeneity, phenotype, and genotype could significantly affect drug response outcomes in patients who received the drug as part of a phase 2 clinical trial.   Much of this work was done using new spectral cytometer technology. Its use allowed for the novel approach that enabled the subtraction of autofluorescent noise from out data, and we demonstrate its efficient functioning, ease of use, and utility in acquiring high dimensional datasets. The resulting large dataset allowed us the opportunity to interrogate it using bioinformatics tools, and we show their utility as adjunct tools to conventional methods of gating and statistical analysis. These analyses help demonstrate that monocytes are a heterogenous immune cell subset that is functionally distinct in people with progressive MS when compared to monocytes from healthy individuals.</p>

Critical role of microglia in the inflammatory response after spinal injury

2015 ◽  
Vol 3 (3) ◽  
pp. 453-462
Author(s):  
Ya-Yun Shi
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Inflammatory Responses ◽  
Spinal Injury ◽  
Critical Role ◽  
Cell Types ◽  
Inflammatory Factors ◽  
Cytokines And Chemokines ◽  
Cord Injury

Spinal cord injury induces a robust neuroinflammatory response that includes marked changes in the variety of endogenous CNS cell types specially microglia. In response to spinal injury, microglia undergo dramatic changes in cell morphology and promote inflammatory responses, which result in production of inflammatory factors and oxidative stress including reactive oxygen species. Further pro-inflammatory cytokines and chemokines are also rapidly up-regulated and likely contribute to microglial activation. This topic review will explore the current research on microglial responses to spinal injury and the recent progress in the pharmacologic and molecular targeting of microglia in spinal injury. Finally, we explore the argument for a positive versus negative role of microglia after spinal cord injury.

scholarly journals Minocycline Has Anti-inflammatory Effects and Reduces Cytotoxicity in an Ex Vivo Spinal Cord Slice Culture Model of West Nile Virus Infection

2017 ◽  
Vol 91 (22) ◽  
Author(s):  
Eamon D. Quick ◽  
Scott Seitz ◽  
Penny Clarke ◽  
Kenneth L. Tyler
Keyword(s):  
Spinal Cord ◽  
West Nile Virus ◽  
Immune Cells ◽  
Microglial Activation ◽  
Macrophage Activation ◽  
Inflammatory Responses ◽  
Ex Vivo ◽  
West Nile ◽  
Expression Of Genes ◽  
Anti Inflammatory

ABSTRACT West Nile virus (WNV) is a neurotropic flavivirus that can cause significant neurological disease. Mouse models of WNV infection demonstrate that a proinflammatory environment is induced within the central nervous system (CNS) after WNV infection, leading to entry of activated peripheral immune cells. We utilized ex vivo spinal cord slice cultures (SCSC) to demonstrate that anti-inflammatory mechanisms may also play a role in WNV-induced pathology and/or recovery. Microglia are a type of macrophage that function as resident CNS immune cells. Similar to mouse models, infection of SCSC with WNV induces the upregulation of proinflammatory genes and proteins that are associated with microglial activation, including the microglial activation marker Iba1 and CC motif chemokines CCL2, CCL3, and CCL5. This suggests that microglia assume a proinflammatory phenotype in response to WNV infection similar to the proinflammatory (M1) activation that can be displayed by other macrophages. We now show that the WNV-induced expression of these and other proinflammatory genes was significantly decreased in the presence of minocycline, which has antineuroinflammatory properties, including the ability to inhibit proinflammatory microglial responses. Minocycline also caused a significant increase in the expression of anti-inflammatory genes associated with alternative anti-inflammatory (M2) macrophage activation, including interleukin 4 (IL-4), IL-13, and FIZZ1. Minocycline-dependent alterations to M1/M2 gene expression were associated with a significant increase in survival of neurons, microglia, and astrocytes in WNV-infected slices and markedly decreased levels of inducible nitric oxide synthase (iNOS). These results demonstrate that an anti-inflammatory environment induced by minocycline reduces viral cytotoxicity during WNV infection in ex vivo CNS tissue. IMPORTANCE West Nile virus (WNV) causes substantial morbidity and mortality, with no specific therapeutic treatments available. Antiviral inflammatory responses are a crucial component of WNV pathology, and understanding how they are regulated is important for tailoring effective treatments. Proinflammatory responses during WNV infection have been extensively studied, but anti-inflammatory responses (and their potential protective and reparative capabilities) following WNV infection have not been investigated. Minocycline induced the expression of genes associated with the anti-inflammatory (M2) activation of CNS macrophages (microglia) in WNV-infected SCSC while inhibiting the expression of genes associated with proinflammatory (M1) macrophage activation and was protective for multiple CNS cell types, indicating its potential use as a therapeutic reagent. This ex vivo culture system can uniquely address the ability of CNS parenchymal cells (neurons, astrocytes, and microglia) to respond to minocycline and to modulate the inflammatory environment and cytotoxicity in response to WNV infection without peripheral immune cell involvement.

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