JoVE Visualize What is visualize?
Stop Reading. Start Watching.
Advanced Search
Stop Reading. Start Watching.
Regular Search
Find video protocols related to scientific articles indexed in Pubmed.
IL-32 Promotes Angiogenesis.
J. Immunol.
PUBLISHED: 12-11-2013
Show Abstract
Hide Abstract
IL-32 is a multifaceted cytokine with a role in infections, autoimmune diseases, and cancer, and it exerts diverse functions, including aggravation of inflammation and inhibition of virus propagation. We previously identified IL-32 as a critical regulator of endothelial cell (EC) functions, and we now reveal that IL-32 also possesses angiogenic properties. The hyperproliferative ECs of human pulmonary arterial hypertension and glioblastoma multiforme exhibited a markedly increased abundance of IL-32, and, significantly, the cytokine colocalized with integrin ?V?3. Vascular endothelial growth factor (VEGF) receptor blockade, which resulted in EC hyperproliferation, increased IL-32 three-fold. Small interfering RNA-mediated silencing of IL-32 negated the 58% proliferation of ECs that occurred within 24 h in scrambled-transfected controls. Reduction of IL-32 neither affected apoptosis (insignificant changes in Bak-1, Bcl-2, Bcl-xL, lactate dehydrogenase, annexin V, and propidium iodide) nor VEGF or TGF-? levels, but siIL-32-transfected adult and neonatal ECs produced up to 61% less NO, IL-8, and matrix metalloproteinase-9, and up to 3-fold more activin A and endostatin. In coculture-based angiogenesis assays, IL-32? dose-dependently increased tube formation up to 3-fold; an ?V?3 inhibitor prevented this activity and reduced IL-32?-induced IL-8 by 85%. In matrigel plugs loaded with IL-32?, VEGF, or vehicle and injected into live mice, we observed the anticipated VEGF-induced increase in neocapillarization (8-fold versus vehicle), but unexpectedly, IL-32? was equally angiogenic. A second signal such as IFN-? was required to render cells responsive to exogenous IL-32?; importantly, this was confirmed using a completely synthetic preparation of IL-32?. In summary, we add angiogenic properties that are mediated by integrin ?V?3 but VEGF-independent to the portfolio of IL-32, implicating a role for this versatile cytokine in pulmonary arterial hypertension and neoplastic diseases.
Related JoVE Video
Act1 mediates IL-17-induced EAE pathogenesis selectively in NG2+ glial cells.
Nat. Neurosci.
PUBLISHED: 07-10-2013
Show Abstract
Hide Abstract
Interleukin 17 (IL-17) is a signature cytokine of Th17 cells. We previously reported that deletion of NF-?B activator 1 (Act1), the key transducer of IL-17 receptor signaling, from the neuroectodermal lineage in mice (neurons, oligodendrocytes and astrocytes) results in attenuated severity of experimental autoimmune encephalomyelitis (EAE). Here we examined the cellular basis of this observation. EAE disease course was unaffected by deletion of Act1 in neurons or mature oligodendrocytes, and Act1 deletion in astrocytes only modestly affected disease course. Deletion of Act1 in NG2(+) glia resulted in markedly reduced EAE severity. Furthermore, IL-17 induced characteristic inflammatory mediator expression in NG2(+) glial cells. IL-17 also exhibited strong inhibitory effects on the maturation of oligodendrocyte lineage cells in vitro and reduced their survival. These data identify NG2(+) glia as the major CNS cellular target of IL-17 in EAE. The sensitivity of oligodendrocyte lineage cells to IL-17-mediated toxicity further suggests a direct link between inflammation and neurodegeneration in multiple sclerosis.
Related JoVE Video
IRAK-M mediates Toll-like receptor/IL-1R-induced NF?B activation and cytokine production.
EMBO J.
PUBLISHED: 02-01-2013
Show Abstract
Hide Abstract
Toll-like receptors transduce their signals through the adaptor molecule MyD88 and members of the IL-1R-associated kinase family (IRAK-1, 2, M and 4). IRAK-1 and IRAK-2, known to form Myddosomes with MyD88-IRAK-4, mediate TLR7-induced TAK1-dependent NF?B activation. IRAK-M was previously known to function as a negative regulator that prevents the dissociation of IRAKs from MyD88, thereby inhibiting downstream signalling. However, we now found that IRAK-M was also able to interact with MyD88-IRAK-4 to form IRAK-M Myddosome to mediate TLR7-induced MEKK3-dependent second wave NF?B activation, which is uncoupled from post-transcriptional regulation. As a result, the IRAK-M-dependent pathway only induced expression of genes that are not regulated at the post-transcriptional levels (including inhibitory molecules SOCS1, SHIP1, A20 and I?B?), exerting an overall inhibitory effect on inflammatory response. On the other hand, through interaction with IRAK-2, IRAK-M inhibited TLR7-mediated production of cytokines and chemokines at translational levels. Taken together, IRAK-M mediates TLR7-induced MEKK3-dependent second wave NF?B activation to produce inhibitory molecules as a negative feedback for the pathway, while exerting inhibitory effect on translational control of cytokines and chemokines.
Related JoVE Video
Protection from RNA and DNA viruses by IL-32.
J. Immunol.
PUBLISHED: 02-23-2011
Show Abstract
Hide Abstract
Several studies have documented a proinflammatory role for IL-32, which induces IL-1?, IL-1?, IL-6, TNF, and chemokines via NF-?B, p38MAPK, and AP-1. However, IL-32 also participates in the responses to infection with viruses such as HIV-1 and influenza. In this study, we explored these antiviral properties of IL-32. Vital staining assays demonstrated that low concentrations (5-10 ng/ml) of rIL-32? protected epithelial WISH cells from vesicular stomatitis virus-induced cell death. By lactate dehydrogenase assays, treatment with IL-32? resulted in a 3- to 4-fold decrease in viral load. Specific silencing of IL-32 revealed that the antiviral responses triggered by the synthetic analogs of ssRNA viruses (polyuridine) and dsRNA viruses (polyinosinic-polycytidylic acid) were significantly weaker (2- to 3-fold more virus) in WISH cells in the absence of IL-32. Importantly, we discovered that the polyinosinic-polycytidylic acid-induced increase in production of IFN-? in human PBMC was nearly completely abolished when IL-32 was silenced. Moreover, we observed that IL-32 antagonizes the DNA virus HSV-2 in epithelial Vero cells as well as in human umbilical cord endothelial cells, as production of HSV-2 increased 8-fold upon silencing of IL-32 (p < 0.001). Mechanistically, we found that IL-32 used the PKR-eIF-2? as well as the MxA antiviral pathways. Unexpectedly, a considerable part of the antiviral properties of IL-32 was not dependent on IFNs; specific blockade of IFN activity reduced the antiviral properties of IL-32 only moderately. In conclusion, these data suggest a central role for IL-32 in the immune response to RNA and DNA viruses, which may be exploitable for clinical use in the future.
Related JoVE Video
IL-17 receptor signaling and T helper 17-mediated autoimmune demyelinating disease.
Trends Immunol.
PUBLISHED: 01-18-2011
Show Abstract
Hide Abstract
Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system (CNS). Experimental autoimmune encephalomyelitis (EAE) is widely used to dissect molecular mechanisms of MS and to develop new therapeutic strategies. The T helper 17 (Th17) subset of CD4 T cells plays a crucial role in the development of EAE. IL-17, a cytokine produced by Th17 cells, participates in EAE pathogenesis through induction of inflammatory gene expression in target cells. Recent work has shown that Act1, a U-box E3 ubiquitin ligase, is recruited to IL-17 receptor (IL-17R) upon IL-17 stimulation and is required for IL-17-mediated signaling. Here, we review the molecular and cellular mechanisms by which IL-17 and Act1-mediated signaling contribute to EAE.
Related JoVE Video
SIGIRR, a negative regulator of colon tumorigenesis.
Drug Discov Today Dis Mech
PUBLISHED: 01-01-2011
Show Abstract
Hide Abstract
Inappropriate activation of the Toll-IL-1R (TL-IL-1) signaling by commensal bacteria contributes to the pathogenesis of inflammatory bowel diseases and colitis-associated cancer. Recent studies have identified SIGIRR as a negative regulator of TL-IL-1 signaling. It dampens intestinal inflammation and tumorigenesis in the colon. In this review, we will discuss the role of SIGIRR in different cell types and the mechanisms underlying its tumor suppressor function.
Related JoVE Video
IL-37 is a fundamental inhibitor of innate immunity.
Nat. Immunol.
PUBLISHED: 07-12-2010
Show Abstract
Hide Abstract
The function of interleukin 37 (IL-37; formerly IL-1 family member 7) has remained elusive. Expression of IL-37 in macrophages or epithelial cells almost completely suppressed production of pro-inflammatory cytokines, whereas the abundance of these cytokines increased with silencing of endogenous IL-37 in human blood cells. Anti-inflammatory cytokines were unaffected. Mice with transgenic expression of IL-37 were protected from lipopolysaccharide-induced shock, and showed markedly improved lung and kidney function and reduced liver damage after treatment with lipopolysaccharide. Transgenic mice had lower concentrations of circulating and tissue cytokines (72-95% less) than wild-type mice and showed less dendritic cell activation. IL-37 interacted intracellularly with Smad3 and IL-37-expressing cells and transgenic mice showed less cytokine suppression when endogenous Smad3 was depleted. IL-37 thus emerges as a natural suppressor of innate inflammatory and immune responses.
Related JoVE Video
Increased cytokine production in interleukin-18 receptor alpha-deficient cells is associated with dysregulation of suppressors of cytokine signaling.
J. Biol. Chem.
PUBLISHED: 07-10-2009
Show Abstract
Hide Abstract
Since interleukin (IL)-18 is a proinflammatory cytokine, mice lacking IL-18 or its ligand-binding receptor (IL-18R) should exhibit decreased cytokine and chemokine production. Indeed, production of IL-1alpha, IL-6, and MIP-1alpha was reduced in IL-18 knock-out (ko) mouse embryonic fibroblast (MEF)-like cells. Unexpectedly, we observed a paradoxical 10-fold increase in IL-1beta-induced IL-6 production in MEF cells from mice deficient in the IL-18R alpha-chain (IL-18Ralpha) compared with wild type MEF. Similar increases were observed for IL-1alpha, MIP-1alpha, and prostaglandin E2. Likewise, coincubation with a specific IL-18Ralpha-blocking antibody augmented IL-1beta-induced cytokines in wild type and IL-18 ko MEF. Stable lines of IL-18Ralpha-depleted human A549 cells were generated using shRNA, resulting in an increase of IL-1beta-induced IL-1alpha, IL-6, and IL-8 compared to scrambled small hairpin RNA. In addition, we silenced IL-18Ralpha with small interfering RNA in primary human blood cells and observed up to 4-fold increases in the secretion of lipopolysaccharide- and IL-12/IL-18-induced IL-1beta, IL-6, interferon-gamma, and CD40L. Mechanistically, despite increases in Stat1 and IL-6, induction of SOCS1 and -3 (suppressor of cytokine signaling 1 and 3) was markedly reduced in the absence of IL-18Ralpha. Consistent with these observations, activation of the p38alpha/beta and ERK1/2 MAPKs and of protein kinase B/Akt increased in IL-18Ralpha ko MEF, whereas the negative feedback kinase MSK2 was more active in IL-18 ko cells. These data reveal a role for SOCS1 and -3 in the seemingly paradoxical hyperresponsive state in cells deficient in IL-18Ralpha, supporting the concept that IL-18Ralpha participates in both pro- and anti-inflammatory responses and that an endogenous ligand engages IL-18Ralpha to deliver an inhibitory signal.
Related JoVE Video
IL-32-dependent effects of IL-1beta on endothelial cell functions.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 02-19-2009
Show Abstract
Hide Abstract
Increasing evidence demonstrates that interleukin (IL)-32 is a pro-inflammatory cytokine, inducing IL-1alpha, IL-1beta, IL-6, tumor necrosis factor (TNF)-alpha, and chemokines via nuclear factor (NF)-kappaB, p38 mitogen-activated protein kinase (MAPK), and activating protein (AP)-1 activation. Here we report that IL-32 is expressed and is also functional in human vascular endothelial cells (EC) of various origins. Compared with primary blood monocytes, high levels of IL-32 are constitutively produced in human umbilical vein EC (HUVEC), aortic macrovascular EC, and cardiac as well as pulmonary microvascular EC. At concentrations as low as 0.1 ng/ml, IL-1beta stimulated IL-32 up to 15-fold over constitutive levels, whereas 10 ng/ml of TNFalpha or 100 ng/ml of lipopolysaccharide (LPS) were required to induce similar quantities of IL-32. IL-1beta-induced IL-32 was reduced by inhibition of the IkappaB kinase-beta/NF-kappaB and ERK pathways. In addition to IL-1beta, pro-coagulant concentrations of thrombin or fresh platelets increased IL-32 protein up to 6-fold. IL-1beta and thrombin induced an isoform-switch in steady-state mRNA levels from IL-32alpha/gamma to beta/epsilon. Adult EC responded in a similar fashion. To prove functionality, we silenced endogenous IL-32 with siRNA, decreasing intracellular IL-32 protein levels by 86%. The knockdown of IL-32 resulted in reduction of constitutive as well as IL-1beta-induced intercellular adhesion molecule-1 (ICAM-1) (of 55% and 54%, respectively), IL-1alpha (of 62% and 43%), IL-6 (of 53% and 43%), and IL-8 (of 46% and 42%). In contrast, the anti-inflammatory/anti-coagulant CD141/thrombomodulin increased markedly when IL-32 was silenced. This study introduces IL-32 as a critical regulator of endothelial function, expanding the properties of this cytokine relevant to coagulation, endothelial inflammation, and atherosclerosis.
Related JoVE Video
The psoriasis-associated D10N variant of the adaptor Act1 with impaired regulation by the molecular chaperone hsp90.
Nat. Immunol.
Show Abstract
Hide Abstract
Act1 is an essential adaptor in interleukin 17 (IL-17)-mediated signaling and is recruited to the receptor for IL-17 after stimulation with IL-17. Here we found that Act1 was a client protein of the molecular chaperone hsp90. The D10N variant of Act1 (Act1(D10N)) that is linked to susceptibility to psoriasis was defective in its interaction with hsp90, which resulted in a global loss of Act1 function. Act1-deficient mice modeled the mechanistic link between loss of Act1 function and susceptibility to psoriasis. Although Act1 was necessary for IL-17-mediated inflammation, Act1-deficient mice had a hyperactive response of the T(H)17 subset of helper T cells and developed spontaneous IL-22-dependent skin inflammation. In the absence of IL-17 signaling, IL-22 was the main contributor to skin inflammation, which provides a molecular mechanism for the association of Act1(D10N) with psoriasis susceptibility.
Related JoVE Video
Cutting edge: TNF receptor-associated factor 4 restricts IL-17-mediated pathology and signaling processes.
J. Immunol.
Show Abstract
Hide Abstract
The effector T cell subset, Th17, plays a significant role in the pathogenesis of multiple sclerosis and of other autoimmune diseases. The signature cytokine, IL-17, engages the IL-17R and recruits the E3-ligase NF-?B activator 1 (Act1) upon stimulation. In this study, we examined the role of TNFR-associated factor (TRAF)4 in IL-17 signaling and Th17-mediated autoimmune encephalomyelitis. Primary cells from TRAF4-deficient mice displayed markedly enhanced IL-17-activated signaling pathways and induction of chemokine mRNA. Adoptive transfer of MOG35-55 specific wild-type Th17 cells into TRAF4-deficient recipient mice induced an earlier onset of disease. Mechanistically, we found that TRAF4 and TRAF6 used the same TRAF binding sites on Act1, allowing the competition of TRAF4 with TRAF6 for the interaction with Act1. Taken together, the results of this study reveal the necessity of a unique role of TRAF4 in restricting the effects of IL-17 signaling and Th17-mediated disease.
Related JoVE Video

What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.