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.
Th2 cytokines increase Staphylococcus aureus alpha toxin-induced keratinocyte death through the signal transducer and activator of transcription 6 (STAT6).
J. Invest. Dermatol.
PUBLISHED: 01-27-2014
Show Abstract
Hide Abstract
Atopic dermatitis (AD) is an inflammatory skin disease characterized by increased T-helper type 2 (Th2) cytokine expression. AD skin lesions are often exacerbated by Staphylococcus aureus-mediated secretion of the lytic virulence factor, alpha toxin. In the current study, we report that alpha toxin-induced cell death is greater in the skin from patients with AD compared with controls. Furthermore, we find that keratinocyte differentiation and Th2 cytokine exposure influence sensitivity to S. aureus alpha toxin-induced cell death. Differentiated keratinocytes are protected from cell death, whereas cells treated with Th2 cytokines have increased sensitivity to alpha toxin-induced lethality. Our data demonstrate that the downstream effects mediated by Th2 cytokines are dependent upon host expression of STAT6. We determine that Th2 cytokines induce biochemical changes that decrease levels of acid sphingomyelinase (SMase), an enzyme that cleaves sphingomyelin, an alpha toxin receptor. Furthermore, Th2 cytokines inhibit the production of lamellar bodies, organelles critical for epidermal barrier formation. Finally, we determine that SMase and its enzymatic product, phosphocholine, prevent Th2-mediated increases in alpha toxin-induced cell death. Therefore, our studies may help explain the increased propensity for Th2 cytokines to exacerbate S. aureus-induced skin disease, and provide a potential therapeutic target for treatment of AD.
Related JoVE Video
Related JoVE Video
The effects of airway microbiome on corticosteroid responsiveness in asthma.
Am. J. Respir. Crit. Care Med.
PUBLISHED: 09-13-2013
Show Abstract
Hide Abstract
The role of airway microbiome in corticosteroid response in asthma is unknown.
Related JoVE Video
Vitamin D enhances glucocorticoid action in human monocytes: involvement of granulocyte-macrophage colony-stimulating factor and mediator complex subunit 14.
J. Biol. Chem.
PUBLISHED: 04-09-2013
Show Abstract
Hide Abstract
Vitamin D (VitD) is now recognized for its pleiotrophic roles in regulating immune function. VitD interaction with other steroid receptor superfamily receptors in peripheral blood mononuclear cells is poorly understood. In the current study, we demonstrate that VitD enhanced glucocorticoid (GC) responses in human peripheral blood mononuclear cells because it stimulated GC induction of mitogen-activated protein kinase phosphatase-1 (MKP-1) and enhanced GC inhibition of LPS-induced IL-6. These VitD effects were abolished in purified CD14(+) and CD14(-) cells but were recovered in CD14(+) cells co-cultured with CD14(-) cells separated by tissue culture inserts. GM-CSF, found in culture supernatants from CD14(-) cells, was shown to mediate VitD enhancement of GC-induced MKP-1 production in monocytes via increased production of mediator complex subunit 14 (MED14). Recruitment of VitD receptor and MED14, 4.7 kbp upstream of the human MKP-1 gene transcription start site, enhanced binding of glucocorticoid receptor and histone H4 acetylation at the 4.6-kbp glucocorticoid response element of the MKP-1 promoter in the presence of GM-CSF in U937 cells. Knockdown of MED14 abolished VitD-mediated enhancement of GC-induced MKP-1 production. These data demonstrate VitD-mediated stimulation of GC anti-inflammatory effects in human monocytes and identify a role for GM-CSF and MED14 as mediators of this process.
Related JoVE Video
Inhibition of histone deacetylase 2 expression by elevated glucocorticoid receptor beta in steroid-resistant asthma.
Am. J. Respir. Crit. Care Med.
PUBLISHED: 06-10-2010
Show Abstract
Hide Abstract
Cross-talk between glucocorticoid receptors and histone deacetylases (HDACs) under steroid-insensitive conditions has not been explored.
Related JoVE Video
Decreased serum vitamin D levels in children with asthma are associated with increased corticosteroid use.
J. Allergy Clin. Immunol.
PUBLISHED: 02-08-2010
Show Abstract
Hide Abstract
There is little knowledge about clinical variables associated with vitamin D (VitD) insufficiency in asthmatic children.
Related JoVE Video
Vitamin D levels, lung function, and steroid response in adult asthma.
Am. J. Respir. Crit. Care Med.
PUBLISHED: 01-14-2010
Show Abstract
Hide Abstract
Patients with asthma exhibit variable response to inhaled corticosteroids (ICS). Vitamin D is hypothesized to exert effects on phenotype and glucocorticoid (GC) response in asthma.
Related JoVE Video
Estrogen inhibits glucocorticoid action via protein phosphatase 5 (PP5)-mediated glucocorticoid receptor dephosphorylation.
J. Biol. Chem.
PUBLISHED: 07-08-2009
Show Abstract
Hide Abstract
Although glucocorticoids suppress proliferation of many cell types and are used in the treatment of certain cancers, trials of glucocorticoid therapy in breast cancer have been a disappointment. Another suggestion that estrogens may affect glucocorticoid action is that the course of some inflammatory diseases tends to be more severe and less responsive to corticosteroid treatment in females. To date, the molecular mechanism of cross-talk between estrogens and glucocorticoids is poorly understood. Here we show that, in both MCF-7 and T47D breast cancer cells, estrogen inhibits glucocorticoid induction of the MKP-1 (mitogen-activated protein kinase phosphatase-1) and serum/glucocorticoid-regulated kinase genes. Estrogen did not affect glucocorticoid-induced glucocorticoid receptor (GR) nuclear translocation but reduced ligand-induced GR phosphorylation at Ser-211, which is associated with the active form of GR. We show that estrogen increases expression of protein phosphatase 5 (PP5), which mediates the dephosphorylation of GR at Ser-211. Gene knockdown of PP5 abolished the estrogen-mediated suppression of GR phosphorylation and induction of MKP-1 and serum/glucocorticoid-regulated kinase. More importantly, after PP5 knockdown estrogen-promoted cell proliferation was significantly suppressed by glucocorticoids. This study demonstrates cross-talk between estrogen-induced PP5 and GR action. It also reveals that PP5 inhibition may antagonize estrogen-promoted events in response to corticosteroid therapy.
Related JoVE Video
Identification of glucocorticoid-induced TNF receptor-related protein ligand on keratinocytes: ligation by GITR induces keratinocyte chemokine production and augments T-cell proliferation.
J. Invest. Dermatol.
PUBLISHED: 06-18-2009
Show Abstract
Hide Abstract
Glucocorticoid-induced tumor necrosis factor (TNF) receptor-related protein ligand (GITRL) is a recently described co-stimulatory molecule expressed by antigen-presenting cells (APCs). Activated keratinocytes are known to engage intraepithelial T cells through co-stimulatory molecules. This study investigated the expression and function of GITRL in resting keratinocytes. We showed by immunofluorescence and flow cytometry that keratinocytes from Balb/C and C57Bl/6 mice, as well as PAM 212 murine cell line keratinocytes and human epidermal keratinocytes (HEK), express cell-surface GITRL. Stimulation of murine skin biopsies and HEK with GITR fusion protein (GITR: Fc FP) resulted in mRNA induction for chemoattractants: cutaneous T-cell-attracting chemokine (CTACK), thymus and activation-regulated chemokine (TARC), IL-8, monocyte chemoattractant protein-1 (MCP-1), and murine beta-defensin 3 (MBD3). Immunofluorescent studies on mouse biopsies treated with GITR: Fc FP confirmed corresponding TARC and MCP-1 protein production by keratinocytes. Chemokine induction was shown to be NF-kappaB-mediated. T-cell proliferation was enhanced by the addition of keratinocytes. This was reversed by pretreatment with an anti-GITRL antibody. We conclude that keratinocytes express GITRL, and that through this important co-stimulatory molecule, they have the potential to influence T-cell numbers in the skin through chemokine production and through a direct cell-cell effect on T-cell proliferation.
Related JoVE Video
IFN-gamma reverses IL-2- and IL-4-mediated T-cell steroid resistance.
Am. J. Respir. Cell Mol. Biol.
PUBLISHED: 02-04-2009
Show Abstract
Hide Abstract
Corticosteroids are the most common therapeutic approach for control of tissue inflammation. Combination IL-2/IL-4 is known to induce T-cell steroid resistance. This can be reversed with IFN-gamma; however, the mechanism by which this occurs is unknown. In the current study, we found that treatment of peripheral blood mononuclear cells with combination IL-2/IL-4 for 48 hours, but not with IL-2 or IL-4 alone, abrogated dexamethasone (DEX)-induced glucocorticoid receptor (GCR)-alpha nuclear translocation in both CD4(+) and CD8(+) T cells. The presence of IL-4 significantly down-regulated IFN-gamma production by IL-2-stimulated cells. Importantly, addition of IFN-gamma to the IL-2/IL-4 combination restored GCRalpha nuclear translocation in response to DEX. Furthermore, DEX-induced mitogen-activated protein kinase (MAPK) phosphatase-1 induction, used as a readout for corticosteroid-induced transactivation, was significantly greater (P < 0.05) in media and IL-2/IL-4/IFN-gamma-treated conditions compared with IL-2/IL-4-treated cells. The combination of IL-2/IL-4 induced p38 MAPK activation in CD3(+) cells (30.5 +/- 5.7% cells expressed phospho-p38 MAPK versus no phospho-p38 MAPK expression after media treatment). The presence of the p38 MAPK inhibitor, SB203580, or IFN-gamma inhibited p38 MAPK phosphorylation and enhanced GCRalpha nuclear translocation in response to DEX. These data indicate that combination IL-2/IL-4 inhibits GCRalpha nuclear translocation in human T cells, and this effect is reversed by IFN-gamma via inhibition of p38 MAPK activation.
Related JoVE Video
Filaggrin-dependent secretion of sphingomyelinase protects against staphylococcal ?-toxin-induced keratinocyte death.
J. Allergy Clin. Immunol.
Show Abstract
Hide Abstract
The skin of patients with atopic dermatitis (AD) has defects in keratinocyte differentiation, particularly in expression of the epidermal barrier protein filaggrin. AD skin lesions are often exacerbated by Staphylococcus aureus-mediated secretion of the virulence factor ?-toxin. It is unknown whether lack of keratinocyte differentiation predisposes to enhanced lethality from staphylococcal toxins.
Related JoVE Video
Obesity impairs apoptotic cell clearance in asthma.
J. Allergy Clin. Immunol.
Show Abstract
Hide Abstract
Asthma in obese adults is typically more severe and less responsive to glucocorticoids than asthma in nonobese adults.
Related JoVE Video
Staphylococcus aureus ?-toxin modulates skin host response to viral infection.
J. Allergy Clin. Immunol.
Show Abstract
Hide Abstract
Patients with atopic dermatitis (AD) with a history of eczema herpeticum have increased staphylococcal colonization and infections. However, whether Staphylococcus aureus alters the outcome of skin viral infection has not been determined.
Related JoVE Video
Cluster analysis of obesity and asthma phenotypes.
PLoS ONE
Show Abstract
Hide Abstract
Asthma is a heterogeneous disease with variability among patients in characteristics such as lung function, symptoms and control, body weight, markers of inflammation, and responsiveness to glucocorticoids (GC). Cluster analysis of well-characterized cohorts can advance understanding of disease subgroups in asthma and point to unsuspected disease mechanisms. We utilized an hypothesis-free cluster analytical approach to define the contribution of obesity and related variables to asthma phenotype.
Related JoVE Video
Steroid requirements and immune associations with vitamin D are stronger in children than adults with asthma.
J. Allergy Clin. Immunol.
Show Abstract
Hide Abstract
The effects of serum vitamin D status on atopy, steroid requirement, and functional responsiveness to corticosteroids in children versus adults with asthma have not been studied systematically.
Related JoVE Video
Vitamin D inhibits monocyte/macrophage proinflammatory cytokine production by targeting MAPK phosphatase-1.
J. Immunol.
Show Abstract
Hide Abstract
It is estimated that 1 billion people around the world are vitamin D deficient. Vitamin D deficiency has been linked to various inflammatory diseases. However, the mechanism by which vitamin D reduces inflammation remains poorly understood. In this study, we investigated the inhibitory effects of physiologic levels of vitamin D on LPS-stimulated inflammatory response in human blood monocytes and explored potential mechanisms of vitamin D action. We observed that two forms of the vitamin D, 1,25(OH)(2)D(3), and 25(OH)D(3), dose dependently inhibited LPS-induced p38 phosphorylation at physiologic concentrations, IL-6 and TNF-? production by human monocytes. Upon vitamin D treatment, the expression of MAPK phosphatase-1 (MKP-1) was significantly upregulated in human monocytes and murine bone marrow-derived macrophages (BMM). Increased binding of the vitamin D receptor and increased histone H4 acetylation at the identified vitamin D response element of the murine and human MKP-1 promoters were demonstrated. Moreover, in BMM from MKP1(-/-) mice, the inhibition of LPS-induced p38 phosphorylation by vitamin D was completely abolished. Vitamin D inhibition of LPS-induced IL-6 and TNF-? production by BMM from MKP-1(-/-) mice was significantly reduced as compared with wild-type mice. In conclusion, this study identified the upregulation of MKP-1 by vitamin D as a novel pathway by which vitamin D inhibits LPS-induced p38 activation and cytokine production in monocytes/macrophages.
Related JoVE Video
Usefulness of PBMCs to predict clinical response to corticosteroids in asthmatic patients.
J. Allergy Clin. Immunol.
Show Abstract
Hide Abstract
Blood tests are needed to identify steroid-resistant (SR) asthmatic patients early so that they can be managed with alternative anti-inflammatory therapy.
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.