scholarly journals UBAC1/KPC2 Regulates TLR3 Signaling in Human Keratinocytes through Functional Interaction with the CARD14/CARMA2sh-TANK Complex

2020 ◽  
Vol 21 (24) ◽  
pp. 9365
Author(s):  
Pellegrino Mazzone ◽  
Michele Congestrì ◽  
Ivan Scudiero ◽  
Immacolata Polvere ◽  
Serena Voccola ◽  
...  

CARD14/CARMA2 is a scaffold molecule whose genetic alterations are linked to human inherited inflammatory skin disorders. However, the mechanisms through which CARD14/CARMA2 controls innate immune response and chronic inflammation are not well understood. By means of a yeast two-hybrid screening, we identified the UBA Domain Containing 1 (UBAC1), the non-catalytic subunit of the E3 ubiquitin-protein ligase KPC complex, as an interactor of CARMA2sh, the CARD14/CARMA2 isoform mainly expressed in human keratinocytes. UBAC1 participates in the CARMA2sh/TANK complex and promotes K63-linked ubiquitination of TANK. In human keratinocytes, UBAC1 negatively regulates the NF-κF-activating capacity of CARMA2sh following exposure to poly (I:C), an agonist of Toll-like Receptor 3. Overall, our data indicate that UBAC1 participates in the inflammatory signal transduction pathways involving CARMA2sh.

2021 ◽  
Vol 67 (4) ◽  
pp. 331-337
Author(s):  
M.I. Airapetov ◽  
S.O. Eresko ◽  
A.K. Vasilev ◽  
V.Y. Vasileva ◽  
E.R. Bychkov ◽  
...  

The pathogenetic mechanisms associated with alcohol use include dysregulation of the innate immune system mechanisms in the brain. TLR3 expression is increased in the postmortem material of the prefrontal cortex of humans. An increase in the TLR3 signaling activity leads to the induction of interferons (IFN). IFN are associated with depressive symptoms and, therefore, may play a role in the pathogenesis of alcoholism; however, the exact mechanisms of intracellular signaling mediated by the influence of ethanol are not fully elucidated and their study was the purpose of this work. The experimental results showed that ethanol and the TLR3 agonist Poly (I:C) increased the content of TLR3, IFNβ, and IFNγ mRNA in the prefrontal cortex. In addition, expression of the TRAIL encoding gene also increased, and this increase positively correlaed with the mRNA content of TLR3, IFNβ and IFNγ both under alcoholization conditions and after injections of the TLR3 agonist. The data obtained may indicate that alcoholization is able to activate TLR3-TRAIL-IFN-signaling in the prefrontal cortex of the brain.


Cells ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 1910
Author(s):  
Hellen S. Teixeira ◽  
Jiawei Zhao ◽  
Ethan Kazmierski ◽  
Denis F. Kinane ◽  
Manjunatha R. Benakanakere

The role of the adaptor molecule MyD88 is thought to be independent of Toll-like receptor 3 (TLR3) signaling. In this report, we demonstrate a previously unknown role of MyD88 in TLR3 signaling in inducing endogenous ligands of TLR2 to elicit innate immune responses. Of the various TLR ligands examined, the TLR3-specific ligand polyinosinic:polycytidylic acid (poly I:C), significantly induced TNF production and the upregulation of other TLR transcripts, in particular, TLR2. Accordingly, TLR3 stimulation also led to a significant upregulation of endogenous TLR2 ligands mainly, HMGB1 and Hsp60. By contrast, the silencing of TLR3 significantly downregulated MyD88 and TLR2 gene expression and pro-inflammatory IL1β, TNF, and IL8 secretion. The silencing of MyD88 similarly led to the downregulation of TLR2, IL1β, TNF and IL8, thus suggesting MyD88 to somehow act downstream of TLR3. Corroborating in vitro data, Myd88−/− knockout mice downregulated TNF, CXCL1; and phospho-p65 and phospho-IRF3 nuclear localization, upon poly I:C treatment in a mouse model of skin infection. Taken together, we identified a previously unknown role for MyD88 in the TLR3 signaling pathway, underlying the importance of TLRs and adapter protein interplay in modulating endogenous TLR ligands culminating in pro-inflammatory cytokine regulation.


Author(s):  
Tatsuro Saruga ◽  
Tadaatsu Imaizumi ◽  
Shogo Kawaguchi ◽  
Kazuhiko Seya ◽  
Tomoh Matsumiya ◽  
...  

AbstractC-X-C motif chemokine 10 (CXCL10) is an inflammatory chemokine and a key molecule in the pathogenesis of rheumatoid arthritis (RA). Melanoma differentiation-associated gene 5 (MDA5) is an RNA helicase that plays a role in innate immune and inflammatory reactions. The details of the regulatory mechanisms of CXCL10 production and the precise role of MDA5 in RA synovitis have not been fully elucidated. The aim of this study was to examine the role of MDA5 in regulating CXCL10 expression in cultured human rheumatoid fibroblast-like synoviocytes (RFLS). RFLS was stimulated with Toll-like receptor 3 (TLR3) ligand polyinosinic:polycytidylic acid (poly I:C), a synthetic double-stranded RNA mimetic. Expression of interferon beta (IFN-β), MDA5, and CXCL10 was measured by real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR), western blotting, and enzyme-linked immunosorbent assay. A neutralizing antibody of IFN-β and siRNA-mediated MDA5 knockdown were used to determine the role of these molecules in regulating CXCL10 expression downstream of TLR3 signaling in RFLS. Poly I:C induced IFN-β, MDA5, and CXCL10 expression in a concentration- and time-dependent manner. IFN-β neutralizing antibody suppressed the expression of MDA5 and CXCL10, and knockdown of MDA5 decreased a part of CXCL10 expression (p < 0.001). The TLR3/IFN-β/CXCL10 axis may play a crucial role in the inflammatory responses in RA synovium, and MDA5 may be partially involved in this axis.


2007 ◽  
Vol 18 (11) ◽  
pp. 4317-4326 ◽  
Author(s):  
Hiroshi Qadota ◽  
Kristina B. Mercer ◽  
Rachel K. Miller ◽  
Kozo Kaibuchi ◽  
Guy M. Benian

By yeast two-hybrid screening, we found three novel interactors (UNC-95, LIM-8, and LIM-9) for UNC-97/PINCH in Caenorhabditis elegans. All three proteins contain LIM domains that are required for binding. Among the three interactors, LIM-8 and LIM-9 also bind to UNC-96, a component of sarcomeric M-lines. UNC-96 and LIM-8 also bind to the C-terminal portion of a myosin heavy chain (MHC), MHC A, which resides in the middle of thick filaments in the proximity of M-lines. All interactions identified by yeast two-hybrid assays were confirmed by in vitro binding assays using purified proteins. All three novel UNC-97 interactors are expressed in body wall muscle and by antibodies localize to M-lines. Either a decreased or an increased dosage of UNC-96 results in disorganization of thick filaments. Our previous studies showed that UNC-98, a C2H2 Zn finger protein, acts as a linkage between UNC-97, an integrin-associated protein, and MHC A in myosin thick filaments. In this study, we demonstrate another mechanism by which this linkage occurs: from UNC-97 through LIM-8 or LIM-9/UNC-96 to myosin.


Molecules ◽  
2021 ◽  
Vol 26 (24) ◽  
pp. 7461
Author(s):  
Claire K. Holley ◽  
Edward Cedrone ◽  
Duncan Donohue ◽  
Barry W. Neun ◽  
Daniela Verthelyi ◽  
...  

Understanding, predicting, and minimizing the immunogenicity of peptide-based therapeutics are of paramount importance for ensuring the safety and efficacy of these products. The so-called anti-drug antibodies (ADA) may have various clinical consequences, including but not limited to the alteration in the product’s distribution, biological activity, and clearance profiles. The immunogenicity of biotherapeutics can be influenced by immunostimulation triggered by the presence of innate immune response modulating impurities (IIRMIs) inadvertently introduced during the manufacturing process. Herein, we evaluate the applicability of several in vitro assays (i.e., complement activation, leukocyte proliferation, and cytokine secretion) for the screening of innate immune responses induced by ten common IIRMIs (Bacillus subtilis flagellin, FSL-1, zymosan, ODN2006, poly(I:C) HMW, poly(I:C) LMW, CLO75, MDP, ODN2216, and Escherichia coli O111:B4 LPS), and a model biotherapeutic Forteo™ (teriparatide). Our study identifies cytokine secretion from healthy human donor peripheral blood mononuclear cells (PBMC) as a sensitive method for the in vitro monitoring of innate immune responses to individual IIRMIs and teriparatide (TP). We identify signature cytokines, evaluate both broad and narrow multiplex cytokine panels, and discuss how the assay logistics influence the performance of this in vitro assay.


2021 ◽  
Author(s):  
Audrey Baylet ◽  
Raoul Vyumvuhore ◽  
Marine Laclaverie ◽  
Laëtitia Marchand ◽  
Carine Mainzer ◽  
...  

SummaryBackgroundCurrently, several biologics are used for the treatment of cutaneous pathologies such as atopic dermatitis (AD), psoriasis (PSO) or skin cancers. The main administration routes are subcutaneous and intravenous injections. However, little is known about antibody penetration through the skin.ObjectivesThe aim was to study the transcutaneous penetration of a reduced-size antibody as a single-chain variable fragment (scFv) compared to a whole antibody (Ab) and to determine its capacity to neutralize an inflammatory cytokine involved in AD such as human interleukin-4 (hIL-4).MethodsTranscutaneous penetration was evaluated by ex vivo studies on tape-stripped pig ear skin. Antibody visualization through the skin was measured by Raman microspectroscopy. In addition, hIL-4 neutralization was studied using two 2D models. First, embryonic alkaline phosphatase (SEAP) secretion by HEK-Blue™ IL-4/IL-13 cells, proportional to hIL-4 cells stimulation, was quantified by OD 620 nm measurement in presence or absence of an anti-hIL4 scFv or Ab. Then, normal human keratinocytes (NHKs) were stimulated with polyinosinic-polycytidylic acid (poly I:C) +/− hIL-4 and treated with anti-hIL4 scFv. Human Interleukin-8 (hIL-8) concentrations were determined in culture supernatants by ELISA.ResultsAfter 24h of application, analysis by Raman microspectroscopy showed that scFv penetrated into the upper dermis while Ab remained on the stratum corneum. In addition, the anti-hIL4 scFv showed better efficiency compared to Ab, with a neutralization percentage at 200 nM of 68% and 47%, respectively, in the HEK-Blue™ IL-4/IL-13 model. hIL-8 dosage in stimulated NHKs supernatants revealed that addition of scFv induced a dose-dependent hIL-4 neutralization.ConclusionsscFv penetrates through to the upper papillary dermis while Ab remains on the surface. The anti-hIL4 scFv neutralizes its target effectively in two 2D models suggesting its potential use as topical therapy for AD.


2002 ◽  
Vol 365 (1) ◽  
pp. 51-56 ◽  
Author(s):  
Isabel MAYORDOMO ◽  
Pascual SANZ

In order to identify proteins that interact with Bmh2, a yeast member of the 14-3-3 protein family, we performed a two-hybrid screening using LexA-Bmh2 as bait. We identified Fin1, a novel intermediate filament protein, as the protein that showed the highest degree of interaction. We also identified components of the vesicular transport machinery such as Gic2 and Msb3, proteins involved in transcriptional regulation such as Mbf1, Gcr2 and Reg2, and a variety of other different proteins (Ppt1, Lre1, Rps0A and Ylr177w). We studied the interaction between Bmh2 and Fin1 in more detail and found that Bmh2 only interacted with phosphorylated forms of Fin1. In addition, we showed that Glc7, the catalytic subunit of the protein phosphatase 1 complex, was also able to interact with Fin1.


2008 ◽  
Vol 389 (10) ◽  
Author(s):  
Hye Jin Yun ◽  
Jungsun Kwon ◽  
Wongi Seol

Abstract The constitutive androstane receptor (CAR) is a member of the nuclear receptor superfamily and plays an important role in the degradation of xenobiotics in the liver. Using yeast two-hybrid screening, we identified SF3a3, a 60-kDa subunit of the splicing factor 3a complex, as a specific CAR-interacting protein. We further confirmed their interaction by both co-immunoprecipitation and GST pull-down assay. Functional studies showed that overexpression of SF3a3 inhibited the reporter activity driven by a promoter containing CAR binding sequences by up to 50%, whereas reduced expression of SF3a3 activated the same reporter activity by approximately three-fold. The inhibitory function of SF3a3 is independent of the presence of TCPOBOP, a CAR ligand. These data suggest that SF3a3 functions as a co-repressor of CAR transcriptional activity, in addition to its canonical function.


Sign in / Sign up

Export Citation Format

Share Document