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1.
Exp Appl Acarol ; 74(2): 191-199, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29383532

ABSTRACT

Borrelia miyamotoi, a spirochete found in the hard tick Ixodes ricinus, is thought to cause relapsing fever. The disease caused by this bacterium can manifest with high fever, fatigue and other symptoms. It may also lead to central nervous system involvement with symptoms similar to meningoencephalitis. DNA from ticks from the greater Augsburg region in Germany was subjected to qPCR for Borrelia spp., followed by nested PCR and subsequent sequencing for species identification of the qPCR positive samples. From 112 ticks, 20 were found to be positive for Borrelia. The DNA sequenced showed 50% Borrelia afzelli, 15% Borrelia garinii, 5% Borrelia valaisiana and one sequence was identified as Borrelia miyamotoi. The positive identification of Borrelia miyamotoi is unlikely to be due to contamination. In conclusion, Borrelia miyamotoi has been found in a tick in the Augsburg region for the first time. This follows on from previous reports of a low incidence of this bacterium in southern Germany around Lake Constance and in the Munich region. This infectious agent should be taken into account when patients present with recurring fever or neurological symptoms which cannot be otherwise explained. Tick-borne relapsing fever should now be considered as a cause of such symptoms and medical professionals should contemplate differential Borrelia testing when presented with corresponding symptoms.


Subject(s)
Borrelia/isolation & purification , Borrelia/physiology , Ixodes/microbiology , Animals , Germany , Real-Time Polymerase Chain Reaction
2.
J Immunol ; 192(7): 3143-55, 2014 Apr 01.
Article in English | MEDLINE | ID: mdl-24574500

ABSTRACT

The molecular basis of TNF tolerance is poorly understood. In human monocytes we detected two forms of TNF refractoriness, as follows: absolute tolerance was selective, dose dependently affecting a small group of powerful effector molecules; induction tolerance represented a more general phenomenon. Preincubation with a high TNF dose induces both absolute and induction tolerance, whereas low-dose preincubation predominantly mediates absolute tolerance. In cells preincubated with the high TNF dose, we observed blockade of IκBα phosphorylation/proteolysis and nuclear p65 translocation. More prominent in cells preincubated with the high dose, reduced basal IκBα levels were found, accompanied by increased IκBα degradation, suggesting an increased IκBα turnover. In addition, a nuclear elevation of p50 was detected in tolerant cells, which was more visible following high-dose preincubation. TNF-induced phosphorylation of p65-Ser(536), p38, and c-jun was inhibited, and basal inhibitory p65-Ser(468) phosphorylation was increased in tolerant cells. TNF tolerance induced by the low preincubation dose is mediated by glycogen synthesis kinase-3, whereas high-dose preincubation-mediated tolerance is regulated by A20/glycogen synthesis kinase-3 and protein phosphatase 1-dependent mechanisms. To our knowledge, we present the first genome-wide analysis of TNF tolerance in monocytic cells, which differentially inhibits NF-κB/AP-1-associated signaling and shifts the kinase/phosphatase balance. These forms of refractoriness may provide a cellular paradigm for resolution of inflammation and may be involved in immune paralysis.


Subject(s)
Monocytes/immunology , NF-kappa B/immunology , Protein Phosphatase 1/immunology , Signal Transduction/immunology , Transcription Factor AP-1/immunology , Tumor Necrosis Factor-alpha/immunology , Blotting, Western , Cell Line, Tumor , Cells, Cultured , Dose-Response Relationship, Drug , Drug Tolerance/immunology , Glycogen Synthase Kinase 3/genetics , Glycogen Synthase Kinase 3/immunology , Glycogen Synthase Kinase 3/metabolism , HeLa Cells , Humans , I-kappa B Kinase/genetics , I-kappa B Kinase/immunology , I-kappa B Kinase/metabolism , Monocytes/drug effects , Monocytes/metabolism , NF-kappa B/genetics , NF-kappa B/metabolism , Oligonucleotide Array Sequence Analysis , Phosphorylation/drug effects , Phosphorylation/immunology , Protein Phosphatase 1/genetics , Protein Phosphatase 1/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction/drug effects , Signal Transduction/genetics , Time Factors , Transcription Factor AP-1/genetics , Transcription Factor AP-1/metabolism , Transcription Factor RelA/genetics , Transcription Factor RelA/immunology , Transcription Factor RelA/metabolism , Transcriptome/drug effects , Transcriptome/immunology , Tumor Necrosis Factor-alpha/pharmacology
3.
AJR Am J Roentgenol ; 202(2): 452-8, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24450691

ABSTRACT

OBJECTIVE: Preexisting renal impairment is a risk factor for contrast-induced nephropathy (CIN). In patients with creatinine in the upper normal level, cystatin C might be a more sensitive predictor of CIN than creatinine. Therefore, in this study, we investigated the usefulness of cystatin C to predict CIN. SUBJECTS AND METHODS: In 400 consecutive patients with creatinine baseline levels between 0.8 and 1.3 mg/dL undergoing coronary angiography (n = 200) or CT (n = 200), baseline values of cystatin C, creatinine, blood urea nitrogen (BUN) and risk factors of CIN were determined. Creatinine was also assessed 24 and 48 hours after contrast administration. RESULTS: Creatinine significantly (p < 0.001) increased after 24 hours and 48 hours compared with baseline (1.06 ± 0.28 and 1.07 ± 0.28 vs 0.99 ± 0.18 mg/dL). Fifty-three of 373 evaluable patients (14.2%) had an increase in creatinine of ≥ 25% or ≥ 0.5 mg/dL within 48 hours. CIN according to this definition was significantly more frequent after intraarterial contrast administration (38/190, 20%) compared with IV contrast administration (15/183, 8.2%; p = 0.001). CIN was predicted by baseline cystatin C (area under the receiver operating characteristic [ROC] curve [AUC], 0.715; p < 0.001), whereas creatinine, creatinine clearance, and BUN were not predictive. The best predictive capabilities were provided by cystatin C/creatinine-ratio (AUC, 0.826; p < 0.001). Multivariate regression analysis showed that intraarterial contrast administration (p = 0.002) and higher baseline cystatin C (p < 0.001) combined with low creatinine (p = 0.044) were independently associated with higher increases in creatinine within 48 hours after contrast administration. CONCLUSION: CIN in patients with creatinine within the upper normal range is significantly more frequent after intraarterial than after IV contrast administration. In these patients, renal impairment after contrast administration is independently predicted by cystatin C and cystatin C/creatinine-ratio, whereas BUN and creatinine were not predictive.


Subject(s)
Contrast Media/adverse effects , Creatinine/blood , Cystatin C/blood , Kidney Diseases/blood , Kidney Diseases/chemically induced , Aged , Area Under Curve , Blood Urea Nitrogen , Coronary Angiography , Female , Humans , Male , Prospective Studies , Time Factors
4.
J Pharm Sci ; 112(8): 2069-2078, 2023 Aug.
Article in English | MEDLINE | ID: mdl-36638959

ABSTRACT

These proceedings contain presentation summaries and discussion highlights from the University of Maryland Center of Excellence in Regulatory Science and Innovation (M-CERSI) Workshop on Co-processed API, held on July 13 and 14, 2022. This workshop examined recent advances in the use of co-processed active pharmaceutical ingredients as a technology to improve drug substance physicochemical properties and drug product manufacturing process robustness, and explored proposals for enabling commercialization of these transformative technologies. Regulatory considerations were discussed with a focus on the classification, CMC strategies, and CMC documentation supporting the use of this class of materials from clinical studies through commercialization. The workshop format was split between presentations from industry, academia and the FDA, followed by breakout sessions structured to facilitate discussion. Given co-processed API is a relatively new concept, the authors felt it prudent to compile these proceedings to gain further visibility to topics discussed and perspectives raised during the workshop, particularly during breakout discussions. Disclaimer: This paper reflects discussions that occurred among stakeholder groups, including FDA, on various topics. The topics covered in the paper, including recommendations, therefore, are intended to capture key discussion points. The paper should not be interpreted to reflect alignment on the different topics by the participants, and the recommendations provided should not be used in lieu of FDA published guidance or direct conversations with the Agency about a specific development program. This paper should not be construed to represent FDA's views or policies.

5.
J Exp Med ; 196(7): 887-96, 2002 Oct 07.
Article in English | MEDLINE | ID: mdl-12370251

ABSTRACT

The contribution of platelets to the process of atherosclerosis remains unclear. Here, we show in vivo that platelets adhere to the vascular endothelium of the carotid artery in ApoE(-)(/)(-) mice before the development of manifest atherosclerotic lesions. Platelet-endothelial cell interaction involved both platelet glycoprotein (GP)Ibalpha and GPIIb-IIIa. Platelet adhesion to the endothelium coincides with inflammatory gene expression and preceded atherosclerotic plaque invasion by leukocytes. Prolonged blockade of platelet adhesion in ApoE(-)(/)(-) mice profoundly reduced leukocyte accumulation in the arterial intima and attenuated atherosclerotic lesion formation in the carotid artery bifurcation, the aortic sinus, and the coronary arteries. These findings establish the platelet as a major player in initiation of the atherogenetic process.


Subject(s)
Arteriosclerosis/pathology , Platelet Adhesiveness/physiology , Animals , Apolipoproteins E/deficiency , Apolipoproteins E/genetics , Apolipoproteins E/physiology , Arteriosclerosis/blood , CD11b Antigen/blood , CD11b Antigen/genetics , Carotid Arteries/pathology , Carotid Arteries/physiopathology , Endothelium, Vascular/pathology , Endothelium, Vascular/physiopathology , Inflammation/pathology , Inflammation/physiopathology , Mice , Mice, Inbred C57BL , Mice, Knockout , Platelet Glycoprotein GPIIb-IIIa Complex/genetics
6.
Int J Pharm ; 512(2): 352-354, 2016 Oct 30.
Article in English | MEDLINE | ID: mdl-27001530

ABSTRACT

An increasing elderly population is leading to a change in the global demographics. This presents a new challenge to society and the pharmaceutical industry. This demographic shift is providing an opportunity for the pharmaceutical industry to meet the specific needs of the changing patient population. One issue that has been identified is defining what is meant by "an older patient", since this definition cannot be simply limited to chronological age. The fundamental purpose of the design and development process is to create a product that can be used by the patient group in a safe and efficacious manner. In the pharmaceutical industry ICH Q8 is used to guide the design and development of medicines. The process leads to the definition of the Quality Target Product Profile (QTPP) for a specific drug product and patient population. One can imagine a product with various presentations described in the QTPP which suit paediatrics, adults and older patients. It is recognised that designing medicines for smaller population groups will result in multiple presentations that could lead to smaller manufacturing batch sizes. In the short to medium term; dose flexibility, easy-to-swallow formulations, and easier access packaging are all factors under consideration. Dose flexibility could be achieved with various dosage forms such as oral liquids, mini-tablets, or multi-particulates. Whilst patient dosage preferences are beginning to be understood, further investigation is needed to balance the needs of the patient, care giver, prescriber, and payer. There also remain a number of challenges with the engineering solutions and delivery device for mini-tablets and multi-particulates (aside from filled capsules) to accurately and robustly deliver the dose, and issues with handling the device and the packaging for an older patient. It is also recognised that there are numerous challenges, not least of which is the definition of the older patient and a generic QTPP for an older patients' drug product. It is likely that there will be no simple solution or 'one-size-fits-all' approach in drug product development to resolve the complex issues presented by the ageing population.


Subject(s)
Chemistry, Pharmaceutical/methods , Drug Design , Drug Discovery/methods , Drug Industry/methods , Aged , Chemistry, Pharmaceutical/trends , Drug Discovery/trends , Drug Industry/trends , Humans
7.
Cell Signal ; 15(1): 1-7, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12401514

ABSTRACT

Transcription factors of the nuclear factor-kappaB (NF-kappaB)/Rel family play a crucial role in gene regulation during a variety of different cellular processes. This review focuses on the increasing knowledge of the role of NF-kappaB in skin physiology and pathology. Several studies demonstrate that NF-kappaB, or components of the system such as IkappaB kinase (IKK)-alpha, seem to be involved in epidermal development and differentiation. Furthermore, a dysregulation of NF-kappaB is suggested to play an important role in skin pathology, including proliferative disorders, e.g. psoriasis, inflammatory processes such as incontinentia pigmenti (IP), sunburn, Lyme disease, allergic contact dermatitis and autoimmune diseases, as well as also in skin carcinogenesis. However, although the knowledge concerning the role of NF-kappaB in the homeostasis of the skin is steadily increasing, many more questions need to be answered.


Subject(s)
NF-kappa B/physiology , Skin Diseases/etiology , Skin Physiological Phenomena , Animals , Mice , Signal Transduction , Skin Diseases/immunology , Skin Diseases/pathology , Skin Neoplasms/etiology
8.
Atherosclerosis ; 165(1): 79-88, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12208473

ABSTRACT

Chlamydia pneumoniae may be involved in atherosclerosis by inducing inflammation as well as LDL oxidation. The transcription factor NF-kappa B is found in an active state in atherosclerotic lesions. This study examined the effect of C. pneumoniae exposure on the NF-kappa B system in human monocytic lineage cells. Short exposure to C. pneumoniae as well as chlamydial heat shock protein 60 activated NF-kappa B, accompanied by increased cytokine production. Incubation with C. pneumoniae-induced depletion of I kappa B-alpha and later I kappa B-epsilon which was preceded by I kappa B kinase complex activation. 4-Hydroxynonenal, an aldehyde LDL oxidation product, was shown to inhibit C. pneumoniae induced NF-kappa B activation by preventing I kappa B phosphorylation/proteolysis. During long-term incubation with C. pneumoniae I kappa B-alpha returned to baseline, whereas the levels of I kappa B-epsilon and p65 were upregulated. Interestingly, long-term preincubation with C. pneumoniae selectively prevented restimulation by this microorganism, which appears to be at least partly facilitated by inhibition of I kappa B proteolysis. C. pneumoniae-induced NF-kappa B activation as well as the inhibition of that effect under certain conditions may contribute to chronic inflammation with potential relevance to vascular disease.


Subject(s)
Aldehydes/pharmacology , Chlamydophila pneumoniae/physiology , I-kappa B Proteins/metabolism , NF-kappa B/metabolism , Blotting, Western , Cells, Cultured , Chlamydophila pneumoniae/drug effects , Culture Media , Cytokines/analysis , Cytokines/metabolism , Electrophoresis, Polyacrylamide Gel , Enzyme Activation , Enzyme-Linked Immunosorbent Assay , Humans , Monocytes , Sensitivity and Specificity , Signal Transduction
9.
Thromb Haemost ; 88(2): 307-14, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12195705

ABSTRACT

Activated platelets alter endothelial chemotactic and adhesive properties. Transient interaction of alpha-thrombin-activated platelets with endothelial cells is sufficient to induce secretion of the NF-kappa B-regulated chemokine MCP-1. To evaluate upstream signaling events in platelet-induced NF-kappa B activation, we compared the effect of platelets, IL-1 beta or TNF-alpha on I kappa B kinase (IKK) complex activation and I kappa B phosphorylation/proteolysis. Kinase assays demonstrated that platelets induced a slow increase in IKK activity over 30 min, which was similar, but not identical, to IL-1 beta, whereas TNF-alpha elicited a rapid induction of IKK. Differential effects were also found on I kappa B-alpha/epsilon degradation, while IKK levels were unaffected. Furthermore, overexpression of kinase-inactive IKK-beta KA, as well as NIKKA, inhibited platelet- or IL-1 beta-induced kappa B-, MCP-1- or VCAM-1-dependent transcription. Using adeno-associated virus particles for cell transduction, we found that IKK-beta KA substantially reduced stimulus-induced MCP-1 secretion. Platelet-induced signaling and resulting endothelial gene expression may play a role in early atherogenesis as well as plaque progression/destabilization.


Subject(s)
Blood Platelets/physiology , Cell Communication , Chemokine CCL2/biosynthesis , Endothelium, Vascular/metabolism , Protein Serine-Threonine Kinases/metabolism , Endothelium, Vascular/cytology , Gene Expression Regulation , Humans , I-kappa B Kinase , Interleukin-1/pharmacology , NF-kappa B/metabolism , Platelet Activation , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/physiology , Transcription, Genetic , Transfection , Tumor Necrosis Factor-alpha/pharmacology , Umbilical Veins/cytology
10.
Thromb Res ; 110(4): 187-94, 2003 Jun 01.
Article in English | MEDLINE | ID: mdl-14512080

ABSTRACT

OBJECTIVE: Exposure of the subendothelium to flowing blood following rupture of atherosclerotic lesions or during balloon angioplasty initiates platelet adhesion to the vascular wall. Because activated platelets release proinflammatory mediators (e.g., interleukin (IL)-1beta) and secrete growth factors, platelet adhesion to the subendothelial matrix might contribute to the recruitment of inflammatory cells and promote migration and proliferation of vascular smooth muscle cells (SMCs). METHODS AND RESULTS: Here, we demonstrate that incubation of cultured monolayers of aortic SMCs with alpha-thrombin-activated platelets significantly enhances the secretion of monocyte chemoattractant protein-1 (MCP-1) (P<0.05) and promotes SMC migration (P<0.05). Platelet-induced secretion of MCP-1 was abolished by anti-IL-1alpha and beta monoclonal antibodies or the IL-1 receptor antagonist (IL-1RA). In contrast, platelet-mediated SMC migration was attenuated only by anti-platelet-derived growth factor (PDGF)-mAb but not by IL-1RA. Correspondingly, recombinant human interleukin-1 (rhIL-1) beta increased MCP release by SMCs but had no effect on SMC migration. Platelet-mediated MCP secretion by SMCs involved the activation and nuclear translocation of the transcription factor nuclear factor-kappaB (NF-kappaB). CONCLUSION: Therefore, platelet adhesion to the subendothelium increases the chemotactic and migratory properties of SMC and is likely to contribute substantially to the process of atherosclerosis and vessel (re-)stenosis.


Subject(s)
Aorta , Blood Platelets/metabolism , Chemokine CCL2/metabolism , Muscle, Smooth, Vascular/metabolism , Platelet Activation , Aorta/cytology , Cell Adhesion/physiology , Cells, Cultured , Humans , Inflammation
11.
Biosens Bioelectron ; 25(1): 198-203, 2009 Sep 15.
Article in English | MEDLINE | ID: mdl-19632822

ABSTRACT

The serum determination of circulating anti-double-stranded (ds)DNA autoantibodies is a routine measure for the laboratory diagnosis of systemic lupus erythematosus. Since available assays differ substantially and no feasible calibrator is available, the aim of this study was to evaluate a recently introduced surface plasmon resonance (SPR) biosensor chip for binding studies between dsDNA and anti-dsDNA autoantibodies and to demonstrate its usefulness for the characterization of new monoclonal antibody (mAb) standards and standardization of assays. We characterized two human and one murine monoclonal anti-dsDNA antibodies by measuring the kinetic on- and off-rates using the biosensor and calculating functional affinity (avidity) as the ratio of these. Obtained equilibrium dissociation constants were verified by an independent method and inhibition experiments were performed to determine reactivities to DNA of various length and composition. While all mAbs exhibited comparable avidities, which could be confirmed by gel shift experiments, one of them proved to have slower association and dissociation kinetics. This was the only mAb providing positive results in the Farr RIA. In inhibition experiments with ss- and ds-oligonucleotides 10, 24 and 42 bp in length, the mAbs acted substantially different. The study demonstrates how putative standards for the anti-dsDNA determination can be characterized using SPR biosensor technology. Our results suggest that kinetic rate constants seem to be decisive in explaining the behaviour of mAbs. Different reactivities to various DNA species should be taken into account with respect to varying DNA sources in commonly used laboratory assays.


Subject(s)
Antibodies, Antinuclear , Antibodies, Monoclonal , Lupus Erythematosus, Systemic/diagnosis , Surface Plasmon Resonance , Animals , Antibodies, Antinuclear/immunology , Antibodies, Monoclonal/immunology , Binding Sites, Antibody , Binding, Competitive , DNA/immunology , Electrophoretic Mobility Shift Assay , Humans , Kinetics , Lupus Erythematosus, Systemic/immunology , Mice
12.
Cell Signal ; 21(12): 1918-24, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19733238

ABSTRACT

NF-kappaB and C/EBPbeta proteins are involved in the regulation of genes which play a role in inflammation, immunity and malignant processes. The present study focuses on the question of how these systems cross talk "upstream" of the promoter level and investigates the regulation of NF-kappaB-associated signalling by C/EBPbeta. In C/EBPbeta(ko) macrophage-like cells stimulated with TNF or LPS a reduced 3kappaB-dependent transcription was detected compared to the wild type. This was accompanied by elevated nuclear p65 and NF-kappaB activity in the presence of C/EBPbeta. In addition, overexpression of C/EBPbeta in HeLa cells increased the nuclear level of coexpressed p65. Remarkably, the constitutive level of IkappaB-alpha was significantly higher in C/EBPbeta(ko) cells; and this higher level was readjusted following stimulus-induced proteolysis. The IkappaB-alpha protein stability was comparable in both macrophage-like cell types with a somewhat higher stability in unstimulated C/EBPbeta(ko) cells. Following stimulation with TNF, higher IkappaB-alpha mRNA levels were induced in C/EBPbeta(ko) cells. The autoregulatory recovery of IkappaB-alpha protein following activation was completely blocked by transcriptional inhibition, regardless if C/EBPbeta was present. Finally, we showed that C/EBPbeta overexpression in HeLa cells blocked TNF-mediated inducibility of the IkappaB-alpha promoter. Taken together, our results indicate that regulation of the IkappaB-alpha level is one of the underlying mechanisms by which C/EBPbeta controls NF-kappaB-associated signalling. C/EBPbeta may belong to the group of proteins in the regulatory machinery which adjusts the IkappaB-alpha level in different cell types under various conditions with physiological and pathophysiological implications.


Subject(s)
CCAAT-Enhancer-Binding Protein-beta/metabolism , I-kappa B Proteins/metabolism , NF-kappa B/metabolism , CCAAT-Enhancer-Binding Protein-beta/genetics , Cell Nucleus/metabolism , Gene Expression Regulation , Gene Knockdown Techniques , HeLa Cells , Humans , I-kappa B Proteins/genetics , Macrophages/metabolism , NF-KappaB Inhibitor alpha , Promoter Regions, Genetic , Protein Stability , RNA, Messenger/genetics , Transcription, Genetic , Tumor Necrosis Factor-alpha/metabolism , eIF-2 Kinase/metabolism
13.
J Cell Sci ; 115(Pt 20): 3879-88, 2002 Oct 15.
Article in English | MEDLINE | ID: mdl-12244126

ABSTRACT

Endothelial migration on extracellular matrix is regulated by integrins and proteolysis. Previous studies showed that beta(3)-integrins regulate expression of the urokinase-type plasminogen activator receptor (uPAR) through outside-in signalling involving the cytoplasmic domain. Here we show that overexpression of the integrin-binding protein beta(3)-endonexin decreased uPAR promoter (-398 base-pair fragment) activity that is constitutively active in endothelial cells. Mutation of the NF-kappaB promoter binding site (-45 bp) impaired the ability of beta(3)-endonexin to downregulate uPAR promoter activity. Immunoprecipitation studies showed that beta(3)-endonexin interacts directly with the p50/p65 transactivation complex and thereby inhibits binding of kappaB oligonucleotides to the p50/p65 complex. Moreover, binding of beta(3)-endonexin to p50 was inhibited in the presence of kappaB but not mutated kappaB oligonucleotides, suggesting a sterical competition between beta(3)-endonexin and kappaB DNA for the p50/p65 complex. We therefore propose that beta(3)-endonexin acts as regulator of uPAR expression in beta(3)-integrin-mediated endothelial cell migration through direct interaction with p50/p65. Since NF-kappaB regulates the expression of matrix degrading enzymes, the present results define a role of beta(3)-endonexin in regulating beta(3)-integrin-mediated adhesion and pericellular proteolysis.


Subject(s)
Gene Expression Regulation , NF-kappa B/antagonists & inhibitors , Proteins/metabolism , Receptors, Cell Surface/metabolism , Trans-Activators/antagonists & inhibitors , Animals , Binding Sites , CHO Cells , Cell Line , Cell Nucleus/metabolism , Cricetinae , Cytoplasm/metabolism , Down-Regulation , Endothelium, Vascular/cytology , Green Fluorescent Proteins , Humans , Luminescent Proteins/metabolism , Mutation , NF-kappa B/genetics , NF-kappa B/metabolism , Nuclear Proteins , Promoter Regions, Genetic , Receptors, Cell Surface/genetics , Receptors, Urokinase Plasminogen Activator , Recombinant Proteins/metabolism , Sequence Deletion , Trans-Activators/genetics , Trans-Activators/metabolism , Transcription, Genetic , Transcriptional Activation , Umbilical Veins/cytology
14.
J Biol Chem ; 279(36): 37452-60, 2004 Sep 03.
Article in English | MEDLINE | ID: mdl-15226300

ABSTRACT

The IkappaB kinase (IKK) complex is one major step in the regulation of the NF-kappaB/Rel system that is involved in inflammatory and immune responses as well as in proliferation and apoptosis. At present it is not clear whether besides the "classical" IKKalpha-IKKbeta-IKKgamma configuration additional complexes exist in vivo that solely contain IKKbeta and IKKgamma (without IKKalpha). In the current study we were able to demonstrate in monocytic cells that endogenous complexes, which only include IKKbeta as the kinase-active molecule do indeed exist in vivo and that these complexes contain IKKgamma as an additional component. Furthermore, we showed that these IKKbeta-IKKgamma complexes are involved in mainstream NF-kappaB activation cascades because they can be activated by tumor necrosis factor. In contrast, these subcomplexes appear not to participate in NIK-dependent pathways. As a next step we showed that exogenous IKKbeta-IKKgamma complexes can be formed in an intact cell by overexpression and that these artificial complexes fulfill the requirement for participation in regular signaling. Finally, in the absence of IKKalpha we found a retarded proteolysis of IkappaBalpha, but not of IkappaB in, which is associated with a reduced IKK activity. Differential pathways represented by various IKK subcomplexes may open attractive possibilities in treatment of inflammation or cancer allowing specific therapeutic intervention.


Subject(s)
Monocytes/metabolism , Protein Serine-Threonine Kinases/metabolism , Signal Transduction , Cell Line , Humans , Hydrolysis , I-kappa B Kinase , Protein Binding
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