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Sample records for cell-adhesive peptides derived

  1. The Neural Cell Adhesion Molecule-Derived Peptide FGL Facilitates Long-Term Plasticity in the Dentate Gyrus in Vivo

    Science.gov (United States)

    Dallerac, Glenn; Zerwas, Meike; Novikova, Tatiana; Callu, Delphine; Leblanc-Veyrac, Pascale; Bock, Elisabeth; Berezin, Vladimir; Rampon, Claire; Doyere, Valerie

    2011-01-01

    The neural cell adhesion molecule (NCAM) is known to play a role in developmental and structural processes but also in synaptic plasticity and memory of the adult animal. Recently, FGL, a NCAM mimetic peptide that binds to the Fibroblast Growth Factor Receptor 1 (FGFR-1), has been shown to have a beneficial impact on normal memory functioning, as…

  2. The Neural Cell Adhesion Molecule-Derived Peptide FGL Facilitates Long-Term Plasticity in the Dentate Gyrus in Vivo

    Science.gov (United States)

    Dallerac, Glenn; Zerwas, Meike; Novikova, Tatiana; Callu, Delphine; Leblanc-Veyrac, Pascale; Bock, Elisabeth; Berezin, Vladimir; Rampon, Claire; Doyere, Valerie

    2011-01-01

    The neural cell adhesion molecule (NCAM) is known to play a role in developmental and structural processes but also in synaptic plasticity and memory of the adult animal. Recently, FGL, a NCAM mimetic peptide that binds to the Fibroblast Growth Factor Receptor 1 (FGFR-1), has been shown to have a beneficial impact on normal memory functioning, as…

  3. The fibroblast growth factor receptor (FGFR) agonist FGF1 and the neural cell adhesion molecule-derived peptide FGL activate FGFR substrate 2alpha differently

    DEFF Research Database (Denmark)

    Chen, Yongshuo; Li, Shizhong; Berezin, Vladimir

    2010-01-01

    Activation of fibroblast growth factor (FGF) receptors (FGFRs) both by FGFs and by the neural cell adhesion molecule (NCAM) is crucial in the development and function of the nervous system. We found that FGFR substrate 2alpha (FRS2alpha), Src homologous and collagen A (ShcA), and phospholipase......-Cgamma (PLCgamma) were all required for neurite outgrowth from cerebellar granule neurons (CGNs) induced by FGF1 and FGL (an NCAM-derived peptide agonist of FGFR1). Like FGF1, FGL induced tyrosine phosphorylation of FGFR1, FRS2alpha, ShcA, and PLCgamma in a time- and dose-dependent manner. However, the activation...... of FRS2alpha by FGL was significantly lower than the activation by FGF1, indicating a differential signaling profile induced by NCAM compared with the cognate growth factor....

  4. The neural cell adhesion molecule-derived peptide, FGL, attenuates lipopolysaccharide-induced changes in glia in a CD200-dependent manner

    DEFF Research Database (Denmark)

    Cox, F F; Berezin, V; Bock, E

    2013-01-01

    Fibroblast growth loop (FGL) is a neural cell adhesion molecule (NCAM)-mimetic peptide that mimics the interaction of NCAM with fibroblast growth factor receptor (FGFR). FGL increases neurite outgrowth and promotes neuronal survival in vitro, and it has also been shown to have neuroprotective eff...

  5. Neuritogenic and survival-promoting effects of the P2 peptide derived from a homophilic binding site in the neural cell adhesion molecule

    DEFF Research Database (Denmark)

    Pedersen, Martin V; Køhler, Lene B; Ditlevsen, Dorte K

    2004-01-01

    The neural cell adhesion molecule (NCAM) plays a pivotal role in neural development, regeneration, and plasticity. NCAM mediates adhesion and subsequent signal transduction through NCAM-NCAM binding. Recently, a peptide ligand termed P2 corresponding to a 12-amino-acid sequence in the FG loop...

  6. The neural cell adhesion molecule-derived peptide FGL facilitates long-term plasticity in the dentate gyrus in vivo

    DEFF Research Database (Denmark)

    Dallérac, Glenn; Zerwas, Meike; Novikova, Tatiana

    2011-01-01

    and maintenance of synaptic plasticity in the dentate gyrus (DG) in vivo. For this, we first assessed the effect of the FGL peptide on synaptic functions at perforant path-dentate gyrus synapses in the anesthetized rat. FGL, or its control inactive peptide, was injected locally 60 min before applying high...

  7. A neural cell adhesion molecule-derived peptide reduces neuropathological signs and cognitive impairment induced by Abeta25-35

    DEFF Research Database (Denmark)

    Klementiev, B; Novikova, T; Novitskaya, V;

    2007-01-01

    By means of i.c.v. administration of preaggregated oligomeric beta-amyloid (Abeta)25-35 peptide it was possible in rats to generate neuropathological signs related to those of early stages of Alzheimer's disease (AD). Abeta25-35-administration induced the deposition of endogenously produced amyloid...

  8. A neural cell adhesion molecule-derived fibroblast growth factor receptor agonist, the FGL-peptide, promotes early postnatal sensorimotor development and enhances social memory retention

    DEFF Research Database (Denmark)

    Secher, Thomas; Novitskaia, V; Berezin, Vladimir

    2006-01-01

    The neural cell adhesion molecule (NCAM) belongs to the immunoglobulin (Ig) superfamily and is composed extracellularly of five Ig-like and two fibronectin type III (F3) modules. It plays a pivotal role in neuronal development and synaptic plasticity. NCAM signals via a direct interaction...... of coordination skills. In adult animals s.c. administration of FGL resulted in a prolonged retention of social memory. We found that FGL rapidly penetrated into the blood and cerebrospinal fluid after both intranasal and s.c. administration and remained detectable in the fluids for up to 5 hours....

  9. A peptide derived from a trans-homophilic binding site in neural cell adhesion molecule induces neurite outgrowth and neuronal survival

    DEFF Research Database (Denmark)

    Køhler, Lene B; Soroka, Vladislav; Korshunova, Irina

    2010-01-01

    The neural cell adhesion molecule (NCAM) plays a key role in neural development, regeneration, and synaptic plasticity. The crystal structure of a fragment of NCAM comprising the three N-terminal immunoglobulin (Ig)-like modules indicates that the first and second Ig modules bind to each other...... module. It promoted survival of cultured cerebellar granule neurons (CGNs) and also induced neurite extension in cultures of dopaminergic neurons and CGNs; the latter effect was shown to be dependent on NCAM expression, indicating that plannexin mimics the neuritogenic effect of homophilic NCAM binding....

  10. Triple Effect of Mimetic Peptides Interfering with Neural Cell Adhesion Molecule Homophilic Cis Interactions

    DEFF Research Database (Denmark)

    Li, S. Z.; Kolkova, Kateryna; Rudenko, Olga;

    2005-01-01

    The neural cell adhesion molecule (NCAM) is pivotal in neural development, regeneration, and learning. Here we characterize two peptides, termed P1-B and P2, derived from the homophilic binding sites in the first two N-terminal immunoglobulin (Ig) modules of NCAM, with regard to their effects...... on neurite extension and adhesion. To evaluate how interference of these mimetic peptides with NCAM homophilic interactions in cis influences NCAM binding in trans, we employed a coculture system in which PC12-E2 cells were grown on monolayers of fibroblasts with or without NCAM expression and the rate...... of neurite outgrowth subsequently was analyzed. P2, but not P1-B, induced neurite outgrowth in the absence of NCAM binding in trans. When PC12-E2 cells were grown on monolayers of NCAM-expressing fibroblasts, the effect of both P1-B and P2 on neurite outgrowth was dependent on peptide concentrations. P1-B...

  11. Amyloid-beta induced CA1 pyramidal cell loss in young adult rats is alleviated by systemic treatment with FGL, a neural cell adhesion molecule-derived mimetic peptide.

    Directory of Open Access Journals (Sweden)

    Nicola J Corbett

    Full Text Available Increased levels of neurotoxic amyloid-beta in the brain are a prominent feature of Alzheimer's disease. FG-Loop (FGL, a neural cell adhesion molecule-derived peptide that corresponds to its second fibronectin type III module, has been shown to provide neuroprotection against a range of cellular insults. In the present study impairments in social recognition memory were seen 24 days after a 5 mg/15 µl amyloid-beta(25-35 injection into the right lateral ventricle of the young adult rat brain. This impairment was prevented if the animal was given a systemic treatment of FGL. Unbiased stereology was used to investigate the ability of FGL to alleviate the deleterious effects on CA1 pyramidal cells of the amyloid-beta(25-35 injection. NeuN, a neuronal marker (for nuclear staining was used to identify pyramidal cells, and immunocytochemistry was also used to identify inactive glycogen synthase kinase 3beta (GSK3β and to determine the effects of amyloid-beta(25-35 and FGL on the activation state of GSK3β, since active GSK3β has been shown to cause a range of AD pathologies. The cognitive deficits were not due to hippocampal atrophy as volume estimations of the entire hippocampus and its regions showed no significant loss, but amyloid-beta caused a 40% loss of pyramidal cells in the dorsal CA1 which was alleviated partially by FGL. However, FGL treatment without amyloid-beta was also found to cause a 40% decrease in CA1 pyramidal cells. The action of FGL may be due to inactivation of GSK3β, as an increased proportion of CA1 pyramidal neurons contained inactive GSK3β after FGL treatment. These data suggest that FGL, although potentially disruptive in non-pathological conditions, can be neuroprotective in disease-like conditions.

  12. Dennexin peptides modeled after the homophilic binding sites of the neural cell adhesion molecule (NCAM) promote neuronal survival, modify cell adhesion and impair spatial learning

    DEFF Research Database (Denmark)

    Køhler, Lene B; Christensen, Claus; Rossetti, Clara

    2010-01-01

    Neural cell adhesion molecule (NCAM)-mediated cell adhesion results in activation of intracellular signaling cascades that lead to cellular responses such as neurite outgrowth, neuronal survival, and modulation of synaptic activity associated with cognitive processes. The crystal structure...... between Ig1 and Ig3 and between Ig2 and Ig2, respectively, observed in the crystal structure. Although the two dennexin peptides differed in amino acid sequence, they both modulated cell adhesion, reflected by inhibition of NCAM-mediated neurite outgrowth. Both dennexins also promoted neuronal survival...

  13. Short Peptides Enhance Single Cell Adhesion and Viability onMicroarrays

    Energy Technology Data Exchange (ETDEWEB)

    Veiseh, Mandana; Veiseh, Omid; Martin, Michael C.; Asphahani,Fareid; Zhang, Miqin

    2007-01-19

    Single cell patterning holds important implications forbiology, biochemistry, biotechnology, medicine, and bioinformatics. Thechallenge for single cell patterning is to produce small islands hostingonly single cells and retaining their viability for a prolonged period oftime. This study demonstrated a surface engineering approach that uses acovalently bound short peptide as a mediator to pattern cells withimproved single cell adhesion and prolonged cellular viabilityon goldpatterned SiO2 substrates. The underlying hypothesis is that celladhesion is regulated bythe type, availability, and stability ofeffective cell adhesion peptides, and thus covalently bound shortpeptides would promote cell spreading and, thus, single cell adhesion andviability. The effectiveness of this approach and the underlyingmechanism for the increased probability of single cell adhesion andprolonged cell viability by short peptides were studied by comparingcellular behavior of human umbilical cord vein endothelial cells on threemodelsurfaces whose gold electrodes were immobilized with fibronectin,physically adsorbed Arg-Glu-Asp-Val-Tyr, and covalently boundLys-Arg-Glu-Asp-Val-Tyr, respectively. The surface chemistry and bindingproperties were characterized by reflectance Fourier transform infraredspectroscopy. Both short peptides were superior to fibronectin inproducing adhesion of only single cells, whereas the covalently boundpeptide also reduced apoptosis and necrosisof adhered cells. Controllingcell spreading by peptide binding domains to regulate apoptosis andviability represents a fundamental mechanism in cell-materialsinteraction and provides an effective strategy in engineering arrays ofsingle cells.

  14. Comparison of the solution conformations of a cell-adhesive peptide LBE and its reverse sequence EBL.

    Science.gov (United States)

    Jois, S D; Hughes, R; Siahaan, T J

    1999-12-01

    T-cell adhesion is mediated by an ICAM-1/LFA-1 interaction; this interaction plays a crucial role in T-cell activation during immune response. LBE peptide, which is derived from the beta-subunit of LFA-1, has been shown to inhibit ICAM-1/LFA-1-mediated T-cell adhesion. In this work, we studied the solution conformations of LBE peptide and its reverse sequence (EBL) by NMR, CD and molecular dynamics simulations. Reverse peptides have been used as controls in biological studies. The effect of reversing the sequence of LBE to EBL peptides on their respective conformations is important in understanding their biological properties in vitro or in vivo. The NMR studies for these peptides were carried out in water and in TFE/water solvent systems. In 40% TFE/water, both peptides exhibited helical conformation. CD studies suggested that the LBE exhibits 30% helical conformation, while the EBL exhibits 20% helical conformation. From the NMR and MD simulation studies, it was evident that the peptides exhibited a stable helical conformation; a stable helical structure was found at Leu6 to Leu15 for LBE and at Gly9 to Leu17 for EBL. The helical conformations of LBE and EBL may be in equilibrium with other possible conformers; the other conformers contain loop and turn structures. Both peptides bind to divalent cations because the LBE is derived from the cation-binding region of the LFA-1. This study shows that reversing the peptide sequence did not alter the secondary structure of the corresponding sequence. Hence, caution must be exercised when using reverse peptides as controls in biological studies. This report will improve our ability to design a better inhibitor of ICAM-1/LFA-1 interaction.

  15. Immobilization of RGD Peptides onto Decellularized Valve Scaffolds to Promote Cell Adhesion

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Porcine aortic valves were decellularized with trypsinase/EDTA and Triton-100. With the help of a coupling reagent Sulfo-LC-SPDP, the biological valve scaffolds were immobilized with one of RGD(arginine-glycine-aspartic acid) containing peptides, called GRGDSPC peptide. Myofibroblasts harvested from rats were seeded onto them. Based on the spectra of X-ray photoelectron spectroscopy, we could find conjugation of GRGDSPC peptide and the scaffolds. Cell count by both microscopy and MTT assay showed that myofibroblasts were easier to adhere to the modified scaffolds. It is proved that it is feasible to immobilize RGD peptides onto decellularized valve scaffolds, and effective to promote cell adhesion, which is beneficial for constructing tissue engineering heart valves in vitro.

  16. Cell adhesive peptides functionalized on CoCr alloy stimulate endothelialization and prevent thrombogenesis and restenosis.

    Science.gov (United States)

    Castellanos, Maria Isabel; Guillem-Marti, Jordi; Mas-Moruno, Carlos; Díaz-Ricart, Maribel; Escolar, Ginés; Ginebra, Maria Pau; Gil, Francisco Javier; Pegueroles, Marta; Manero, Jose María

    2017-04-01

    Immobilization of bioactive peptide sequences on CoCr surfaces is an effective route to improve endothelialization, which is of great interest for cardiovascular stents. In this work, we explored the effect of physical and covalent immoblization of RGDS, YIGSR and their equimolar combination peptides on endothelial cells (EC) and smooth muscle cell (SMC) adhesion and on thrombogenicity. We extensively investigated using RT-qPCR, the expression by ECs cultured on functionalised CoCr surfaces of different genes. Genes relevant for adhesion (ICAM-1 and VCAM-1), vascularization (VEGFA, VEGFR-1 and VEGFR-2) and anti-thrombogenicity (tPA and eNOS) were over-expressed in the ECs grown to covalently functionalized CoCr surfaces compared to physisorbed and control surfaces. Pro-thrombogenic genes expression (PAI-1 and vWF) decreased over time. Cell co-cultures of ECs/SMCs found that functionalization increased the amount of adhered ECs onto modified surfaces compared to plain CoCr, independently of the used peptide and the strategy of immobilization. SMCs adhered less compared to ECs in all surfaces. All studied peptides showed a lower platelet cell adhesion compared to TCPS. Covalent functionalization of CoCr surfaces with an equimolar combination of RGDS and YIGSR represented prevailing strategy to enhance the early stages of ECs adhesion and proliferation, while preventing SMCs and platelet adhesion. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 973-983, 2017.

  17. Single-step immobilization of cell adhesive peptides on a variety of biomaterial substrates via tyrosine oxidation with copper catalyst and hydrogen peroxide.

    Science.gov (United States)

    Kakinoki, Sachiro; Yamaoka, Tetsuji

    2015-04-15

    Immobilization of biologically active peptides which were isolated from extracellular matrix proteins is a powerful strategy for the design and functionalization of biomaterial substrates. However, the method of peptide immobilization was restricted, that is, peptide is often immobilized through the reactive groups inherent in substrates with multistep reactions. Here, we report a single-step immobilization of fibronectin-derived cell adhesive peptide (Arg-Glu-Asp-Val; REDV) onto polymer materials by use of tyrosine oxidation with copper catalyst and hydrogen peroxide. REDV peptide was successfully immobilized on tissue culture polystyrene, poly(ethylene terephthalate), poly(vinyl chloride), expanded-poly(tetrafluoroethylene), and poly(l-lactic acid), resulting in enhanced adhesion of human umbilical vein endothelial cells. This method is a single-step reaction under very mild conditions and is available for the biological functionalization of various medical devices.

  18. Neurite outgrowth induced by a synthetic peptide ligand of neural cell adhesion molecule requires fibroblast growth factor receptor activation

    DEFF Research Database (Denmark)

    Rønn, L C; Doherty, P; Holm, A;

    2000-01-01

    The neural cell adhesion molecule NCAM is involved in axonal outgrowth and target recognition in the developing nervous system. In vitro, NCAM-NCAM binding has been shown to induce neurite outgrowth, presumably through an activation of fibroblast growth factor receptors (FGFRs). We have recently...... identified a neuritogenic ligand, termed the C3 peptide, of the first immunoglobulin (lg) module of NCAM using a combinatorial library of synthetic peptides. Here we investigate whether stimulation of neurite outgrowth by this synthetic ligand of NCAM involves FGFRs. In primary cultures of cerebellar neurons...... from wild-type mice, the C3 peptide stimulated neurite outgrowth. This response was virtually absent in cultures of cerebellar neurons from transgenic mice expressing a dominant-negative form of the FGFR1. Likewise, in PC12E2 cells transiently expressing a dominant-negative form of the mouse FGFR1...

  19. Cell adhesion and polarisation on molecularly defined spacing gradient surfaces of cyclic RGDfK peptide patches.

    Science.gov (United States)

    Hirschfeld-Warneken, Vera C; Arnold, Marco; Cavalcanti-Adam, Ada; López-García, Mónica; Kessler, Horst; Spatz, Joachim P

    2008-09-01

    In vivo cell migration and location are orchestrally guided by soluble and bound chemical gradients. Here, gradients of extracellular matrix molecules are formed synthetically by the combination of a surface nanopatterning technique called block copolymer nanolithography (BCN) and a biofunctionalisation technique. A modified substrate dip-coating process of BCN allows for the formation of precise molecular gradients of cyclic RGDfK peptide patches at interfaces, which are presented to cells for testing cell adhesion and polarisation. Surfaces formed by BCN consist of hexagonally ordered gold dot patterns with a gradient in particle spacing. Each dot serves as a chemical anchor for the binding of cyclic RGDfK peptides, which are specifically recognised by alpha(v)beta(3) integrins. Due to steric hindrance only up to one integrin binds to one functionalised gold dot which forms a peptide patch spacing. We demonstrate how cell morphology, adhesion area, actin and vinculin distribution as well as cell body polarisation are influenced by the peptide patch spacing gradient. As a consequence, these gradients of adhesive ligands induce cell orientation towards smaller particle spacing when the gradient strength is 15nm/mm at least. This implicates that an adherent cell's sensitivity to differentiate between ligand patch spacing is approximately 1nm across the cell body.

  20. Endothelial cell adhesion and proliferation to PEGylated polymers with covalently linked RGD peptides.

    Science.gov (United States)

    Wang, Xin; Heath, Daniel E; Cooper, Stuart L

    2012-03-01

    A nonfouling peptide grafted polymer was synthesized that can promote endothelial cell (EC) binding. The polymer was composed of hexyl methacrylate, methyl methacrylate, poly(ethylene glycol) methacrylate, and CGRGDS peptide. The peptide was incorporated into the polymer system either by a chain transfer reaction or by coupling to an acrylate-PEG-N-hydroxysuccinimide (NHS) comonomer. The introduction of PEG chains minimizes protein adsorption. Human umbilical vein ECs and endothelial colony forming cells were cultured on these surfaces in short term and long-term studies. A difference in number and morphology of ECs was observed depending on the method of peptide incorporation. Both cell types adhered better to polymer films containing NHS coupled RGD peptide after 2 h even in the presence of albumin but significant cell detachment occurred after 4 days. Polymer solutions were electrospun into fibrous scaffolds. Both nonfouling and peptide binding characteristics were retained after processing. Copyright © 2012 Wiley Periodicals, Inc.

  1. Targeting Focal Adhesion Assembly by Ethoxyfagaronine Prevents Lymphoblastic Cell Adhesion to Fibronectin

    Directory of Open Access Journals (Sweden)

    F. Ouchani

    2012-01-01

    Full Text Available Background: Leukemic cell adhesion to proteins of the bone marrow microenvironment provides signals which control morphology, motility and cell survival. We described herein the ability of ethoxyfagaronine (etxfag, a soluble synthetic derivative of fagaronine, to prevent leukemic cell adhesion to fibronectin peptide (FN/V.

  2. Molecular mechanisms involved in TFF3 peptide-mediated modulation of the E-cadherin/catenin cell adhesion complex.

    Science.gov (United States)

    Meyer zum Büschenfelde, Dirk; Hoschützky, Heinz; Tauber, Rudolf; Huber, Otmar

    2004-05-01

    TFF3 is a member of the TFF-domain peptide family which is constitutively expressed in mucous epithelial tissues where it acts as a motogenic factor and plays an important role during epithelial restitution after wounding and during inflammation. In contrast to these beneficial functions, TFFs were also reported to be involved in cell scattering and tumor invasion. These changes in epithelial cell morphology and motility are associated with a modulation of cell contacts. In this respect, we here investigated the E-cadherin/catenin cell adhesion complex in FLAG-hTFF3-transfected HT29/B6 and MDCK cells. In hTFF3-transfected cells the amount of E-cadherin is reduced with a concomitant reduction of alpha- and beta-catenin levels. On one hand, E-cadherin expression is lowered at the transcriptional level as shown by multiplex RT-PCR analysis. This decrease does not depend on differences in the promoter methylation status as shown by methylation-specific PCR. On the other hand, pulse-chase experiments showed a reduction in the E-cadherin half-life in hTFF3-transfected cells reflecting increased E-cadherin degradation. In summary, hTFF3 induces transcriptional and posttranslational processes resulting in a modulation of E-cadherin-mediated cell-cell contacts that may play an important role in the paradoxical benefical and pathogenic function of TFF peptides.

  3. Identification of neural cell adhesion molecule L1-derived neuritogenic ligands of the fibroblast growth factor receptor

    DEFF Research Database (Denmark)

    Kulahin, Nikolaj; Li, Shizhong; Kiselyov, Vladislav

    2009-01-01

    The neural cell adhesion molecule L1 plays an important role in axon growth, neuronal survival, and synaptic plasticity. We recently demonstrated that the L1 fibronectin type III (FN3) modules interact directly with the fibroblast growth factor (FGF) receptor (FGFR). Sequence alignment of individ......The neural cell adhesion molecule L1 plays an important role in axon growth, neuronal survival, and synaptic plasticity. We recently demonstrated that the L1 fibronectin type III (FN3) modules interact directly with the fibroblast growth factor (FGF) receptor (FGFR). Sequence alignment...... of individual L1 FN3 modules with various FGFs suggested that four sequence motifs located in the third and fifth L1 FN3 modules might be involved in interactions with FGFR. The present study found that corresponding synthetic peptides, termed elcamins 1, 2, 3, and 4, bind and activate FGFR in the absence...... of FGF1. Conversely, in the presence of FGF1, elcamins inhibited receptor phosphorylation, indicating that the peptides are FGFR partial agonists. Elcamins 1, 3, and 4 dose dependently induced neurite outgrowth in cultured primary cerebellar neurons. The neuritogenic effect of elcamins was dependent...

  4. Functionalization of CoCr surfaces with cell adhesive peptides to promote HUVECs adhesion and proliferation

    Science.gov (United States)

    Castellanos, Maria Isabel; Mas-Moruno, Carlos; Grau, Anna; Serra-Picamal, Xavier; Trepat, Xavier; Albericio, Fernando; Joner, Michael; Gil, Francisco Javier; Ginebra, Maria Pau; Manero, Jose María; Pegueroles, Marta

    2017-01-01

    Biomimetic surface modification with peptides that have specific cell-binding moieties is a promising approach to improve endothelialization of metal-based stents. In this study, we functionalized CoCr surfaces with RGDS, REDV, YIGSR peptides and their combinations to promote endothelial cells (ECs) adhesion and proliferation. An extensive characterization of the functionalized surfaces was performed by XPS analysis, surface charge and quartz crystal microbalance with dissipation monitoring (QCM-D), which demonstrated the successful immobilization of the peptides to the surface. Cell studies demonstrated that the covalent functionalization of CoCr surfaces with an equimolar combination of RGDS and YIGSR represents the most powerful strategy to enhance the early stages of ECs adhesion and proliferation, indicating a positive synergistic effect between the two peptide motifs. Although these peptide sequences slightly increased smooth muscle cells (SMCs) adhesion, these values were ten times lower than those observed for ECs. The combination of RGDS with the REDV sequence did not show synergistic effects in promoting the adhesion or proliferation of ECs. The strategy presented in this study holds great potential to overcome clinical limitations of current metal stents by enhancing their capacity to support surface endothelialization.

  5. Release of membrane-bound vesicles and inhibition of tumor cell adhesion by the peptide Neopetrosiamide A.

    Directory of Open Access Journals (Sweden)

    Pamela Austin

    Full Text Available BACKGROUND: Neopetrosiamide A (NeoA is a 28-amino acid tricyclic peptide originally isolated from a marine sponge as a tumor cell invasion inhibitor whose mechanism of action is unknown. METHODOLOGY/PRINCIPAL FINDINGS: We show that NeoA reversibly inhibits tumor cell adhesion, disassembles focal adhesions in pre-attached cells, and decreases the level of beta1 integrin subunits on the cell surface. NeoA also induces the formation of dynamic, membrane-bound protrusions on the surface of treated cells and the release of membrane-bound vesicles into the culture medium. Proteomic analysis indicates that the vesicles contain EGF and transferrin receptors as well as a number of proteins involved in adhesion and migration including: beta1 integrin and numerous alpha integrin subunits; actin and actin-binding proteins such as cofilin, moesin and myosin 1C; and membrane modulating eps15 homology domain (EHD proteins. Surface labeling, trafficking inhibition, and real-time imaging experiments all suggest that beta1 integrin-containing vesicles are released directly from NeoA-induced cell surface protrusions rather than from vesicles generated intracellularly. The biological activity of NeoA is dependent on its disulfide bond pattern and NMR spectroscopy indicates that the peptide is globular with a continuous ridge of hydrophobic groups flanked by charged amino acid residues that could facilitate a simultaneous interaction with lipids and proteins in the membrane. CONCLUSIONS/SIGNIFICANCE: NeoA is an anti-adhesive peptide that decreases cell surface integrin levels through a novel, yet to be elucidated, mechanism that involves the release of adhesion molecule-containing vesicles from the cell surface.

  6. Immobilisation of linear and cyclic RGD-peptides on titanium surfaces and their impact on endothelial cell adhesion and proliferation

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    PW Kämmerer

    2011-04-01

    Full Text Available Functional coatings on titanium vascular stents and endosseous dental implants could probably enhance endothelial cell (EC adhesion and activity with a shortening of the wound healing time and an increase of peri-implant angiogenesis during early bone formation. Therefore, the role of the structure of linear and cyclic cell adhesive peptides Arg-Gly-Asp (l-RGD and c-RGD on differently pre-treated titanium (Ti surfaces (untreated, silanised vs. functionalised with l- and c-RGD peptides on EC cell coverage and proliferation was evaluated. After 24 h and after 3 d, surface coverage of adherent cells was quantified and an alamarBlue® proliferation assay was conducted. After 24 h, l-RGD modified surfaces showed a significantly better coverage of adhered cells than untreated titanium (p=0.01. Differences between l-RGD surfaces and silanised Ti (p=0.066 as well as between l-RGD and c-RGD surfaces (p=0.191 were not significant. After 3 d, c-RGD surfaces showed a significantly higher cell coverage than untreated Ti, silanised and l-RGD titanium surfaces (all p<0.0001. After 24 h, c-RGD modified surfaces showed significant higher cell proliferation compared to untreated Ti (p=0.003. However, there were no differences in proliferation between c-RGD and l-RGD (p=0.126 or c-RGD and silanised titanium (p=0.196. After 3 d, proliferation on c-RGD surfaces outranged significantly untreated titanium (p=0.004, silanised (p=0.001 and l-RGD surfaces (p=0.023, whereas no significant difference could be found between untreated Ti and l-RGD surfaces (p=0.54. According to these results, the biomimetic coating of c-RGD peptides on conventional titanium surfaces showed a positive effect on EC cell coverage and proliferation. We were able to show that modifications of titanium surfaces with c-RGD are a promising approach in promoting endothelial cell growth.

  7. Covalent attachment of cell-adhesive peptide Gly-Arg-Gly-Asp (GRGD) to poly(etheretherketone) surface by tailored silanization layers technique

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Yanyan [Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Xiong, Chengdong [Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041 (China); Li, Xiaoyu [State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041 (China); Zhang, Lifang, E-mail: zhanglfcioc@163.com [Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041 (China)

    2014-11-30

    Highlights: • The carbonyl groups on PEEK surface were effectively reduced to hydroxyl groups using sodium borohydride. • Silanization layers technique was employed to immobilize the cell-adhesive peptide Gly-Arg-Gly-Asp (GRGD) on hydroxylation-pretreated PEEK sheet surface by covalent chemical attachment. • XPS, surface profiler and water contact angle measurements proved the presence of GRGD on PEEK surface. • Osteoblast-like cells (MC3T3-E1) attachment and proliferation were improved effectively on GRGD-modified PEEK surface. - Abstract: Poly(etheretherketone) (PEEK) is a rigid semicrystalline polymer that combines excellent mechanical properties, broad chemical resistance and bone-like stiffness and is widely used in biomedical fields. However, PEEK is naturally bioinert, leading to limited biomedical applications, especially when a direct bone-implant osteointegration is desired. In this study, a three-step reaction procedure was employed to immobilize the cell-adhesive peptide Gly-Arg-Gly-Asp (GRGD) on the surface of PEEK sheet by covalent chemical attachment to favor cell adhesion and proliferation. First, hydroxylation-pretreated PEEK surfaces were silanized with 7-Oct-1-enyltrichlorosilane (OETS) in dry cyclohexane, resulting in a silanization layer with terminal ethenyl. Second, the terminal ethylenic double bonds of the silanization layer on PEEK surface were converted to carboxyl groups through acidic potassium manganate oxidation. Finally, GRGD was covalently attached by carbodiimide mediated condensation between the carboxyl on PEEK surface and amine presents in GRGD. X-ray photoelectron spectroscopy (XPS), attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, surface profiler and water contact angle measurements were applied to characterize the modified surfaces. The effect of cells attachment and proliferation on each specimen was investigated. Pre-osteoblast cells (MC3T3-E1) attachment, spreading and proliferation

  8. Covalent attachment of cell-adhesive peptide Gly-Arg-Gly-Asp (GRGD) to poly(etheretherketone) surface by tailored silanization layers technique

    Science.gov (United States)

    Zheng, Yanyan; Xiong, Chengdong; Li, Xiaoyu; Zhang, Lifang

    2014-11-01

    Poly(etheretherketone) (PEEK) is a rigid semicrystalline polymer that combines excellent mechanical properties, broad chemical resistance and bone-like stiffness and is widely used in biomedical fields. However, PEEK is naturally bioinert, leading to limited biomedical applications, especially when a direct bone-implant osteointegration is desired. In this study, a three-step reaction procedure was employed to immobilize the cell-adhesive peptide Gly-Arg-Gly-Asp (GRGD) on the surface of PEEK sheet by covalent chemical attachment to favor cell adhesion and proliferation. First, hydroxylation-pretreated PEEK surfaces were silanized with 7-Oct-1-enyltrichlorosilane (OETS) in dry cyclohexane, resulting in a silanization layer with terminal ethenyl. Second, the terminal ethylenic double bonds of the silanization layer on PEEK surface were converted to carboxyl groups through acidic potassium manganate oxidation. Finally, GRGD was covalently attached by carbodiimide mediated condensation between the carboxyl on PEEK surface and amine presents in GRGD. X-ray photoelectron spectroscopy (XPS), attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, surface profiler and water contact angle measurements were applied to characterize the modified surfaces. The effect of cells attachment and proliferation on each specimen was investigated. Pre-osteoblast cells (MC3T3-E1) attachment, spreading and proliferation were improved effectively on GRGD-modified PEEK surface. PEEK modified with GRGD on its surface has potential use in orthopedic or dental implants.

  9. NCAM-mimetic, FGL peptide, restores disrupted fibroblast growth factor receptor (FGFR) phosphorylation and FGFR mediated signaling in neural cell adhesion molecule (NCAM)-deficient mice

    DEFF Research Database (Denmark)

    Aonurm-Helm, Anu; Berezin, Vladimir; Bock, Elisabeth;

    2010-01-01

    Neural cell adhesion molecule (NCAM) is a membrane-bound glycoprotein expressed on the surface of neuronal and glial cells. Previous in vitro studies have demonstrated that NCAM promotes neuronal functions largely via three main interaction partners: the fibroblast growth factor receptor (FGFR...... compared the levels of phosphorylation of FGFR1, Src kinase Fyn, Raf1 kinase, MAP kinases, Akt kinase and calcium/calmodulin-dependent kinases II and IV (CaMKII and CaMKIV) in the hippocampus of NCAM knockout mice to their wild-type littermates. The data of our study show that mice constitutively deficient...... in all isoforms of NCAM have decreased basal phosphorylation levels of FGFR1 and CaMKII and CaMKIV. Furthermore, NCAM-mimetic, FGL peptide, is found to be able to restore FGFR1, CaMKII and CaMKIV phosphorylation levels and thereby mimic the interactions of NCAM at this receptor in NCAM deficient mice...

  10. Cell-Adhesive Matrices Composed of RGD Peptide-Displaying M13 Bacteriophage/Poly(lactic-co-glycolic acid) Nanofibers Beneficial to Myoblast Differentiation.

    Science.gov (United States)

    Shin, Yong Cheol; Lee, Jong Ho; Jin, Linhua; Kim, Min Jeong; Kim, Chuntae; Hong, Suck Won; Oh, Jin Woo; Han, Dong-Wook

    2015-10-01

    Recently, there has been considerable effort to develop suitable scaffolds for tissue engineering applications. Cell adhesion is a prerequisite for cells to survive. In nature, the extracellular matrix (ECM) plays this role. Therefore, an ideal scaffold should be structurally similar to the natural ECM and have biocompatibility and biodegradability. In addition, the scaffold should have biofunctionality, which provides the potent ability to enhance the cellular behaviors, such as adhesion, proliferation and differentiation. This study concentrates on fabricating cell-adhesive matrices composed of RGD peptide-displaying M13 bacteriophage (RGD-M13 phage) and poly(lactic-co-glycolic acid, PLGA) nanofibers. Long rod-shaped M13 bacteriophages are non-toxic and can express many desired proteins on their surface. A genetically engineered M13 phage was constructed to display RGD peptides on its surface. PLGA is a biodegradable polymer with excellent biocompatibility and suitable physicochemical property for adhesive matrices. In this study, RGD-M13 phage/PLGA hybrid nanofiber matrices were fabricated by electrospinning. The physicochemical properties of these matrices were characterized by scanning electron microscopy, atomic force microscopy, Raman spectroscopy, and contact angle measurement. In addition, the cellular behaviors, such as the initial attachment, proliferation and differentiation, were analyzed by a CCK-8 assay and immunofluorescence staining to evaluate the potential application of these matrices to tissue engineering scaffolds. The RGD-M13 phage/PLGA nanofiber matrices could enhance the cellular behaviors and promote the differentiation of C2C12 myoblasts. These results suggest that the RGD-M13 phage/PLGA nanofiber matrices are beneficial to myoblast differentiation and can serve as effective tissue engineering scaffolds.

  11. Cognitive disorder and changes in cholinergic receptors, N-methyl-D aspartate receptors, neural cell adhesion molecule, and brain-derived neurotrophic factor following brain injury

    Institute of Scientific and Technical Information of China (English)

    Weiliang Zhao; Dezhi Kang; Yuanxiang Lin

    2008-01-01

    BACKGROUND: Learning and memory damage is one of the most permanent and the severest symptoms of traumatic brain injury; it can seriously influence the normal life and work of patients. Some research has demonstrated that cognitive disorder is closely related to nicotine cholinergic receptors, N-methyl-D aspartate receptors, neural cell adhesion molecule, and brain-derived neurotrophic factor. OBJECTIVE: To summarize the cognitive disorder and changes in nicotine cholinergic receptors, N-methyl-D aspartate receptors, neural cell adhesion molecule, and brain-derived neurotrophic factor following brain injury. RETRIEVAL STRATEGY: A computer-based online search was conducted in PUBMED for English language publications containing the key words "brain injured, cognitive handicap, acetylcholine, N-methyl-D aspartate receptors, neural cell adhesion molecule, brain-derived neurotrophic factor" from January 2000 to December 2007. There were 44 papers in total. Inclusion criteria: ① articles about changes in nicotine cholinergic receptors, N-methyl-D aspartate receptors, neural cell adhesion molecule, and brain-derived neurotrophic factor following brain injury; ② articles in the same researching circle published in authoritative journals or recently published. Exclusion criteria: duplicated articles.LITERATURE EVALUATION: References were mainly derived from research on changes in these four factors following brain injury. The 20 included papers were clinical or basic experimental studies. DATA SYNTHESIS: After craniocerebral injury, changes in these four factors in brain were similar to those during recovery from cognitive disorder, to a certain degree. Some data have indicated that activation of nicotine cholinergic receptors, N-methyl-D aspartate receptors, neural cell adhesion molecule, and brain-derived neurotrophic factor could greatly improve cognitive disorder following brain injury. However, there are still a lot of questions remaining; for example, how do these

  12. Alcalase-catalysed synthesis of the precursor tetrapeptide N-benzoylarginylglycylaspartylserinamide (Bz-RGDS-NH2) of the cell-adhesion peptide arginylglycylaspartylserine (RGDS).

    Science.gov (United States)

    Huang, Yi-Bing; Yang, Sen; Cai, Yu; Wang, Hua; Gao, Gui; Wu, Xiao-Xia; Xu, Li; Zhang, Xue-Zhong

    2008-11-01

    In the present study, a precursor tetrapeptide Bz-RGDS-NH2 (N-benzoylarginylglycylaspartylserinamide) of cell-adhesion peptide RGDS (arginylglycylaspartylserine) was synthesized by a novel route. First of all, the precursor tripeptide GDS-NH2 (glycylaspartylserinamide) was synthesized by a chemical method only using aspartic acid and serine at gram scale in four steps. The linkage of the fourth amino acid Bz-Arg-OEt (N-benzoyl-L-arginine ethyl ester) to GDS-NH2 was completed by an enzymatic method under kinetic control in water-miscible organic media. An industrial alkaline protease, Alcalase, with a wide substrate specificity, was used as the catalyst. The effects of organic solvents, pH value, reaction temperature, water content and molar ratio of substrates on the yield of Bz-RGDS-NH2 synthesis were examined. The optimum reaction conditions were found to be pH 10.0, 35 degrees C, 8 h, in an acetonitrile/(Na2CO3/NaHCO3) buffer system (93:7, v/v) with a maximal yield of 65.2%. We found that secondary hydrolysis of the peptide product did not take place in these water-miscible organic solvents.

  13. Cell Adhesion Induced Using Surface Modification with Cell-Penetrating Peptide-Conjugated Poly(ethylene glycol)-Lipid: A New Cell Glue for 3D Cell-Based Structures.

    Science.gov (United States)

    Teramura, Yuji; Asif, Sana; Ekdahl, Kristina N; Gustafson, Elisabet; Nilsson, Bo

    2017-01-11

    We synthesized a novel material, cell-penetrating peptide-conjugated poly(ethylene glycol)-lipid (CPP-PEG-lipid), that can induce the adhesion of floating cells. Firm cell adhesion with spreading could be induced by cell surface modification with the CPP-PEG-lipids. Cell adhesion was induced by CPPs but not by any other cationic short peptides we tested. Here, we demonstrated adherence using the floating cell line CCRF-CEM as well as primary human T cells, B cells, erythrocytes, and hepatocytes. As compared to cells grown in suspension, adherent cells were more rapidly induced to attach to substrates with the cell-surface modification. The critical factor for attachment was localization of CPPs at the cell membrane by PEG-lipids with PEG > 20 kDa. These cationic CPPs on PEG chains were able to interact with substrate surfaces such as polystyrene (PS) surfaces, glass surfaces, and PS microfibers that are negatively charged, inducing firm cell adhesion and cell spreading. Also, as opposed to normal cationic peptides that interact strongly with cell membranes, CPPs were less interactive with the cell surfaces because of their cell-penetrating property, making them more available for adhering cells to the substrate surface. No effects on cell viability or cell proliferation were observed after the induction of cell adhesion. With this technique, cells could be easily immobilized onto PS microfibers, an important step in fabricating 3D cell-based structures. Cells immobilized onto 3D PS microfibers were alive, and human hepatocytes showed normal production of urea and albumin on the microfibers. This method is novel in inducing firm cell adhesion via a one-step treatment.

  14. RGD peptide-displaying M13 bacteriophage/PLGA nanofibers as cell-adhesive matrices for smooth muscle cells

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Yong Cheol; Lee, Jong Ho; Jin, Oh Seong; Lee, Eun Ji; Jin, Lin Hua; Kim, Chang Seok; Hong, Suck Won; Han, Dong Wook; Kim, Chun Tae; Oh, Jin Woo [Pusan National University, Busan (Korea, Republic of)

    2015-01-15

    Extracellular matrices (ECMs) are network structures that play an essential role in regulating cellular growth and differentiation. In this study, novel nanofibrous matrices were fabricated by electrospinning M13 bacteriophage and poly(lactic-co-glycolic acid) (PLGA) and were shown to be structurally and functionally similar to natural ECMs. A genetically-engineered M13 bacteriophage was constructed to display Arg-Gly-Asp (RGD) peptides on its surface. The physicochemical properties of RGD peptide-displaying M13 bacteriophage (RGD-M13 phage)/PLGA nanofibers were characterized by using scanning electron microscopy and Fourier-transform infrared spectroscopy. We used immunofluorescence staining to confirm that M13 bacteriophages were homogenously distributed in RGD-M13 phage/PLGA matrices. Furthermore, RGD-M13 phage/PLGA nanofibrous matrices, having excellent biocompatibility, can enhance the behaviors of vascular smooth muscle cells. This result suggests that RGD-M13 phage/PLGA nanofibrous matrices have potentials to serve as tissue engineering scaffolds.

  15. Cell-adhesive RGD peptide-displaying M13 bacteriophage/PLGA nanofiber matrices for growth of fibroblasts.

    Science.gov (United States)

    Shin, Yong Cheol; Lee, Jong Ho; Jin, Linhua; Kim, Min Jeong; Oh, Jin-Woo; Kim, Tai Wan; Han, Dong-Wook

    2014-01-01

    M13 bacteriophages can be readily fabricated as nanofibers due to non-toxic bacterial virus with a nanofiber-like shape. In the present study, we prepared hybrid nanofiber matrices composed of poly(lactic-co-glycolic acid, PLGA) and M13 bacteriophages which were genetically modified to display the RGD peptide on their surface (RGD-M13 phage). The surface morphology and chemical composition of hybrid nanofiber matrices were characterized by scanning electron microscopy (SEM) and Raman spectroscopy, respectively. Immunofluorescence staining was conducted to investigate the existence of M13 bacteriophages in RGD-M13 phage/PLGA hybrid nanofibers. In addition, the attachment and proliferation of three different types of fibroblasts on RGD-M13 phage/PLGA nanofiber matrices were evaluated to explore how fibroblasts interact with these matrices. SEM images showed that RGD-M13 phage/PLGA hybrid matrices had the non-woven porous structure, quite similar to that of natural extracellular matrices, having an average fiber diameter of about 190 nm. Immunofluorescence images and Raman spectra revealed that RGD-M13 phages were homogeneously distributed in entire matrices. Moreover, the attachment and proliferation of fibroblasts cultured on RGD-M13 phage/PLGA matrices were significantly enhanced due to enriched RGD moieties on hybrid matrices. These results suggest that RGD-M13 phage/PLGA matrices can be efficiently used as biomimetic scaffolds for tissue engineering applications.

  16. Polysialic acid modification of the synaptic cell adhesion molecule SynCAM 1 in human embryonic stem cell-derived oligodendrocyte precursor cells

    Directory of Open Access Journals (Sweden)

    Sebastian Werneburg

    2015-05-01

    Full Text Available Oligodendrocyte precursor cells (OPCs are the progenitors of myelinating oligodendrocytes in brain development and repair. Successful myelination depends on the control of adhesiveness during OPC migration and axon contact formation. The decoration of cell surface proteins with the glycan polysialic acid (polySia is a key regulatory element of OPC interactions during development and under pathological conditions. By far the major protein carrier of polySia is the neural cell adhesion molecule NCAM, but recently, polysialylation of the synaptic cell adhesion molecule SynCAM 1 has been detected in the developing mouse brain. In mice, polySia-SynCAM 1 is associated with cells expressing NG2, a marker of a heterogeneous precursor cell population, which is the primary source for oligodendrocytes in development and myelin repair but can also give rise to astrocytes and possibly neurons. It is not yet clear if polySia-SynCAM 1 is expressed by OPCs and its occurrence in humans is elusive. By generating uniform human embryonic stem cell-derived OPC cultures, we demonstrate that polySia is present on human OPCs but down-regulated during differentiation into myelin basic protein-positive oligodendrocytes. PolySia on NCAM resides on the isoforms NCAM-180 and NCAM-140, and SynCAM 1 is identified as a novel polySia acceptor in human OPCs.

  17. Cell adhesion and sorting in embryoid bodies derived from N- or E-cadherin deficient murine embryonic stem cells

    Directory of Open Access Journals (Sweden)

    Robert Moore

    2014-01-01

    The primitive endoderm epithelial structure in mouse blastocysts forms following cell differentiation and subsequent sorting, and this two-step process can be reproduced in vitro using an embryoid body model. We found that in the chimeric embryoid bodies consisting of paired wildtype and E-cadherin null ES cells, the wildtype sorted to the center and were enveloped by the less adhesive E-cadherin null cells, in accord with Steinberg's hypothesis. However, wildtype and N-cadherin null ES cells intermixed and did not segregate, a situation that may be explained by Albert Harris' modified principle, which incorporates the unique properties of living cells. Furthermore, in chimeric embryoid bodies composed of N-cadherin and E-cadherin null ES cells, the two weakly interacting cell types segregated but did not envelop one another. Lastly, the most consistent and striking observation was that differentiated cells sorted to the surface and formed an enveloping layer, regardless of the relative cell adhesive affinity of any cell combination, supporting the hypothesis that the ability of the differentiated cells to establish apical polarity is the determining factor in surface sorting and positioning.

  18. A peptide motif from the second fibronectin module of the neural cell adhesion molecule, NCAM, NLIKQDDGGSPIRHY, is a binding site for the FGF receptor

    DEFF Research Database (Denmark)

    Jacobsen, Jacob Hedemand; Kiselyov, Vladislav; Bock, Elisabeth

    2008-01-01

    The mechanism of fibroblast growth factor receptor (FGFR) activation by the neural cell adhesion molecule (NCAM) is not well understood. A motif in the second NCAM fibronectin type III (FN3) module, termed FGL, has by means of nuclear magnetic resonance (NMR) and surface plasmon resonance (SPR) a...

  19. Influence of E-cadherin-mediated cell adhesion on mouse embryonic stem cells derivation from isolated blastomeres.

    Science.gov (United States)

    González, Sheyla; Ibáñez, Elena; Santaló, Josep

    2011-09-01

    Efforts to efficiently derive embryonic stem cells (ESC) from isolated blastomeres have been done to minimize ethical concerns about human embryo destruction. Previous studies in our laboratory indicated a poor derivation efficiency of mouse ESC lines from isolated blastomeres at the 8-cell stage (1/8 blastomeres) due, in part, to a low division rate of the single blastomeres in comparison to their counterparts with a higher number of blastomeres (2/8, 3/8 and 4/8 blastomeres). Communication and adhesion between blastomeres from which the derivation process begins could be important aspects to efficiently derive ESC lines. In the present study, an approach consisting in the adhesion of a chimeric E-cadherin (E-cad-Fc) to the blastomere surface was devised to recreate the signaling produced by native E-cadherin between neighboring blastomeres inside the embryo. By this approach, the division rate of 1/8 blastomeres increased from 44.6% to 88.8% and a short exposure of 24 h to the E-cad-Fc produced an ESC derivation efficiency of 33.6%, significantly higher than the 2.2% obtained from the control group without E-cad-Fc. By contrast, a longer exposure to the same chimeric protein resulted in higher proportions of trophoblastic vesicles. Thus, we establish an important role of E-cadherin-mediated adherens junctions in promoting both the division of single 1/8 blastomeres and the efficiency of the ESC derivation process.

  20. Syndecans and cell adhesion

    DEFF Research Database (Denmark)

    Couchman, J R; Chen, L; Woods, A

    2001-01-01

    Now that transmembrane signaling through primary cell-matrix receptors, integrins, is being elucidated, attention is turning to how integrin-ligand interactions can be modulated. Syndecans are transmembrane proteoglycans implicated as coreceptors in a variety of physiological processes, including...... cell adhesion, migration, response to growth factors, development, and tumorigenesis. This review will describe this family of proteoglycans in terms of their structures and functions and their signaling in conjunction with integrins, and indicate areas for future research....

  1. Screening of integrin-binding peptides in a laminin peptide library derived from the mouse laminin β chain short arm regions.

    Science.gov (United States)

    Katagiri, Fumihiko; Takagi, Masaharu; Nakamura, Minako; Tanaka, Yoichiro; Hozumi, Kentaro; Kikkawa, Yamato; Nomizu, Motoyoshi

    2014-05-15

    Laminins, major components of basement membrane, consist of three different subunits, α, β, and γ chains, and so far, five α, three β, and three γ chains have been identified. We have constructed synthetic peptide libraries derived from the laminin sequences and identified various cell-adhesive peptides. Ten active peptides from the laminin α chain sequences (α1-α5) were found to promote integrin-mediated cell adhesion. Previously, we found fourteen cell-adhesive peptides from the β1 chain sequence but their receptors have not been analyzed. Here, we expanded the synthetic peptide library to add peptides from the short arm regions of the laminin β2 and β3 chains and screened for integrin-binding peptides. Twenty-seven peptides promoted human dermal fibroblast (HDF) attachment in a peptide-coated plate assay. The morphological appearance of HDFs on the peptide-coated plates differed depending on the peptides. B34 (REKYYYAVYDMV, mouse laminin β1 chain, 255-266), B67 (IPYSMEYEILIRY, mouse laminin β1 chain, 604-616), B2-105 (APNFWNFTSGRG, mouse laminin β2 chain, 1081-1092), and B3-19 (GHLTGGKVQLNL, mouse laminin β3 chain, 182-193) promoted HDF spreading and HDF attachment was inhibited by EDTA, suggesting that the peptides interact with integrins. Immunostaining analyses revealed that B67 induced well-organized actin stress fibers and focal contacts containing vinculin, however, B34, B2-105, and B3-19 did not exhibit stress fiber formation or focal contacts. The inhibition assay using anti-integrin antibodies indicated that B67 interacts with α3, α6, and β1 integrins, and B34 and B3-19 interact with β1 integrin. Based on adhesion analysis of peptides modified with an alanine scan and on switching analysis with the homologous inactive sequence B2-64 (LPRAMDYDLLLRW, mouse laminin β2 chain, 618-630), the Glu(8) residue in the B67 peptide was critical for HDF adhesion. These findings are useful for identifying an integrin binding motif. The B67 peptide

  2. Overexpression of Polysialylated Neural Cell Adhesion Molecule Improves the Migration Capacity of Induced Pluripotent Stem Cell-Derived Oligodendrocyte Precursors

    NARCIS (Netherlands)

    Czepiel, Marcin; Leicher, Lasse; Becker, Katja; Boddeke, Erik; Copray, Sjef

    2014-01-01

    Cell replacement therapy aiming at the compensation of lost oligodendrocytes and restoration of myelination in acquired or congenital demyelination disorders has gained considerable interest since the discovery of induced pluripotent stem cells (iPSCs). Patient-derived iPSCs provide an inexhaustible

  3. Glial cell line-derived neurotrophic factor (GDNF) induces neuritogenesis in the cochlear spiral ganglion via neural cell adhesion molecule (NCAM).

    Science.gov (United States)

    Euteneuer, Sara; Yang, Kuo H; Chavez, Eduardo; Leichtle, Anke; Loers, Gabriele; Olshansky, Adel; Pak, Kwang; Schachner, Melitta; Ryan, Allen F

    2013-05-01

    Glial cell line-derived neurotrophic factor (GDNF) increases survival and neurite extension of spiral ganglion neurons (SGNs), the primary neurons of the auditory system, via yet unknown signaling mechanisms. In other cell types, signaling is achieved by the GPI-linked GDNF family receptor α1 (GFRα1) via recruitment of transmembrane receptors: Ret (re-arranged during transformation) and/or NCAM (neural cell adhesion molecule). Here we show that GDNF enhances neuritogenesis in organotypic cultures of spiral ganglia from 5-day-old rats and mice. Addition of GFRα1-Fc increases this effect. GDNF/GFRα1-Fc stimulation activates intracellular PI3K/Akt and MEK/Erk signaling cascades as detected by Western blot analysis of cultures prepared from rats at postnatal days 5 (P5, before the onset of hearing) and 20 (P20, after the onset of hearing). Both cascades mediate GDNF stimulation of neuritogenesis, since application of the Akt inhibitor Wortmannin or the Erk inhibitor U0126 abolished GDNF/GFRα1-Fc stimulated neuritogenesis in P5 rats. Since cultures of P5 NCAM-deficient mice failed to respond by neuritogenesis to GDNF/GFRα1-Fc, we conclude that NCAM serves as a receptor for GDNF signaling responsible for neuritogenesis in early postnatal spiral ganglion.

  4. Modulation of Sickle Red Blood Cell Adhesion and its Associated Changes in Biomarkers by Sulfated Nonanticoagulant Heparin Derivative.

    Science.gov (United States)

    Alshaiban, Abdulelah; Muralidharan-Chari, Vandhana; Nepo, Anne; Mousa, Shaker A

    2016-04-01

    Abnormal cellular adhesion is one of the primary causes of vaso-occlusive crisis in sickle cell disease (SCD). Levels of intercellular adhesion molecule 1 (ICAM-1) and P-selectin are upregulated, resulting in increased adhesion of leukocytes and sickle red blood cells (RBCs) to endothelium. This study compares the inhibitory effect of a sulfated nonanticoagulant heparin (S-NACH) derivative with a low-molecular-weight heparin, tinzaparin, on the adhesion of sickle RBCs to endothelium. The S-NACH exhibits minimum effects on hemostasis and bleeding and interferes with the binding of pancreatic cancer cells to endothelial cells via P-selectin. We show by static binding assay that pretreatment of both erythrocytes and endothelial cells with S-NACH significantly inhibits the increased adhesion of sickle RBCs to endothelial cells. The S-NACH treatment also decreases the higher plasma levels of (adhesion biomarkers) ICAM-1 and P-selectin in SCD mice. This investigation signals further research into the potential use of S-NACH in treating vaso-occlusions with minimal bleeding events in patients with SCD.

  5. [Endothelial cell adhesion molecules].

    Science.gov (United States)

    Ivanov, A N; Norkin, I A; Puchin'ian, D M; Shirokov, V Iu; Zhdanova, O Iu

    2014-01-01

    The review presents current data concerning the functional role of endothelial cell adhesion molecules belonging to different structural families: integrins, selectins, cadherins, and the immunoglobulin super-family. In this manuscript the regulatory mechanisms and factors of adhesion molecules expression and distribution on the surface of endothelial cells are discussed. The data presented reveal the importance of adhesion molecules in the regulation of structural and functional state of endothelial cells in normal conditions and in pathology. Particular attention is paid to the importance of these molecules in the processes of physiological and pathological angiogenesis, regulation of permeability of the endothelial barrier and cell transmigration.

  6. The neural cell adhesion molecule

    DEFF Research Database (Denmark)

    Berezin, V; Bock, E; Poulsen, F M

    2000-01-01

    During the past year, the understanding of the structure and function of neural cell adhesion has advanced considerably. The three-dimensional structures of several of the individual modules of the neural cell adhesion molecule (NCAM) have been determined, as well as the structure of the complex...... between two identical fragments of the NCAM. Also during the past year, a link between homophilic cell adhesion and several signal transduction pathways has been proposed, connecting the event of cell surface adhesion to cellular responses such as neurite outgrowth. Finally, the stimulation of neurite...

  7. RGD modified polymers: biomaterials for stimulated cell adhesion and beyond.

    Science.gov (United States)

    Hersel, Ulrich; Dahmen, Claudia; Kessler, Horst

    2003-11-01

    Since RGD peptides (R: arginine; G: glycine; D: aspartic acid) have been found to promote cell adhesion in 1984 (Cell attachment activity of fibronectin can be duplicated by small synthetic fragments of the molecule, Nature 309 (1984) 30), numerous materials have been RGD functionalized for academic studies or medical applications. This review gives an overview of RGD modified polymers, that have been used for cell adhesion, and provides information about technical aspects of RGD immobilization on polymers. The impacts of RGD peptide surface density, spatial arrangement as well as integrin affinity and selectivity on cell responses like adhesion and migration are discussed.

  8. Role of glial cell line-derived neurotrophic factor (GDNF)-neural cell adhesion molecule (NCAM) interactions in induction of neurite outgrowth and identification of a binding site for NCAM in the heel region of GDNF

    DEFF Research Database (Denmark)

    Nielsen, Janne; Gotfryd, Kamil; Li, Shizhong

    2009-01-01

    The formation of appropriate neuronal circuits is an essential part of nervous system development and relies heavily on the outgrowth of axons and dendrites and their guidance to their respective targets. This process is governed by a large array of molecules, including glial cell line......-derived neurotrophic factor (GDNF) and the neural cell adhesion molecule (NCAM), the interaction of which induce neurite outgrowth. In the present study the requirements for NCAM-mediated GDNF-induced neurite outgrowth were investigated in cultures of hippocampal neurons, which do not express Ret. We demonstrate...

  9. Repetitive Gly-Leu-Lys-Gly-Glu-Asn-Arg-Gly-Asp peptide derived from collagen and fibronectin for improving cell-scaffold interaction.

    Science.gov (United States)

    Chaisri, Patcharaporn; Chingsungnoen, Artit; Siri, Sineenat

    2015-03-01

    Suitable scaffolds for tissue engineering should provide a microenvironment for cell dwelling and directing cell behavior that resemble the native environment. Three-dimensional geometry of electrospun scaffolds well supports cell deposition, but they often lack biomacromolecules to induce cell responses. In this work, the repetitive collagen and fibronectin motif (rCF) peptide containing multiple repeats of Gly-Leu-Lys-Gly-Glu-Asn-Arg-Gly-Asp sequence derived from the cell adhesion motifs of collagen and fibronectin was produced as the alternative agent to induce cell-scaffold interaction. The DNA fragment encoding rCF peptide was amplified by a polymerase chain reaction using overlap primers without a DNA template, cloned into a protein expression vector, and expressed as a His-tag fusion peptide in Escherichia coli. The purified rCF peptide possessed cell adhesion activity about 1.5-fold of the commercial RGD peptide. The rCF peptide was grafted onto the electrospun PCL scaffold via RF plasma of Ar/O2 discharge and acrylic acid treatment. The immobilized rCF peptide significantly increased surface hydrophilicity and enhanced cell proliferation of the electrospun PCL scaffold. These findings suggest the potential application of rCF peptide for improving the biomimetic functions of polymeric scaffolds for tissue engineering.

  10. Indirect coating of RGD peptides using a poly-L-lysine spacer enhances jaw periosteal cell adhesion, proliferation, and differentiation into osteogenic tissue.

    Science.gov (United States)

    Ardjomandi, N; Klein, C; Kohler, K; Maurer, A; Kalbacher, H; Niederländer, J; Reinert, S; Alexander, D

    2012-08-01

    The aim of our study was to generate a biofunctionalized, three-dimensional (3D) biomaterial to enhance jaw periosteal cell (JPC) adhesion and differentiation into osteogenic tissue. Therefore, open-cell polylactic acid (OPLA) scaffolds were coated covalently with different RGD peptides (a conserved recognition sequence of the most ECM proteins--arginine-glycine-asparagine) and different coating variants. The linear and cyclic RGD peptides were either applied directly or indirectly via a poly-L-lysine (PLL) spacer. JPCs were analyzed on coated constructs in 2D and 3D cultures and showed enhanced rates for indirectly coated scaffolds using the PLL spacer. By gene expression, we detected significantly increased levels of osteogenic marker genes, such as alkaline phosphatase, RUNX2, and AMELY in JPCs seeded onto PLL/linear RGD constructs compared to the otherwise-coated constructs. An analysis of the JPC mineralization capacity revealed the highest amounts of calcium-phosphate precipitates in cells growing within the PLL/linear scaffolds. Additionally, the JPC adhesion behavior on OPLA scaffolds seems to be mediated by ITGB3, ITGB1, and ITGAV, as shown by blocking assays. We concluded that coating of OPLA constructs with linear RGD peptides via PLL represents a suitable approach for functionalizing the polymer surface and enhancing adhesion, proliferation, and mineralization of JPCs.

  11. Triggering cell adhesion, migration or shape change with a dynamic surface coating.

    Science.gov (United States)

    van Dongen, Stijn F M; Maiuri, Paolo; Marie, Emmanuelle; Tribet, Christophe; Piel, Matthieu

    2013-03-25

    There's an APP for that: cell-repellent APP (azido-[polylysine-g-PEG]) is used to create substrates for spatially controlled dynamic cell adhesion. The simple addition of a functional peptide to the culture medium rapidly triggers cell adhesion. This highly accessible yet powerful technique allows diverse applications, demonstrated through tissue motility assays, patterned coculturing and triggered cell shape change.

  12. A novel anti-inflammatory role of NCAM-derived mimetic peptide, FGL

    DEFF Research Database (Denmark)

    Downer, Eric J; Cowley, Thelma R; Lyons, Anthony;

    2010-01-01

    as a novel anti-inflammatory agent. Administration of FGL to aged rats attenuated the increased expression of markers of activated microglia, the increase in pro-inflammatory interleukin-1beta (IL-1beta) and the impairment in long-term potentiation (LTP). We report that the age-related increase in microglial......Age-related cognitive deficits in hippocampus are correlated with neuroinflammatory changes, typified by increased pro-inflammatory cytokine production and microglial activation. We provide evidence that the neural cell adhesion molecule (NCAM)-derived mimetic peptide, FG loop (FGL), acts...... CD200 in vitro. We provide evidence that the increase in CD200 is reliant on IL-4-induced extracellular signal-regulated kinase (ERK) signal transduction. These findings provide the first evidence of a role for FGL as an anti-inflammatory agent and identify a mechanism by which FGL controls...

  13. Inflammatory peptides derived from adipose tissue

    Directory of Open Access Journals (Sweden)

    Barzilai Nir

    2005-01-01

    Full Text Available Abstract The low-grade inflammation seen with aging is noted particularly in subjects with the metabolic syndrome of aging. Insulin resistance, obesity/abdominal obesity, and risks for many age-related diseases characterize this common syndrome. It is becoming clear that this increased adipose tissue is not simply a reservoir for excess nutrients, but rather an active and dynamic organ capable of expressing several cytokines and other fat-derived peptides (FDP. Some, but not all, FDP may have a role in development of the metabolic syndrome but there is no evidence that these FDP are causing inflammation directly. We suggest that high levels of inflammatory peptides are markers for obesity/abdominal obesity seen with aging, but some may not necessarily have a causative role in the development of inflammation.

  14. Discoidin domain receptors promote α1β1- and α2β1-integrin mediated cell adhesion to collagen by enhancing integrin activation.

    Directory of Open Access Journals (Sweden)

    Huifang Xu

    Full Text Available The discoidin domain receptors, DDR1 and DDR2, are receptor tyrosine kinases that bind to and are activated by collagens. Similar to collagen-binding β1 integrins, the DDRs bind to specific motifs within the collagen triple helix. However, these two types of collagen receptors recognize distinct collagen sequences. While GVMGFO (O is hydroxyproline functions as a major DDR binding motif in fibrillar collagens, integrins bind to sequences containing Gxx'GEx". The DDRs are thought to regulate cell adhesion, but their roles have hitherto only been studied indirectly. In this study we used synthetic triple-helical collagen-derived peptides that incorporate either the DDR-selective GVMGFO motif or integrin-selective motifs, such as GxOGER and GLOGEN, in order to selectively target either type of receptor and resolve their contributions to cell adhesion. Our data using HEK293 cells show that while cell adhesion to collagen I was completely inhibited by anti-integrin blocking antibodies, the DDRs could mediate cell attachment to the GVMGFO motif in an integrin-independent manner. Cell binding to GVMGFO was independent of DDR receptor signalling and occurred with limited cell spreading, indicating that the DDRs do not mediate firm adhesion. However, blocking the interaction of DDR-expressing cells with collagen I via the GVMGFO site diminished cell adhesion, suggesting that the DDRs positively modulate integrin-mediated cell adhesion. Indeed, overexpression of the DDRs or activation of the DDRs by the GVMGFO ligand promoted α1β1 and α2β1 integrin-mediated cell adhesion to medium- and low-affinity integrin ligands without regulating the cell surface expression levels of α1β1 or α2β1. Our data thus demonstrate an adhesion-promoting role of the DDRs, whereby overexpression and/or activation of the DDRs leads to enhanced integrin-mediated cell adhesion as a result of higher integrin activation state.

  15. 'Special K' and a Loss of Cell-To-Cell Adhesion in Proximal Tubule-Derived Epithelial Cells: Modulation of the Adherens Junction Complex by Ketamine

    Science.gov (United States)

    Hills, Claire E.; Jin, Tianrong; Siamantouras, Eleftherios; Liu, Issac K-K; Jefferson, Kieran P.; Squires, Paul E.

    2013-01-01

    Ketamine, a mild hallucinogenic class C drug, is the fastest growing ‘party drug’ used by 16–24 year olds in the UK. As the recreational use of Ketamine increases we are beginning to see the signs of major renal and bladder complications. To date however, we know nothing of a role for Ketamine in modulating both structure and function of the human renal proximal tubule. In the current study we have used an established model cell line for human epithelial cells of the proximal tubule (HK2) to demonstrate that Ketamine evokes early changes in expression of proteins central to the adherens junction complex. Furthermore we use AFM single-cell force spectroscopy to assess if these changes functionally uncouple cells of the proximal tubule ahead of any overt loss in epithelial cell function. Our data suggests that Ketamine (24–48 hrs) produces gross changes in cell morphology and cytoskeletal architecture towards a fibrotic phenotype. These physical changes matched the concentration-dependent (0.1–1 mg/mL) cytotoxic effect of Ketamine and reflect a loss in expression of the key adherens junction proteins epithelial (E)- and neural (N)-cadherin and β-catenin. Down-regulation of protein expression does not involve the pro-fibrotic cytokine TGFβ, nor is it regulated by the usual increase in expression of Slug or Snail, the transcriptional regulators for E-cadherin. However, the loss in E-cadherin can be partially rescued pharmacologically by blocking p38 MAPK using SB203580. These data provide compelling evidence that Ketamine alters epithelial cell-to-cell adhesion and cell-coupling in the proximal kidney via a non-classical pro-fibrotic mechanism and the data provides the first indication that this illicit substance can have major implications on renal function. Understanding Ketamine-induced renal pathology may identify targets for future therapeutic intervention. PMID:24009666

  16. Syndecans, signaling, and cell adhesion

    DEFF Research Database (Denmark)

    Couchman, J R; Woods, A

    1996-01-01

    Syndecans are transmembrane proteoglycans which can participate in diverse cell surface interactions, involving extracellular matrix macromolecules, growth factors, protease inhibitors, and even viral entry. Currently, all extracellular interactions are believed to be mediated by distinct...... structures within the heparan sulfate chains, leaving the roles of chondroitin sulfate chains and extracellular portion of the core proteins to be elucidated. Evidence that syndecans are a class of receptor involved in cell adhesion is mounting, and their small cytoplasmic domains may link...

  17. Syndecan proteoglycans and cell adhesion

    DEFF Research Database (Denmark)

    Woods, A; Oh, E S; Couchman, J R

    1998-01-01

    It is now becoming clear that a family of transmembrane proteoglycans, the syndecans, have important roles in cell adhesion. They participate through binding of matrix ligand to their glycosaminoglycan chains, clustering, and the induction of signaling cascades to modify the internal microfilament...... organization. Syndecans can modulate the type of adhesive responses induced by other matrix ligand-receptor interactions, such as those involving the integrins, and so contribute to the control of cell morphology, adhesion and migration....

  18. Bio-active molecules modified surfaces enhanced mesenchymal stem cell adhesion and proliferation.

    Science.gov (United States)

    Mobasseri, Rezvan; Tian, Lingling; Soleimani, Masoud; Ramakrishna, Seeram; Naderi-Manesh, Hossein

    2017-01-29

    Surface modification of the substrate as a component of in vitro cell culture and tissue engineering, using bio-active molecules including extracellular matrix (ECM) proteins or peptides derived ECM proteins can modulate the surface properties and thereby induce the desired signaling pathways in cells. The aim of this study was to evaluate the behavior of human bone marrow mesenchymal stem cells (hBM-MSCs) on glass substrates modified with fibronectin (Fn), collagen (Coll), RGD peptides (RGD) and designed peptide (R-pept) as bio-active molecules. The glass coverslips were coated with fibronectin, collagen, RGD peptide and R-peptide. Bone marrow mesenchymal stem cells were cultured on different substrates and the adhesion behavior in early incubation times was investigated using scanning electron microscopy (SEM) and confocal microscopy. The MTT assay was performed to evaluate the effect of different bio-active molecules on MSCs proliferation rate during 24 and 72 h. Formation of filopodia and focal adhesion (FA) complexes, two steps of cell adhesion process, were observed in MSCs cultured on bio-active molecules modified coverslips, specifically in Fn coated and R-pept coated groups. SEM image showed well adhesion pattern for MSCs cultured on Fn and R-pept after 2 h incubation, while the shape of cells cultured on Coll and RGD substrates indicated that they might experience stress condition in early hours of culture. Investigation of adhesion behavior, as well as proliferation pattern, suggests R-peptide as a promising bio-active molecule to be used for surface modification of substrate in supporting and inducing cell adhesion and proliferation.

  19. Encapsulation of bioactive whey peptides in soy lecithin-derived nanoliposomes: Influence of peptide molecular weight.

    Science.gov (United States)

    Mohan, Aishwarya; McClements, David Julian; Udenigwe, Chibuike C

    2016-12-15

    Encapsulation of peptides can be used to enhance their stability, delivery and bioavailability. This study focused on the effect of the molecular weight range of whey peptides on their encapsulation within soy lecithin-derived nanoliposomes. Peptide molecular weight did not have a major impact on encapsulation efficiency or liposome size. However, it influenced peptide distribution amongst the surface, core, and bilayer regions of the liposomes, as determined by electrical charge (ζ-potential) and FTIR analysis. The liposome ζ-potential depended on peptide molecular weight, suggesting that the peptide charged groups were in different locations relative to the liposome surfaces. FTIR analysis indicated that the least hydrophobic peptide fractions interacted more strongly with choline on the liposome surfaces. The results suggested that the peptides were unequally distributed within the liposomes, even at the same encapsulation efficiency. These findings are important for designing delivery systems for commercial production of encapsulated peptides with improved functional attributes.

  20. Exenatide Alters Gene Expression of Neural Cell Adhesion Molecule (NCAM), Intercellular Cell Adhesion Molecule (ICAM), and Vascular Cell Adhesion Molecule (VCAM) in the Hippocampus of Type 2 Diabetic Model Mice

    Science.gov (United States)

    Gumuslu, Esen; Cine, Naci; Gökbayrak, Merve Ertan; Mutlu, Oguz; Celikyurt, Ipek Komsuoglu; Ulak, Guner

    2016-01-01

    Background Glucagon-like peptide-1 (GLP-1), a potent and selective agonist for the GLP-1 receptor, ameliorates the symptoms of diabetes through stimulation of insulin secretion. Exenatide is a potent and selective agonist for the GLP-1 receptor. Cell adhesion molecules are members of the immunoglobulin superfamily and are involved in synaptic rearrangements in the mature brain. Material/Methods The present study demonstrated the effects of exenatide treatment (0.1 μg/kg, subcutaneously, twice daily for 2 weeks) on the gene expression levels of cell adhesion molecules, neural cell adhesion molecule (NCAM), intercellular cell adhesion molecule (ICAM), and vascular cell adhesion molecule (VCAM) in the brain tissue of diabetic BALB/c male mice by real-time quantitative polymerase chain reaction (PCR). Diabetes was induced by streptozotocin/nicotinamide (STZ-NA) injection to male mice. Results The results of this study revealed that hippocampal gene expression of NCAM, ICAM, and VCAM were found to be up-regulated in STZ-NA-induced diabetic mice compared to those of controls. A significant decrease in the gene expression levels of NCAM, ICAM, and VCAM were determined after 2 weeks of exenatide administration. Conclusions Cell adhesion molecules may be involved in the molecular mechanism of diabetes. Exenatide has a strong beneficial action in managing diabetes induced by STZ/NA by altering gene expression of NCAM, ICAM, and VCAM. PMID:27465247

  1. Cell adhesion in embryo morphogenesis.

    Science.gov (United States)

    Barone, Vanessa; Heisenberg, Carl-Philipp

    2012-02-01

    Visualizing and analyzing shape changes at various scales, ranging from single molecules to whole organisms, are essential for understanding complex morphogenetic processes, such as early embryonic development. Embryo morphogenesis relies on the interplay between different tissues, the properties of which are again determined by the interaction between their constituent cells. Cell interactions, on the other hand, are controlled by various molecules, such as signaling and adhesion molecules, which in order to exert their functions need to be spatiotemporally organized within and between the interacting cells. In this review, we will focus on the role of cell adhesion functioning at different scales to organize cell, tissue and embryo morphogenesis. We will specifically ask how the subcellular distribution of adhesion molecules controls the formation of cell-cell contacts, how cell-cell contacts determine tissue shape, and how tissue interactions regulate embryo morphogenesis.

  2. Cell adhesion molecules and sleep.

    Science.gov (United States)

    O'Callaghan, Emma Kate; Ballester Roig, Maria Neus; Mongrain, Valérie

    2017-03-01

    Cell adhesion molecules (CAMs) play essential roles in the central nervous system, where some families are involved in synaptic development and function. These synaptic adhesion molecules (SAMs) are involved in the regulation of synaptic plasticity, and the formation of neuronal networks. Recent findings from studies examining the consequences of sleep loss suggest that these molecules are candidates to act in sleep regulation. This review highlights the experimental data that lead to the identification of SAMs as potential sleep regulators, and discusses results supporting that specific SAMs are involved in different aspects of sleep regulation. Further, some potential mechanisms by which SAMs may act to regulate sleep are outlined, and the proposition that these molecules may serve as molecular machinery in the two sleep regulatory processes, the circadian and homeostatic components, is presented. Together, the data argue that SAMs regulate the neuronal plasticity that underlies sleep and wakefulness. Copyright © 2016 Elsevier Ireland Ltd and Japan Neuroscience Society. All rights reserved.

  3. Effects of functionalization of PLGA-[Asp-PEG]n copolymer surfaces with Arg-Gly-Asp peptides, hydroxyapatite nanoparticles, and BMP-2-derived peptides on cell behavior in vitro.

    Science.gov (United States)

    Pan, Haitao; Zheng, Qixin; Yang, Shuhua; Guo, Xiaodong

    2014-12-01

    Functionalization of polymer surfaces has been recognized as a valuable tool to improve their properties that significantly influence cellular behaviors, such as adhesion, proliferation, migration, and differentiation. In stem cell-mediated bone tissue engineering, surface multifunctionalization of polymeric scaffolds with cell-adhesive, osteoconductive, and osteoinductive biomolecules is a critical strategy to improve such properties. However, the traditional surface modification techniques such as physical deposition/adsorption, chemical modification, grafting, and plasma techniques have great limitations for immobilization of multiple bioactive molecules due to multistep procedures. Recently, a universal technique based on mussel-inspired self-polymerization of dopamine is developed for multifunctional coatings in a simple way. In our study, we used this newly developed technique to incorporate three biomolecules, cell adhesion-promoting (K)16 GRGDSPC peptides, osteoconductive hydroxyapatite (HAp) nanoparticles, and osteoinductive bone morphogenetic protein-2-derived P24 peptides, to functionalize poly(lactide-co-glycolide) (PLGA)-[Asp-PEG]n scaffolds, and the effects on biological behaviors of co-cultured rabbit-derived bone marrow stromal cells in vitro were investigated. The results showed (K)16 GRGDSPC, HAp, and P24 could be immobilized onto the scaffolds through predeposition of polydopamine (pDA) ad-layer, and the surface-modified scaffolds were noncytotoxic as well as the virgin scaffold. The pDA-assisted codeposition of (K)16 GRGDSPC, HAp, and P24 on the scaffold surfaces significantly promoted cell adhesion, proliferation, osteodifferentiation, and mineralization in vitro with synergistic effects. Taken together, the functionalized PLGA-[Asp-PEG]n polymeric scaffolds achieved significantly elevated affinity, osteoconductive and osteoinductive ability, and may be a potentially promising bone graft substitute for bone repair. © 2014 Wiley Periodicals

  4. Antimicrobial and immunomodulatory activities of PR-39 derived peptides.

    Directory of Open Access Journals (Sweden)

    Edwin J A Veldhuizen

    Full Text Available The porcine cathelicidin PR-39 is a host defence peptide that plays a pivotal role in the innate immune defence of the pig against infections. Besides direct antimicrobial activity, it is involved in immunomodulation, wound healing and several other biological processes. In this study, the antimicrobial- and immunomodulatory activity of PR-39, and N- and C-terminal derivatives of PR-39 were tested. PR-39 exhibited an unexpected broad antimicrobial spectrum including several Gram positive strains such as Bacillus globigii and Enterococcus faecalis. Of organisms tested, only Staphylococcus aureus was insensitive to PR-39. Truncation of PR-39 down to 15 (N-terminal amino acids did not lead to major loss of activity, while peptides corresponding to the C-terminal part of PR-39 were hampered in their antimicrobial activity. However, shorter peptides were all much more sensitive to inhibition by salt. Active peptides induced ATP leakage and loss of membrane potential in Bacillus globigii and Escherichia coli, indicating a lytic mechanism of action for these peptides. Finally, only the mature peptide was able to induce IL-8 production in porcine macrophages, but some shorter peptides also had an effect on TNF-α production showing differential regulation of cytokine induction by PR-39 derived peptides. None of the active peptides showed high cytotoxicity highlighting the potential of these peptides for use as an alternative to antibiotics.

  5. Enhancement of Anti-Inflammatory and Osteogenic Abilities of Mesenchymal Stem Cells via Cell-to-Cell Adhesion to Periodontal Ligament-Derived Fibroblasts

    Science.gov (United States)

    Suzuki, Keita; Sawada, Shunsuke; Takizawa, Naoki; Yaegashi, Takashi; Ishisaki, Akira

    2017-01-01

    Mesenchymal stem cells (MSCs) are involved in anti-inflammatory events and tissue repair; these functions are activated by their migration or homing to inflammatory tissues in response to various chemokines. However, the mechanism by which MSCs interact with other cell types in inflammatory tissue remains unclear. We investigated the role of periodontal ligament fibroblasts (PDL-Fs) in regulating the anti-inflammatory and osteogenic abilities of bone marrow-derived- (BM-) MSCs. The expression of monocyte chemotactic protein- (MCP-)1 was significantly enhanced by stimulation of PDL-Fs with inflammatory cytokines. MCP-1 induced the migratory ability of BM-MSCs but not PDL-Fs. Expression levels of anti-inflammatory and inflammatory cytokines were increased and decreased, respectively, by direct-contact coculture between MSCs and PDL-Fs. In addition, the direct-contact coculture enhanced the expression of MSC markers that play important roles in the self-renewal and maintenance of multipotency of MSCs, which in turn induced the osteogenic ability of the cells. These results suggest that MCP-1 induces the migration and homing of BM-MSCs into the PDL inflammatory tissue. The subsequent adherence of MSCs to PDL-Fs plays an immunomodulatory role to terminate inflammation during wound healing and upregulates the expression stem cell markers to enhance the stemness of MSCs, thereby facilitating bone formation in damaged PDL tissue. PMID:28167967

  6. Enhancement of Anti-Inflammatory and Osteogenic Abilities of Mesenchymal Stem Cells via Cell-to-Cell Adhesion to Periodontal Ligament-Derived Fibroblasts

    Directory of Open Access Journals (Sweden)

    Keita Suzuki

    2017-01-01

    Full Text Available Mesenchymal stem cells (MSCs are involved in anti-inflammatory events and tissue repair; these functions are activated by their migration or homing to inflammatory tissues in response to various chemokines. However, the mechanism by which MSCs interact with other cell types in inflammatory tissue remains unclear. We investigated the role of periodontal ligament fibroblasts (PDL-Fs in regulating the anti-inflammatory and osteogenic abilities of bone marrow-derived- (BM- MSCs. The expression of monocyte chemotactic protein- (MCP-1 was significantly enhanced by stimulation of PDL-Fs with inflammatory cytokines. MCP-1 induced the migratory ability of BM-MSCs but not PDL-Fs. Expression levels of anti-inflammatory and inflammatory cytokines were increased and decreased, respectively, by direct-contact coculture between MSCs and PDL-Fs. In addition, the direct-contact coculture enhanced the expression of MSC markers that play important roles in the self-renewal and maintenance of multipotency of MSCs, which in turn induced the osteogenic ability of the cells. These results suggest that MCP-1 induces the migration and homing of BM-MSCs into the PDL inflammatory tissue. The subsequent adherence of MSCs to PDL-Fs plays an immunomodulatory role to terminate inflammation during wound healing and upregulates the expression stem cell markers to enhance the stemness of MSCs, thereby facilitating bone formation in damaged PDL tissue.

  7. Adsorption of enamel matrix proteins to a bovine-derived bone grafting material and its regulation of cell adhesion, proliferation, and differentiation.

    Science.gov (United States)

    Miron, Richard J; Bosshardt, Dieter D; Hedbom, Erik; Zhang, Yufeng; Haenni, Beat; Buser, Daniel; Sculean, Anton

    2012-07-01

    The use of various combinations of enamel matrix derivative (EMD) and grafting materials has been shown to promote periodontal wound healing/regeneration. However, the downstream cellular behavior of periodontal ligament (PDL) cells and osteoblasts has not yet been studied. Furthermore, it is unknown to what extent the bleeding during regenerative surgery may influence the adsorption of exogenous proteins to the surface of bone grafting materials and the subsequent cellular behavior. In the present study, the aim is to test EMD adsorption to the surface of natural bone mineral (NBM) particles in the presence of blood and determine the effect of EMD coating to NBM particles on downstream cellular pathways, such as adhesion, proliferation, and differentiation of primary human osteoblasts and PDL cells. NBM particles were precoated in various settings with EMD or human blood and analyzed for protein adsorption patterns via fluorescent imaging and high-resolution immunocytochemistry with an anti-EMD antibody. Cell attachment and cell proliferation were quantified using fluorescent double-stranded DNA-binding dye. Cell differentiation was analyzed using real-time polymerase chain reaction for genes encoding runt-related transcription factor 2, alkaline phosphatase (ALP), osteocalcin (OC), and collagen1α1 (COL1A1), and mineralization was assessed using red dye staining. Analysis of cell attachment and cell proliferation revealed significantly higher osteoblast and PDL cell attachment on EMD-coated surfaces when compared with control and blood-coated surfaces. EMD also stimulated release of growth factors and cytokines, including bone morphogenetic protein 2 and transforming growth factor β1. Moreover, there were significantly higher mRNA levels of osteoblast differentiation markers, including COL1A1, ALP, and OC, in osteoblasts and PDL cells cultured on EMD-coated NBM particles. The present results suggest that 1) EMD enhances osteoblast and PDL cell attachment

  8. Functional significance of bioactive peptides derived from soybean.

    Science.gov (United States)

    Singh, Brij Pal; Vij, Shilpa; Hati, Subrota

    2014-04-01

    Biologically active peptides play an important role in metabolic regulation and modulation. Several studies have shown that during gastrointestinal digestion, food processing and microbial proteolysis of various animals and plant proteins, small peptides can be released which possess biofunctional properties. These peptides are to prove potential health-enhancing nutraceutical for food and pharmaceutical applications. The beneficial health effects of bioactive peptides may be several like antihypertensive, antioxidative, antiobesity, immunomodulatory, antidiabetic, hypocholesterolemic and anticancer. Soybeans, one of the most abundant plant sources of dietary protein, contain 36-56% of protein. Recent studies showed that soy milk, an aqueous extract of soybean, and its fermented product have great biological properties and are a good source of bioactive peptides. This review focuses on bioactive peptides derived from soybean; we illustrate their production and biofunctional attributes.

  9. Covalent and stable CuAAC modification of silicon surfaces for control of cell adhesion

    DEFF Research Database (Denmark)

    Vutti, Surendra; Buch-Månson, Nina; Schoffelen, Sanne

    2015-01-01

    Stable primary functionalization of metal surfaces plays a significant role in reliable secondary attachment of complex functional molecules used for the interfacing of metal objects and nanomaterials with biological systems. In principle, this can be achieved through chemical reactions either......-transfer reaction. Subsequently, D-amino acid adhesion peptides could be immobilized on the surface by use of Cu(I)-catalyzed click chemistry. This enabled the study of cell adhesion to the metal surface. In contrast to unmodified surfaces, the peptide-modified surfaces were able to maintain cell adhesion during...

  10. Amygdalin influences bladder cancer cell adhesion and invasion in vitro

    OpenAIRE

    Jasmina Makarević; Jochen Rutz; Eva Juengel; Silke Kaulfuss; Igor Tsaur; Karen Nelson; Jesco Pfitzenmaier; Axel Haferkamp; Blaheta, Roman A

    2014-01-01

    The cyanogenic diglucoside amygdalin, derived from Rosaceae kernels, is employed by many patients as an alternative anti-cancer treatment. However, whether amygdalin indeed acts as an anti-tumor agent is not clear. Metastasis blocking properties of amygdalin on bladder cancer cell lines was, therefore, investigated. Amygdalin (10 mg/ml) was applied to UMUC-3, TCCSUP or RT112 bladder cancer cells for 24 h or for 2 weeks. Tumor cell adhesion to vascular endothelium or to immobilized collagen as...

  11. Chromogranin A-derived peptides are involved in innate immunity.

    Science.gov (United States)

    Aslam, R; Atindehou, M; Lavaux, T; Haïkel, Y; Schneider, F; Metz-Boutigue, M-H

    2012-01-01

    New endogenous antimicrobial peptides (AMPs) derived from chromogranin A (CgA) are secreted by nervous, endocrine and immune cells during stress. They display antimicrobial activities by lytic effects at micromolar range using a pore-forming mechanism against Gram-positive bacteria, filamentous fungi and yeasts. These AMPs can also penetrate quickly into neutrophils (without lytic effects), where, similarly to "cell penetrating peptides", they interact with cytoplasmic calmodulin, and induce calcium influx via Store Operated Channels therefore triggering neutrophils activation. Staphylococcus aureus and Salmonella enteritis are bacteria responsible for severe infections. We investigated here the effects of S. aureus and S. enteritis bacterial proteases on CgA-derived peptides and evaluated their antimicrobial activities. We showed that the Glu-C protease produced by S. aureus V8 induces the loss of the AMPs antibacterial activities and produces new antifungal peptides. In addition, four antimicrobial CGA-derived peptides (chromofungin, procatestatin, human/bovine catestatin) are degraded when treated with bacterial supernatants from S. aureus and S. enteritis, whereas, cateslytin, the short active form of catestatin, resists to this degradation. Finally, we demonstrate that several antimicrobial CgA-derived peptides are able to act synergistically with antibiotics against bacteria and fungi indicating their roles in innate defense.

  12. Novel histone-derived antimicrobial peptides use different antimicrobial mechanisms.

    Science.gov (United States)

    Pavia, Kathryn E; Spinella, Sara A; Elmore, Donald E

    2012-03-01

    The increase in multidrug resistant bacteria has sparked an interest in the development of novel antibiotics. Antimicrobial peptides that operate by crossing the cell membrane may also have the potential to deliver drugs to intracellular targets. Buforin 2 (BF2) is an antimicrobial peptide that shares sequence identity with a fragment of histone subunit H2A and whose bactericidal mechanism depends on membrane translocation and DNA binding. Previously, novel histone-derived antimicrobial peptides (HDAPs) were designed based on properties of BF2, and DesHDAP1 and DesHDAP3 showed significant antibacterial activity. In this study, their DNA binding, permeabilization, and translocation abilities were assessed independently and compared to antibacterial activity to determine whether they share a mechanism with BF2. To investigate the importance of proline in determining the peptides' mechanisms of action, proline to alanine mutants of the novel peptides were generated. DesHDAP1, which shows significant similarities to BF2 in terms of secondary structure, translocates effectively across lipid vesicle and bacterial membranes, while the DesHDAP1 proline mutant shows reduced translocation abilities and antimicrobial potency. In contrast, both DesHDAP3 and its proline mutant translocate poorly, though the DesHDAP3 proline mutant is more potent. Our findings suggest that a proline hinge can promote membrane translocation in some peptides, but that the extent of its effect on permeabilization depends on the peptide's amphipathic properties. Our results also highlight the different antimicrobial mechanisms exhibited by histone-derived peptides and suggest that histones may serve as a source of novel antimicrobial peptides with varied properties.

  13. Antiviral activity of ovotransferrin derived peptides.

    Science.gov (United States)

    Giansanti, Francesco; Massucci, M Teresa; Giardi, M Federica; Nozza, Fabrizio; Pulsinelli, Emy; Nicolini, Claudio; Botti, Dario; Antonini, Giovanni

    2005-05-27

    Ovotransferrin and lactoferrin are iron-binding proteins with antiviral and antibacterial activities related to natural immunity, showing marked sequence and structural homologies. The antiviral activity of two hen ovotransferrin fragments DQKDEYELL (hOtrf(219-227)) and KDLLFK (hOtrf(269-301) and hOtrf(633-638)) towards Marek's disease virus infection of chicken embryo fibroblasts is reported here. These fragments have sequence homology with two bovine lactoferrin fragments with antiviral activity towards herpes simplex virus, suggesting that these fragments could have a role for the exploitation of the antiviral activity of the intact proteins towards herpes viruses. NMR analysis showed that these peptides, chemically synthetized, did not possess any favourite conformation in solution, indicating that both the aminoacid sequence and the conformation they display in the intact protein are essential for the antiviral activity.

  14. Mixed Fibronectin-Derived Peptides Conjugated to a Chitosan Matrix Effectively Promotes Biological Activities through Integrins, α4β1, α5β1, αvβ3, and Syndecan

    Directory of Open Access Journals (Sweden)

    Hozumi Kentaro

    2016-11-01

    Full Text Available Mimicking the biological function of the extracellular matrix is an approach to developing cell adhesive biomaterials. The RGD peptide, derived from fibronectin (Fn, mainly binds to integrin αvβ3 and has been widely used as a cell adhesive peptide on various biomaterials. However, cell adhesion to Fn is thought to be mediated by several integrin subtypes and syndecans. In this study, we synthesized an RGD-containing peptide (FIB1 and four integrin α4β1-binding-related motif-containing peptides (LDV, IDAPS, KLDAPT, and PRARI and constructed peptide-chitosan matrices. The FIB1-chitosan matrix promoted human dermal fibroblast (HDF attachment, and the C-terminal elongated PRARI (ePRARI-C-conjugated chitosan matrix significantly promoted HDF attachment through integrin α4β1 and syndecan binding. Next, we constructed a mixed ePRARI-C- and FIB1-chitosan matrix to develop a Fn mimetic biomaterial. The mixed ePRARI-C/FIB1-chitosan matrix promoted significantly better cell attachment and neurite outgrowth compared to those of either ePRARI-C- or FIB1-chitosan matrices. HDF adhesion to the ePRARI-C/FIB1-chitosan matrix was mediated by integrin, α4β1, α5β1, and αvβ3, similar to HDF adhesion to Fn. These data suggest that an ePRARI-C/FIB1-chitosan matrix can be used as a tool to analyze the multiple functions of Fn and can serve as a Fn-mimetic biomaterial.

  15. Development of recombinant collagen-peptide-based vehicles for delivery of adipose-derived stromal cells.

    Science.gov (United States)

    Parvizi, Mojtaba; Plantinga, Josée A; van Speuwel-Goossens, Carolina A F M; van Dongen, Elisabeth M W M; Kluijtmans, Sebastiaan G J M; Harmsen, Martin C

    2016-02-01

    Stem cell therapy is a promising approach for repair, remodeling and even regenerate tissue of otherwise irreparable damage, such as after myocardial infarction (aMI). A severe limitation of cardiac stem cell therapy is the generally poor retention of administered cells in the target tissue. In tissue repair the main mode of action of adipose tissue-derived stem cells (ADSC) is the production of various growth factors, cytokines, anti-inflammatory and anti-apoptotic factors that together augment repair, remodeling, and regeneration. In this experiment, we used recombinant collagen peptide (RCP) with additional integrin-binding motives and different crosslinkers. Formulated as 50-100 μm microspheres with bound ADSC, we hypothesized that this would improve ADSC retention and function. Crosslinking was performed with chemical crosslinkers (EDC and HMDIC) at high and low concentrations or by thermal treatment (DHT). ADSC adhesion, proliferation, apoptosis/necrosis, and gene expressions in two-dimensional and three-dimensional were analyzed. In addition, the effect of ADSC conditioned medium (ADSC-CM) on proapoptotic/sprouting HUVEC was examined. Our results show that all materials support cell adhesion in short time point, however, EDC-High crosslinker induced ADSC apoptosis/necrosis. Gene expression results revealed lower expression of proinflammatory genes in chemical crosslinked materials, despite EDC-High the proinflammatory genes expressions were similar or higher than TCPS. In addition, cultured ADSC on DHT crosslinked RCP showed a proinflammatory phenotype compared to TCPS. Sprouting assay results confirmed the protective effect of ADSC-CM derived from TCPS and HMDIC-High crosslinked RCP proapoptotic HUVEC. We conclude that ADSC adhere to the materials and maintain their therapeutic profile.

  16. Cell-surface expression of neuron-glial antigen 2 (NG2) and melanoma cell adhesion molecule (CD146) in heterogeneous cultures of marrow-derived mesenchymal stem cells.

    Science.gov (United States)

    Russell, Katie C; Tucker, H Alan; Bunnell, Bruce A; Andreeff, Michael; Schober, Wendy; Gaynor, Andrew S; Strickler, Karen L; Lin, Shuwen; Lacey, Michelle R; O'Connor, Kim C

    2013-10-01

    Cellular heterogeneity of mesenchymal stem cells (MSCs) impedes their use in regenerative medicine. The objective of this research is to identify potential biomarkers for the enrichment of progenitors from heterogeneous MSC cultures. To this end, the present study examines variation in expression of neuron-glial antigen 2 (NG2) and melanoma cell adhesion molecule (CD146) on the surface of MSCs derived from human bone marrow in response to culture conditions and among cell populations. Multipotent cells isolated from heterogeneous MSC cultures exhibit a greater than three-fold increase in surface expression for NG2 and greater than two-fold increase for CD146 as compared with parental and lineage-committed MSCs. For both antigens, surface expression is downregulated by greater than or equal to six-fold when MSCs become confluent. During serial passage, maximum surface expression of NG2 and CD146 is associated with minimum doubling time. Upregulation of NG2 and CD146 during loss of adipogenic potential at early passage suggests some limits to their utility as potency markers. A potential relationship between proliferation and antigen expression was explored by sorting heterogeneous MSCs into rapidly and slowly dividing groups. Fluorescence-activated cell sorting revealed that rapidly dividing MSCs display lower scatter and 50% higher NG2 surface expression than slowly dividing cells, but CD146 expression is comparable in both groups. Heterogeneous MSCs were sorted based on scatter properties and surface expression of NG2 and CD146 into high (HI) and low (LO) groups. Sc(LO)NG2(HI) and Sc(LO)NG2(HI)CD146(HI) MSCs have the highest proliferative potential of the sorted groups, with colony-forming efficiencies that are 1.5-2.2 times the value for the parental controls. The Sc(LO) gate enriches for rapidly dividing cells. Addition of the NG2(HI) gate increases cell survival to 1.5 times the parental control. Further addition of the CD146(HI) gate does not significantly

  17. Decorated self-assembling β(3)-tripeptide foldamers form cell adhesive scaffolds.

    Science.gov (United States)

    Luder, Kerstin; Kulkarni, Ketav; Lee, Huey Wen; Widdop, Robert E; Del Borgo, Mark P; Aguilar, Marie-Isabel

    2016-03-25

    A popular strategy to control cellular growth and differentiation is the employment of self-assembling peptides as biomaterials. In this study we decorated ultrashort helical N-acetylated β-tripeptides with cell adhesion signals IKVAV and RGD, which spontaneously self-assemble to give nanofibres with multiple signals, and form a bioscaffold that supports the growth of cells.

  18. The effect of microstructured surfaces and laminin-derived peptide coatings on soft tissue interactions with titanium dental implants.

    Science.gov (United States)

    Werner, Sandra; Huck, Olivier; Frisch, Benoît; Vautier, Dominique; Elkaim, René; Voegel, Jean-Claude; Brunel, Gérard; Tenenbaum, Henri

    2009-04-01

    In the present study, we investigated the dental implant protection from peri-implant inflammation by improving the soft tissue adhesion on the titanium surface. Porous titanium was used to create, at the level of the transmucosal part of the implants (the "neck"), a microstructured 3-dimensional surface that would tightly seal the interface between the implant and soft tissue. Cell-specific adhesion properties were induced via an adhesion peptide derived from laminin-5 coupled to native or cross-linked PLL/PGA multilayered polyelectrolyte films (MPFs), which are used for biomedical device coatings. Porous titanium exhibited good cell-adhesion properties, but the colonisation of the material was further improved by a coating with laminin-5 functionalised MPFs and especially with (PLL/PGA)(6,5)-PGA-peptide film. Focal contact formation was observed on cross-linked architectures, reflecting cell anchorage on these surfaces. In contrast, when seeded on laminin-5-functionalised native films, epithelial cells formed only very diffuse focal contacts, but adhered via hemidesmosome formation. In vivo experiments confirmed that the porous titanium was colonised by cells of soft tissue. Altogether, the results indicate that the microstructure of the implant neck combined with a specific bioactive coating could constitute efficient routes to improve the integration of soft tissue on titanium dental implants, which could significantly protect implants from peri-implant inflammation and enhance long-term implant stabilisation.

  19. Antiinflammatory properties of a peptide derived from interleukin-4

    DEFF Research Database (Denmark)

    Klementiev, Boris; Enevoldsen, Maj N; Li, Shizhong

    2013-01-01

    Interleukin-4 (IL-4) is a potent antiinflammatory cytokine. However its use in the clinic is hampered by side effects. We here describe the identification of a novel synthetic peptide, termed Ph8, derived from α-helix C of IL-4, which interacts with IL-4 receptor α (IL-4Rα). Employing various...

  20. Photoperiod Regulates vgf-Derived Peptide Processing in Siberian Hamsters.

    Science.gov (United States)

    Noli, Barbara; Brancia, Carla; Pilleri, Roberta; D'Amato, Filomena; Messana, Irene; Manconi, Barbara; Ebling, Francis J P; Ferri, Gian-Luca; Cocco, Cristina

    2015-01-01

    VGF mRNA is induced in specific hypothalamic areas of the Siberian hamster upon exposure to short photoperiods, which is associated with a seasonal decrease in appetite and weight loss. Processing of VGF generates multiple bioactive peptides, so the objective of this study was to determine the profile of the VGF-derived peptides in the brain, pituitary and plasma from Siberian hamsters, and to establish whether differential processing might occur in the short day lean state versus long day fat. Antisera against short sequences at the C- or N- termini of proVGF, as well as against NERP-1, TPGH and TLQP peptides, were used for analyses of tissues, and both immunohistochemistry and enzyme linked immunosorbent assay (ELISA) coupled with high-performance liquid (HPLC) or gel chromatography were carried out. VGF peptide immunoreactivity was found within cortex cholinergic perikarya, in multiple hypothalamic nuclei, including those containing vasopressin, and in pituitary gonadotrophs. ELISA revealed that exposure to short day photoperiod led to a down-regulation of VGF immunoreactivity in the cortex, and a less pronounced decrease in the hypothalamus and pituitary, while the plasma VGF levels were not affected by the photoperiod. HPLC and gel chromatography both confirmed the presence of multiple VGF-derived peptides in these tissues, while gel chromatography showed the presence of the VGF precursor in all tissues tested except for the cortex. These observations are consistent with the view that VGF-derived peptides have pleiotropic actions related to changing photoperiod, possibly by regulating cholinergic systems in the cortex, vasopressin hypothalamic pathways, and the reproductive axis.

  1. Photoperiod Regulates vgf-Derived Peptide Processing in Siberian Hamsters.

    Directory of Open Access Journals (Sweden)

    Barbara Noli

    Full Text Available VGF mRNA is induced in specific hypothalamic areas of the Siberian hamster upon exposure to short photoperiods, which is associated with a seasonal decrease in appetite and weight loss. Processing of VGF generates multiple bioactive peptides, so the objective of this study was to determine the profile of the VGF-derived peptides in the brain, pituitary and plasma from Siberian hamsters, and to establish whether differential processing might occur in the short day lean state versus long day fat. Antisera against short sequences at the C- or N- termini of proVGF, as well as against NERP-1, TPGH and TLQP peptides, were used for analyses of tissues, and both immunohistochemistry and enzyme linked immunosorbent assay (ELISA coupled with high-performance liquid (HPLC or gel chromatography were carried out. VGF peptide immunoreactivity was found within cortex cholinergic perikarya, in multiple hypothalamic nuclei, including those containing vasopressin, and in pituitary gonadotrophs. ELISA revealed that exposure to short day photoperiod led to a down-regulation of VGF immunoreactivity in the cortex, and a less pronounced decrease in the hypothalamus and pituitary, while the plasma VGF levels were not affected by the photoperiod. HPLC and gel chromatography both confirmed the presence of multiple VGF-derived peptides in these tissues, while gel chromatography showed the presence of the VGF precursor in all tissues tested except for the cortex. These observations are consistent with the view that VGF-derived peptides have pleiotropic actions related to changing photoperiod, possibly by regulating cholinergic systems in the cortex, vasopressin hypothalamic pathways, and the reproductive axis.

  2. Food Derived Bioactive Peptides and Intestinal Barrier Function

    Directory of Open Access Journals (Sweden)

    Olga Martínez-Augustin

    2014-12-01

    Full Text Available A wide range of food-derived bioactive peptides have been shown to exert health-promoting actions and are therefore considered functional foods or nutraceuticals. Some of these actions are related to the maintenance, reinforcement or repairment of the intestinal barrier function (IBF whose role is to selectively allow the absorption of water, nutrients and ions while preventing the influx of microorganisms from the intestinal lumen. Alterations in the IBF have been related to many disorders, such as inflammatory bowel disease or metabolic syndrome. Components of IBF are the intestinal epithelium, the mucus layer, secretory immunoglobulin A and cells of the innate and adaptive immune systems. Here we review the effects of food derived bioactive peptides on these IBF components. In vitro and in vivo effects, both in healthy and disease states, have been reviewed. Although limited, the available information indicates a potential for food-derived peptides to modify IBF and to contribute to disease treatment, but further research is needed to better isolate responsible peptides, and to help define their mode of action.

  3. Neuritogenic and neuroprotective properties of peptide agonists of the fibroblast growth factor receptor

    DEFF Research Database (Denmark)

    Li, Shizhong; Bock, Elisabeth Marianne; Berezin, Vladimir

    2010-01-01

    Fibroblast growth factor receptors (FGFRs) interact with their cognate ligands, FGFs, and with a number of cell adhesion molecules (CAMs), such as the neural cell adhesion molecule (NCAM), mediating a wide range of events during the development and maintenance of the nervous system. Determination...... of protein structure, in silico modeling and biological studies have recently resulted in the identification of FGFR binding peptides derived from various FGFs and NCAM mimicking the effects of these molecules with regard to their neuritogenic and neuroprotective properties. This review focuses on recently...... developed functional peptide agonists of FGFR with possible therapeutic potential....

  4. Neuritogenic and Neuroprotective Properties of Peptide Agonists of the Fibroblast Growth Factor Receptor

    Directory of Open Access Journals (Sweden)

    Shizhong Li

    2010-05-01

    Full Text Available Fibroblast growth factor receptors (FGFRs interact with their cognate ligands, FGFs, and with a number of cell adhesion molecules (CAMs, such as the neural cell adhesion molecule (NCAM, mediating a wide range of events during the development and maintenance of the nervous system. Determination of protein structure, in silico modeling and biological studies have recently resulted in the identification of FGFR binding peptides derived from various FGFs and NCAM mimicking the effects of these molecules with regard to their neuritogenic and neuroprotective properties. This review focuses on recently developed functional peptide agonists of FGFR with possible therapeutic potential.

  5. Syndecans: synergistic activators of cell adhesion

    DEFF Research Database (Denmark)

    Woods, A; Couchman, J R

    1998-01-01

    Cell-surface proteoglycans participate in cell adhesion, growth-factor signalling, lipase activity and anticoagulation. Until recently, only the roles of the glycosaminoglycan chains were investigated. Now, with molecular characterization of several core proteins, the roles of each individual...... molecules modulating integrin-based adhesion....

  6. Cell adhesion signalling in acute renal failure

    NARCIS (Netherlands)

    Qin, Yu

    2011-01-01

    Acute renal failure (ARF) remains a severe clinical problem with high mortality. Little progress has been made over the past two decades in preventing renal injury or reducing mortality. This thesis describes the research to investigate cell adhesion alterations during the pathopysiology of both isc

  7. Depression-like behaviour in neural cell adhesion molecule (NCAM)-deficient mice and its reversal by an NCAM-derived peptide, FGL

    DEFF Research Database (Denmark)

    Aonurm-Helm, Anu; Jurgenson, Monika; Zharkovsky, Tamara

    2008-01-01

    in the sucrose preference test, reduced adult neurogenesis in the dentate gyrus and reduced levels of the phosphorylated cAMP response element-binding protein (pCREB) in the hippocampus. FGL administered acutely or repeatedly reduced depression-like behaviour in NCAM(-/-) mice without having an effect...

  8. Regulation of Cell Adhesion Strength by Peripheral Focal Adhesion Distribution

    OpenAIRE

    2011-01-01

    Cell adhesion to extracellular matrices is a tightly regulated process that involves the complex interplay between biochemical and mechanical events at the cell-adhesive interface. Previous work established the spatiotemporal contributions of adhesive components to adhesion strength and identified a nonlinear dependence on cell spreading. This study was designed to investigate the regulation of cell-adhesion strength by the size and position of focal adhesions (FA). The cell-adhesive interfac...

  9. Pharmacology of cell adhesion molecules of the nervous system

    DEFF Research Database (Denmark)

    Kiryushko, Darya; Bock, Elisabeth; Berezin, Vladimir

    2007-01-01

    development. The majority of CAMs are signal transducing receptors. CAM-induced intracellular signalling is triggered via homophilic (CAM-CAM) and heterophilic (CAM - other counter-receptors) interactions, which both can be targeted pharmacologically. We here describe the progress in the CAM pharmacology...... focusing on cadherins and CAMs of the immunoglobulin (Ig) superfamily, such as NCAM and L1. Structural basis of CAM-mediated cell adhesion and CAM-induced signalling are outlined. Different pharmacological approaches to study functions of CAMs are presented including the use of specific antibodies......, recombinant proteins, and synthetic peptides. We also discuss how unravelling of the 3D structure of CAMs provides novel pharmacological tools for dissection of CAM-induced signalling pathways and offers therapeutic opportunities for a range of neurological disorders....

  10. A synthetic peptide derivative that is a cholecystokinin receptor antagonist.

    Science.gov (United States)

    Lignon, M F; Galas, M C; Rodriguez, M; Laur, J; Aumelas, A; Martinez, J

    1987-05-25

    So far, there are no known peptidic effective receptor antagonists of both peripheral and central effects of cholecystokinin (CCK). Here, we describe a synthetic peptide derivative of CCK, t-butyloxycarbonyl-Tyr(SO3-)-Met-Gly-D-Trp-Nle-Asp 2-phenylethyl ester 1 (where Nle is norleucine), which is a potent CCK receptor antagonist. In rat and guinea pig dispersed pancreatic acini, this peptide derivative did not alter amylase secretion, but was able to antagonize the stimulation caused by cholecystokinin-related agonists. It caused a parallel rightward shift in the dose-response curve for the stimulation of amylase secretion with half-maximal inhibition of CCK-8-stimulated amylase release at a concentration of about 0.1 microM. Compound 1 was able to inhibit the binding of labeled CCK-9 (the C-terminal nonapeptide of CCK) to rat and guinea pig pancreatic acini (IC50 = 5 X 10(-8) M) as well as to guinea pig cerebral cortical membranes (IC50 = 5 X 10(-7) M). These results indicate that Compound 1 is a potent competitive CCK receptor antagonist.

  11. PFR peptide, one of the antimicrobial peptides identified from the derivatives of lactoferrin, induces necrosis in leukemia cells.

    Science.gov (United States)

    Lu, Yan; Zhang, Teng-Fei; Shi, Yue; Zhou, Han-Wei; Chen, Qi; Wei, Bu-Yun; Wang, Xi; Yang, Tian-Xin; Chinn, Y Eugene; Kang, Jian; Fu, Cai-Yun

    2016-02-10

    LF11-322 (PFWRIRIRR-NH2) (PFR peptide), a nine amino acid-residue peptide fragment derived from human lactoferricin, possesses potent cytotoxicity against bacteria. We report here the discovery and characterization of its antitumor activity in leukemia cells. PFR peptide inhibited the proliferation of MEL and HL-60 leukemia cells by inducing cell death in the absence of the classical features of apoptosis, including chromatin condensation, Annexin V staining, Caspase activation and increase of abundance of pro-apoptotic proteins. Instead, necrotic cell death as evidenced by increasing intracellular PI staining and LDH release, inducing membrane disruption and up-regulating intracellular calcium level, was observed following PFR peptide treatment. In addition to necrotic cell death, PFR peptide also induced G0/G1 cell cycle arrest. Moreover, PFR peptide exhibited favorable antitumor activity and tolerability in vivo. These findings thus provide a new clue of antimicrobial peptides as a potential novel therapy for leukemia.

  12. Convergent evolution-guided design of antimicrobial peptides derived from influenza A virus hemagglutinin.

    Science.gov (United States)

    Zhu, Shunyi; Aumelas, André; Gao, Bin

    2011-02-24

    Antimicrobial activity and solution structures of four 13-amino acid peptides derived from the fusion domain of viral hemagglutinin proteins are presented. The results show that carboxyl-terminal amidation is a key factor to switch a viral fusion domain-derived sequence into an antimicrobial peptide. Optimization of amphiphilic balance on the amidated analogue largely improves efficacy and enlarges antimicrobial spectra of these peptides. Our work indicates that viral fusion domains have potential to be engineered into potent antimicrobial peptides.

  13. PFR peptide, one of the antimicrobial peptides identified from the derivatives of lactoferrin, induces necrosis in leukemia cells

    OpenAIRE

    2016-01-01

    LF11-322 (PFWRIRIRR-NH2) (PFR peptide), a nine amino acid-residue peptide fragment derived from human lactoferricin, possesses potent cytotoxicity against bacteria. We report here the discovery and characterization of its antitumor activity in leukemia cells. PFR peptide inhibited the proliferation of MEL and HL-60 leukemia cells by inducing cell death in the absence of the classical features of apoptosis, including chromatin condensation, Annexin V staining, Caspase activation and increase o...

  14. Syndecans in tumor cell adhesion and signaling

    Directory of Open Access Journals (Sweden)

    Rapraeger Alan C

    2004-01-01

    Full Text Available Abstract Anchorage of cells to "heparin" – binding domains that are prevalent in extracellular matrix (ECM components is thought to occur primarily through the syndecans, a four-member family of transmembrane heparan sulfate proteoglycans that communicate environmental cues from the ECM to the cytoskeleton and the signaling apparatus of the cell. Known activities of the syndecans trace to their highly conserved cytoplasmic domains and to their heparan sulfate chains, which can serve to regulate the signaling of growth factors and morphogens. However, several emerging studies point to critical roles for the syndecans' extracellular protein domains in tumor cell behavior to include cell adhesion and invasion. Although the mechanisms of these activities remain largely unknown, one possibility involves "co-receptor" interactions with integrins that may regulate integrin function and the cell adhesion-signaling phenotype. Thus, alterations in syndecan expression, leading to either overexpression or loss of expression, both of which take place in tumor cells, may have dramatic effects on tumor cell invasion.

  15. Competition between bound and free peptides in an ELISA-based procedure that assays peptides derived from protein digests

    Directory of Open Access Journals (Sweden)

    Pace Umberto

    2006-05-01

    Full Text Available Abstract Background We describe an ELISA-based method that can be used to identify and quantitate proteins in biological samples. In this method, peptides in solution, derived from proteolytic digests of the sample, compete with substrate-attached synthetic peptides for antibodies, also in solution, generated against the chosen peptides. The peptides used for the ELISA are chosen on the basis of their being (i products of the proteolytic (e.g. tryptic digestion of the protein to be identified and (ii unique to the target protein, as far as one can know from the published sequences. Results In this paper we describe the competition assay and we define the optimal conditions for the most effective assay. We have performed an analysis of the kinetics of interaction between the four components of the assay: the plastic substratum to which the peptide is bound, the bound peptide itself, the competing added peptide, and the antibody that is specific for the peptide and we compare the results of theoretical simulations to the actual data in some model systems. Conclusion The data suggest that the peptides bind to the plastic substratum in more than one conformation and that, once bound, the peptide displays different affinities for the antibody, depending on how it has bound to the plate

  16. Differential expression of cell adhesion genes

    DEFF Research Database (Denmark)

    Stein, Wilfred D; Litman, Thomas; Fojo, Tito

    2005-01-01

    It is well known that tumors arising from tissues such as kidney, pancreas, liver and stomach are particularly refractory to treatment. Searching for new anticancer drugs using cells in culture has yielded some effective therapies, but these refractory tumors remain intractable. Studies that comp......It is well known that tumors arising from tissues such as kidney, pancreas, liver and stomach are particularly refractory to treatment. Searching for new anticancer drugs using cells in culture has yielded some effective therapies, but these refractory tumors remain intractable. Studies...... in cell adhesion and the cytoskeleton. If the proteins involved in tethering cells to the extracellular matrix are important in conferring drug resistance, it may be possible to improve chemotherapy by designing drugs that target these proteins....

  17. Three functions of cadherins in cell adhesion.

    Science.gov (United States)

    Maître, Jean-Léon; Heisenberg, Carl-Philipp

    2013-07-22

    Cadherins are transmembrane proteins that mediate cell-cell adhesion in animals. By regulating contact formation and stability, cadherins play a crucial role in tissue morphogenesis and homeostasis. Here, we review the three major functions of cadherins in cell-cell contact formation and stability. Two of those functions lead to a decrease in interfacial tension at the forming cell-cell contact, thereby promoting contact expansion--first, by providing adhesion tension that lowers interfacial tension at the cell-cell contact, and second, by signaling to the actomyosin cytoskeleton in order to reduce cortex tension and thus interfacial tension at the contact. The third function of cadherins in cell-cell contact formation is to stabilize the contact by resisting mechanical forces that pull on the contact.

  18. Gangliosides regulate tumor cell adhesion to collagen.

    Science.gov (United States)

    Kazarian, Tamara; Jabbar, Adnan A; Wen, Fei-Qui; Patel, Dharmesh A; Valentino, Leonard A

    2003-01-01

    The ability of tumor cells to adhere to extracellular matrix proteins is critical for migration and invasion. The factors that regulate tumor cell adhesion are poorly characterized. Gangliosides promote platelet adhesion and may also play a role in the adhesion of other cell types. We hypothesized that pharmacological depletion of membrane gangliosides from adherent cells would abrogate adhesion to collagen and promote migration and invasion. To test these hypotheses, LA-N1 neuroblastoma cells, which avidly adhere to collagen and are rich with membrane gangliosides (43.69 nmol/10(8) cells), were cultured in the presence of D-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol-HCl. Endogenous gangliosides were reduced by 98% (0.76 nmol/10(8) cells) and adhesion to collagen decreased by 67%. There were no changes in cell morphology, viability, proliferation rate or apoptosis. Pre-incubation of ganglioside-depleted cells in conditioned medium from control cells restored adhesion to collagen (0.45 +/- 0.002), comparable to that of control cells (0.49 +/- 0.035). Similarly, pre-incubation of ganglioside-depleted cells with purified GD2 completely restored adhesion in a concentration-dependent manner. When LA-N1 cells were cultured with retinoic acid, a biological response modifier known to increase endogenous gangliosides, adhesion to collagen increased. Next, we questioned whether changes in adhesion would be reflected as changes in migration and invasion. Cells depleted of endogenous cellular gangliosides migrated more than control cells. Finally, control cells replete with their endogenous gangliosides demonstrated less invasive potential than control cells. The data demonstrate that endogenous tumor gangliosides increase neuroblastoma cell adhesion to collagen and reduce migration and invasion in vitro.

  19. Milk-derived proteins and peptides in clinical trials

    Directory of Open Access Journals (Sweden)

    Jolanta Artym

    2013-08-01

    Full Text Available Clinical trials are reviewed, involving proteins and peptides derived from milk (predominantly bovine, with the exception of lactoferrin, which will be the subject of another article. The most explored milk fraction is α-lactalbumin (LA, which is often applied with glycomacropeptide (GMP – a casein degradation product. These milk constituents are used in health-promoting infant and adult formulae as well as in a modified form (HAMLET to treat cancer. Lactoperoxidase (LCP is used as an additive to mouth hygiene products and as a salivary substitute. Casein derivatives are applied, in addition, in the dry mouth syndrome. On the other hand, casein hydrolysates, containing active tripeptides, found application in hypertension and in type 2 diabetes. Lysozyme is routinely used for food conservation and in pharmaceutical products. It was successfully used in premature infants with concomitant diseases to improve health parameters. When used as prophylaxis in patients with scheduled surgery, it significantly reduced the incidence of hepatitis resulting from blood transfusion. Lysozyme was also used in infected children as an antimicrobial agent showing synergistic effects in combination with different antibiotics. Proline-rich polypeptide (PRP was introduced to therapy of Alzheimer’s disease patients. The therapeutic value of PRP was proved in several clinical trials and supported by studies on its mechanism of action. Concentrated immunoglobulin preparations from colostrum and milk of hyperimmunized cows showed efficacy in prevention of infections by bacteria, viruses and protozoa. A nutrition formula with milk-derived TGF-β2 (Modulen IBD® found application in treatment of pediatric Crohn’s disease. In conclusion, the preparations containing milk-derived products are safe and effective measures in prevention and treatment of infections as well as autoimmune and neoplastic diseases.

  20. Cell adhesion, inflammation and therapy: Old ideas and a significant step forward

    Institute of Scientific and Technical Information of China (English)

    Roberto GONZ(A)LEZ-AMARO

    2011-01-01

    Cell-to-cell adhesion as well as the interaction of cells with the extracellular matrix are key phenomena in different physiological and pathological conditions,including embryogenesis,blood coagulation,lymphocyte homing,immune response,angiogenesis,metastasis,thrombosis and inflammation[1,2].Thus,it has been widely proposed that cell adhesion molecules are an important therapeutic target in a wide array of diseases with high impact on public health,including atherosclerosis,thromboembolic disorders,cancer,graft rejection and autoimmune inflammatory conditions[1,2].However,anti-adhesion therapy with either biological agents (mainly blocking monoclonal antibodies,mAb's) or chemical inhibitors (mainly synthetic peptides) has not yet fulfilled these expectations and has not been devoid of undesirable effects[3,4

  1. Platelet Endothelial Cell Adhesion Molecule 1 (PECAM-1/CD31): A Multifunctional Vascular Cell Adhesion Molecule.

    Science.gov (United States)

    Delisser, H M; Baldwin, H S; Albelda, S M

    1997-08-01

    PECAM-1/CD31 is a member of the immunoglobulin gene superfamily found on platelets, leukocytes, and endothelial cells, where it concentrates at cell-cell borders. It has been shown to both mediate cell-cell adhesion through homophilic and heterophilic interactions and to transduce intracellular signals that upregulate the function of integrins on leukocytes. Its cellular distribution and ability to mediate adhesive and signaling phenomena suggested that PECAM-1 was a multifunctional vascular cell adhesion molecule involved in leukocyte-endothelial and endothelial-endothelial interactions. These initial suggestions have been largely confirmed as recent studies have implicated PECAM-1 in the inflammatory process and in the formation of blood vessels. As our understanding of the molecular and functional properties of PECAM-1 grows, new insights will be gained that may have therapeutic implications for cardiovascular development and disease. (Trends Cardiovasc Med 1997;7:203-210). © 1997, Elsevier Science Inc.

  2. Antimicrobial activity of human salivary mucin-derived peptides

    NARCIS (Netherlands)

    Wei, G.

    2008-01-01

    We investigated: a) relationships between molecular properties and antimicrobial functions of MUC7 peptides, b) effects of host physiological factors on the antimicrobial activity of MUC7 peptides, c) enhancement of antifungal activity by combination of MUC7 peptides with EDTA or other agents, d) an

  3. Determination of osteogenic or adipogenic lineages in muscle-derived stem cells (MDSCs) by a collagen-binding peptide (CBP) derived from bone sialoprotein (BSP)

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Yoon Jung [Dental Regenerative Biotechnology Major, School of Dentistry and Dental Research Institute, Seoul National University, Seoul 110-749 (Korea, Republic of); Lee, Jue Yeon [Research Institute, Nano Intelligent Biomedical Engineering Corporation (NIBEC), Seoul (Korea, Republic of); Lee, Seung Jin [Department of Industrial Pharmacy, College of Pharmacy, Ewha Womans University, Seoul (Korea, Republic of); Chung, Chong-Pyoung, E-mail: ccpperio@snu.ac.kr [Research Institute, Nano Intelligent Biomedical Engineering Corporation (NIBEC), Seoul (Korea, Republic of); Department of Periodontology, School of Dentistry and Dental Research Institute, Seoul National University, Seoul (Korea, Republic of); Park, Yoon Jeong, E-mail: parkyj@snu.ac.kr [Dental Regenerative Biotechnology Major, School of Dentistry and Dental Research Institute, Seoul National University, Seoul 110-749 (Korea, Republic of); Research Institute, Nano Intelligent Biomedical Engineering Corporation (NIBEC), Seoul (Korea, Republic of)

    2012-03-09

    Highlights: Black-Right-Pointing-Pointer CBP sequence is identified from BSP and has collagen binding activity. Black-Right-Pointing-Pointer CBP directly activates the MAPK signaling, especially ERK1/2. Black-Right-Pointing-Pointer CBP increase osteoblastic differentiation by the activation of Runx2. Black-Right-Pointing-Pointer CBP decrease adipogenic differentiation by the inhibition of PPAR{gamma}. -- Abstract: Bone sialoprotein (BSP) is a mineralized, tissue-specific, non-collagenous protein that is normally expressed only in mineralized tissues such as bone, dentin, cementum, and calcified cartilage, and at sites of new mineral formation. The binding of BSP to collagen is thought to be important for initiating bone mineralization and bone cell adhesion to the mineralized matrix. Several recent studies have isolated stem cells from muscle tissue, but their functional properties are still unclear. In this study, we examined the effects of a synthetic collagen-binding peptide (CBP) on the differentiation efficiency of muscle-derived stem cells (MDSCs). The CBP sequence (NGVFKYRPRYYLYKHAYFYPHLKRFPVQ) corresponds to residues 35-62 of bone sialoprotein (BSP), which are located within the collagen-binding domain in BSP. Interestingly, this synthetic CBP inhibited adipogenic differentiation but increased osteogenic differentiation in MDSCs. The CBP also induced expression of osteoblastic marker proteins, including alkaline phosphatase (ALP), type I collagen, Runt-related transcription factor 2 (Runx2), and osteocalcin; prevented adipogenic differentiation in MDSCs; and down-regulated adipose-specific mRNAs, such as adipocyte protein 2 (aP2) and peroxisome proliferator-activated receptor {gamma}. The CBP increased Extracellular signal-regulated kinases (ERK) 1/2 protein phosphorylation, which is important in lineage determination. These observations suggest that this CBP determines the osteogenic or adipogenic lineage in MDSCs by activating ERK1/2. Taken together, a

  4. in vitro development of bioimplants made up of elastomeric scaffolds with peptide gel filling seeded with human subcutaneous adipose tissue-derived progenitor cells.

    Science.gov (United States)

    Castells-Sala, Cristina; Martínez-Ramos, Cristina; Vallés-Lluch, Ana; Monleón Pradas, Manuel; Semino, Carlos

    2015-11-01

    Myocardial tissue lacks the ability to regenerate itself significantly following a myocardial infarction. Thus, new strategies that could compensate this lack are of high interest. Cardiac tissue engineering (CTE) strategies are a relatively new approach that aims to compensate the tissue loss using combination of biomaterials, cells and bioactive molecules. The goal of the present study was to evaluate cell survival and growth, seeding capacity and cellular phenotype maintenance of subcutaneous adipose tissue-derived progenitor cells in a new synthetic biomaterial scaffold platform. Specifically, here we tested the effect of the RAD16-I peptide gel in microporous poly(ethyl acrylate) polymers using two-dimensional PEA films as controls. Results showed optimal cell adhesion efficiency and growth in the polymers coated with the self-assembling peptide RAD16-I. Importantly, subATDPCs seeded into microporous PEA scaffolds coated with RAD16-I maintained its phenotype and were able to migrate outwards the bioactive patch, hopefully toward the infarcted area once implanted. These data suggest that this bioimplant (scaffold/RAD16-I/cells) can be suitable for further in vivo implantation with the aim to improve the function of affected tissue after myocardial infarction.

  5. Amygdalin influences bladder cancer cell adhesion and invasion in vitro.

    Science.gov (United States)

    Makarević, Jasmina; Rutz, Jochen; Juengel, Eva; Kaulfuss, Silke; Tsaur, Igor; Nelson, Karen; Pfitzenmaier, Jesco; Haferkamp, Axel; Blaheta, Roman A

    2014-01-01

    The cyanogenic diglucoside amygdalin, derived from Rosaceae kernels, is employed by many patients as an alternative anti-cancer treatment. However, whether amygdalin indeed acts as an anti-tumor agent is not clear. Metastasis blocking properties of amygdalin on bladder cancer cell lines was, therefore, investigated. Amygdalin (10 mg/ml) was applied to UMUC-3, TCCSUP or RT112 bladder cancer cells for 24 h or for 2 weeks. Tumor cell adhesion to vascular endothelium or to immobilized collagen as well as tumor cell migration was examined. Effects of drug treatment on integrin α and β subtypes, on integrin-linked kinase (ILK) and total and activated focal adhesion kinase (FAK) were also determined. Integrin knock-down was carried out to evaluate integrin influence on migration and adhesion. A 24 h or 2 week amygdalin application distinctly reduced tumor cell adhesion and migration of UMUC-3 and RT112 cells. TCCSUP adhesion was also reduced, but migration was elevated under amygdalin. Integrin subtype expression was significantly and specifically altered by amygdalin depending on the cell line. ILK was moderately, and activated FAK strongly, lost in all tumor cell lines in the presence of amygdalin. Knock down of β1 integrin caused a significant decrease in both adhesion and migration of UMUC-3 cells, but a significant increase in TCCSUP adhesion. Knock down of β4 integrin caused a significant decrease in migration of RT112 cells. Since the different actions of amygdalin on the different cell lines was mirrored by β1 or β4 knock down, it is postulated that amygdalin influences adhesion and migratory properties of bladder cancer cells by modulating β1 or β4 integrin expression. The amygdalin induced increase in TCCSUP migratory behavior indicates that any anti-tumor benefits from amygdalin (seen with the other two cell lines) may depend upon the cancer cell type.

  6. Amygdalin influences bladder cancer cell adhesion and invasion in vitro.

    Directory of Open Access Journals (Sweden)

    Jasmina Makarević

    Full Text Available The cyanogenic diglucoside amygdalin, derived from Rosaceae kernels, is employed by many patients as an alternative anti-cancer treatment. However, whether amygdalin indeed acts as an anti-tumor agent is not clear. Metastasis blocking properties of amygdalin on bladder cancer cell lines was, therefore, investigated. Amygdalin (10 mg/ml was applied to UMUC-3, TCCSUP or RT112 bladder cancer cells for 24 h or for 2 weeks. Tumor cell adhesion to vascular endothelium or to immobilized collagen as well as tumor cell migration was examined. Effects of drug treatment on integrin α and β subtypes, on integrin-linked kinase (ILK and total and activated focal adhesion kinase (FAK were also determined. Integrin knock-down was carried out to evaluate integrin influence on migration and adhesion. A 24 h or 2 week amygdalin application distinctly reduced tumor cell adhesion and migration of UMUC-3 and RT112 cells. TCCSUP adhesion was also reduced, but migration was elevated under amygdalin. Integrin subtype expression was significantly and specifically altered by amygdalin depending on the cell line. ILK was moderately, and activated FAK strongly, lost in all tumor cell lines in the presence of amygdalin. Knock down of β1 integrin caused a significant decrease in both adhesion and migration of UMUC-3 cells, but a significant increase in TCCSUP adhesion. Knock down of β4 integrin caused a significant decrease in migration of RT112 cells. Since the different actions of amygdalin on the different cell lines was mirrored by β1 or β4 knock down, it is postulated that amygdalin influences adhesion and migratory properties of bladder cancer cells by modulating β1 or β4 integrin expression. The amygdalin induced increase in TCCSUP migratory behavior indicates that any anti-tumor benefits from amygdalin (seen with the other two cell lines may depend upon the cancer cell type.

  7. SHORT PEDF-DERIVED PEPTIDE INHIBITS ANGIOGENESIS AND TUMOR GROWTH

    Science.gov (United States)

    Mirochnik, Yelena; Aurora, Arin; Schulze-Hoepfner, Frank T.; Deabes, Ahmed; Shifrin, Victor; Beckmann, Richard; Polsky, Charles; Volpert, Olga V.

    2010-01-01

    Purpose Pigment epithelial-derived factor (PEDF) is a potent angiogenesis inhibitor with multiple other functions, some of which enhance tumor growth. Our previous studies mapped PEDF anti-angiogenic and pro-survival activities to distinct epitopes. This study was aimed to determine the minimal fragment of PEDF, which maintains anti-angiogenic and anti-tumor efficacy. Experimental Design We analyzed antigenicity, hydrophilicity, and charge distribution of the angioinhibitory epitope (the 34-mer) and designed three peptides covering its C-terminus, P14, P18 and P23. We analyzed their ability to block endothelial cell (EC) chemotaxis and induce apoptosis in vitro and their anti-angiogenic activity in vivo. The selected peptide was tested for the anti-tumor activity against mildly aggressive xenografted prostate carcinoma and highly aggressive renal cell carcinoma. To verify that P18 acts in the same manner as PEDF, we used immunohistochemistry to measure PEDF targets, VEGFR2 and CD95L expression in P18-treated vasculature. Results P14 and P18 blocked endothelial cell chemotaxis; P18 and P23 induced apoptosis. P18 showed the highest IC50 and blocked angiogenesis in vivo: P23 was inactive and P14 was pro-angiogenic. P18 increased the production of CD95L and reduced the expression of VEGFR-2 by the endothelial cells in vivo. In tumor studies, P18 was more effective in blocking the angiogenesis and growth of the prostate cancer then parental 34-mer; in the renal cell carcinoma P18 strongly decreased angiogenesis and halted the progression of established tumors. Conclusions P18 is a novel and potent anti-angiogenic biotherapeutic agent, which has potential to be developed for the treatment of prostate and renal cancer. PMID:19223494

  8. Nylon-3 copolymers that generate cell-adhesive surfaces identified by library screening.

    Science.gov (United States)

    Lee, Myung-Ryul; Stahl, Shannon S; Gellman, Samuel H; Masters, Kristyn S

    2009-11-25

    Polymers in the nylon-3 family contain subunits derived from beta-amino acids, which are linked to one another via amide bonds. Thus, the nylon-3 backbone is homologous to the alpha-amino acid-based backbone of proteins. This molecular-level homology suggests that nylon-3 materials might be intrinsically protein-mimetic. The experiments described here explore this prospect in the context of cell adhesion, with tissue engineering as a long-range goal. We have evaluated a small library of sequence-random nylon-3 copolymers for the ability to render surfaces attractive to NIH 3T3 fibroblast adhesion and spreading. Library screening was accomplished in a high-throughput, parallel mode via attachment of the copolymers in a two-dimensional array to a modified glass surface. Significant variations in fibroblast adhesion and spreading were observed as a function of nylon-3 subunit identity and proportion. Several of the nylon-3 copolymers supported cell adhesion and morphology that was comparable, or even superior, to that achieved on positive control substrates such as tissue culture polystyrene and collagen-coated glass. Moreover, studies conducted under serum-free conditions demonstrated that specific nylon-3 derivatives supported cell adhesion independently of serum protein adsorption. Although cell adhesion was diminished in the absence of serum, particular copolymers demonstrated an ability to support substantially greater cell adhesion than any of the other conditions, including the positive controls. The nylon-3 copolymers that were most effective at promoting adhesion to a modified glass surface proved also to be effective at promoting adhesion when attached to a PEG-based hydrogel, demonstrating the potential for these copolymers to be used in tissue engineering applications.

  9. Tumor Antigen-Derived Peptides Delivery for Cancer Immunotherapy.

    Science.gov (United States)

    Wenxue, Ma

    2014-02-05

    Tumor antigenic peptides therapeutics is a promising field for cancer immunotherapy. Benefits include the ease and rapid synthesis of antigenic peptides and capacity for modifications. In the past years, many peptide-based cancer vaccines have been tested in clinical trials with a limited success because of the difficulties associated with peptide stability and delivery approaches, consequently, resulting in inefficient antigen presentation and low response rates in patients with cancer. The development of suitable and efficient vaccine carrier systems still remains a major challenge. This article aims to describe a new delivery approach for tumor antigenic peptides and rationales of dendritic cells (DCs)-based vaccination. In order to elicit enhanced immune responses, poly(DL-lactide-co-glycolide) (PLGA), which has been approved by the US Food and Drug Administration (FDA) for the use of drug delivery, diagnostics and other applications of clinical and basic science research were employed for the formulation of making nanoparticles (NPs) while delivering tumor antigenic peptides.

  10. Chemokine-Derived Peptides: Novel Antimicrobial and Antineoplasic Agents

    Science.gov (United States)

    Valdivia-Silva, Julio; Medina-Tamayo, Jaciel; Garcia-Zepeda, Eduardo A.

    2015-01-01

    Chemokines are a burgeoning family of chemotactic cytokines displaying a broad array of functions such as regulation of homeostatic leukocyte traffic and development, as well as activating the innate immune system. Their role in controlling early and late inflammatory stages is now well recognized. An improper balance either in chemokine synthesis or chemokine receptor expression contributes to various pathological disorders making chemokines and their receptors a useful therapeutic target. Research in this area is progressing rapidly, and development of novel agents based on chemokine/chemokine receptors antagonist functions are emerging as attractive alternative drugs. Some of these novel agents include generation of chemokine-derived peptides (CDP) with potential agonist and antagonist effects on inflammation, cancer and against bacterial infections. CDP have been generated mainly from N- and C-terminus chemokine sequences with subsequent modifications such as truncations or elongations. In this review, we present a glimpse of the different pharmacological actions reported for CDP and our current understanding regarding the potential use of CDP alone or as part of the novel therapies proposed in the treatment of microbial infections and cancer. PMID:26062132

  11. Chemokine-Derived Peptides: Novel Antimicrobial and Antineoplasic Agents

    Directory of Open Access Journals (Sweden)

    Julio Valdivia-Silva

    2015-06-01

    Full Text Available Chemokines are a burgeoning family of chemotactic cytokines displaying a broad array of functions such as regulation of homeostatic leukocyte traffic and development, as well as activating the innate immune system. Their role in controlling early and late inflammatory stages is now well recognized. An improper balance either in chemokine synthesis or chemokine receptor expression contributes to various pathological disorders making chemokines and their receptors a useful therapeutic target. Research in this area is progressing rapidly, and development of novel agents based on chemokine/ chemokine receptors antagonist functions are emerging as attractive alternative drugs. Some of these novel agents include generation of chemokine-derived peptides (CDP with potential agonist and antagonist effects on inflammation, cancer and against bacterial infections. CDP have been generated mainly from N- and C-terminus chemokine sequences with subsequent modifications such as truncations or elongations. In this review, we present a glimpse of the different pharmacological actions reported for CDP and our current understanding regarding the potential use of CDP alone or as part of the novel therapies proposed in the treatment of microbial infections and cancer.

  12. Regulation of cell adhesion strength by peripheral focal adhesion distribution.

    Science.gov (United States)

    Elineni, Kranthi Kumar; Gallant, Nathan D

    2011-12-21

    Cell adhesion to extracellular matrices is a tightly regulated process that involves the complex interplay between biochemical and mechanical events at the cell-adhesive interface. Previous work established the spatiotemporal contributions of adhesive components to adhesion strength and identified a nonlinear dependence on cell spreading. This study was designed to investigate the regulation of cell-adhesion strength by the size and position of focal adhesions (FA). The cell-adhesive interface was engineered to direct FA assembly to the periphery of the cell-spreading area to delineate the cell-adhesive area from the cell-spreading area. It was observed that redistributing the same adhesive area over a larger cell-spreading area significantly enhanced cell-adhesion strength, but only up to a threshold area. Moreover, the size of the peripheral FAs, which was interpreted as an adhesive patch, did not directly govern the adhesion strength. Interestingly, this is in contrast to the previously reported functional role of FAs in regulating cellular traction where sizes of the peripheral FAs play a critical role. These findings demonstrate, to our knowledge for the first time, that two spatial regimes in cell-spreading area exist that uniquely govern the structure-function role of FAs in regulating cell-adhesion strength.

  13. Marine algae-derived bioactive peptides for human nutrition and health.

    Science.gov (United States)

    Fan, Xiaodan; Bai, Lu; Zhu, Liang; Yang, Li; Zhang, Xuewu

    2014-09-24

    Within the parent protein molecule, most peptides are inactive, and they are released with biofunctionalities after enzymatic hydrolysis. Marine algae have high protein content, up to 47% of the dry weight, depending on the season and the species. Recently, there is an increasing interest in using marine algae protein as a source of bioactive peptides due to their health promotion and disease therapy potentials. This review presents an overview of marine algae-derived bioactive peptides and especially highlights some key issues, such as in silico proteolysis and quantitative structure-activity relationship studies, in vivo fate of bioactive peptides, and novel technologies in bioactive peptides studies and production.

  14. Drosophila neurotactin mediates heterophilic cell adhesion.

    Science.gov (United States)

    Barthalay, Y; Hipeau-Jacquotte, R; de la Escalera, S; Jiménez, F; Piovant, M

    1990-01-01

    Neurotactin is a 135 kd membrane glycoprotein which consists of a core protein, with an apparent molecular weight of 120 kd, and of N-linked oligosaccharides. In vivo, the protein can be phosphorylated in presence of radioactive orthophosphate. Neurotactin expression in the larval CNS and in primary embryonic cell cultures suggests that it behaves as a contact molecule between neurons or epithelial cells. Electron microscopy studies reveal that neurotactin is uniformly expressed along the areas of contacts between cells, without, however, being restricted to a particular type of junction. It putative adhesive properties have been tested by transfecting non adhesive Drosophila S2 cells with neurotactin cDNA. Heat shocked transfected cells do not aggregate, suggesting that neurotactin does not mediate homophilic cell adhesion. However, these transfected cells bind to a subpopulation of embryonic cells which probably possess a related ligand. The location at cellular junctions between specific neurons or epithelial cells, the heterophilic binding to a putative ligand and the ability to be phosphorylated are consistent with the suggestion that neurotactin functions as an adhesion molecule. Images Fig.1 Fig.2 Fig.3 Fig.4 Fig.5 PMID:2120048

  15. Cell adhesion during bullet motion in capillaries.

    Science.gov (United States)

    Takeishi, Naoki; Imai, Yohsuke; Ishida, Shunichi; Omori, Toshihiro; Kamm, Roger D; Ishikawa, Takuji

    2016-08-01

    A numerical analysis is presented of cell adhesion in capillaries whose diameter is comparable to or smaller than that of the cell. In contrast to a large number of previous efforts on leukocyte and tumor cell rolling, much is still unknown about cell motion in capillaries. The solid and fluid mechanics of a cell in flow was coupled with a slip bond model of ligand-receptor interactions. When the size of a capillary was reduced, the cell always transitioned to "bullet-like" motion, with a consequent decrease in the velocity of the cell. A state diagram was obtained for various values of capillary diameter and receptor density. We found that bullet motion enables firm adhesion of a cell to the capillary wall even for a weak ligand-receptor binding. We also quantified effects of various parameters, including the dissociation rate constant, the spring constant, and the reactive compliance on the characteristics of cell motion. Our results suggest that even under the interaction between P-selectin glycoprotein ligand-1 (PSGL-1) and P-selectin, which is mainly responsible for leukocyte rolling, a cell is able to show firm adhesion in a small capillary. These findings may help in understanding such phenomena as leukocyte plugging and cancer metastasis. Copyright © 2016 the American Physiological Society.

  16. Yielding elastic tethers stabilize robust cell adhesion.

    Directory of Open Access Journals (Sweden)

    Matt J Whitfield

    2014-12-01

    Full Text Available Many bacteria and eukaryotic cells express adhesive proteins at the end of tethers that elongate reversibly at constant or near constant force, which we refer to as yielding elasticity. Here we address the function of yielding elastic adhesive tethers with Escherichia coli bacteria as a model for cell adhesion, using a combination of experiments and simulations. The adhesive bond kinetics and tether elasticity was modeled in the simulations with realistic biophysical models that were fit to new and previously published single molecule force spectroscopy data. The simulations were validated by comparison to experiments measuring the adhesive behavior of E. coli in flowing fluid. Analysis of the simulations demonstrated that yielding elasticity is required for the bacteria to remain bound in high and variable flow conditions, because it allows the force to be distributed evenly between multiple bonds. In contrast, strain-hardening and linear elastic tethers concentrate force on the most vulnerable bonds, which leads to failure of the entire adhesive contact. Load distribution is especially important to noncovalent receptor-ligand bonds, because they become exponentially shorter lived at higher force above a critical force, even if they form catch bonds. The advantage of yielding is likely to extend to any blood cells or pathogens adhering in flow, or to any situation where bonds are stretched unequally due to surface roughness, unequal native bond lengths, or conditions that act to unzip the bonds.

  17. A family of cell-adhering peptides homologous to fibrinogen C-termini

    Energy Technology Data Exchange (ETDEWEB)

    Levy-Beladev, Liron [Institute of Chemistry, Safra Campus, Givat Ram, The Hebrew University of Jerusalem, Jerusalem 91904 (Israel); Levdansky, Lilia; Gaberman, Elena [Lab. of Biotechnology and Radiobiology, Hadassah-Hebrew University Medical Center, P.O. Box 12000, Jerusalem 91120 (Israel); Friedler, Assaf [Institute of Chemistry, Safra Campus, Givat Ram, The Hebrew University of Jerusalem, Jerusalem 91904 (Israel); Gorodetsky, Raphael, E-mail: Rafi@hadassah.org.il [Lab. of Biotechnology and Radiobiology, Hadassah-Hebrew University Medical Center, P.O. Box 12000, Jerusalem 91120 (Israel)

    2010-10-08

    Research highlights: {yields} Cell-adhesive sequences homologous to fibrinogen C-termini exist in other proteins. {yields} The extended homologous cell-adhesive C-termini peptides family is termed Haptides. {yields} In membrane-like environment random coiled Haptides adopt a helical conformation. {yields} Replacing positively charged residues with alanine reduces Haptides activity. -- Abstract: A family of cell-adhesive peptides homologous to sequences on different chains of fibrinogen was investigated. These homologous peptides, termed Haptides, include the peptides C{beta}, preC{gamma}, and C{alpha}E, corresponding to sequences on the C-termini of fibrinogen chains {beta}, {gamma}, and {alpha}E, respectively. Haptides do not affect cell survival and rate of proliferation of the normal cell types tested. The use of new sensitive assays of cell adhesion clearly demonstrated the ability of Haptides, bound to inert matrices, to mediate attachment of different matrix-dependent cell types including normal fibroblasts, endothelial, and smooth muscle cells. Here we present new active Haptides bearing homologous sequences derived from the C-termini of other proteins, such as angiopoietin 1 and 2, tenascins C and X, and microfibril-associated glycoprotein-4. The cell adhesion properties of all the Haptides were found to be associated mainly with their 11 N-terminal residues. Mutated preC{gamma} peptides revealed that positively charged residues account for their attachment effect. These results suggest a mechanism of direct electrostatic interaction of Haptides with the cell membrane. The extended Haptides family may be applied in modulating adhesion of cells to scaffolds for tissue regeneration and for enhancement of nanoparticulate transfection into cells.

  18. Analysis of the endogenous peptide profile of milk: identification of 248 mainly casein-derived peptides.

    Science.gov (United States)

    Baum, Florian; Fedorova, Maria; Ebner, Jennifer; Hoffmann, Ralf; Pischetsrieder, Monika

    2013-12-06

    Milk is an excellent source of bioactive peptides. However, the composition of the native milk peptidome has only been partially elucidated. The present study applied matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) directly or after prefractionation of the milk peptides by reverse-phase high-performance liquid chromatography (RP-HPLC) or OFFGEL fractionation for the comprehensive analysis of the peptide profile of raw milk. The peptide sequences were determined by MALDI-TOF/TOF or nano-ultra-performance liquid chromatography-nanoelectrospray ionization-LTQ-Orbitrap-MS. Direct MALDI-TOF-MS analysis led to the assignment of 57 peptides. Prefractionation by both complementary methods led to the assignment of another 191 peptides. Most peptides originate from α(S1)-casein, followed by β-casein, and α(S2)-casein. κ-Casein and whey proteins seem to play only a minor role as peptide precursors. The formation of many, but not all, peptides could be explained by the activity of the endogenous peptidases, plasmin or cathepsin D, B, and G. Database searches revealed the presence of 22 peptides with established physiological function, including those with angiotensin-converting-enzyme (ACE) inhibitory, immunomodulating, or antimicrobial activity.

  19. NCAM Mimetic Peptides: An Update

    DEFF Research Database (Denmark)

    Berezin, Vladimir; Bock, Elisabeth

    2008-01-01

    pharmacological tools interfering with NCAM functions. Recent progress in our understanding of the structural basis of NCAM-mediated cell adhesion and signaling has allowed a structure-based design of NCAM mimetic peptides. Using this approach a number of peptides termed P2, P1-B, P-3-DE and P-3-G, whose...... sequences contain one or several NCAM homophilic binding sites involved in NCAM binding to itself, have been identified. By means of NMR titration analysis and molecular modeling a number of peptides derived from NCAM and targeting NCAM heterophilic ligands such as the fibroblast growth factor receptor...... in vitro and in vivo, making them attractive pharmacological tools suitable for drug development for the treatment of neurodegenerative disorders and impaired memory....

  20. Bioactive peptides derived from milk proteins and their health beneficial potentials: an update.

    Science.gov (United States)

    Nagpal, Ravinder; Behare, Pradip; Rana, Rajiv; Kumar, Ashwani; Kumar, Manoj; Arora, Sanu; Morotta, Fransesco; Jain, Shalini; Yadav, Hariom

    2011-01-01

    It has been well recognized that dietary proteins provide a rich source of biologically active peptides. Today, milk proteins are considered the most important source of bioactive peptides and an increasing number of bioactive peptides have been identified in milk protein hydrolysates and fermented dairy products. Bioactive peptides derived from milk proteins offer a promising approach for the promotion of health by means of a tailored diet and provide interesting opportunities to the dairy industry for expansion of its field of operation. The potential health benefits of milk protein-derived peptides have been a subject of growing commercial interest in the context of health-promoting functional foods. Hence, these peptides are being incorporated in the form of ingredients in functional and novel foods, dietary supplements and even pharmaceuticals with the purpose of delivering specific health benefits.

  1. Milk protein-derived peptide inhibitors of angiotensin-I-converting enzyme

    OpenAIRE

    Fitzgerald, Richard J; Meisel, Hans

    2000-01-01

    peer-reviewed Numerous casein and whey protein-derived angiotensin-I-converting enzyme (ACE) inhibitory peptides/hydrolysates have been identified. Clinical trials in hypertensive animals and humans show that these peptides/hydrolysates can bring about a significant reduction in hypertension. These peptides/hydrolysates may be classified as functional food ingredients and nutraceuticals due to their ability to provide health benefits i.e. as functional food ingredients in reduc...

  2. Amine-functionalized polypyrrole: Inherently cell adhesive conducting polymer.

    Science.gov (United States)

    Lee, Jae Y; Schmidt, Christine E

    2015-06-01

    Electrically conducting polymers (CPs) have been recognized as novel biomaterials that can electrically communicate with biological systems. For their tissue engineering applications, CPs have been modified to promote cell adhesion for improved interactions between biomaterials and cells/tissues. Conventional approaches to improve cell adhesion involve the surface modification of CPs with biomolecules, such as physical adsorption of cell adhesive proteins and polycationic polymers, or their chemical immobilization; however, these approaches require additional multiple modification steps with expensive biomolecules. In this study, as a simple and effective alternative to such additional biomolecule treatment, we synthesized amine-functionalized polypyrrole (APPy) that inherently presents cell adhesion-supporting positive charges under physiological conditions. The synthesized APPy provides electrical activity in a moderate range and a hydrophilic surface compared to regular polypyrrole (PPy) homopolymers. Under both serum and serum-free conditions, APPy exhibited superior attachment of human dermal fibroblasts and Schwann cells compared to PPy homopolymer controls. Moreover, Schwann cell adhesion onto the APPy copolymer was at least similar to that on poly-l-lysine treated PPy controls. Our results indicate that amine-functionalized CP substrates will be useful to achieve good cell adhesion and potentially electrically stimulate various cells. In addition, amine functionality present on CPs can further serve as a novel and flexible platform to chemically tether various bioactive molecules, such as growth factors, antibodies, and chemical drugs. © 2014 Wiley Periodicals, Inc.

  3. Amplified effect of surface charge on cell adhesion by nanostructures

    Science.gov (United States)

    Xu, Li-Ping; Meng, Jingxin; Zhang, Shuaitao; Ma, Xinlei; Wang, Shutao

    2016-06-01

    Nano-biointerfaces with varied surface charge can be readily fabricated by integrating a template-based process with maleimide-thiol coupling chemistry. Significantly, nanostructures are employed for amplifying the effect of surface charge on cell adhesion, as revealed by the cell-adhesion performance, cell morphology and corresponding cytoskeletal organization. This study may provide a promising strategy for developing new biomedical materials with tailored cell adhesion for tissue implantation and regeneration.Nano-biointerfaces with varied surface charge can be readily fabricated by integrating a template-based process with maleimide-thiol coupling chemistry. Significantly, nanostructures are employed for amplifying the effect of surface charge on cell adhesion, as revealed by the cell-adhesion performance, cell morphology and corresponding cytoskeletal organization. This study may provide a promising strategy for developing new biomedical materials with tailored cell adhesion for tissue implantation and regeneration. Electronic supplementary information (ESI) available: Experimental details, SEM, KFM AFM, chemical modification and characterization. See DOI: 10.1039/c6nr00649c

  4. Small Peptides Derived from Penetratin as Antibacterial Agents.

    Science.gov (United States)

    Parravicini, Oscar; Somlai, Csaba; Andujar, Sebastián A; Garro, Adriana D; Lima, Beatriz; Tapia, Alejandro; Feresin, Gabriela; Perczel, Andras; Tóth, Gabor; Cascales, Javier López; Rodríguez, Ana M; Enriz, Ricardo D

    2016-04-01

    The synthesis, in vitro evaluation and conformational study of several small-size peptides acting as antibacterial agents are reported. Among the compounds evaluated, the peptides Arg-Gln-Ile-Lys-Ile-Trp-Arg-Arg-Met-Lys-Trp-Lys-Lys-NH2 , Arg-Gln-Ile-Lys-Ile-Arg-Arg-Met-Lys-Trp-Arg-NH2 , and Arg-Gln-Ile-Trp-Trp-Trp-Trp-Gln-Arg-NH2 exhibited significant antibacterial activity. These were found to be very active antibacterial compounds, considering their small molecular size. In order to better understand the antibacterial activity obtained for these peptides, an exhaustive conformational analysis was performed, using both theoretical calculations and experimental measurements. Molecular dynamics simulations using two different media (water and trifluoroethanol/water) were employed. The results of these theoretical calculations were corroborated by experimental circular dichroism measurements. A brief discussion on the possible mechanism of action of these peptides at molecular level is also presented. Some of the peptides reported here constitute very interesting structures to be used as starting compounds for the design of new small-size peptides possessing antibacterial activity.

  5. A non-local evolution equation model of cell-cell adhesion in higher dimensional space.

    Science.gov (United States)

    Dyson, Janet; Gourley, Stephen A; Webb, Glenn F

    2013-01-01

    A model for cell-cell adhesion, based on an equation originally proposed by Armstrong et al. [A continuum approach to modelling cell-cell adhesion, J. Theor. Biol. 243 (2006), pp. 98-113], is considered. The model consists of a nonlinear partial differential equation for the cell density in an N-dimensional infinite domain. It has a non-local flux term which models the component of cell motion attributable to cells having formed bonds with other nearby cells. Using the theory of fractional powers of analytic semigroup generators and working in spaces with bounded uniformly continuous derivatives, the local existence of classical solutions is proved. Positivity and boundedness of solutions is then established, leading to global existence of solutions. Finally, the asymptotic behaviour of solutions about the spatially uniform state is considered. The model is illustrated by simulations that can be applied to in vitro wound closure experiments.

  6. Antibacterial activity and dual mechanisms of peptide analog derived from cell-penetrating peptide against Salmonella typhimurium and Streptococcus pyogenes.

    Science.gov (United States)

    Li, Lirong; Shi, Yonghui; Cheserek, Maureen Jepkorir; Su, Guanfang; Le, Guowei

    2013-02-01

    A number of research have proven that antimicrobial peptides are of greatest potential as a new class of antibiotics. Antimicrobial peptides and cell-penetrating peptides share some similar structure characteristics. In our study, a new peptide analog, APP (GLARALTRLLRQLTRQLTRA) from the cell-penetrating peptide ppTG20 (GLFRALLRLLRSLWRLLLRA), was identified simultaneously with the antibacterial mechanism of APP against Salmonella typhimurium and Streptococcus pyogenes. APP displayed potent antibacterial activity against Gram-negative and Gram-positive strains. The minimum inhibitory concentration was in the range of 2 to 4 μM. APP displayed higher cell selectivity (about 42-fold increase) as compared to the parent peptide for it decreased hemolytic activity and increased antimicrobial activity. The calcein leakage from egg yolk L-α-phosphatidylcholine (EYPC)/egg yolk L-α-phosphatidyl-DL-glycerol and EYPC/cholesterol vesicles demonstrated that APP exhibited high selectivity. The antibacterial mechanism analysis indicated that APP induced membrane permeabilization in a kinetic manner for membrane lesions allowing O-nitrophenyl-β-D-galactoside uptake into cells and potassium release from APP-treated cells. Flow cytometry analysis demonstrated that APP induced bacterial live cell membrane damage. Circular dichroism, fluorescence spectra, and gel retardation analysis confirmed that APP interacted with DNA and intercalated into the DNA base pairs after penetrating the cell membrane. Cell cycle assay showed that APP affected DNA synthesis in the cell. Our results suggested that peptides derived from the cell-penetrating peptide have the potential for antimicrobial agent development, and APP exerts its antibacterial activity by damaging bacterial cell membranes and binding to bacterial DNA to inhibit cellular functions, ultimately leading to cell death.

  7. Scorpion venom heat-resistant peptide (SVHRP) enhances neurogenesis and neurite outgrowth of immature neurons in adult mice by up-regulating brain-derived neurotrophic factor (BDNF).

    Science.gov (United States)

    Wang, Tao; Wang, Shi-Wei; Zhang, Yue; Wu, Xue-Fei; Peng, Yan; Cao, Zhen; Ge, Bi-Ying; Wang, Xi; Wu, Qiong; Lin, Jin-Tao; Zhang, Wan-Qin; Li, Shao; Zhao, Jie

    2014-01-01

    Scorpion venom heat-resistant peptide (SVHRP) is a component purified from Buthus martensii Karsch scorpion venom. Although scorpions and their venom have been used in Traditional Chinese Medicine (TCM) to treat chronic neurological disorders, the underlying mechanisms of these treatments remain unknown. We applied SVHRP in vitro and in vivo to understand its effects on the neurogenesis and maturation of adult immature neurons and explore associated molecular mechanisms. SVHRP administration increased the number of 5-bromo-2'-dexoxyuridine (BrdU)-positive cells, BrdU-positive/neuron-specific nuclear protein (NeuN)-positive neurons, and polysialylated-neural cell adhesion molecule (PSA-NCAM)-positive immature neurons in the subventricular zone (SVZ) and subgranular zone (SGZ) of hippocampus. Furthermore immature neurons incubated with SVHRP-pretreated astrocyte-conditioned medium exhibited significantly increased neurite length compared with those incubated with normal astrocyte-conditioned medium. This neurotrophic effect was further confirmed in vivo by detecting an increased average single area and whole area of immature neurons in the SGZ, SVZ and olfactory bulb (OB) in the adult mouse brain. In contrast to normal astrocyte-conditioned medium, higher concentrations of brain-derived neurotrophic factor (BDNF) but not nerve growth factor (NGF) or glial cell line-derived neurotrophic factor (GDNF) was detected in the conditioned medium of SVHRP-pretreated astrocytes, and blocking BDNF using anti-BDNF antibodies eliminated these SVHRP-dependent neurotrophic effects. In SVHRP treated mouse brain, more glial fibrillary acidic protein (GFAP)-positive cells were detected. Furthermore, immunohistochemistry revealed increased numbers of GFAP/BDNF double-positive cells, which agrees with the observed changes in the culture system. This paper describes novel effects of scorpion venom-originated peptide on the stem cells and suggests the potential therapeutic values of SVHRP.

  8. Scorpion venom heat-resistant peptide (SVHRP enhances neurogenesis and neurite outgrowth of immature neurons in adult mice by up-regulating brain-derived neurotrophic factor (BDNF.

    Directory of Open Access Journals (Sweden)

    Tao Wang

    Full Text Available Scorpion venom heat-resistant peptide (SVHRP is a component purified from Buthus martensii Karsch scorpion venom. Although scorpions and their venom have been used in Traditional Chinese Medicine (TCM to treat chronic neurological disorders, the underlying mechanisms of these treatments remain unknown. We applied SVHRP in vitro and in vivo to understand its effects on the neurogenesis and maturation of adult immature neurons and explore associated molecular mechanisms. SVHRP administration increased the number of 5-bromo-2'-dexoxyuridine (BrdU-positive cells, BrdU-positive/neuron-specific nuclear protein (NeuN-positive neurons, and polysialylated-neural cell adhesion molecule (PSA-NCAM-positive immature neurons in the subventricular zone (SVZ and subgranular zone (SGZ of hippocampus. Furthermore immature neurons incubated with SVHRP-pretreated astrocyte-conditioned medium exhibited significantly increased neurite length compared with those incubated with normal astrocyte-conditioned medium. This neurotrophic effect was further confirmed in vivo by detecting an increased average single area and whole area of immature neurons in the SGZ, SVZ and olfactory bulb (OB in the adult mouse brain. In contrast to normal astrocyte-conditioned medium, higher concentrations of brain-derived neurotrophic factor (BDNF but not nerve growth factor (NGF or glial cell line-derived neurotrophic factor (GDNF was detected in the conditioned medium of SVHRP-pretreated astrocytes, and blocking BDNF using anti-BDNF antibodies eliminated these SVHRP-dependent neurotrophic effects. In SVHRP treated mouse brain, more glial fibrillary acidic protein (GFAP-positive cells were detected. Furthermore, immunohistochemistry revealed increased numbers of GFAP/BDNF double-positive cells, which agrees with the observed changes in the culture system. This paper describes novel effects of scorpion venom-originated peptide on the stem cells and suggests the potential therapeutic values

  9. Functional ontogeny of the proglucagon-derived peptide axis in the premature human neonate

    DEFF Research Database (Denmark)

    Amin, Harish; Holst, Jens Juul; Hartmann, Bolette

    2008-01-01

    assimilation, intestinal growth, and function. OBJECTIVE: Our goal was to investigate the production of glucagon-like peptides 1 and 2 in premature human infants and examine the effects of prematurity and feeding on hormone release. PATIENTS AND METHODS: With informed consent, premature infants who were...... levels of both glucagon-like peptides 1 and 2 were elevated. There was no correlation between gestational age and glucagon-like peptide 2 output. However, both glucagon-like peptide 1 and 2 levels were correlated with the caloric value of feeds. CONCLUSIONS: The premature human neonate has significantly...... higher fasting levels of glucagon-like peptides 1 and 2 compared with adults; feeding increases these levels further. These findings suggest that the proglucagon-derived peptides may have a role in normal intestinal development and nutrient handling....

  10. Insights into the evolution of proglucagon-derived peptides and receptors in fish and amphibians.

    Science.gov (United States)

    Ng, Stephanie Y L; Lee, Leo T O; Chow, Billy K C

    2010-07-01

    Glucagon and the glucagon-like peptides (GLP-1 and GLP-2) share a common evolutionary origin and are triplication products of an ancestral glucagon exon. In mammals, a standard scenario is found where only a single proglucagon-derived peptide set exists. However, fish and amphibians have either multiple proglucagon genes or exons that are likely resultant of duplication events. Through phylogenetic analysis and examination of their respective functions, the proglucagon ligand-receptor pairs are believed to have evolved independently before acquiring specificity for one another. This review will provide a comprehensive overview of current knowledge of proglucagon-derived peptides and receptors, with particular focus on fish and amphibian species.

  11. Basal Lamina Mimetic Nanofibrous Peptide Networks for Skeletal Myogenesis

    Science.gov (United States)

    Yasa, I. Ceren; Gunduz, Nuray; Kilinc, Murat; Guler, Mustafa O.; Tekinay, Ayse B.

    2015-11-01

    Extracellular matrix (ECM) is crucial for the coordination and regulation of cell adhesion, recruitment, differentiation and death. Therefore, equilibrium between cell-cell and cell-matrix interactions and matrix-associated signals are important for the normal functioning of cells, as well as for regeneration. In this work, we describe importance of adhesive signals for myoblast cells’ growth and differentiation by generating a novel ECM mimetic peptide nanofiber scaffold system. We show that not only structure but also composition of bioactive signals are important for cell adhesion, growth and differentiation by mimicking the compositional and structural properties of native skeletal muscle basal lamina. We conjugated laminin-derived integrin binding peptide sequence, “IKVAV”, and fibronectin-derived well known adhesive sequence, “RGD”, into peptide nanostructures to provide adhesive and myogenic cues on a nanofibrous morphology. The myogenic and adhesive signals exhibited a synergistic effect on model myoblasts, C2C12 cells. Our results showed that self-assembled peptide nanofibers presenting laminin derived epitopes support adhesion, growth and proliferation of the cells and significantly promote the expression of skeletal muscle-specific marker genes. The functional peptide nanofibers used in this study present a biocompatible and biodegradable microenvironment, which is capable of supporting the growth and differentiation of C2C12 myoblasts into myotubes.

  12. Inhibition of the ferric uptake regulator by peptides derived from anti-FUR peptide aptamers: coupled theoretical and experimental approaches.

    Science.gov (United States)

    Cissé, Cheickna; Mathieu, Sophie V; Abeih, Mohamed B Ould; Flanagan, Lindsey; Vitale, Sylvia; Catty, Patrice; Boturyn, Didier; Michaud-Soret, Isabelle; Crouzy, Serge

    2014-12-19

    The FUR protein (ferric uptake regulator) is an iron-dependent global transcriptional regulator. Specific to bacteria, FUR is an attractive antibacterial target since virulence is correlated to iron bioavailability. Recently, four anti-FUR peptide aptamers, composed of 13 amino acid variable loops inserted into a thioredoxinA scaffold, were identified, which were able to interact with Escherichia coli FUR (EcFUR), inhibit its binding to DNA and to decrease the virulence of pathogenic E. coli in a fly infection model. The first characterization of anti-FUR linear peptides (pF1 6 to 13 amino acids) derived from the variable part of the F1 anti-FUR peptide aptamer is described herein. Theoretical and experimental approaches, in original combination, were used to study interactions of these peptides with FUR in order to understand their mechanism of inhibition. After modeling EcFUR by homology, docking with Autodock was combined with molecular dynamics simulations in implicit solvent to take into account the flexibility of the partners. All calculations were cross-checked either with other programs or with experimental data. As a result, reliable structures of EcFUR and its complex with pF1 are given and an inhibition pocket formed by the groove between the two FUR subunits is proposed. The location of the pocket was validated through experimental mutation of key EcFUR residues at the site of proposed peptide interaction. Cyclisation of pF1, mimicking the peptide constraint in F1, improved inhibition. The details of the interactions between peptide and protein were analyzed and a mechanism of inhibition of these anti-FUR molecules is proposed.

  13. Regulation of embryonic cell adhesion by the prion protein.

    Directory of Open Access Journals (Sweden)

    Edward Málaga-Trillo

    2009-03-01

    Full Text Available Prion proteins (PrPs are key players in fatal neurodegenerative disorders, yet their physiological functions remain unclear, as PrP knockout mice develop rather normally. We report a strong PrP loss-of-function phenotype in zebrafish embryos, characterized by the loss of embryonic cell adhesion and arrested gastrulation. Zebrafish and mouse PrP mRNAs can partially rescue this knockdown phenotype, indicating conserved PrP functions. Using zebrafish, mouse, and Drosophila cells, we show that PrP: (1 mediates Ca(+2-independent homophilic cell adhesion and signaling; and (2 modulates Ca(+2-dependent cell adhesion by regulating the delivery of E-cadherin to the plasma membrane. In vivo time-lapse analyses reveal that the arrested gastrulation in PrP knockdown embryos is due to deficient morphogenetic cell movements, which rely on E-cadherin-based adhesion. Cell-transplantation experiments indicate that the regulation of embryonic cell adhesion by PrP is cell-autonomous. Moreover, we find that the local accumulation of PrP at cell contact sites is concomitant with the activation of Src-related kinases, the recruitment of reggie/flotillin microdomains, and the reorganization of the actin cytoskeleton, consistent with a role of PrP in the modulation of cell adhesion via signaling. Altogether, our data uncover evolutionarily conserved roles of PrP in cell communication, which ultimately impinge on the stability of adherens cell junctions during embryonic development.

  14. Fiber formation of a synthetic spider peptide derived from Nephila clavata.

    Science.gov (United States)

    Hidaka, Yuji; Kontani, Ko-Ichi; Taniguchi, Rina; Saiki, Masatoshi; Yokoi, Sayoko; Yukuhiro, Kenji; Yamaguchi, Hiroshi; Miyazawa, Mitsuhiro

    2011-01-01

    Dragline silk is a high-performance biopolymer with exceptional mechanical properties. Artificial spider dragline silk is currently prepared by a recombinant technique or chemical synthesis. However, the recombinant process is costly and large-sized synthetic peptides are needed for fiber formation. In addition, the silk fibers that are produced are much weaker than a fiber derived from a native spider. In this study, a small peptide was chemically synthesized and examined for its ability to participate in fiber formation. A short synthetic peptide derived from Nephila clavata was prepared by a solid-phase peptide method, based on a prediction using the hydrophobic parameter of each individual amino acid residue. After purification of the spider peptide, fiber formation was examined under several conditions. Fiber formation proceeded in the acidic pH range, and larger fibers were produced when organic solvents such as trifluoroethanol and acetonitrile were used at an acidic pH. Circular dichroism measurements of the spider peptide indicate that the peptide has a beta-sheet structure and that the formation of a beta-sheet structure is required for the spider peptide to undergo fiber formation.

  15. Bioactive hydrogels made from step-growth derived PEG-peptide macromers.

    Science.gov (United States)

    Miller, Jordan S; Shen, Colette J; Legant, Wesley R; Baranski, Jan D; Blakely, Brandon L; Chen, Christopher S

    2010-05-01

    Synthetic hydrogels based on poly(ethylene glycol) (PEG) have been used as biomaterials for cell biology and tissue engineering investigations. Bioactive PEG-based gels have largely relied on heterobifunctional or multi-arm PEG precursors that can be difficult to synthesize and characterize or expensive to obtain. Here, we report an alternative strategy, which instead uses inexpensive and readily available PEG precursors to simplify reactant sourcing. This new approach provides a robust system in which to probe cellular interactions with the microenvironment. We used the step-growth polymerization of PEG diacrylate (PEGDA, 3400Da) with bis-cysteine matrix metalloproteinase (MMP)-sensitive peptides via Michael-type addition to form biodegradable photoactive macromers of the form acrylate-PEG-(peptide-PEG)(m)-acrylate. The molecular weight (MW) of these macromers is controlled by the stoichiometry of the reaction, with a high proportion of resultant macromer species greater than 500kDa. In addition, the polydispersity of these materials was nearly identical for three different MMP-sensitive peptide sequences subjected to the same reaction conditions. When photopolymerized into hydrogels, these high MW materials exhibit increased swelling and sensitivity to collagenase-mediated degradation as compared to previously published PEG hydrogel systems. Cell-adhesive acrylate-PEG-CGRGDS was synthesized similarly and its immobilization and stability in solid hydrogels was characterized with a modified Lowry assay. To illustrate the functional utility of this approach in a biological setting, we applied this system to develop materials that promote angiogenesis in an ex vivo aortic arch explant assay. We demonstrate the formation and invasion of new sprouts mediated by endothelial cells into the hydrogels from embedded embryonic chick aortic arches. Furthermore, we show that this capillary sprouting and three-dimensional migration of endothelial cells can be tuned by

  16. Peptide vaccination against multiple myeloma using peptides derived from anti-apoptotic proteins

    DEFF Research Database (Denmark)

    Jørgensen, Nicolai Grønne; Ahmad, Shamaila Munir; Abildgaard, Niels

    2016-01-01

    The B-cell lymphoma-2 (Bcl-2) family of proteins play a crucial role in multiple myeloma (MM), contributing to lacking apoptosis which is a hallmark of the disease. This makes the Bcl-2 proteins interesting targets for therapeutic peptide vaccination. We report a phase I trial of therapeutic...... vaccination with peptides from the proteins Bcl-2, Bcl-XL and Mcl-1 in patients with relapsed MM. Vaccines were given concomitant with bortezomib. Out of 7 enrolled patients, 4 received the full course of 8 vaccinations. The remaining 3 patients received fewer vaccinations due to progression, clinical...... decision of lacking effect and development of hypercalcemia, respectively. There were no signs of toxicity other than what was to be expected from bortezomib. Immune responses to the peptides were seen in all 6 patients receiving more than 2 vaccinations. Three patients had increased immune responses after...

  17. Bioavailability of milk protein-derived bioactive peptides: a glycaemic management perspective.

    Science.gov (United States)

    Horner, Katy; Drummond, Elaine; Brennan, Lorraine

    2016-06-01

    Milk protein-derived peptides have been reported to have potential benefits for reducing the risk of type 2 diabetes. However, what the active components are and whether intact peptides exert this bioactivity has received little investigation in human subjects. Furthermore, potentially useful bioactive peptides can be limited by low bioavailability. Various peptides have been identified in the gastrointestinal tract and bloodstream after milk-protein ingestion, providing valuable insights into their potential bioavailability. However, these studies are currently limited and the structure and sequence of milk peptides exerting bioactivity for glycaemic management has received little investigation in human subjects. The present article reviews the bioavailability of milk protein-derived peptides in human studies to date, and examines the evidence on milk proteins and glycaemic management, including potential mechanisms of action. Areas in need of advancement are identified. Only by establishing the bioavailability of milk protein-derived peptides, the active components and the mechanistic pathways involved can the benefits of milk proteins for the prevention or management of type 2 diabetes be fully realised in future.

  18. An overview of antifungal peptides derived from insect.

    Science.gov (United States)

    Faruck, Mohammad Omer; Yusof, Faridah; Chowdhury, Silvia

    2016-06-01

    Fungi are not classified as plants or animals. They resemble plants in many ways but do not produce chlorophyll or make their own food photosynthetically like plants. Fungi are useful for the production of beer, bread, medicine, etc. More complex than viruses or bacteria; fungi can be destructive human pathogens responsible for various diseases in humans. Most people have a strong natural immunity against fungal infection. However, fungi can cause diseases when this immunity breaks down. In the last few years, fungal infection has increased strikingly and has been accompanied by a rise in the number of deaths of cancer patients, transplant recipients, and acquired immunodeficiency syndrome (AIDS) patients owing to fungal infections. The growth rate of fungi is very slow and quite difficult to identify. A series of molecules with antifungal activity against different strains of fungi have been found in insects, which can be of great importance to tackle human diseases. Insects secrete such compounds, which can be peptides, as a part of their immune defense reactions. Active antifungal peptides developed by insects to rapidly eliminate infectious pathogens are considered a component of the defense munitions. This review focuses on naturally occurring antifungal peptides from insects and their challenges to be used as armaments against human diseases.

  19. A novel peptide derived from human pancreatitis-associated protein inhibits inflammation in vivo and in vitro and blocks NF-kappa B signaling pathway.

    Directory of Open Access Journals (Sweden)

    Xiaolu Yang

    Full Text Available BACKGROUND: Pancreatitis-associated protein (PAP is a pancreatic secretory protein belongs to the group VII of C-type lectin family. Emerging evidence suggests that PAP plays a protective effect in inflammatory diseases. In the present study, we newly identified a 16-amino-acid peptide (named PAPep derived from C-type lectin-like domain (CTLD of human PAP with potent anti-inflammatory activity using both in vivo and in vitro assays. METHODOLOGY/PRINCIPAL FINDINGS: We assessed the anti-inflammatory effect of PAPep on endotoxin-induced uveitis (EIU in rats and demonstrated that intravitreal pretreatment of PAPep concentration-dependently attenuated clinical manifestation of EIU rats, reduced protein leakage and cell infiltration into the aqueous humor (AqH, suppressed tumor necrosis factor (TNF-α, interleukin (IL-6, intercellular adhesion molecule-1 (ICAM-1 and monocyte chemoattractant protein (MCP-1 production in ocular tissues, and improved histopathologic manifestation of EIU. Furthermore, PAPep suppressed the LPS-induced mRNA expression of TNF-α and IL-6 in RAW 264.7 cells, inhibited protein expression of ICAM-1 in TNF-α-stimulated human umbilical vein endothelial cells (HUVECs as well as U937 cells adhesion to HUVECs. Western blot analysis in ocular tissues and different cell lines revealed that the possible mechanism for this anti-inflammatory effect of PAPep may depend on its ability to inhibit the activation of NF-kB signaling pathway. CONCLUSIONS/SIGNIFICANCE: Our studies provide the first evidence that the sequence of PAPep is within the critically active region for the anti-inflammatory function of PAP and the peptide may be a promising candidate for the management of ocular inflammatory diseases.

  20. Cell adhesion in zebrafish embryos is modulated by March 8.

    Science.gov (United States)

    Kim, Mi Ha; Rebbert, Martha L; Ro, Hyunju; Won, Minho; Dawid, Igor B

    2014-01-01

    March 8 is a member of a family of transmembrane E3 ubiquitin ligases that have been studied mostly for their role in the immune system. We find that March 8 is expressed in the zebrafish egg and early embryo, suggesting a role in development. Both knock-down and overexpression of March 8 leads to abnormal development. The phenotype of zebrafish embryos and Xenopus animal explants overexpressing March 8 implicates impairment of cell adhesion as a cause of the effect. In zebrafish embryos and in cultured cells, overexpression of March 8 leads to a reduction in the surface levels of E-cadherin, a major cell-cell adhesion molecule. Experiments in cell culture further show that E-cadherin can be ubiquitinated by March 8. On the basis of these observations we suggest that March 8 functions in the embryo to modulate the strength of cell adhesion by regulating the localization of E-cadherin.

  1. Surface immobilization of fibronectin-derived PHSRN peptide on functionalized polymer films--effects on fibroblast spreading.

    Science.gov (United States)

    Satriano, Cristina; Messina, Grazia M L; Marino, Clara; Aiello, Ivana; Conte, Enrico; La Mendola, Diego; Distefano, Donatella A; D'Alessandro, Franca; Pappalardo, Giuseppe; Impellizzeri, Giuseppe

    2010-01-15

    The Pro-His-Ser-Arg-Asn (PHSRN) sequence in fibronectin is a second cell-binding site that synergistically affects Arg-Gly-Asp (RGD). The PHSRN peptide also induces cell invasion and accelerates wound healing. We report on the surface immobilization of PHSRN by spontaneous adsorption on polysiloxane thin films which have different surface free energy characteristics. Low-surface energy (hydrophobic) polysiloxane and the corresponding high-surface energy (hydrophilic) surfaces obtained by UV-ozone treatments were used as adsorbing substrates. The peptide adsorption process was investigated by quartz crystal microbalance with dissipation monitoring and atomic force microscopy. Both adsorption kinetics and peptide rearrangement dynamics at the solid interface were significantly different on the surface-modified films compared to the untreated ones. Fibroblast cells cultures at short times and in a simplified environment, i.e., a medium-free solution, were prepared to distinguish interaction events at the interface between cell membrane and surface-immobilized peptide for the two cases. It turned out that the cell-adhesive effect of immobilized PHSRN was different for hydrophobic compared to hydrophilic ones. Early signatures of cell spreading were only observed on the hydrophilic substrates. These effects are explained in terms of different spatial arrangements of PHSRN molecules immobilized on the two types of surfaces.

  2. Cooperative inhibitory effects of antisense oligonucleotide of cell adhesion molecules and cimetidine on cancer cell adhesion

    Institute of Scientific and Technical Information of China (English)

    Nan-Hong Tang; Yan-Ling Chen; Xiao-Qian Wang; Xiu-Jin Li; Feng-Zhi Yin; Xiao-Zhong Wang

    2004-01-01

    AIM: To explore the cooperative effects of antisense oligonucleotide (ASON) of cell adhesion molecules and cimetidine on the expression of E-selectin and ICAM-1 in endothelial cells and their adhesion to tumor cells.METHODS: After treatment of endothelial cells with ASON and/or cimetidine and induction with TNF-α, the protein and mRNA changes of E-selectin and ICAM-1 in endothelial cells were examined by flow cytometry and RT-PCR,respectively. The adhesion rates of endothelial cells to tumor cells were measured by cell adhesion experiment.RESULTS: In comparison with TNF-α inducing group, lipoASON and lipo-ASON/cimetidine could significantly decrease the protein and mRNA levels of E-selectin and ICAM-1 in endothelial cells, and lipo-ASON/cimetidine had most significant inhibitory effect on E-selectin expression (from 36.37±1.56% to 14.23±1.07%, P<0.001). Meanwhile,cimetidine alone could inhibit the expression of E-selectin (36.37±1.56% vs 27.2±1.31%, P<0.001), but not ICAM-1 (69.34±2.50% vs68.07±2.10%,P>O.05)and the two kinds of mRNA, either. Compared with TNF-αα inducing group, the rate of adhesion was markedly decreased in lipo-E-selectin ASON and lipo-E-selectin ASON/cimetidine treated groups(P<0.05),and Jipo-E-selectin ASON/cimetidine worked better than lipo-E-selectin ASON alone except for HepG2/ECV304 group(P<0.05). However, the decrease of adhesion was not significant in lipo-ICAM-1 ASON and lipo-ICAM-1 ASON/cimetidine treated groups except for HepG2/ECV304 group (P >0.05).CONCLUSION: These data demonstrate that ASON in combination with cimetidine in vitro can significantly reduce the adhesion between endothelial cells and hepatic or colorectal cancer cells, which is stronger than ASON or cimetidine alone. This study provides some useful proofs for gene therapy of antiadhesion.

  3. Patterned Poly(dopamine) Films for Enhanced Cell Adhesion.

    Science.gov (United States)

    Chen, Xi; Cortez-Jugo, Christina; Choi, Gwan H; Björnmalm, Mattias; Dai, Yunlu; Yoo, Pil J; Caruso, Frank

    2017-01-18

    Engineered materials that promote cell adhesion and cell growth are important in tissue engineering and regenerative medicine. In this work, we produced poly(dopamine) (PDA) films with engineered patterns for improved cell adhesion. The patterned films were synthesized via the polymerization of dopamine at the air-water interface of a floating bed of spherical particles. Subsequent dissolution of the particles yielded free-standing PDA films with tunable geometrical patterns. Our results show that these patterned PDA films significantly enhance the adhesion of both cancer cells and stem cells, thus showing promise as substrates for cell attachment for various biomedical applications.

  4. Patterned hybrid nanohole array surfaces for cell adhesion and migration.

    Science.gov (United States)

    Westcott, Nathan P; Lou, Yi; Muth, John F; Yousaf, Muhammad N

    2009-10-06

    We report the fabrication of hybrid nanohole array surfaces to study the role of the surface nanoevironment on cell adhesion and cell migration. We use polystyrene beads and reactive ion etching to control the size and the spacing between nanoholes on a tailored self-assembled monolayer inert gold surface. The arrays were characterized by scanning electron microscopy and brightfield microscopy. For cell adhesion studies, cells were seeded to these substrates to study the effect of ligand spacing on cell spreading, stress fiber formation, and focal adhesion structure and size. Finally, comparative cell migration rates were examined on the various nanohole array surfaces using time-lapse microscopy.

  5. Activation of Adhesion G Protein-coupled Receptors: AGONIST SPECIFICITY OF STACHEL SEQUENCE-DERIVED PEPTIDES.

    Science.gov (United States)

    Demberg, Lilian M; Winkler, Jana; Wilde, Caroline; Simon, Kay-Uwe; Schön, Julia; Rothemund, Sven; Schöneberg, Torsten; Prömel, Simone; Liebscher, Ines

    2017-03-17

    Members of the adhesion G protein-coupled receptor (aGPCR) family carry an agonistic sequence within their large ectodomains. Peptides derived from this region, called the Stachel sequence, can activate the respective receptor. As the conserved core region of the Stachel sequence is highly similar between aGPCRs, the agonist specificity of Stachel sequence-derived peptides was tested between family members using cell culture-based second messenger assays. Stachel peptides derived from aGPCRs of subfamily VI (GPR110/ADGRF1, GPR116/ADGRF5) and subfamily VIII (GPR64/ADGRG2, GPR126/ADGRG6) are able to activate more than one member of the respective subfamily supporting their evolutionary relationship and defining them as pharmacological receptor subtypes. Extended functional analyses of the Stachel sequences and derived peptides revealed agonist promiscuity, not only within, but also between aGPCR subfamilies. For example, the Stachel-derived peptide of GPR110 (subfamily VI) can activate GPR64 and GPR126 (both subfamily VIII). Our results indicate that key residues in the Stachel sequence are very similar between aGPCRs allowing for agonist promiscuity of several Stachel-derived peptides. Therefore, aGPCRs appear to be pharmacologically more closely related than previously thought. Our findings have direct implications for many aGPCR studies, as potential functional overlap has to be considered for in vitro and in vivo studies. However, it also offers the possibility of a broader use of more potent peptides when the original Stachel sequence is less effective. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  6. The antimicrobial peptides derived from chromogranin/secretogranin family, new actors of innate immunity.

    Science.gov (United States)

    Shooshtarizadeh, Peiman; Zhang, Dan; Chich, Jean-François; Gasnier, Claire; Schneider, Francis; Haïkel, Youssef; Aunis, Dominique; Metz-Boutigue, Marie-Hélène

    2010-11-30

    Chromogranins/secretogranins are members of the granin family present in secretory vesicles of nervous, endocrine and immune cells. In chromaffin cells, activation of nicotinic cholinergic receptors induces the release, with catecholamines, of bioactive peptides resulting from a natural processing. During the past decade, our laboratory has characterized new antimicrobial chromogranin-derived peptides in the secretions of stimulated bovine chromaffin cells. They act at the micromolar range against bacteria, fungi, yeasts, and are non-toxic for the mammalian cells. They are recovered in several biological fluids involved in defence mechanisms (human serum, neutrophil secretions and saliva). These new antimicrobial peptides demonstrate the major role of the adrenal medulla in innate immunity. In this review we focus on the antimicrobial peptides derived from human and bovine chromogranin A (CGA), chromogranin B (CGB) and secretogranin II (SGII) emphasizing their direct action against pathogens and their effects on immune cells.

  7. "Potential health benefits of lunasin: a multifaceted soy-derived bioactive peptide".

    Science.gov (United States)

    Lule, Vaibhao Kisanrao; Garg, Sheenam; Pophaly, Sarang Dilip; Hitesh; Tomar, Sudhir Kumar

    2015-03-01

    Bioactive peptides are small protein fragments derived from enzymatic hydrolysis of food proteins, fermentation with proteolytic starter cultures, and gastrointestinal digestion. These peptides have positive impacts on a number of physiological functions in living beings. Lunasin, a soy-derived bioactive peptide, is one of the most promising among them. Lunasin encoded within 2S albumin (GM2S-1) gene, identified as a novel peptide extracted from soybean seed. It is composed of 43 amino acid residues with a molecular weight of 5.5 kDa. Extensive scientific studies have shown that lunasin possesses inherent antioxidative, anti-inflammatory, anticancerous properties and could also play a vital role in regulating of cholesterol biosynthesis in the body. Its high bioavailability and heat stable nature allow its potential use as dietary supplement. The present review summarizes some of the potential health and therapeutic benefits of lunasin reported hitherto.

  8. Molecular Design, Structural Analysis and Antifungal Activity of Derivatives of Peptide CGA-N46.

    Science.gov (United States)

    Li, Rui-Fang; Lu, Zhi-Fang; Sun, Ya-Nan; Chen, Shi-Hua; Yi, Yan-Jie; Zhang, Hui-Ru; Yang, Shuo-Ye; Yu, Guang-Hai; Huang, Liang; Li, Chao-Nan

    2016-09-01

    Chromogranin A (CGA)-N46, a derived peptide of human chromogranin A, has antifungal activity. To further research the active domain of CGA-N46, a series of derivatives were designed by successively deleting amino acid from both terminus of CGA-N46, and the amino acid sequence of each derivative was analyzed by bioinformatic software. Based on the predicted physicochemical properties of the peptides, including half-life time in mammalian reticulocytes (in vitro), yeast (in vivo) and E. coli (in vivo), instability index, aliphatic index and grand average of hydropathicity (GRAVY), the secondary structure, net charge, the distribution of hydrophobic residues and hydrophilic residues, the final derivatives CGA-N15, CGA-N16, CGA-N12 and CGA-N8 were synthesized by solid-phase peptide synthesis. The results of bioinformatic analysis showed that CGA-N46 and its derivatives were α-helix, neutral or weak positive charge, hydrophilic, and CGA-N12 and CGA-N8 were more stable than the other derivatives. The results of circular dichroism confirmed that CGA-N46 and its derived peptides displayed α-helical structure in an aqueous solution and 30 mM sodium dodecylsulfate, but α-helical contents decreased in hydrophobic lipid vesicles. CGA-N15, CGA-N16, CGA-N12 and CGA-N8 had higher antifungal activities than their mother peptide CGA-N46. Among of the derived peptides, CGA-N12 showed the least hemolytic activity. In conclusion, we have successfully identified the active domain of CGA-N46 with strong antifungal activity and weak hemolytic activity, which provides the possibility to develop a new class of antibiotics.

  9. Improving surface functional properties of tofu whey-derived peptides by chemical modification with fatty acids.

    Science.gov (United States)

    Matemu, Athanasia Oswald; Katayama, Shigeru; Kayahara, Hisataka; Murasawa, Hisashi; Nakamura, Soichiro

    2012-04-01

    Effect of acylation with saturated fatty acids on surface functional properties of tofu whey-derived peptides was investigated. Tofu whey (TW) and soy proteins (7S, 11S, and acid-precipitated soy protein [APP]) were hydrolyzed by Protease M 'Amano' G, and resulting peptide mixtures were acylated with esterified fatty acids of different chain length (6C to 18C) to form a covalent linkage between the carboxyl group of fatty acid and the free amino groups of peptide. Acylation significantly (P whey ultra filtered fraction (UFTW proteins.

  10. Bioactive peptides derived from traditional Chinese medicine and traditional Chinese food: A review.

    Science.gov (United States)

    Liu, Ming; Wang, Yunpu; Liu, Yuhuan; Ruan, Roger

    2016-11-01

    There is an urgent treat of numerous chronic diseases including heart disease, stroke, cancer, chronic respiratory diseases and diabetes, which have a significant influence on the health of people worldwide. In addition to numerous preventive and therapeutic drug treatments, important advances have been achieved in the identification of bioactive peptides that may contribute to long-term health. Although bioactive peptides with various biological activities received unprecedented attention, as a new source of bioactive peptides, the significant role of bioactive peptides from traditional Chinese medicine and traditional Chinese food has not fully appreciated compared to other bioactive components. Hence, identification and bioactivity assessment of these peptides could benefit the pharmaceutical and food industry. Furthermore, the functional properties of bioactive peptides help to demystify drug properties and health benefits of traditional Chinese medicine and traditional Chinese food. This paper reviews the generation and biofunctional properties of various bioactive peptides derived from traditional Chinese medicine and traditional Chinese food. Mechanisms of digestion, bioavailability of bioactive peptides and interactions between traditional Chinese medicine and traditional Chinese food are also summarized in this review. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. A Review of Antioxidant Peptides Derived from Meat Muscle and By-Products

    Science.gov (United States)

    Liu, Rui; Xing, Lujuan; Fu, Qingquan; Zhou, Guang-hong; Zhang, Wan-gang

    2016-01-01

    Antioxidant peptides are gradually being accepted as food ingredients, supplemented in functional food and nutraceuticals, to positively regulate oxidative stress in the human body against lipid and protein oxidation. Meat muscle and meat by-products are rich sources of proteins and can be regarded as good materials for the production of bioactive peptides by use of enzymatic hydrolysis or direct solvent extraction. In recent years, there has been a growing number of studies conducted to characterize antioxidant peptides or hydrolysates derived from meat muscle and by-products as well as processed meat products, including dry-cured hams. Antioxidant peptides obtained from animal sources could exert not only nutritional value but also bioavailability to benefit human health. This paper reviews the antioxidant peptides or protein hydrolysates identified in muscle protein and by-products. We focus on the procedure for the generation of peptides with antioxidant capacity including the acquisition of crude peptides, the assessment of antioxidant activity, and the purification and identification of the active fraction. It remains critical to perform validation experiments with a cell model, animal model or clinical trial to eliminate safety concerns before final application in the food system. In addition, some of the common characteristics on structure-activity relationship are also reviewed based on the identified antioxidant peptides. PMID:27657142

  12. A Review of Antioxidant Peptides Derived from Meat Muscle and By-Products

    Directory of Open Access Journals (Sweden)

    Rui Liu

    2016-09-01

    Full Text Available Antioxidant peptides are gradually being accepted as food ingredients, supplemented in functional food and nutraceuticals, to positively regulate oxidative stress in the human body against lipid and protein oxidation. Meat muscle and meat by-products are rich sources of proteins and can be regarded as good materials for the production of bioactive peptides by use of enzymatic hydrolysis or direct solvent extraction. In recent years, there has been a growing number of studies conducted to characterize antioxidant peptides or hydrolysates derived from meat muscle and by-products as well as processed meat products, including dry-cured hams. Antioxidant peptides obtained from animal sources could exert not only nutritional value but also bioavailability to benefit human health. This paper reviews the antioxidant peptides or protein hydrolysates identified in muscle protein and by-products. We focus on the procedure for the generation of peptides with antioxidant capacity including the acquisition of crude peptides, the assessment of antioxidant activity, and the purification and identification of the active fraction. It remains critical to perform validation experiments with a cell model, animal model or clinical trial to eliminate safety concerns before final application in the food system. In addition, some of the common characteristics on structure-activity relationship are also reviewed based on the identified antioxidant peptides.

  13. Milk derived bioactive peptides and their impact on human health – A review

    Directory of Open Access Journals (Sweden)

    D.P. Mohanty

    2016-09-01

    Full Text Available Milk-derived bioactive peptides have been identified as potential ingredients of health-promoting functional foods. These bioactive peptides are targeted at diet-related chronic diseases especially the non-communicable diseases viz., obesity, cardiovascular diseases and diabetes. Peptides derived from the milk of cow, goat, sheep, buffalo and camel exert multifunctional properties, including anti-microbial, immune modulatory, anti-oxidant, inhibitory effect on enzymes, anti-thrombotic, and antagonistic activities against various toxic agents. Majority of those regulate immunological, gastrointestinal, hormonal and neurological responses, thereby playing a vital role in the prevention of cancer, osteoporosis, hypertension and other disorders as discussed in this review. For the commercial production of such novel bioactive peptides large scale technologies based on membrane separation and ion exchange chromatography methods have been developed. Separation and identification of those peptides and their pharmacodynamic parameters are necessary to transfer their potent functional properties into food applications. The present review summarizes the preliminary classes of bioactive milk-derived peptides along with their physiological functions, general characteristics and potential applications in health-care.

  14. Milk derived bioactive peptides and their impact on human health - A review.

    Science.gov (United States)

    Mohanty, D P; Mohapatra, S; Misra, S; Sahu, P S

    2016-09-01

    Milk-derived bioactive peptides have been identified as potential ingredients of health-promoting functional foods. These bioactive peptides are targeted at diet-related chronic diseases especially the non-communicable diseases viz., obesity, cardiovascular diseases and diabetes. Peptides derived from the milk of cow, goat, sheep, buffalo and camel exert multifunctional properties, including anti-microbial, immune modulatory, anti-oxidant, inhibitory effect on enzymes, anti-thrombotic, and antagonistic activities against various toxic agents. Majority of those regulate immunological, gastrointestinal, hormonal and neurological responses, thereby playing a vital role in the prevention of cancer, osteoporosis, hypertension and other disorders as discussed in this review. For the commercial production of such novel bioactive peptides large scale technologies based on membrane separation and ion exchange chromatography methods have been developed. Separation and identification of those peptides and their pharmacodynamic parameters are necessary to transfer their potent functional properties into food applications. The present review summarizes the preliminary classes of bioactive milk-derived peptides along with their physiological functions, general characteristics and potential applications in health-care.

  15. Treatment of Experimental Brain Tumors with Trombospondin-1 Derived Peptides: an In Vivo Imaging Study

    Directory of Open Access Journals (Sweden)

    A. Bogdanov, Jr.

    1999-11-01

    Full Text Available Antiangiogenic and antiproliferative effects of synthetic D-reverse peptides derived from the type 1 repeats of thrombospondin (TSP1 [1,2] were studied in rodent C6 glioma and 9L gliosarcomas. To directly measure tumor size and vascular parameters, we employed in vivo magnetic resonance (MR imaging and corroborated results by traditional morphometric tissue analysis. Rats bearing either C6 or 9L tumors were treated with TSP1-derived peptide (D-reverse amKRFKQDGGWSHWSPWSSac, n=13 or a control peptide (D-reverse am KRAKQAGGASHASPASSac, n=12 at 10 mg/kg, administered either intravenously or through subcutaneous miniosmotic pumps starting 10 days after tumor implantation. Eleven days later, the effect of peptide treatment was evaluated. TSP1 peptide-treated 9L tumors (50.7±44.2 mm3, n=7 and C6 tumors (41.3±34.2 mm3, n=6 were significantly smaller than tumors treated with control peptide (9L: 215.7±67.8 mm3, n=6; C6:184.2±105.2 mm3, n=6. In contrast, the in vivo vascular volume fraction, the mean vascular area (determined by microscopy, and the microvascular density of tumors were not significantly different in any of the experimental groups. In cell culture, TSP1, and the amKRFKQDGGWSHWSPWSSac peptide showed antiproliferative effects against C6 with an IC of 45 nM for TSP1. These results indicate that TSP1derived peptides retard brain tumor growth presumably as a result of slower de novo blood vessel formation and synergistic direct antiproliferative effects on tumor cells. We also show that in vivo MR imaging can be used to assess treatment efficacy of novel antiangiogenic drugs non-invasively, which has obvious implications for clinical trials.

  16. Structural characteristics and antiviral activity of multiple peptides derived from MDV glycoproteins B and H

    Directory of Open Access Journals (Sweden)

    Wang Ming

    2011-04-01

    Full Text Available Abstract Background Marek's disease virus (MDV, which is widely considered to be a natural model of virus-induced lymphoma, has the potential to cause tremendous losses in the poultry industry. To investigate the structural basis of MDV membrane fusion and to identify new viral targets for inhibition, we examined the domains of the MDV glycoproteins gH and gB. Results Four peptides derived from the MDV glycoprotein gH (gHH1, gHH2, gHH3, and gHH5 and one peptide derived from gB (gBH1 could efficiently inhibit plaque formation in primary chicken embryo fibroblast cells (CEFs with 50% inhibitory concentrations (IC50 of below 12 μM. These peptides were also significantly able to reduce lesion formation on chorioallantoic membranes (CAMs of infected chicken embryos at a concentration of 0.5 mM in 60 μl of solution. The HR2 peptide from Newcastle disease virus (NDVHR2 exerted effects on MDV specifically at the stage of virus entry (i.e., in a cell pre-treatment assay and an embryo co-treatment assay, suggesting cross-inhibitory effects of NDV HR2 on MDV infection. None of the peptides exhibited cytotoxic effects at the concentrations tested. Structural characteristics of the five peptides were examined further. Conclusions The five MDV-derived peptides demonstrated potent antiviral activity, not only in plaque formation assays in vitro, but also in lesion formation assays in vivo. The present study examining the antiviral activity of these MDV peptides, which are useful as small-molecule antiviral inhibitors, provides information about the MDV entry mechanism.

  17. Quantifying Cell Adhesion through Impingement of a Controlled Microjet

    NARCIS (Netherlands)

    Visser, Claas Willem; Gielen, Marise V.; Hao, Zhenxia; Gac, Le Severine; Lohse, Detlef; Sun, Chao

    2015-01-01

    The impingement of a submerged, liquid jet onto a cell-covered surface allows assessing cell attachment on surfaces in a straightforward and quantitative manner and in real time, yielding valuable information on cell adhesion. However, this approach is insufficiently characterized for reliable and r

  18. The FRIABLE1 gene product affects cell adhesion in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Lutz Neumetzler

    Full Text Available Cell adhesion in plants is mediated predominantly by pectins, a group of complex cell wall associated polysaccharides. An Arabidopsis mutant, friable1 (frb1, was identified through a screen of T-DNA insertion lines that exhibited defective cell adhesion. Interestingly, the frb1 plants displayed both cell and organ dissociations and also ectopic defects in organ separation. The FRB1 gene encodes a Golgi-localized, plant specific protein with only weak sequence similarities to known proteins (DUF246. Unlike other cell adhesion deficient mutants, frb1 mutants do not have reduced levels of adhesion related cell wall polymers, such as pectins. Instead, FRB1 affects the abundance of galactose- and arabinose-containing oligosaccharides in the Golgi. Furthermore, frb1 mutants displayed alteration in pectin methylesterification, cell wall associated extensins and xyloglucan microstructure. We propose that abnormal FRB1 action has pleiotropic consequences on wall architecture, affecting both the extensin and pectin matrices, with consequent changes to the biomechanical properties of the wall and middle lamella, thereby influencing cell-cell adhesion.

  19. Spatially controlled cell adhesion on three-dimensional substrates

    NARCIS (Netherlands)

    Richter, Christine; Reinhardt, Martina; Giselbrecht, Stefan; Leisen, Daniel; Trouillet, Vanessa; Truckenmüller, Roman; Blau, Axel; Ziegler, Christiane; Welle, Alexander

    2010-01-01

    The microenvironment of cells in vivo is defined by spatiotemporal patterns of chemical and biophysical cues. Therefore, one important goal of tissue engineering is the generation of scaffolds with defined biofunctionalization in order to control processes like cell adhesion and differentiation. Mim

  20. Repetitive Arg-Gly-Asp peptide as a cell-stimulating agent on electrospun poly(ϵ-caprolactone) scaffold for tissue engineering.

    Science.gov (United States)

    Chaisri, Pacharaporn; Chingsungnoen, Artit; Siri, Sineenat

    2013-11-01

    Electrospun scaffolds derived from poly(ϵ-caprolactone) (PCL), a well known biodegradable material, have an architecture that is suitable for hosting cells. However, their biomedical applications are restricted because these scaffolds lack the bioactivity necessary to stimulate cell responses. In this work, a repetitive Arg-Gly-Asp (rRGD) peptide was produced as a cell-stimulating agent to provide the PCL scaffold with bioactivity. DNA encoding rRGD was amplified by polymerase chain reaction using overlap primers without a DNA template, and cloned into a protein expression vector to produce a His-tag fusion peptide. In an in vitro cell adhesion assay, the purified rRGD peptide, comprising 30 RGD repeats, promoted a 1.5-fold greater cell adhesion than the commercial tripeptide RGD. The rRGD peptide was immobilized onto an electrospun PCL scaffold that had been pretreated with argon plasma and graft-polymerized with acrylic acid. Fourier transform infrared (FTIR) analysis indicated that covalently linked rRGD peptide was present on the scaffold. The PCL scaffold with immobilized rRGD showed significantly changed hydrophilic properties and an enhanced adhesion and proliferation of mouse fibroblast cells by 2.3- and 2.9-fold, respectively, compared to the PCL scaffold alone. Through its ability to promote cell adhesion and proliferation, the rRGD peptide has great potential as a stimulant for improving the suboptimal cell-matrix interaction of polymeric scaffolds for tissue engineering applications.

  1. Food-derived opioid peptides inhibit cysteine uptake with redox and epigenetic consequences.

    Science.gov (United States)

    Trivedi, Malav S; Shah, Jayni S; Al-Mughairy, Sara; Hodgson, Nathaniel W; Simms, Benjamin; Trooskens, Geert A; Van Criekinge, Wim; Deth, Richard C

    2014-10-01

    Dietary interventions like gluten-free and casein-free diets have been reported to improve intestinal, autoimmune and neurological symptoms in patients with a variety of conditions; however, the underlying mechanism of benefit for such diets remains unclear. Epigenetic programming, including CpG methylation and histone modifications, occurring during early postnatal development can influence the risk of disease in later life, and such programming may be modulated by nutritional factors such as milk and wheat, especially during the transition from a solely milk-based diet to one that includes other forms of nutrition. The hydrolytic digestion of casein (a major milk protein) and gliadin (a wheat-derived protein) releases peptides with opioid activity, and in the present study, we demonstrate that these food-derived proline-rich opioid peptides modulate cysteine uptake in cultured human neuronal and gastrointestinal (GI) epithelial cells via activation of opioid receptors. Decreases in cysteine uptake were associated with changes in the intracellular antioxidant glutathione and the methyl donor S-adenosylmethionine. Bovine and human casein-derived opioid peptides increased genome-wide DNA methylation in the transcription start site region with a potency order similar to their inhibition of cysteine uptake. Altered expression of genes involved in redox and methylation homeostasis was also observed. These results illustrate the potential of milk- and wheat-derived peptides to exert antioxidant and epigenetic changes that may be particularly important during the postnatal transition from placental to GI nutrition. Differences between peptides derived from human and bovine milk may contribute to developmental differences between breastfed and formula-fed infants. Restricted antioxidant capacity, caused by wheat- and milk-derived opioid peptides, may predispose susceptible individuals to inflammation and systemic oxidation, partly explaining the benefits of gluten-free or

  2. Screening of soy protein-derived hypotriglyceridemic di-peptides in vitro and in vivo

    Directory of Open Access Journals (Sweden)

    Matsui Toshiro

    2011-05-01

    Full Text Available Abstract Background Soy protein and soy peptides have attracted considerable attention because of their potentially beneficial biological properties, including antihypertensive, anticarcinogenic, and hypolipidemic effects. Although soy protein isolate contains several bioactive peptides that have distinct physiological activities in lipid metabolism, it is not clear which peptide sequences are responsible for the triglyceride (TG-lowering effects. In the present study, we investigated the effects of soy protein-derived peptides on lipid metabolism, especially TG metabolism, in HepG2 cells and obese Otsuka Long-Evans Tokushima fatty (OLETF rats. Results In the first experiment, we found that soy crude peptide (SCP-LD3, which was prepared by hydrolyze of soy protein isolate with endo-type protease, showed hypolipidemic effects in HepG2 cells and OLETF rats. In the second experiment, we found that hydrophilic fraction, separated from SCP-LD3 with hydrophobic synthetic absorbent, revealed lipid-lowering effects in HepG2 cells and OLETF rats. In the third experiment, we found that Fraction-C (Frc-C peptides, fractionated from hydrophilic peptides by gel permeation chromatography-high performance liquid chromatography, significantly reduced TG synthesis and apolipoprotein B (apoB secretion in HepG2 cells. In the fourth experiment, we found that the fraction with 0.1% trifluoroacetic acid, isolated from Frc-C peptides by octadecylsilyl column chromatography, showed hypolipidemic effects in HepG2 cells. In the final experiment, we found that 3 di-peptides, Lys-Ala, Val-Lys, and Ser-Tyr, reduced TG synthesis, and Ser-Tyr additionally reduced apoB secretion in HepG2 cells. Conclusion Novel active peptides with TG-lowering effects from soy protein have been isolated.

  3. δ-Peptides from RuAAC-Derived 1,5-Disubstituted Triazole Units

    KAUST Repository

    Johansson, Johan R.

    2014-02-14

    Non-natural peptides with structures and functions similar to natural peptides have emerged lately in biomedical as well as nanotechnological contexts. They are interesting for pharmaceutical applications since they can adopt structures with new targeting potentials and because they are generally not prone to degradation by proteases. We report here a new set of peptidomimetics derived from δ-peptides, consisting of n units of a 1,5-disubstituted 1,2,3-triazole amino acid (5Tzl). The monomer was prepared using ruthenium-catalyzed azide-alkyne cycloaddition (RuAAC) chemistry using [RuCl2Cp]x as the catalyst, allowing for simpler purification and resulting in excellent yields. This achiral monomer was used to prepare peptide oligomers that are water soluble independent of peptide chain length. Conformational analysis and structural investigations of the oligomers were performed by 2D NOESY NMR experiments, and by quantum chemical calculations using the ωB97X-D functional. These data indicate that several conformations may co-exist with slight energetic differences. Together with their increased hydrophilicity, this feature of homo-5Tzl may prove essential for mimicking natural peptides composed of α-amino acids, where the various secondary structures are achieved by side chain effects and not by the rigidity of the peptide backbone. The improved synthetic method allows for facile variation of the 5Tzl amino acid side chains, further increasing the versatility of these compounds. A new set of non-natural peptides composed of 1,5-disubstituted 1,2,3-triazole amino acids is presented. These peptides benefit from: a) modular synthesis of the monomers, allowing variation of the side chains; b) increased solubility of the oligomers in water, irrespective of peptide length; c) flexibility of the backbone allowing these foldamers to adopt several conformations. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Effects of ethanol and NAP on cerebellar expression of the neural cell adhesion molecule L1.

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    Devon M Fitzgerald

    Full Text Available The neural cell adhesion molecule L1 is critical for brain development and plays a role in learning and memory in the adult. Ethanol inhibits L1-mediated cell adhesion and neurite outgrowth in cerebellar granule neurons (CGNs, and these actions might underlie the cerebellar dysmorphology of fetal alcohol spectrum disorders. The peptide NAP potently blocks ethanol inhibition of L1 adhesion and prevents ethanol teratogenesis. We used quantitative RT-PCR and Western blotting of extracts of cerebellar slices, CGNs, and astrocytes from postnatal day 7 (PD7 rats to investigate whether ethanol and NAP act in part by regulating the expression of L1. Treatment of cerebellar slices with 20 mM ethanol, 10(-12 M NAP, or both for 4 hours, 24 hours, and 10 days did not significantly affect L1 mRNA and protein levels. Similar treatment for 4 or 24 hours did not regulate L1 expression in primary cultures of CGNs and astrocytes, the predominant cerebellar cell types. Because ethanol also damages the adult cerebellum, we studied the effects of chronic ethanol exposure in adult rats. One year of binge drinking did not alter L1 gene and protein expression in extracts from whole cerebellum. Thus, ethanol does not alter L1 expression in the developing or adult cerebellum; more likely, ethanol disrupts L1 function by modifying its conformation and signaling. Likewise, NAP antagonizes the actions of ethanol without altering L1 expression.

  5. Identification and design of p53-derived HLA-A2-binding peptides with increased CTL immunogenicity

    DEFF Research Database (Denmark)

    Petersen, T R; Buus, S; Brunak, S;

    2001-01-01

    of peptide binding to HLA-A2 molecules, we identified three p53 protein-derived nonamer peptides with intermediate binding owing to suboptimal amino acids in the P2 anchor position. These peptides were synthesized along with the corresponding analogs, where the natural P2 residue had been replaced...

  6. Identification of MHC class I H-2 Kb/Db-restricted immunogenic peptides derived from retinal proteins

    DEFF Research Database (Denmark)

    Wang, Mingjun; Bai, Fang; Pries, Mette

    2006-01-01

    . The immunogenic peptides alone did not induce inflammation in the eyes, but they could enhance severity of uveitis induced by IRBP. CONCLUSIONS: Five of 21 H-2 Kb/Db-binding retinal protein-derived peptides were found to be immunogenic, suggesting that these peptides could function as autoantigenic epitopes...... in the development of inflammatory eye diseases, such as uveitis....

  7. Translational medicine in fish-derived peptides: from fish endocrinology to human physiology and diseases.

    Science.gov (United States)

    Takahashi, Kazuhiro

    2004-02-01

    Recent studies have revealed the importance of fish-derived peptide hormones to human endocrinology. These peptides include melanin-concentrating hormone (MCH), urocortins (human urotensin-I), and urotensin-II. MCH, a hypothalamic peptide, is a potent stimulator on appetite. Urocortins, e.g. urocortin 1 and urocortin 3 (stresscopin), are endogenous ligands for the corticotropin-releasing factor (CRF) receptors, particularly CRF type 2 receptor, that mediates a vasodilator action, a positive inotropic action and a central appetite-inhibiting action. These actions mediated by CRF type 2 receptor may ameliorate the stress response. Human urotensin-II is a potent vasoconstrictor peptide, while it acts as a vasodilator on some arteries. Human urotensin-II is expressed in various types of cells and tissues, including cardiovascular tissues, as well as many types of tumor cells. Thus, these fish-derived peptides appear to play important roles in human physiology, such as appetite regulation, stress response and cardiovascular regulation, and also in diseases, for example, obesity, cardiovascular diseases and tumors. Development of antagonists/agonists against the receptors for these peptides may open new strategies for the treatment of various diseases, including obesity-related diseases, hypertension, heart failure and malignant tumors.

  8. Immunogenicity of HLA Class I and II Double Restricted Influenza A-Derived Peptides

    DEFF Research Database (Denmark)

    Pedersen, Sara Ram; Christensen, Jan Pravsgaard; Buus, Søren;

    2016-01-01

    The aim of the present study was to identify influenza A-derived peptides which bind to both HLA class I and -II molecules and by immunization lead to both HLA class I and class II restricted immune responses. Eight influenza A-derived 9-11mer peptides with simultaneous binding to both HLA-A*02......:01 and HLA-DRB1*01:01 molecules were identified by bioinformatics and biochemical technology. Immunization of transgenic HLA-A*02:01/HLA-DRB1*01:01 mice with four of these double binding peptides gave rise to both HLA class I and class II restricted responses by CD8 and CD4 T cells, respectively, whereas...... with this, peptide vaccination did not decrease virus titres in the lungs of intranasally influenza challenged mice. Our data show that HLA class I and class II double binding peptides can be identified by bioinformatics and biochemical technology. By immunization, double binding peptides can give rise...

  9. Iodinated derivatives of vasoactive intestinal peptide (VIP), PHI and PHM: purification, chemical characterization and biological activity

    Energy Technology Data Exchange (ETDEWEB)

    McMaster, D.; Suzuki, Y.; Rorstad, O.; Lederis, K.

    1987-07-01

    The iodination of vasoactive intestinal peptide (VIP) was studied, using a variety of enzymatic and chemical iodination methods. Reversed phase high performance liquid chromatography (HPLC) was used to purify the reaction products. The lactoperoxidase-glucose oxidase method gave excellent results in terms of reproducibility, iodine incorporation, and yield of the non-oxidized products (Tyr(I)10)VIP and (Tyr(I)22)VIP, and was used to prepare both /sup 125/I and /sup 127/I labelled derivatives. In both cases, direct application to HPLC and a single column system were used. Although the oxidized peptides (Tyr(I)10,Met(O)17)VIP and (Tyr(I)22,Met(O)17)VIP could be generated to varying degrees directly by iodination of VIP, these were most conveniently prepared by iodination of (Met(O)17)VIP. Iodinated derivatives of the homologous peptides PHI and PHM were likewise prepared by rapid, one-step HPLC procedures. The site and degree of iodination were determined by HPLC peptide mapping of tryptic digests and amino acid analyses, and in the case of (Tyr(I)10)VIP also by sequencing. The vasorelaxant activities of the iodinated peptides in bovine cerebral artery preparations did not differ significantly from those of the corresponding noniodinated peptides, with the exception of (Tyr(I)10,Met(O)17)VIP and (Tyr(I)22,Met(O)17)VIP which, unlike (Met(O)17)VIP itself, had slightly lower potency than VIP.

  10. Alpha-amidated peptides derived from pro-opiomelanocortin in human pituitary tumours

    DEFF Research Database (Denmark)

    Fenger, M; Johnsen, A H

    1988-01-01

    Human pituitary tumours, obtained at surgery for Cushing's disease and Nelson's syndrome, were extracted and the content and molecular forms of pro-opiomelanocortin (POMC)-derived peptides determined by radioimmunoassay, gel chromatography, reversed-phase high-performance liquid chromatography....... In conclusion, all the molecular forms of the amidated peptides detected in tumours from patients with Cushing's disease and Nelson's syndrome were similar to the molecular forms found in the normal human pituitary. The main difference between the tumours and the normal pituitary was the greater amount...... (HPLC) and sequence analysis. In the tumours from patients with Cushing's disease the mean concentrations of amidated peptides relative to the total amount of POMC were as follows: alpha-MSH, 1.7%; amidated gamma-MSH (gamma 1-MSH), 8.5% and the peptide linking gamma-MSH and ACTH in the precursor (hinge...

  11. Syntenin-1 and ezrin proteins link activated leukocyte cell adhesion molecule to the actin cytoskeleton

    NARCIS (Netherlands)

    Tudor, C.; Riet, J. te; Eich, C.; Harkes, R.; Smisdom, N.; Bouhuijzen-Wenger, J.; Ameloot, M.; Holt, M.; Kanger, J.S.; Figdor, C.G.; Cambi, A.; Subramaniam, V.

    2014-01-01

    Activated leukocyte cell adhesion molecule (ALCAM) is a type I transmembrane protein member of the immunoglobulin superfamily of cell adhesion molecules. Involved in important pathophysiological processes such as the immune response, cancer metastasis, and neuronal development, ALCAM undergoes both

  12. Active Peptide-Conjugated Chitosan Matrices as an Artificial Basement Membrane

    Directory of Open Access Journals (Sweden)

    Kentaro Hozumi

    2015-02-01

    Full Text Available The basement membrane, a thin extracellular matrix, plays a critical role in tissue development and repair. Laminins are the major component of basement membrane and have diverse biological activities. We have identified various cell-adhesive peptides from laminins and their specific cell surface receptors. Polysaccharides, including chitosan, have been used as scaffolds, which regulate cellular functions for tissue engineering. We have developed laminin-derived active peptide-chitosan matrices as functional scaffolds. The biological activity of the peptides was enhanced when the peptides were conjugated to a chitosan matrix, suggesting that the peptide-chitosan matrix approach has an advantage for an active biomaterial. Further, the laminin peptide-chitosan matrices have the potential to mimic the basement membrane and are useful for tissue engineering as an artificial basement membrane.

  13. Antimicrobial properties of two novel peptides derived from Theobroma cacao osmotin.

    Science.gov (United States)

    Falcao, Loeni L; Silva-Werneck, Joseilde O; Ramos, Alessandra de R; Martins, Natalia F; Bresso, Emmanuel; Rodrigues, Magali A; Bemquerer, Marcelo P; Marcellino, Lucilia H

    2016-05-01

    The osmotin proteins of several plants display antifungal activity, which can play an important role in plant defense against diseases. Thus, this protein can be useful as a source for biotechnological strategies aiming to combat fungal diseases. In this work, we analyzed the antifungal activity of a cacao osmotin-like protein (TcOsm1) and of two osmotin-derived synthetic peptides with antimicrobial features, differing by five amino acids residues at the N-terminus. Antimicrobial tests showed that TcOsm1 expressed in Escherichia coli inhibits the growth of Moniliophthora perniciosa mycelium and Pichia pastoris X-33 in vitro. The TcOsm1-derived peptides, named Osm-pepA (H-RRLDRGGVWNLNVNPGTTGARVWARTK-NH2), located at R23-K49, and Osm-pepB (H-GGVWNLNVNPGTTGARVWARTK-NH2), located at G28-K49, inhibited growth of yeasts (Saccharomyces cerevisiae S288C and Pichia pastoris X-33) and spore germination of the phytopathogenic fungi Fusarium f. sp. glycines and Colletotrichum gossypi. Osm-pepA was more efficient than Osm-pepB for S. cerevisiae (MIC=40μM and MIC=127μM, respectively), as well as for P. pastoris (MIC=20μM and MIC=127μM, respectively). Furthermore, the peptides presented a biphasic performance, promoting S. cerevisiae growth in doses around 5μM and inhibiting it at higher doses. The structural model for these peptides showed that the five amino acids residues, RRLDR at Osm-pepA N-terminus, significantly affect the tertiary structure, indicating that this structure is important for the peptide antimicrobial potency. This is the first report of development of antimicrobial peptides from T. cacao. Taken together, the results indicate that the cacao osmotin and its derived peptides, herein studied, are good candidates for developing biotechnological tools aiming to control phytopathogenic fungi. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. The Neural Cell Adhesion Molecule NCAM2/OCAM/RNCAM, a Close Relative to NCAM

    DEFF Research Database (Denmark)

    Kulahin, Nikolaj; Walmod, Peter

    2008-01-01

    Cell adhesion molecules (CAMs) constitute a large class of plasma membrane-anchored proteins that mediate attachment between neighboring cells and between cells and the surrounding extracellular matrix (ECM). However, CAMs are more than simple mediators of cell adhesion. The neural cell adhesion ...

  15. Heterogeneity of glucagonomas due to differential processing of proglucagon-derived peptides

    DEFF Research Database (Denmark)

    Challis, Benjamin G; Albrechtsen, Nicolai J Wewer; Bansiya, Vishakha;

    2015-01-01

    UNLABELLED: Pancreatic neuroendocrine tumours (pNETs) secreting proglucagon are associated with phenotypic heterogeneity. Here, we describe two patients with pNETs and varied clinical phenotypes due to differential processing and secretion of proglucagon-derived peptides (PGDPs). Case 1, a 57-yea...

  16. Experimental Research on Ectopic Osteogenesis of BMP2-derived Peptide P24 Combined with PLGA Copolymers

    Institute of Scientific and Technical Information of China (English)

    DUAN Zhixia; ZHENG Qixin; GUO Xiaodong; YUAN Quan; CHEN Shunguang

    2007-01-01

    To experimentally evaluate the ectopic osteogenetic capacity of synthesized BMP2-derived peptide P24 combined with poly lactic-co-glycolic acid (PLGA), Wistar rats were divided into two groups: group A, in which BMP2-derived peptide P24/PLGA complex was implanted,and group B which received simple PLGA implant. The complex was respectively implanted into the back muscles of rats. Samples were taken the 1 st, 4 th, 8 th, and the 12 th week after the implantation.Their bone formation was detected by X-ray examination, and tissue response was histologically observed. Western blotting was used for the detection of the expression of collagen Ⅰ (Col- Ⅰ ) and osteopontin (OPN). There was acute inflammation in the tissue around both types of implants at early stage. The cartilage was found around implant areas 4 weeks after the implantation of BMP2-derived peptide p24/PLGA complex, 8 weeks after the implantation, osteoblasts were found, and 12 weeks after the implantation, typical trabecular bone structure was observed. In group B, after 12 weeks, no osteoblasts were found. It is concluded that PLGA is an ideal scaffold material for bone tissue engineering. BMP2-derived peptide can start endochondral ossification and is more effective in inducing ectopic osteogenesis.

  17. Two Polymorphisms in the Epithelial Cell-Derived Neutrophil-Activating Peptide (ENA-78 Gene

    Directory of Open Access Journals (Sweden)

    Mahsa M. Amoli

    2005-01-01

    Full Text Available Increased expression of epithelial cell-derived neutrophil-activating peptide (ENA-78 has been reported in several immune and inflammatory conditions suggesting its role in inflammatory response. We have identified two single nucleotide polymorphisms in the promoter and exon 2 of the ENA-78 gene by scanning the full length gene using DHPLC DNA fragment analysis and DNA sequencing.

  18. Synthesis and evaluation of phenylalanine-derived trifluoromethyl ketones for peptide-based oxidation catalysis.

    Science.gov (United States)

    Featherston, Aaron L; Miller, Scott J

    2016-10-15

    We report the synthesis of phenylalanine-derived trifluoromethyl ketones for the in situ generation of dioxiranes for the purpose of oxidation catalysis. The key features of this synthesis include the use of a masked ketone strategy and a Negishi cross-coupling to access the parent amino acid. The derivatives can be readily incorporated into a peptide for use in oxidation chemistry and exhibit good stability and reactivity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. In vivo tumor cell adhesion in the pulmonary microvasculature is exclusively mediated by tumor cell - endothelial cell interaction

    Directory of Open Access Journals (Sweden)

    Mees Soeren T

    2010-04-01

    Full Text Available Abstract Background Metastasis formation is the leading cause of death among colon cancer patients. We established a new in-situ model of in vivo microscopy of the lung to analyse initiating events of metastatic tumor cell adhesion within this typical metastatic target of colon cancer. Methods Anaesthetized CD rats were mechanically ventilated and 106 human HT-29LMM and T84 colon cancer cells were injected intracardially as single cell suspensions. Quantitative in vivo microscopy of the lung was performed in 10 minute intervals for a total of 40 minutes beginning with the time of injection. Results After vehicle treatment of HT-29LMM controls 15.2 ± 5.3; 14.2 ± 7.5; 11.4 ± 5.5; and 15.4 ± 6.5 cells/20 microscopic fields were found adherent within the pulmonary microvasculature in each 10 minute interval. Similar numbers were found after injection of the lung metastasis derived T84 cell line and after treatment of HT-29LMM with unspecific mouse control-IgG. Subsequently, HT-29LMM cells were treated with function blocking antibodies against β1-, β4-, and αv-integrins wich also did not impair tumor cell adhesion in the lung. In contrast, after hydrolization of sialylated glycoproteins on the cells' surface by neuraminidase, we observed impairment of tumor cell adhesion by more than 50% (p Conclusions These results demonstrate that the initial colon cancer cell adhesion in the capillaries of the lung is predominantly mediated by tumor cell - endothelial cell interactions, possibly supported by platelets. In contrast to reports of earlier studies that metastatic tumor cell adhesion occurs through integrin mediated binding of extracellular matrix proteins in liver, in the lung, the continuously lined endothelium appears to be specifically targeted by circulating tumor cells.

  20. Inhibition of HIV-1 infection by synthetic peptides derived CCR5 fragments.

    Science.gov (United States)

    Imai, Masaki; Baranyi, Lajos; Okada, Noriko; Okada, Hidechika

    2007-02-23

    HIV-1 infection requires interaction of viral envelope protein gp160 with CD4 and a chemokine receptor, CCR5 or CXCR4 as entry coreceptor. We designed HIV-inhibitory peptides targeted to CCR5 using a novel computer program (ANTIS), which searched all possible sense-antisense amino acid pairs between proteins. Seven AHBs were found in CCR5 receptor. All AHB peptides were synthesized and tested for their ability to prevent HIV-1 infection to human T cells. A peptide fragment (LC5) which is a part of the CCR5 receptor corresponding to the loop between the fifth and sixth transmembrane regions (amino acids 222-240) proved to inhibit HIV-1IIIB infection of MT-4 cells. Interaction of these antisense peptides could be involved in sustaining HIV-1 infectivity. LC5 effectively indicated dose-dependent manner, and the suppression was enhanced additively by T20 peptide, which inhibits infection in vitro by disrupting the gp41 conformational changes necessary for membrane fusion. Thus, these results indicate that CCR5-derived AHB peptides could provide a useful tool to define the mechanism(s) of HIV infection, and may provide insight which will contribute to the development of an anti-HIV-1 reagent.

  1. Proglucagon-Derived Peptides Do Not Significantly Affect Acute Exocrine Pancreas in Rats.

    Science.gov (United States)

    Akalestou, Elina; Christakis, Ioannis; Solomou, Antonia M; Minnion, James S; Rutter, Guy A; Bloom, Stephen R

    2016-08-01

    Reports have suggested a link between treatment with glucagon-like peptide 1 (GLP-1) analogs and an increased risk of pancreatitis. Oxyntomodulin, a dual agonist of both GLP-1 and glucagon receptors, is currently being investigated as a potential antiobesity therapy, but little is known about its pancreatic safety. The aim of the study was to investigate the acute effect of oxyntomodulin and other proglucagon-derived peptides on the rat exocrine pancreas. Glucagon-like peptide 1, oxyntomodulin, glucagon, and exendin-4 were infused into anesthetized rats to measure plasma amylase concentration changes. In addition, the effect of each peptide on both amylase release and proliferation in rat pancreatic acinar (AR42J) and primary isolated ductal cells was determined. Plasma amylase did not increase postpeptide infusion, compared with vehicle and cholecystokinin; however, oxyntomodulin inhibited plasma amylase when coadministered with cholecystokinin. None of the peptides caused a significant increase in proliferation rate or amylase secretion from acinar and ductal cells. The investigated peptides do not have an acute effect on the exocrine pancreas with regard to proliferation and plasma amylase, when administered individually. Oxyntomodulin seems to be a potent inhibitor of amylase release, potentially making it a safer antiobesity agent regarding pancreatitis, compared with GLP-1 agonists.

  2. Interaction of 18-residue peptides derived from amphipathic helical segments of globular proteins with model membranes

    Indian Academy of Sciences (India)

    Chandrasekaran Sivakamasundari; Ramakrishnan Nagaraj

    2009-06-01

    We investigated the interaction of six 18-residue peptides derived from amphipathic helical segments of globular proteins with model membranes. The net charge of the peptides at neutral pH varies from –1 to +6. Circular dichroism spectra indicate that peptides with a high net positive charge tend to fold into a helical conformation in the presence of negatively charged lipid vesicles. In helical conformation, their average hydrophobic moment and hydrophobicity would render them surface-active. The composition of amino acids on the polar face of the helix in the peptides is considerably different. The peptides show variations in their ability to permeabilise zwitterionic and anionic lipid vesicles. Whereas increased net positive charge favours greater permeabilisation, the distribution of charged residues in the polar face also plays a role in determining membrane activity. The distribution of amino acids in the polar face of the helix in the peptides that were investigated do not fall into the canonical classes described. Amphipathic helices, which are part of proteins, with a pattern of amino acid distribution different from those observed in class L, A and others, could help in providing newer insights into peptide–membrane interactions.

  3. The VGF-derived peptide TLQP-62 modulates insulin secretion and glucose homeostasis.

    Science.gov (United States)

    Petrocchi-Passeri, Pamela; Cero, Cheryl; Cutarelli, Alessandro; Frank, Claudio; Severini, Cinzia; Bartolomucci, Alessandro; Possenti, Roberta

    2015-06-01

    Insulin secretion control is critical for glucose homeostasis. Paracrine and autocrine molecules secreted by cells of the islet of Langerhans, as well as by intramural and autonomic neurons, control the release of different hormones that modulate insulin secretion. In pancreatic islets, the abundant presence of the granin protein VGF (nonacronymic; unrelated to VEGF) suggests that some of its proteolytically derived peptides could modulate hormone release. Thus, in the present study, we screened several VGF-derived peptides for their ability to induce insulin secretion, and we identified the VGF C-terminal peptide TLQP-62 as the most effective fragment. TLQP-62 induced a potent increase in basal insulin secretion as well as in glucose-stimulated insulin secretion in several insulinoma cell lines. We found that this peptide stimulated insulin release via increased intracellular calcium mobilization and fast expression of the insulin 1 gene. Moreover, the peripheral injection of TLQP-62 in mice improved glucose tolerance. Together, the present findings suggest that TLQP-62, acting as an endocrine, paracrine, or autocrine factor, can be considered a new, strong insulinotropic peptide that can be targeted for innovative antidiabetic drug discovery programs. © 2015 Society for Endocrinology.

  4. Unraveling the Roots of Selectivity of Peptide Affinity Reagents for Structurally Similar Ribosomal Inactivating Protein Derivatives

    Directory of Open Access Journals (Sweden)

    Deborah A. Sarkes

    2016-11-01

    Full Text Available Peptide capture agents have become increasingly useful tools for a variety of sensing applications due to their ease of discovery, stability, and robustness. Despite the ability to rapidly discover candidates through biopanning bacterial display libraries and easily mature them to Protein Catalyzed Capture (PCC agents with even higher affinity and selectivity, an ongoing challenge and critical selection criteria is that the peptide candidates and final reagent be selective enough to replace antibodies, the gold-standard across immunoassay platforms. Here, we have discovered peptide affinity reagents against abrax, a derivative of abrin with reduced toxicity. Using on-cell Fluorescence Activated Cell Sorting (FACS assays, we show that the peptides are highly selective for abrax over RiVax, a similar derivative of ricin originally designed as a vaccine, with significant structural homology to abrax. We rank the newly discovered peptides for strongest affinity and analyze three observed consensus sequences with varying affinity and specificity. The strongest (Tier 1 consensus was FWDTWF, which is highly aromatic and hydrophobic. To better understand the observed selectivity, we use the XPairIt peptide–protein docking protocol to analyze binding location predictions of the individual Tier 1 peptides and consensus on abrax and RiVax. The binding location profiles on the two proteins are quite distinct, which we determine is due to differences in pocket size, pocket environment (including hydrophobicity and electronegativity, and steric hindrance. This study provides a model system to show that peptide capture candidates can be quite selective for a structurally similar protein system, even without further maturation, and offers an in silico method of analysis for understanding binding and down-selecting candidates.

  5. Rho family proteins in cell adhesion and cell migration.

    Science.gov (United States)

    Evers, E E; Zondag, G C; Malliri, A; Price, L S; ten Klooster, J P; van der Kammen, R A; Collard, J G

    2000-06-01

    Cell migration and the regulation of cadherin-mediated homotypic cell-cell interactions are critical events during development, morphogenesis and wound healing. Aberrations in signalling pathways involved in the regulation of cell migration and cadherin-mediated cell-cell adhesion contribute to tumour invasion and metastasis. The rho family proteins, including cdc42, rac1 and rhoA, regulate signalling pathways that mediate the distinct actin cytoskeleton changes required for both cellular motility and cell-cell adhesion. Recent studies indicate that rac directly influences rho activity at the GTPase level and that the reciprocal balance between rac and rho activity can determine epithelial or mesenchymal cell morphology and migratory behaviour of epithelial (tumour) cells.

  6. Human DMBT1-Derived Cell-Penetrating Peptides for Intracellular siRNA Delivery

    Directory of Open Access Journals (Sweden)

    Martina Tuttolomondo

    2017-09-01

    Full Text Available Small interfering RNA (siRNA is a promising molecule for gene therapy, but its therapeutic administration remains problematic. Among the recently proposed vectors, cell-penetrating peptides show great promise in in vivo trials for siRNA delivery. Human protein DMBT1 (deleted in malignant brain tumor 1 is a pattern recognition molecule that interacts with polyanions and recognizes and aggregates bacteria. Taking advantage of these properties, we investigated whether specific synthetic DMBT1-derived peptides could be used to formulate nanoparticles for siRNA administration. Using an electrophoretic mobility shift assay and UV spectra, we identified two DMBT1 peptides that could encapsulate the siRNA with a self- and co-assembly mechanism. The complexes were stable for at least 2 hr in the presence of either fetal bovine serum (FBS or RNase A, with peptide-dependent time span protection. ζ-potential, circular dichroism, dynamic light scattering, and transmission electron microscopy revealed negatively charged nanoparticles with an average diameter of 10–800 nm, depending on the reaction conditions, and a spherical or rice-shaped morphology, depending on the peptide and β-helix conformation. We successfully transfected human MCF7 cells with fluorescein isothiocyanate (FITC-DMBT1-peptide-Cy3-siRNA complexes. Finally, DMBT1 peptides encapsulating an siRNA targeting a fluorescent reporter gene showed efficient gene silencing in MCF7-recombinant cells. These results lay the foundation for a new research line to exploit DMBT1-peptide nanocomplexes for therapeutic siRNA delivery.

  7. Ligand peptide-grafted PEGylated liposomes using HER2 targeted peptide-lipid derivatives for targeted delivery in breast cancer cells: The effect of serine-glycine repeated peptides as a spacer.

    Science.gov (United States)

    Suga, Tadaharu; Fuchigami, Yuki; Hagimori, Masayori; Kawakami, Shigeru

    2017-02-22

    Ligand peptide-grafted PEGylated liposomes have been widely studied for targeted drug delivery systems. Because ligand peptides are commonly grafted using PEG as a spacer on the surface of PEGylated liposomes, the interaction between ligand peptides and their corresponding receptors can be interrupted by steric hindrance of the PEG layer. Therefore, we aimed to develop ligand peptide-lipid derivatives to enhance the targeting efficiency of ligand peptide-grafted PEGylated liposomes, and designed a new ligand peptide-lipid derivatives having serine-glycine repeats (SG)n as a spacer based on the peptide length calculated by PyMol (v0.99). We selected KCCYSL (KCC) as the ligand peptide for binding to human epidermal growth factor receptor-2 (HER2). We synthesized new KCC-(SG)n-lipid derivatives (n=3, 5, 7) and evaluated their cellular association in breast cancer cells. KCC-(SG)n/PEGylated liposomes dramatically increased cellular association on HER2-positive breast cancer cells. The results suggest that KCC can be grafted on the surface of KCC-(SG)n/PEGylated liposomes prepared from KCC-(SG)n-lipid derivatives (n=3, 5, 7). In summary, we succeeded in developing KCC-(SG)n-lipid derivatives for the preparation of ligand peptide-grafted PEGylated liposomes.

  8. Spatially controlled cell adhesion on three-dimensional substrates.

    Science.gov (United States)

    Richter, Christine; Reinhardt, Martina; Giselbrecht, Stefan; Leisen, Daniel; Trouillet, Vanessa; Truckenmüller, Roman; Blau, Axel; Ziegler, Christiane; Welle, Alexander

    2010-10-01

    The microenvironment of cells in vivo is defined by spatiotemporal patterns of chemical and biophysical cues. Therefore, one important goal of tissue engineering is the generation of scaffolds with defined biofunctionalization in order to control processes like cell adhesion and differentiation. Mimicking extrinsic factors like integrin ligands presented by the extracellular matrix is one of the key elements to study cellular adhesion on biocompatible scaffolds. By using special thermoformable polymer films with anchored biomolecules micro structured scaffolds, e.g. curved and micro-patterned substrates, can be fabricated. Here, we present a novel strategy for the fabrication of micro-patterned scaffolds based on the "Substrate Modification and Replication by Thermoforming" (SMART) technology: The surface of a poly lactic acid membrane, having a low forming temperature of 60 degrees C and being initially very cell attractive, was coated with a photopatterned layer of poly(L-lysine) (PLL) and hyaluronic acid (VAHyal) to gain spatial control over cell adhesion. Subsequently, this modified polymer membrane was thermoformed to create an array of spherical microcavities with diameters of 300 microm for 3D cell culture. Human hepatoma cells (HepG2) and mouse fibroblasts (L929) were used to demonstrate guided cell adhesion. HepG2 cells adhered and aggregated exclusively within these cavities without attaching to the passivated surfaces between the cavities. Also L929 cells adhering very strongly on the pristine substrate polymer were effectively patterned by the cell repellent properties of the hyaluronic acid based hydrogel. This is the first time cell adhesion was controlled by patterned functionalization of a polymeric substrate with UV curable PLL-VAHyal in thermoformed 3D microstructures.

  9. Analysis of Dengue Virus Enhancing Epitopes Using Peptide Antigens Derived from the Envelope Glycoprotein Gene Sequence

    Science.gov (United States)

    1990-11-27

    WE. 1990. Development of dengue and Japanese encephalitis Vaccines . J Infect Dis 162:577-83. 2. Brandt WE, McCown JM, Gentry MK, and Russell PK. i982...7. 19. Roehrig JT, Johnson AJ, Hunt AR, Bolin RA, •d Chu MC. 1990. Antibodies to dengue 2 Jamaica E-glycopr tein synthetic peptides identify antigenic...AD________ AD-A230 976 ARMY PROJECT NO: 89PP9961 TITLE: ANALYSIS OF DENGUE VIRUS ENHANCING EPITOPES USING PEPTIDE ANTIGENS DERIVED FROM THE ENVELOPE

  10. The expanding roles of the ghrelin-gene derived peptide obestatin in health and disease.

    Science.gov (United States)

    Seim, Inge; Walpole, Carina; Amorim, Laura; Josh, Peter; Herington, Adrian; Chopin, Lisa

    2011-06-20

    Obestatin is a 23 amino acid, ghrelin gene-derived peptide hormone produced in the stomach and a range of other tissues throughout the body. While it was initially reported that obestatin opposed the actions of ghrelin with regards to appetite and food intake, it is now clear that obestatin is not an endogenous ghrelin antagonist, but it is a multi-functional peptide hormone in its own right. In this review we will discuss the controversies associated with the discovery of obestatin and explore emerging central and peripheral roles of obestatin, which includes adipogenesis, pancreatic homeostasis and cancer.

  11. Hydrogen peroxide regulates cell adhesion through the redox sensor RPSA.

    Science.gov (United States)

    Vilas-Boas, Filipe; Bagulho, Ana; Tenente, Rita; Teixeira, Vitor H; Martins, Gabriel; da Costa, Gonçalo; Jerónimo, Ana; Cordeiro, Carlos; Machuqueiro, Miguel; Real, Carla

    2016-01-01

    To become metastatic, a tumor cell must acquire new adhesion properties that allow migration into the surrounding connective tissue, transmigration across endothelial cells to reach the blood stream and, at the site of metastasis, adhesion to endothelial cells and transmigration to colonize a new tissue. Hydrogen peroxide (H2O2) is a redox signaling molecule produced in tumor cell microenvironment with high relevance for tumor development. However, the molecular mechanisms regulated by H2O2 in tumor cells are still poorly known. The identification of H2O2-target proteins in tumor cells and the understanding of their role in tumor cell adhesion are essential for the development of novel redox-based therapies for cancer. In this paper, we identified Ribosomal Protein SA (RPSA) as a target of H2O2 and showed that RPSA in the oxidized state accumulates in clusters that contain specific adhesion molecules. Furthermore, we showed that RPSA oxidation improves cell adhesion efficiency to laminin in vitro and promotes cell extravasation in vivo. Our results unravel a new mechanism for H2O2-dependent modulation of cell adhesion properties and identify RPSA as the H2O2 sensor in this process. This work indicates that high levels of RPSA expression might confer a selective advantage to tumor cells in an oxidative environment.

  12. A Review of Potential Marine-derived Hypotensive and Anti-obesity Peptides.

    Science.gov (United States)

    Manikkam, V; Vasiljevic, T; Donkor, O N; Mathai, M L

    2016-01-01

    Bioactive peptides are food derived components, usually consisting of 3-20 amino acids, which are inactive when incorporated within their parent protein. Once liberated by enzymatic or chemical hydrolysis, during food processing and gastrointestinal transit, they can potentially provide an array of health benefits to the human body. Owing to an unprecedented increase in the worldwide incidence of obesity and hypertension, medical researchers are focusing on the hypotensive and anti-obesity properties of nutritionally derived bioactive peptides. The role of the renin-angiotensin system has long been established in the aetiology of metabolic diseases and hypertension. Targeting the renin-angiotensin system by inhibiting the activity of angiotensin-converting enzyme (ACE) and preventing the formation of angiotensin II can be a potential therapeutic approach to the treatment of hypertension and obesity. Fish-derived proteins and peptides can potentially be excellent sources of bioactive components, mainly as a source of ACE inhibitors. However, increased use of marine sources, poses an unsustainable burden on particular fish stocks, so, the underutilized fish species and by-products can be exploited for this purpose. This paper provides an overview of the techniques involved in the production, isolation, purification, and characterization of bioactive peptides from marine sources, as well as the evaluation of the ACE inhibitory (ACE-I) activity and bioavailability.

  13. BCR-ABL DERIVED PEPTIDE VACCINES FOR CHRONIC MYELOID LEUKAEMIA

    Directory of Open Access Journals (Sweden)

    M. Bocchia

    2012-01-01

    Full Text Available Chronic Myeloid Leukemia (CML is a myeloproliferative pluripotent stem cell disorder characterized by the presence of a cytogenetic hallmark, the Philadelphia (Ph chromosome, and accounts for 15% of adult leukemias. The disease progresses from a chronic phase through an accelerated phase to a blast phase and its natural course accounts for a median 4 years survival1. The Ph chromosome is derived by a reciprocal translocation termed t(9;22 in which the c-abl oncogene has moved from chromosome 9 into the breakpoint cluster region (bcr, within the bcr gene on chromosome 22, resulting in a chimeric bcr-abl fusion gene that encodes a 210 KD protein (p210 with constitutive tyrosine kinase activity. Two major alternative chimeric p210 can result from this fusion gene: p210-b2a2 where the junction occurs between bcr exon 2 (b2 and abl exon 2 (a2 and p210-b3a2 where the the junction occurs between bcr exon 3 (b3 and abl exon 2 (a2. About 40% of CML patients harbor the p210-b2a2 and about 60% of them show the p210-b3a2.

  14. Antibody-independent identification of bovine milk-derived peptides in breast-milk.

    Science.gov (United States)

    Picariello, Gianluca; Addeo, Francesco; Ferranti, Pasquale; Nocerino, Rita; Paparo, Lorella; Passariello, Annalisa; Dallas, David C; Robinson, Randall C; Barile, Daniela; Canani, Roberto Berni

    2016-08-10

    Exclusively breast-fed infants can exhibit clear signs of IgE or non IgE-mediated cow's milk allergy. However, the definite characterization of dietary cow's milk proteins (CMP) that survive the maternal digestive tract to be absorbed into the bloodstream and secreted into breast milk remains missing. Herein, we aimed at assessing possible CMP-derived peptides in breast milk. Using high performance liquid chromatography (HPLC)-high resolution mass spectrometry (MS), we compared the peptide fraction of breast milk from 12 donors, among which 6 drank a cup of milk daily and 6 were on a strict dairy-free diet. We identified two bovine β-lactoglobulin (β-Lg, 2 out 6 samples) and one αs1-casein (1 out 6 samples) fragments in breast milk from mothers receiving a cup of bovine milk daily. These CMP-derived fragments, namely β-Lg (f42-54), (f42-57) and αs1-casein (f180-197), were absent in milk from mothers on dairy-free diet. In contrast, neither intact nor hydrolyzed β-Lg was detected by western blot and competitive ELISA in any breast milk sample. Eight additional bovine milk-derived peptides identified by software-assisted MS were most likely false positive. The results of this study demonstrate that CMP-derived peptides rather than intact CMP may sensitize or elicit allergic responses in the neonate through mother's milk. Immunologically active peptides from the maternal diet could be involved in priming the newborn's immune system, driving a tolerogenic response.

  15. Processing of pro-opiomelanocortin-derived amidated joining peptide and glycine-extended precursor in monkey pituitary

    DEFF Research Database (Denmark)

    Fenger, M

    1991-01-01

    The molecular forms of proopiomelanocortin (POMC) derived amidated and C-terminal glycine-extended joining peptide from monkey (Macaca mulatta) pituitary were determined. The predominant forms of joining peptide found were the low molecular peptides POMC(76-105) and POMC(76-106), respectively....... Significant amounts of N-terminally truncated POMC(78-105) and POMC(78-106) were also detected in the posterior-intermediate lobe. No N-terminal extended forms were detected. The relative amount of amidated joining peptide to total joining peptide was 6-35%. It is concluded that not only is the primary...

  16. Ion implantation induced nanotopography on titanium and bone cell adhesion

    Energy Technology Data Exchange (ETDEWEB)

    Braceras, Iñigo, E-mail: inigo.braceras@tecnalia.com [Tecnalia, Mikeletegi Pasealekua 2, 20009 Donostia-San Sebastian (Spain); CIBER de Bioingeniería, Biomateriales y Nanomedicina (Ciber-BBN) (Spain); Vera, Carolina; Ayerdi-Izquierdo, Ana [Tecnalia, Mikeletegi Pasealekua 2, 20009 Donostia-San Sebastian (Spain); CIBER de Bioingeniería, Biomateriales y Nanomedicina (Ciber-BBN) (Spain); Muñoz, Roberto [Tecnalia, Mikeletegi Pasealekua 2, 20009 Donostia-San Sebastian (Spain); Lorenzo, Jaione; Alvarez, Noelia [Tecnalia, Mikeletegi Pasealekua 2, 20009 Donostia-San Sebastian (Spain); CIBER de Bioingeniería, Biomateriales y Nanomedicina (Ciber-BBN) (Spain); Maeztu, Miguel Ángel de [Private Practice, P° San Francisco, 43 A-1°, 20400 Tolosa (Spain)

    2014-08-15

    Graphical abstract: Titanium surfaces modified by inert ion implantation affect cell adhesion through modification of the nanotopography in the same dimensional range of that of human bone inorganic phases. - Highlights: • Inert ion implantation on Ti modifies surface nanotopography and bone cell adhesion. • Ion implantation can produce nanostructured surfaces on titanium in the very same range as of those of the mineral phase of the human bone. • Appropriate tool for studying the relevance of nanostructured surfaces on bone mineralization and implant osseointegration. • Ion implantation induced nanotopography have a statistically significant influence on bone cell adhesion. - Abstract: Permanent endo-osseous implants require a fast, reliable and consistent osseointegration, i.e. intimate bonding between bone and implant, so biomechanical loads can be safely transferred. Among the parameters that affect this process, it is widely admitted that implant surface topography, surface energy and composition play an important role. Most surface treatments to improve osseointegration focus on micro-scale features, as few can effectively control the effects of the treatment at nanoscale. On the other hand, ion implantation allows controlling such nanofeatures. This study has investigated the nanotopography of titanium, as induced by different ion implantation surface treatments, its similarity with human bone tissue structure and its effect on human bone cell adhesion, as a first step in the process of osseointegration. The effect of ion implantation treatment parameters such as energy (40–80 keV), fluence (1–2 e17 ion/cm{sup 2}) and ion species (Kr, Ar, Ne and Xe) on the nanotopography of medical grade titanium has been measured and assessed by AFM and contact angle. Then, in vitro tests have been performed to assess the effect of these nanotopographies on osteoblast adhesion. The results have shown that the nanostructure of bone and the studied ion implanted

  17. Alpha-amidated peptides derived from pro-opiomelanocortin in normal human pituitary

    DEFF Research Database (Denmark)

    Fenger, M; Johnsen, A H

    1988-01-01

    Normal human pituitaries were extracted in boiling water and acetic acid, and the alpha-amidated peptide products of pro-opiomelanocortin (POMC), alpha-melanocyte-stimulating hormone (alpha MSH), gamma-melanocyte-stimulating hormone (gamma 1MSH), and amidated hinge peptide (HP-N), as well...... as their glycine-extended precursors, were characterized by sequence-specific radioimmunoassays, gel-chromatography, h.p.l.c. and amino acid sequencing. alpha MSH and gamma 1MSH constituted 0.27-1.32% and 0.10-5.10%, respectively, of the POMC-derived products [calculated as the sum of adrenocorticotropic hormone...... (ACTH)-(1-39), ACTH-(1-14) and alpha MSH immunoreactivity]. alpha MSH and ACTH-(1-14) were only present in non- or mono-acetylated forms. Only large forms of gamma 1MSH and gamma 2MSH were present in partly glycosylated states. The hinge peptides were amidated to an extent two to three orders...

  18. A biomimetic collagen derived peptide exhibits anti-angiogenic activity in triple negative breast cancer.

    Directory of Open Access Journals (Sweden)

    Elena V Rosca

    Full Text Available We investigated the application of a mimetic 20 amino acid peptide derived from type IV collagen for treatment of breast cancer. We showed that the peptide induced a decrease of proliferation, adhesion, and migration of endothelial and tumor cells in vitro. We also observed an inhibition of triple negative MDA-MB-231 xenograft growth by 75% relative to control when administered intraperitoneally for 27 days at 10 mg/kg. We monitored in vivo the changes in vascular properties throughout the treatment using MRI and found that the vascular volume and permeability surface area product decreased significantly. The treatment also resulted in an increase of caspase-3 activity and in a reduction of microvascular density. The multiple mode of action of this peptide, i.e., anti-angiogenic, and anti-tumorigenic, makes it a viable candidate as a therapeutic agent as a monotherapy or in combination with other compounds.

  19. Drying Technology of Angiotensin Converting Enzyme Inhibitory Peptide Derived from Bovine Casein

    Institute of Scientific and Technical Information of China (English)

    JIANG Zhanmei; Hue Guicheng; TIAN Be

    2009-01-01

    Drying technology of angiotensin converting enzyme (ACE) inhibitory peptides derived from bovine casein was investigated. No significance was observed on ACE inhibitory activity of products prepared by spay drying and freeze drying (P>0.05). Spay drying was the best drying process for practical industry production. The inlet temperature ranged from 140℃ to 160℃ and the exit temperature ranged from 70℃ to 90℃ during the spay drying process. Under the optimal eonditious, scale-up of angiotensin converted enzyme inhibitory peptide from 1 L to 10 L and the experiment was successively conducted. Peptide yield was 29% and half inhibitory concentration(IC50) was 0.53g·L-1.

  20. A chirality change in XPC- and Sfi1-derived peptides affects their affinity for centrin.

    Science.gov (United States)

    Grecu, Dora; Irudayaraj, Victor Paul Raj; Martinez-Sanz, Juan; Mallet, Jean-Maurice; Assairi, Liliane

    2016-04-01

    The Ca(2+)-binding protein centrin binds to a hydrophobic motif (W(1)xxL(4)xxxL(8)) included in the sequence of several cellular targets: XPC (xeroderma pigmentosum group C protein), Sfi1 (suppressor of fermentation-induced loss of stress resistance protein1), and Sac3 [the central component of the transcription and mRNA export (TREX-2) complex]. However, centrin binding occurs in a reversed orientation (L(8)xxxL(4)xxW(1)) for Sfi1 and Sac3 compared with XPC. Because D-peptides have been investigated for future therapeutic use, we analyzed their centrin-binding properties. Their affinity for centrin was measured using isothermal titration calorimetry. The chirality change in the target-derived peptides affected their ability to bind centrin in a specific manner depending on the sequence orientation of the centrin-binding motif. In contrast to L-XPC-P10, D-XPC-P10 bound C-HsCen1 in a Ca(2+)-dependent manner and to a lesser extent. D-XPC-P10 exhibited a reduced affinity for C-HsCen1 (Ka=0.064 × 10(6) M(-1)) by a factor of 2000 compared with L-XPC-P10 (Ka=132 × 10(6) M(-1)). D-peptides have a lower affinity than L-peptides for centrin, and the strength of this affinity depends on the sequence orientation of the target-derived peptides. The residual affinity observed for D-XPC suggests that the use of d-peptides represents a promising strategy for inhibiting centrin binding to its targets.

  1. Peptides derived from HIV-1, HIV-2, Ebola virus, SARS coronavirus and coronavirus 229E exhibit high affinity binding to the formyl peptide receptor

    Science.gov (United States)

    Mills, John S.

    2007-01-01

    Peptides derived from the membrane proximal region of fusion proteins of human immunodeficiency viruses 1 and 2, Coronavirus 229 E, severe acute respiratory syndrome coronavirus and Ebola virus were all potent antagonists of the formyl peptide receptor expressed in Chinese hamster ovary cells. Binding of viral peptides was affected by the naturally occurring polymorphisms at residues 190 and 192, which are located at second extracellular loop-transmembrane helix 5 interface. Substitution of R190 with W190 enhanced the affinity for a severe acute respiratory syndrome coronavirus peptide 6 fold but reduced the affinity for N-formyl-Nle–Leu-Phe by 2.5 fold. A 12 mer peptide derived from coronavirus 229E (ETYIKPWWVWL) was the most potent antagonist of the formyl peptide receptor W190 with a Ki of 230 nM. Fluorescently labeled ETYIKPWWVWL was effectively internalized by all three variants with EC50 of ~25 nM. An HKU-1 coronavirus peptide, MYVKWPWYVWL, was a potent antagonist but N-formyl-MYVKWPWYVWL was a potent agonist. ETYIKPWWVWL did not stimulate GTPγS binding but inhibited the stimulation by formyl-NleLeuPhe. It also blocked β arrestin translocation and receptor downregulation induced by formyl-Nle–Leu–Phe. This indicates that formyl peptide receptor may be important in viral infections and that variations in its sequence among individuals may affect their likelihood of viral and bacterial infections. PMID:16842982

  2. Cementomimetics-constructing a cementum-like biomineralized microlayer via amelogenin-derived peptides.

    Science.gov (United States)

    Gungormus, Mustafa; Oren, Ersin E; Horst, Jeremy A; Fong, Hanson; Hnilova, Marketa; Somerman, Martha J; Snead, Malcolm L; Samudrala, Ram; Tamerler, Candan; Sarikaya, Mehmet

    2012-06-01

    Cementum is the outer-, mineralized-tissue covering the tooth root and an essential part of the system of periodontal tissue that anchors the tooth to the bone. Periodontal disease results from the destructive behavior of the host elicited by an infectious biofilm adhering to the tooth root and left untreated, may lead to tooth loss. We describe a novel protocol for identifying peptide sequences from native proteins with the potential to repair damaged dental tissues by controlling hydroxyapatite biomineralization. Using amelogenin as a case study and a bioinformatics scoring matrix, we identified regions within amelogenin that are shared with a set of hydroxyapatite-binding peptides (HABPs) previously selected by phage display. One 22-amino acid long peptide regions referred to as amelogenin-derived peptide 5 (ADP5) was shown to facilitate cell-free formation of a cementum-like hydroxyapatite mineral layer on demineralized human root dentin that, in turn, supported attachment of periodontal ligament cells in vitro. Our findings have several implications in peptide-assisted mineral formation that mimic biomineralization. By further elaborating the mechanism for protein control over the biomineral formed, we afford new insights into the evolution of protein-mineral interactions. By exploiting small peptide domains of native proteins, our understanding of structure-function relationships of biomineralizing proteins can be extended and these peptides can be utilized to engineer mineral formation. Finally, the cementomimetic layer formed by ADP5 has the potential clinical application to repair diseased root surfaces so as to promote the regeneration of periodontal tissues and thereby reduce the morbidity associated with tooth loss.

  3. Angiotensin I Converting Enzyme Inhibitory Peptides Derived from Phycobiliproteins of Dulse Palmaria palmata.

    Science.gov (United States)

    Furuta, Tomoe; Miyabe, Yoshikatsu; Yasui, Hajime; Kinoshita, Yasunori; Kishimura, Hideki

    2016-02-04

    We examined the inhibitory activity of angiotensin I converting enzyme (ACE) in protein hydrolysates from dulse, Palmaria palmata. The proteins extracted from dulse were mainly composed of phycoerythrin (PE) followed by phycocyanin (PC) and allophycocyanin (APC). The dulse proteins showed slight ACE inhibitory activity, whereas the inhibitory activity was extremely enhanced by thermolysin hydrolysis. The ACE inhibitory activity of hydrolysates was hardly affected by additional pepsin, trypsin and chymotrypsin treatments. Nine ACE inhibitory peptides (YRD, AGGEY, VYRT, VDHY, IKGHY, LKNPG, LDY, LRY, FEQDWAS) were isolated from the hydrolysates by reversed-phase high-performance liquid chromatography (HPLC), and it was demonstrated that the synthetic peptide LRY (IC50: 0.044 μmol) has remarkably high ACE inhibitory activity. Then, we investigated the structural properties of dulse phycobiliproteins to discuss the origin of dulse ACE inhibitory peptides. Each dulse phycobiliprotein possesses α-subunit (Mw: 17,477-17,638) and β-subunit (Mw: 17,455-18,407). The sequences of YRD, AGGEY, VYRT, VDHY, LKNPG and LDY were detected in the primary structure of PE α-subunit, and the LDY also exists in the APC α- and β-subunits. In addition, the LRY sequence was found in the β-subunits of PE, PC and APC. From these results, it was suggested that the dulse ACE inhibitory peptides were derived from phycobiliproteins, especially PE. To make sure the deduction, we carried out additional experiment by using recombinant PE. We expressed the recombinant α- and β-subunits of PE (rPEα and rPEβ, respectively), and then prepared their peptides by thermolysin hydrolysis. As a result, these peptides showed high ACE inhibitory activities (rPEα: 94.4%; rPEβ: 87.0%). Therefore, we concluded that the original proteins of dulse ACE inhibitory peptides were phycobiliproteins.

  4. Angiotensin I Converting Enzyme Inhibitory Peptides Derived from Phycobiliproteins of Dulse Palmaria palmata

    Directory of Open Access Journals (Sweden)

    Tomoe Furuta

    2016-02-01

    Full Text Available We examined the inhibitory activity of angiotensin I converting enzyme (ACE in protein hydrolysates from dulse, Palmaria palmata. The proteins extracted from dulse were mainly composed of phycoerythrin (PE followed by phycocyanin (PC and allophycocyanin (APC. The dulse proteins showed slight ACE inhibitory activity, whereas the inhibitory activity was extremely enhanced by thermolysin hydrolysis. The ACE inhibitory activity of hydrolysates was hardly affected by additional pepsin, trypsin and chymotrypsin treatments. Nine ACE inhibitory peptides (YRD, AGGEY, VYRT, VDHY, IKGHY, LKNPG, LDY, LRY, FEQDWAS were isolated from the hydrolysates by reversed-phase high-performance liquid chromatography (HPLC, and it was demonstrated that the synthetic peptide LRY (IC50: 0.044 μmol has remarkably high ACE inhibitory activity. Then, we investigated the structural properties of dulse phycobiliproteins to discuss the origin of dulse ACE inhibitory peptides. Each dulse phycobiliprotein possesses α-subunit (Mw: 17,477–17,638 and β-subunit (Mw: 17,455–18,407. The sequences of YRD, AGGEY, VYRT, VDHY, LKNPG and LDY were detected in the primary structure of PE α-subunit, and the LDY also exists in the APC α- and β-subunits. In addition, the LRY sequence was found in the β-subunits of PE, PC and APC. From these results, it was suggested that the dulse ACE inhibitory peptides were derived from phycobiliproteins, especially PE. To make sure the deduction, we carried out additional experiment by using recombinant PE. We expressed the recombinant α- and β-subunits of PE (rPEα and rPEβ, respectively, and then prepared their peptides by thermolysin hydrolysis. As a result, these peptides showed high ACE inhibitory activities (rPEα: 94.4%; rPEβ: 87.0%. Therefore, we concluded that the original proteins of dulse ACE inhibitory peptides were phycobiliproteins.

  5. Anticancer activity of a synthetic peptide derived from harmoniasin, an antibacterial peptide from the ladybug Harmonia axyridis.

    Science.gov (United States)

    Kim, In-Woo; Lee, Joon Ha; Kwon, Young-Nam; Yun, Eun-Young; Nam, Sung-Hee; Ahn, Mi-Young; Kang, Dong-Chul; Hwang, Jae Sam

    2013-08-01

    Harmoniasin is a defensin-like antimicrobial peptide identified from the ladybug Harmonia axyridis. Among the synthetic homodimer peptide analogues derived from harmoniasin, HaA4 has been found to have antibacterial activity without hemolytic activity. In this study, we investigated whether HaA4 has anticancer activity against human leukemia cell lines such as U937 and Jurkat cells. HaA4 manifested cytotoxicity and decreased the cell viability of U937 and Jurkat cells in MTS assay and LDH release assay. We found that HaA4 induced apoptotic and necrotic cell death of the leukemia cells using flow cytometric analysis, acridine orange/ethidium bromide staining and nucleosomal fragmentation of genomic DNA. Activation of caspase-7 and -9 and fragmentation of poly (ADP-ribose) polymerase was detected in the HaA4-treated leukemia cells, suggesting induction of a caspase-dependent apoptosis pathway by HaA4. Caspase-dependent apoptosis was further confirmed by reversal of the HaA4-induced viability reduction by treatment of Z-VAD-FMK, a pan-caspase inhibitor. In conclusion, HaA4 caused necrosis and caspase-dependent apoptosis in both U937 and Jurkat leukemia cells, which suggests potential utility of HaA4 as a cancer therapeutic agent.

  6. Alpha-amidated peptides derived from pro-opiomelanocortin in human pituitary tumours

    DEFF Research Database (Denmark)

    Fenger, M; Johnsen, A H

    1988-01-01

    (HPLC) and sequence analysis. In the tumours from patients with Cushing's disease the mean concentrations of amidated peptides relative to the total amount of POMC were as follows: alpha-MSH, 1.7%; amidated gamma-MSH (gamma 1-MSH), 8.5% and the peptide linking gamma-MSH and ACTH in the precursor (hinge......Human pituitary tumours, obtained at surgery for Cushing's disease and Nelson's syndrome, were extracted and the content and molecular forms of pro-opiomelanocortin (POMC)-derived peptides determined by radioimmunoassay, gel chromatography, reversed-phase high-performance liquid chromatography...... peptide or joining peptide) in its amidated form (HP-N), 17.1%. The same relative concentrations in the tumours from patients with Nelson's syndrome were 8.5% (alpha-MSH), 7.5% (gamma 1-MSH) and 12.2% (HP-N). More than 95% of the ACTH(1-39) immunoreactivity eluted as synthetic ACTH(1-39) by gel...

  7. Thiol-disulfide exchange in peptides derived from human growth hormone.

    Science.gov (United States)

    Chandrasekhar, Saradha; Epling, Daniel E; Sophocleous, Andreas M; Topp, Elizabeth M

    2014-04-01

    Disulfide bonds stabilize proteins by cross-linking distant regions into a compact three-dimensional structure. They can also participate in hydrolytic and oxidative pathways to form nonnative disulfide bonds and other reactive species. Such covalent modifications can contribute to protein aggregation. Here, we present experimental data for the mechanism of thiol-disulfide exchange in tryptic peptides derived from human growth hormone in aqueous solution. Reaction kinetics was monitored to investigate the effect of pH (6.0-10.0), temperature (4-50°C), oxidation suppressants [ethylenediaminetetraacetic acid (EDTA) and N2 sparging], and peptide secondary structure (amide cyclized vs. open form). The concentrations of free thiol containing peptides, scrambled disulfides, and native disulfide-linked peptides generated via thiol-disulfide exchange and oxidation reactions were determined using reverse-phase HPLC and liquid chromatography-mass spectrometry. Concentration versus time data were fitted to a mathematical model using nonlinear least squares regression analysis. At all pH values, the model was able to fit the data with R(2) ≥ 0.95. Excluding oxidation suppressants (EDTA and N2 sparging) resulted in an increase in the formation of scrambled disulfides via oxidative pathways but did not influence the intrinsic rate of thiol-disulfide exchange. In addition, peptide secondary structure was found to influence the rate of thiol-disulfide exchange.

  8. Inhibitory activity of the peptides derived from buffalo prolactin on angiogenesis

    Indian Academy of Sciences (India)

    Jaeok Lee; Syamantak Majumder; Suvro Chatterjee; Kambadur Muralidhar

    2011-06-01

    The peptide fragments obtained by cathepsin digestion of purified buffalo prolactin (buPRL) monomer have been characterized using SDS-PAGE and FPLC with regard to size and pI. Their antiangiogenic activity was tested in chick embryo chorioallantoic membrane (CAM) assay and the human endothelial cells wound healing assay. Antiangiogenic activity was observed in cathepsin-cleaved fragments from buPRL. Further, a peptide sequence 45A-46Q-47G-48K-49G-50F-51I-52T-53M-54A-55L-56N-57S-58C, which matched with human somatostatin (hSST), a known antiangiogenic factor, was located in the second loop between the first and second α-helices in the threedimensional structure of buPRL, obtained by homology modelling. The synthetic peptide matching with SST sequence was found to exhibit antiangiogenic activity in both in vitro and ex vivo assays. It was also observed that all the peptides related to buPRL could antagonize the vascular endothelial growth factor (VEGF) and bradykinin (BK)-dependent production of endothelial nitric oxide (NO), which is a pre-requisite for endothelial tube formation. It is concluded therefore that an internal sequence in buPRL and peptide fragments derived from cathepsin-digested buPRL exhibit antiangiogenic activities.

  9. Conformational analysis of Infectious bursal disease virus (IBDV derived cell penetrating peptide (CPP analogs

    Directory of Open Access Journals (Sweden)

    Vinay G. Joshi

    2013-12-01

    Full Text Available Aim: This study was designed to develop peptide analogs of Infectious Bursal Disease (IBD virus VP5 protein segment having cell penetrating ability to improve their interaction with cargo molecule (Nucleic acid without affecting the backbone conformation. Materials and Methods: IBDV VP5 protein segment designated as RATH peptide were synthesized using solid phase peptide synthesis and their solution conformation was elucidated using CD spectroscopy in polar (water and apolar (TFE solvents. Cell penetrating ability of RATH-CONH2 was observed using FITC labeled peptide internalization in to HeLa cells under fluorescent microscopy. The efficacy of RATH analog interactions with nucleic acids was evaluated using FITC labeled oligonucleotides by fluorescence spectroscopy and plasmid constructs in gel retardation assay. Results: CD spectra of RATH analogs in water and apolar trifluroethanol (TFE helped to compare their secondary structures which were almost similar with dominant beta conformations suggesting successful induction of positive charge in the analogs without affecting back bone conformation of CPP designed. Cell penetrating ability of RATH CONH2 in HeLa cell was more than 90%. The fluorescence spectroscopy and plasmid constructs in gel retardation assay demonstrated successful interaction of amide analogs with nucleic acid. Conclusion: Intentional changes made in IBDV derived peptide RATH COOH to RATH CONH2 did not showed major changes in backbone conformation and such modifications may help to improve the cationic charge in most CPPs to interact with nucleic acid. [Vet World 2013; 6(6.000: 307-312

  10. HOMOLOGY MODELING AND MOLECULAR DYNAMICS STUDIES OF EC1 DOMAIN OF VE-CADHERIN TO ELUCIDATE DOCKING INTERACTION WITH CADHERIN-DERIVED PEPTIDE

    Directory of Open Access Journals (Sweden)

    Vivitri Dewi Prasasty

    2014-01-01

    Full Text Available VE-cadherin is a protein in the cadherin family that is found at the adherens junctions of the microvessel endothelial cells of the Blood-Brain Barrier (BBB. It is recognized as the homotypic cell adhesion molecules and there is limited structural information on how VE-cadherins mediate cell-cell adhesion. It has been shown that the EC1 domain of cadherins is important for the homophilic interactions for cell-cell adhesion. Therefore, the aims of this study are to model the structure of the EC1 domain of VE-cadherin, study its molecular dynamics properties and evaluate its interactions with cadherin peptides. In this study, the sequence alignment between EC1 domain of VE-cadherin and the template protein were conducted by CLUSTALW2 platform. The SWISS-MODEL platform performed the homology modeling of the EC1 domain of VE-cadherin structure. Structural refinement was done by using KOBAMIN. Some validation analysis platforms also were conducted included PROCHECK, VERIFY3D, ERRAT and MOLPROBITY to check the allowed residues region in Ramachandran Plot (RP and the quality of the structure. The most favored region was found 95.5% in RP value and overall model structure quality is 71.34%. Molecular Dynamics (MD was run under CABS-FLEX to determine the flexibility of the residue index. The RMSD value of MD is 1.5Å per residue index. Eventually, molecular docking by AUTODOCK VINA was conducted to investigate protein-ligand interaction. From docking, it is found that the affinity energy is -4.8 kcal/mol which has the most favorable binding of EC1 domain with the peptide.

  11. Anti-HIV-1 activity of a new scorpion venom peptide derivative Kn2-7.

    Directory of Open Access Journals (Sweden)

    Yaoqing Chen

    Full Text Available For over 30 years, HIV/AIDS has wreaked havoc in the world. In the absence of an effective vaccine for HIV, development of new anti-HIV agents is urgently needed. We previously identified the antiviral activities of the scorpion-venom-peptide-derived mucroporin-M1 for three RNA viruses (measles viruses, SARS-CoV, and H5N1. In this investigation, a panel of scorpion venom peptides and their derivatives were designed and chosen for assessment of their anti-HIV activities. A new scorpion venom peptide derivative Kn2-7 was identified as the most potent anti-HIV-1 peptide by screening assays with an EC(50 value of 2.76 µg/ml (1.65 µM and showed low cytotoxicity to host cells with a selective index (SI of 13.93. Kn2-7 could inhibit all members of a standard reference panel of HIV-1 subtype B pseudotyped virus (PV with CCR5-tropic and CXCR4-tropic NL4-3 PV strain. Furthermore, it also inhibited a CXCR4-tropic replication-competent strain of HIV-1 subtype B virus. Binding assay of Kn2-7 to HIV-1 PV by Octet Red system suggested the anti-HIV-1 activity was correlated with a direct interaction between Kn2-7 and HIV-1 envelope. These results demonstrated that peptide Kn2-7 could inhibit HIV-1 by direct interaction with viral particle and may become a promising candidate compound for further development of microbicide against HIV-1.

  12. PURIFICATION OF ANGIOTENSIN CONVERTING ENZYME INHIBITORY PEPTIDE DERIVED FROM KACANG GOAT MEAT PROTEIN HYDROLYSATE

    Directory of Open Access Journals (Sweden)

    J. Jamhari

    2014-10-01

    Full Text Available The objective of this study was to identify the Angiotensin Converting Enzyme (ACE inhibitorypeptide derived from Kacang goat meat protein hydrolysate. Kacang goat meat loin section washydrolyzed with pepsin, trypsin and chymotrypsin. Protein hydrolysate of Kacang goat meat was thentested the protein concentration and ACE inhibitory activity. ACE inhibitory peptide of the proteinhydrolysate was purified through several steps of purification by column SEP-PAK Plus C18 Cartridgeand RP-HPLC using a Cosmosil column 5PE-SM, 4.6 x 250 mm. The sequence of amino acid of ACEinhibitory peptide was identified by amino acid sequencer. The results showed that amino acidssequence of ACE inhibitory peptide derived from protein hydrolysate of Kacang goat meat was leu-thrglu-ala-pro-leu-asn-pro-lys-ala-arg- asn-glu-lys. It had a molecular weight (MW of 1581 and occurredat the position of 20th to 33rd residues of b-actin of goat meat protein (Capra hircus. The ACE inhibitoryactivity (IC50 of the peptide was 190 mg/mL or 120 mM.

  13. Anti-Hemagglutinin Antibody Derived Lead Peptides for Inhibitors of Influenza Virus Binding.

    Directory of Open Access Journals (Sweden)

    Henry Memczak

    Full Text Available Antibodies against spike proteins of influenza are used as a tool for characterization of viruses and therapeutic approaches. However, development, production and quality control of antibodies is expensive and time consuming. To circumvent these difficulties, three peptides were derived from complementarity determining regions of an antibody heavy chain against influenza A spike glycoprotein. Their binding properties were studied experimentally, and by molecular dynamics simulations. Two peptide candidates showed binding to influenza A/Aichi/2/68 H3N2. One of them, termed PeB, with the highest affinity prevented binding to and infection of target cells in the micromolar region without any cytotoxic effect. PeB matches best the conserved receptor binding site of hemagglutinin. PeB bound also to other medical relevant influenza strains, such as human-pathogenic A/California/7/2009 H1N1, and avian-pathogenic A/Mute Swan/Rostock/R901/2006 H7N1. Strategies to improve the affinity and to adapt specificity are discussed and exemplified by a double amino acid substituted peptide, obtained by substitutional analysis. The peptides and their derivatives are of great potential for drug development as well as biosensing.

  14. Inhibition of the wine spoilage yeast Dekkera bruxellensis by bovine lactoferrin-derived peptides.

    Science.gov (United States)

    Enrique, María; Marcos, Jose F; Yuste, María; Martínez, Mireia; Vallés, Salvador; Manzanares, Paloma

    2008-10-31

    The antimicrobial action of lactoferrin (LF)-derived peptides against Dekkera bruxellensis strains isolated from spoiled wines has been examined. The study included a fifteen-residue peptide (LfcinB(17-31)) derived from bovine lactoferricin B and a bovine LF pepsin hydrolysate (LFH). In vitro assays showed the inhibitory properties of LfcinB(17-31) on D. bruxellensis growth with IC(50) and MIC values in the micromolar range. Strains tested showed different sensitivity to the peptide. LfcinB(17-31) showed fungicidal properties towards all strains tested in laboratory growth medium. However, the extent of fungicidal activity was strain-dependent in must and wine, confirming the different antimicrobial action of peptides depending on both the food matrix and the target micro-organism. The binding of LfcinB(17-31) to D. bruxellensis cells was visualized by fluorescence microscopy and correlated with the fungicidal activity in the different matrixes. LfcinB(17-31) and LFH showed growth inhibitory properties in wine suggesting their potential use for spoilage control.

  15. Targeting diverse protein-protein interaction interfaces with α/β-peptides derived from the Z-domain scaffold.

    Science.gov (United States)

    Checco, James W; Kreitler, Dale F; Thomas, Nicole C; Belair, David G; Rettko, Nicholas J; Murphy, William L; Forest, Katrina T; Gellman, Samuel H

    2015-04-14

    Peptide-based agents derived from well-defined scaffolds offer an alternative to antibodies for selective and high-affinity recognition of large and topologically complex protein surfaces. Here, we describe a strategy for designing oligomers containing both α- and β-amino acid residues ("α/β-peptides") that mimic several peptides derived from the three-helix bundle "Z-domain" scaffold. We show that α/β-peptides derived from a Z-domain peptide targeting vascular endothelial growth factor (VEGF) can structurally and functionally mimic the binding surface of the parent peptide while exhibiting significantly decreased susceptibility to proteolysis. The tightest VEGF-binding α/β-peptide inhibits the VEGF165-induced proliferation of human umbilical vein endothelial cells. We demonstrate the versatility of this strategy by showing how principles underlying VEGF signaling inhibitors can be rapidly extended to produce Z-domain-mimetic α/β-peptides that bind to two other protein partners, IgG and tumor necrosis factor-α. Because well-established selection techniques can identify high-affinity Z-domain derivatives from large DNA-encoded libraries, our findings should enable the design of biostable α/β-peptides that bind tightly and specifically to diverse targets of biomedical interest. Such reagents would be useful for diagnostic and therapeutic applications.

  16. Targeting diverse protein–protein interaction interfaces with α/β-peptides derived from the Z-domain scaffold

    Energy Technology Data Exchange (ETDEWEB)

    Checco, James W.; Kreitler, Dale F.; Thomas, Nicole C.; Belair, David G.; Rettko, Nicholas J.; Murphy, William L.; Forest, Katrina T.; Gellman, Samuel H. (UW)

    2015-04-14

    Peptide-based agents derived from well-defined scaffolds offer an alternative to antibodies for selective and high-affinity recognition of large and topologically complex protein surfaces. Here, we describe a strategy for designing oligomers containing both α- and β-amino acid residues ("α/β-peptides") that mimic several peptides derived from the three-helix bundle "Z-domain" scaffold. We show that α/β-peptides derived from a Z-domain peptide targeting vascular endothelial growth factor (VEGF) can structurally and functionally mimic the binding surface of the parent peptide while exhibiting significantly decreased susceptibility to proteolysis. The tightest VEGF-binding α/β-peptide inhibits the VEGF₁₆₅-induced proliferation of human umbilical vein endothelial cells. We demonstrate the versatility of this strategy by showing how principles underlying VEGF signaling inhibitors can be rapidly extended to produce Z-domain–mimetic α/β-peptides that bind to two other protein partners, IgG and tumor necrosis factor-α. Because well-established selection techniques can identify high-affinity Z-domain derivatives from large DNA-encoded libraries, our findings should enable the design of biostable α/β-peptides that bind tightly and specifically to diverse targets of biomedical interest. Such reagents would be useful for diagnostic and therapeutic applications.

  17. Extracellular Protein Interactions Mediated by the Neural Cell Adhesion Molecule, NCAM: Heterophilic Interactions Between NCAM and Cell Adhesion Molecules, Extracellular Matrix Proteins, and Viruses

    DEFF Research Database (Denmark)

    Nielsen, Janne; Kulahin, Nikolaj; Walmod, Peter

    2008-01-01

    Cell adhesion molecules (CAMs) mediate cell-to-cell interactions and interactions between cells and the extracellular matrix (ECM). The neural cell adhesion molecule (NCAM), a prototypic member of the immunoglobulin (Ig) superfamily of CAMs, mediates adhesion through homophilic and heterophilic i...

  18. Biodegradable electrospun nanofibers coated with platelet-rich plasma for cell adhesion and proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Diaz-Gomez, Luis [Departamento de Farmacia y Tecnología Farmacéutica, Facultad de Farmacia, Universidad de Santiago de Compostela, 15872 Santiago de Compostela (Spain); Instituto de Ortopedia y Banco de Tejidos Musculoesqueléticos, Universidad de Santiago de Compostela, 15872 Santiago de Compostela (Spain); Alvarez-Lorenzo, Carmen, E-mail: carmen.alvarez.lorenzo@usc.es [Departamento de Farmacia y Tecnología Farmacéutica, Facultad de Farmacia, Universidad de Santiago de Compostela, 15872 Santiago de Compostela (Spain); Concheiro, Angel [Departamento de Farmacia y Tecnología Farmacéutica, Facultad de Farmacia, Universidad de Santiago de Compostela, 15872 Santiago de Compostela (Spain); Silva, Maite [Instituto de Ortopedia y Banco de Tejidos Musculoesqueléticos, Universidad de Santiago de Compostela, 15872 Santiago de Compostela (Spain); Dominguez, Fernando [Fundación Publica Galega de Medicina Xenómica, Santiago de Compostela (Spain); Sheikh, Faheem A.; Cantu, Travis; Desai, Raj; Garcia, Vanessa L. [Department of Chemistry, University of Texas Pan American, Edinburg, TX 78541 (United States); Macossay, Javier, E-mail: jmacossay@utpa.edu [Department of Chemistry, University of Texas Pan American, Edinburg, TX 78541 (United States)

    2014-07-01

    Biodegradable electrospun poly(ε-caprolactone) (PCL) scaffolds were coated with platelet-rich plasma (PRP) to improve cell adhesion and proliferation. PRP was obtained from human buffy coat, and tested on human adipose-derived mesenchymal stem cells (MSCs) to confirm cell proliferation and cytocompatibility. Then, PRP was adsorbed on the PCL scaffolds via lyophilization, which resulted in a uniform sponge-like coating of 2.85 (S.D. 0.14) mg/mg. The scaffolds were evaluated regarding mechanical properties (Young's modulus, tensile stress and tensile strain), sustained release of total protein and growth factors (PDGF-BB, TGF-β1 and VEGF), and hemocompatibility. MSC seeded on the PRP–PCL nanofibers showed an increased adhesion and proliferation compared to pristine PCL fibers. Moreover, the adsorbed PRP enabled angiogenesis features observed as neovascularization in a chicken chorioallantoic membrane (CAM) model. Overall, these results suggest that PRP–PCL scaffolds hold promise for tissue regeneration applications. - Highlights: • Platelet-rich plasma (PRP) can be adsorbed on electrospun fibers via lyophilization. • PRP coating enhanced mesenchymal stem cell adhesion and proliferation on scaffolds. • PRP-coated scaffolds showed sustained release of growth factors. • Adsorbed PRP provided angiogenic features. • PRP-poly(ε-caprolactone) scaffolds hold promise for tissue regeneration applications.

  19. Human Bone Marrow Mesenchymal Stem Cells Regulate Biased DNA Segregation in Response to Cell Adhesion Asymmetry

    Directory of Open Access Journals (Sweden)

    Delphine Freida

    2013-11-01

    Full Text Available Biased DNA segregation is a mitotic event in which the chromatids carrying the original template DNA strands and those carrying the template copies are not segregated randomly into the two daughter cells. Biased segregation has been observed in several cell types, but not in human mesenchymal stem cells (hMSCs, and the factors affecting this bias have yet to be identified. Here, we have investigated cell adhesion geometries as a potential parameter by plating hMSCs from healthy donors on fibronectin-coated micropatterns. On symmetric micropatterns, the segregation of sister chromatids to the daughter cells appeared random. In contrast, on asymmetric micropatterns, the segregation was biased. This sensitivity to asymmetric extracellular cues was reproducible in cells from all donors but was not observed in human skin-derived fibroblasts or in a fibroblastic cell line used as controls. We conclude that the asymmetry of cell adhesion is a major factor in the regulation of biased DNA segregation in hMSCs.

  20. Application of avidin-biotin technology to improve cell adhesion on nanofibrous matrices.

    Science.gov (United States)

    Pan, Jian-feng; Liu, Ning-hua; Shu, Lin-yuan; Sun, Hui

    2015-05-16

    Electrospinning is an easy and effective technique to produce submicron fibers possessing a range of attractive characteristics such as interconnected porous structures similar to natural ECM and good resilience to movement. Rapid and efficient cell attachment to nanofibrous matrices is a necessary prerequisite in tissue engineering. Thus, the aim of this study is to evaluate poly(ε-caprolactone-co-lactide)/Pluronic (PLCL/Pluronic) nanofibrous matrices with avidin-biotin technology for improving cell adhesion for the first time. PLCL/Pluronic nanofibers had relatively homogeneous fibers and interconnected porous structures. Pluronic significantly modified the hydrophilicity of nanofibrous matrices and PLCL/Pluronic nanofibrous matrices had better performance on maintaining cell proliferation. Avidin-biotin technology had no negative effect on the hydrophilic property, mechanical property and cell proliferation. Meanwhile, the attachment and spreading of adipose-derived stem cells (ADSCs) onto PLCL/Pluronic nanofibrous matrices with avidin-biotin technology was promoted obviously. PLCL/Pluronic nanofibrous matrices inheriting the excellent characteristics of both PLCL and Pluronic have the better cell adhesion ability through avidin-biotin technology, implying a promising application in skin care, tissue regeneration and other related area.

  1. The effect of plasma-nitrided titanium surfaces on osteoblastic cell adhesion, proliferation, and differentiation.

    Science.gov (United States)

    Ferraz, Emanuela P; Sa, Juliana C; de Oliveira, Paulo T; Alves, Clodomiro; Beloti, Marcio M; Rosa, Adalberto L

    2014-04-01

    In this study, we evaluated the effect of new plasma-nitrided Ti surfaces on the progression of osteoblast cultures, including cell adhesion, proliferation and differentiation. Ti surfaces were treated using two plasma-nitriding protocols, hollow cathode for 3 h (HC 3 h) and 1 h (HC 1 h) and planar for 1 h. Untreated Ti surfaces were used as control. Cells derived from human alveolar and rat calvarial bones were cultured on Ti surfaces for periods of up to 14 days and the following parameters were evaluated: cell morphology, adhesion, spreading and proliferation, alkaline phosphatase (ALP) activity, extracellular matrix mineralization, and gene expression of key osteoblast markers. Plasma-nitriding treatments resulted in Ti surfaces with distinct physicochemical characteristics. The cell adhesion and ALP activity were higher on plasma-nitrided Ti surfaces compared with untreated one, whereas cell proliferation and extracellular matrix mineralization were not affected by the treatments. In addition, the plasma-nitrided Ti surfaces increased the ALP, reduced the osteocalcin and did not affect the Runx2 gene expression. We have shown that HC 3 h and planar Ti surfaces slightly favored the osteoblast differentiation process, and then these surfaces should be considered for further investigation using preclinical models. Copyright © 2013 Wiley Periodicals, Inc.

  2. Purification and characterisation of antibacterial peptide-containing compound derived from palm kernel cake.

    Science.gov (United States)

    Tan, Yen Nee; Ayob, Mohd Khan; Wan Yaacob, Wan Ahmad

    2013-01-01

    Palm kernel cake (PKC), the most useful by-product resulted from palm kernel oil production. In this study, PKC-derived protein product was found suitable for use as an antimicrobial agent with potent antibacterial activity, particularly against Bacillus species, after enzymatic hydrolysis with alcalase. The hydrolysate was further purified by gel filtration chromatography. The purified fraction was found to have 14.63±0.70% (w/w) protein, a molecular mass of 2.4kDa and low hemolytic activity (antibacterial effect of purified PKC fraction. This study suggests that the antibacterial PKC compound may be not a pure peptide but instead a peptide-containing compound high in lauric acid derivative.

  3. Dendritic-tumor fusion cells derived heat shock protein70-peptide complex has enhanced immunogenicity.

    Science.gov (United States)

    Zhang, Yunfei; Zhang, Yong; Chen, Jun; Liu, Yunyan; Luo, Wen

    2015-01-01

    Tumor-derived heat shock protein70-peptide complexes (HSP70.PC-Tu) have shown great promise in tumor immunotherapy due to numerous advantages. However, large-scale phase III clinical trials showed that the limited immunogenicity remained to be enhanced. In previous research, we demonstrated that heat shock protein 70-peptide complexes (HSP70.PC-Fc) derived from dendritic cell (DC)-tumor fusions exhibit enhanced immunogenicity compared with HSP70.PCs from tumor cells. However, the DCs used in our previous research were obtained from healthy donors and not from the patient population. In order to promote the clinical application of these complexes, HSP70.PC-Fc was prepared from patient-derived DC fused directly with patient-derived tumor cells in the current study. Our results showed that compared with HSP70.PC-Tu, HSP70.PC-Fc elicited much more powerful immune responses against the tumor from which the HSP70 was derived, including enhanced T cell activation, and CTL responses that were shown to be antigen specific and HLA restricted. Our results further indicated that the enhanced immunogenicity is related to the activation of CD4+ T cells and increased association with other heat shock proteins, such as HSP90. Therefore, the current study confirms the enhanced immunogenicity of HSP70.PC derived from DC-tumor fusions and may provide direct evidence promoting their future clinical use.

  4. A Review of Cell Adhesion Studies for Biomedical and Biological Applications

    Directory of Open Access Journals (Sweden)

    Amelia Ahmad Khalili

    2015-08-01

    Full Text Available Cell adhesion is essential in cell communication and regulation, and is of fundamental importance in the development and maintenance of tissues. The mechanical interactions between a cell and its extracellular matrix (ECM can influence and control cell behavior and function. The essential function of cell adhesion has created tremendous interests in developing methods for measuring and studying cell adhesion properties. The study of cell adhesion could be categorized into cell adhesion attachment and detachment events. The study of cell adhesion has been widely explored via both events for many important purposes in cellular biology, biomedical, and engineering fields. Cell adhesion attachment and detachment events could be further grouped into the cell population and single cell approach. Various techniques to measure cell adhesion have been applied to many fields of study in order to gain understanding of cell signaling pathways, biomaterial studies for implantable sensors, artificial bone and tooth replacement, the development of tissue-on-a-chip and organ-on-a-chip in tissue engineering, the effects of biochemical treatments and environmental stimuli to the cell adhesion, the potential of drug treatments, cancer metastasis study, and the determination of the adhesion properties of normal and cancerous cells. This review discussed the overview of the available methods to study cell adhesion through attachment and detachment events.

  5. Glycosylation inhibitors efficiently inhibit P-selectin-mediated cell adhesion to endothelial cells.

    Science.gov (United States)

    Ghoshal, Pushpankur; Rajendran, Mythilypriya; Odo, Nadine; Ikuta, Tohru

    2014-01-01

    Adhesion molecules play a critical role in the adhesive interactions of multiple cell types in sickle cell disease (SCD). We previously showed that anti-P-selectin aptamer efficiently inhibits cell adhesion to endothelial cells (ECs) and permits SCD mice to survive hypoxic stress. In an effort to discover new mechanisms with which to inhibit P-selectin, we examined the role of glycosylation. P-selectin is a 90 kDa protein but was found to migrate as 90 and 140 kDa bands on gel electrophoresis. When P-selectin isolated from ECs was digested with peptide N-glycosidase F, but not O-glycosidase, the 140 kDa band was lost and the 90 kDa band was enhanced. Treatment of ECs with tunicamycin, an N-glycosylation inhibitor, suppressed CD62P (P-selectin) expression on the cell surface as well as the 140 kDa form in the cytoplasm. These results indicate that the 140 kDa band is N-glycosylated and glycosylation is critical for cell surface expression of P-selectin in ECs. Thrombin, which stimulates P-selectin expression on ECs, induced AKT phosphorylation, whereas tunicamycin inhibited AKT phosphorylation, suggesting that AKT signaling is involved in the tunicamycin-mediated inhibition of P-selectin expression. Importantly, the adhesion of sickle red blood cells (sRBCs) and leukocytes to ECs induced by thrombin or hypoxia was markedly inhibited by two structurally distinct glycosylation inhibitors; the levels of which were comparable to that of a P-selectin monoclonal antibody which most strongly inhibited cell adhesion in vivo. Knockdown studies of P-selectin using short-hairpin RNAs in ECs suppressed sRBC adhesion, indicating a legitimate role for P-selectin in sRBC adhesion. Together, these results demonstrate that P-selectin expression on ECs is regulated in part by glycosylation mechanisms and that glycosylation inhibitors efficiently reduce the adhesion of sRBCs and leukocytes to ECs. Glycosylation inhibitors may lead to a novel therapy which inhibits cell adhesion in SCD.

  6. Design of Ligands for Affinity Purification of G-CSF Based on Peptide Ligands Derived from a Peptide Library

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Combinatorial peptide libraries have become powerful tools to screen functional ligands by the principle of affinity selection. We screened in a phage peptide library to investigate potential peptide affinity ligands for the purification of human granulocyte colony-stimulation factor(hG-CSF). Peptide ligands will be promising to replace monoclonal antibodies as they have advantages of high stability, efficiency, selectivity and low price.

  7. Single cell adhesion assay using computer controlled micropipette.

    Directory of Open Access Journals (Sweden)

    Rita Salánki

    Full Text Available Cell adhesion is a fundamental phenomenon vital for all multicellular organisms. Recognition of and adhesion to specific macromolecules is a crucial task of leukocytes to initiate the immune response. To gain statistically reliable information of cell adhesion, large numbers of cells should be measured. However, direct measurement of the adhesion force of single cells is still challenging and today's techniques typically have an extremely low throughput (5-10 cells per day. Here, we introduce a computer controlled micropipette mounted onto a normal inverted microscope for probing single cell interactions with specific macromolecules. We calculated the estimated hydrodynamic lifting force acting on target cells by the numerical simulation of the flow at the micropipette tip. The adhesion force of surface attached cells could be accurately probed by repeating the pick-up process with increasing vacuum applied in the pipette positioned above the cell under investigation. Using the introduced methodology hundreds of cells adhered to specific macromolecules were measured one by one in a relatively short period of time (∼30 min. We blocked nonspecific cell adhesion by the protein non-adhesive PLL-g-PEG polymer. We found that human primary monocytes are less adherent to fibrinogen than their in vitro differentiated descendants: macrophages and dendritic cells, the latter producing the highest average adhesion force. Validation of the here introduced method was achieved by the hydrostatic step-pressure micropipette manipulation technique. Additionally the result was reinforced in standard microfluidic shear stress channels. Nevertheless, automated micropipette gave higher sensitivity and less side-effect than the shear stress channel. Using our technique, the probed single cells can be easily picked up and further investigated by other techniques; a definite advantage of the computer controlled micropipette. Our experiments revealed the existence of a

  8. Biomechanics of P-selectin PSGL-1 bonds: Shear threshold and integrin-independent cell adhesion

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Zhihua; Goldsmith, Harry L.; MacIntosh, Fiona A.; Shankaran, Harish; Neelamegham, Sriram

    2006-03-01

    Platelet-leukocyte adhesion may contribute to thrombosis and inflammation. We examined the heterotypic interaction between unactivated neutrophils and either thrombin receptor activating peptide (TRAP) stimulated platelets or P-selectin bearing beads (Ps-beads) in suspension. Cone-plate viscometers were used to apply controlled shear rates from 14-3000/s. Platelet-neutrophil and bead-neutrophil adhesion analysis was performed using both flow cytometry and high-speed videomicroscopy. We observed that while blocking antibodies against either P-selectin or P-selectin glycoprotein ligand-1 (PSGL-1) alone inhibited platelet-neutrophil adhesion by ~60% at 140/s, these reagents completely blocked adhesion at 3000/s. Anti-Mac-1 alone did not alter platelet-neutrophil adhesion rates at any shear rate, though in synergy with selectin antagonists it abrogated cell binding. Unstimulated neutrophils avidly bound Ps-beads and activated platelets in an integrin-independent manner, suggesting that purely selectin-dependent cell adhesion is possible. In support of this, antagonists against P-selectin or PSGL-1 dissociated previously formed platelet-neutrophil and Ps-bead neutrophil aggregates under shear in a variety of experimental systems, including in assays performed with whole blood. In studies where medium viscosity and shear rate were varied, a subtle shear threshold for P-selectin PSGL-1 binding was also noted at shear rates<100/s and at force loading rates of ~300pN/sec. Results are discussed in light of biophysical computations that characterize the collision between unequal size particles in linear shear flow. Overall, our studies reveal an integrin-independent regime for cell adhesion that may be physiologically relevant.

  9. Cadherin Cell Adhesion System in Canine Mammary Cancer: A Review

    Directory of Open Access Journals (Sweden)

    Adelina Gama

    2012-01-01

    Full Text Available Cadherin-catenin adhesion complexes play important roles by providing cell-cell adhesion and communication in different organ systems. Abnormal expression of cadherin adhesion molecules constitutes a common phenomenon in canine mammary cancer and has been frequently implicated in tumour progression. This paper summarizes the current knowledge on cadherin/catenin adhesion molecules (E-cadherin, β-catenin, and P-cadherin in canine mammary cancer, focusing on the putative biological functions and clinical significance of these molecules in this disease. This paper highlights the need for further research studies in this setting in order to elucidate the role of these adhesion molecules during tumour progression and metastasis.

  10. Synthesis and Biological Activity of Peptide Derivatives of Iodoquinazolinones/Nitroimidazoles

    Directory of Open Access Journals (Sweden)

    Rakesh Yadav

    2008-04-01

    Full Text Available Two substituted quinazolinyl/imidazolyl-salicylic acids 5, 6 were synthesized bythe reaction of 6-iodo-2-methylbenzoxazin-4-one/5-nitroimidazole with 5-aminosalicylicacid (5-ASA. Coupling of compounds 5 and 6 with different amino acid esterhydrochlorides, dipeptide and tripeptide methyl esters yielded novelquinazolino/imidazolopeptide derivatives 5a-f and 6a-g. The chemical structures of allnewly synthesized compounds were confirmed by means of FT-IR, 1H- and 13C-NMR, MSand elemental analysis. Selected peptide ester derivatives were further hydrolyzed by usinglithium hydroxide (LiOH to afford the corresponding acid derivatives 5ba-da and 6ea-ga.All peptide derivatives were assayed for antimicrobial and anthelmintic activities againsteight pathogenic microbes and three earthworm species. Among the tested compounds, 5e,5d, 6e and their hydrolyzed analogs 5da and 6ea exhibited higher antimicrobial activityagainst Pseudomonas aeruginosa, Klebsiella pneumoniae and Candida albicans, and 5a,6g and 6ga displayed better antifungal activity against the dermatophytes Trichophytonmentagrophytes and Microsporum audouinii. Moreover, 6f and its hydrolyzed derivative6fa showed good anthelmintic activity against Megascoplex konkanensis, Pontoscotexcorethruses and Eudrilus eugeniea at dose of 2 mg mL–1.

  11. Milk-derived proteins and peptides of potential therapeutic and nutritive value.

    Science.gov (United States)

    Zimecki, Michal; Kruzel, Marian L

    2007-01-01

    Milk and colostrum are rich in proteins and peptides which play a crucial role in development of the immune system in mammalian offspring. Immunotropic properties of these compounds prompted investigators to search for their utility in prevention and therapy of various disorders in humans. The following constituents of milk are of particular interest: 1) Lactoferrin (LF)--exhibits antibacterial, antifungal, antiviral, antiparasite and antitumor activities. It is protective with regard to intestinal epithelium, promotes bone growth and accelerates recovery of the immune system function in immunocompromised animal; 2) A Proline-Rich Polypeptide (PRP) shows a variety of immunotropic functions, including promotion of T-cell maturation and inhibition'of autoimmune disorders. PRP was recently found to improve or stabilize the Instrumental Activity of Daily Living status in Alzheimer's disease patients. 3) Casein--has been protective in experimental bacteremia by eliciting myelopoiesis. Casein hydrolyzates were also protective in diabetic animals, reduced the tumor growth and diminished colicky symptoms in infants. Casein-derived peptides have been found to have antihypertensive effects. Glycomacropeptide (GMP)--a peptide derived from kappa casein, exhibits antibacterial and antithrombotic activities. 4) Alpha lactalbumin (LA)--demonstrates antiviral, antitumor and anti-stress properties. LA-enriched diets were anxiolytic, lowered blood pressure in rats, prevented diarrhea and led to a better weight gain in malnourished children. 5) Lysozyme--is effective in treatment of periodentitis and prevention of tooth decay. Milk enriched in lysozyme was used in feeding premature infants suffering from concomitant diseases. 6) Lactoperoxidase--shows antibacterial properties. In conclusion, milk-derived proteins and peptides are bio-accessible and safe for the prevention and treatment of numerous disorders in humans.

  12. Hexokinase II-derived cell-penetrating peptide targets mitochondria and triggers apoptosis in cancer cells.

    Science.gov (United States)

    Woldetsadik, Abiy D; Vogel, Maria C; Rabeh, Wael M; Magzoub, Mazin

    2017-05-01

    Overexpression of mitochondria-bound hexokinase II (HKII) in cancer cells plays an important role in their metabolic reprogramming and protects them against apoptosis, thereby facilitating their growth and proliferation. Here, we show that covalently coupling a peptide corresponding to the mitochondrial membrane-binding N-terminal 15 aa of HKII (pHK) to a short, penetration-accelerating sequence (PAS) enhances the cellular uptake, mitochondrial localization, and cytotoxicity of the peptide in HeLa cells. Further analysis revealed that pHK-PAS depolarized mitochondrial membrane potential, inhibited mitochondrial respiration and glycolysis, and depleted intracellular ATP levels. The effects of pHK-PAS were correlated with dissociation of endogenous full-length HKII from mitochondria and release of cytochrome c Of significance, pHK-PAS treatment of noncancerous HEK293 cells resulted in substantially lower cytotoxicity. Thus, pHK-PAS effectively disrupted the mitochondria-HKII association in cancer cells, which led to mitochondrial dysfunction and, finally, apoptosis. Our results demonstrate the potential of the pHK-PAS cell-penetrating peptide as a novel therapeutic strategy in cancer.-Woldetsadik, A. D., Vogel, M. C., Rabeh, W. M., Magzoub, M. Hexokinase II-derived cell-penetrating peptide targets mitochondria and triggers apoptosis in cancer cells. © The Author(s).

  13. Synthetic peptides derived from ribosomal proteins of Leishmania spp. in mucocutaneous leishmaniasis: Diagnostic usefulness.

    Science.gov (United States)

    Florez, Magda Melissa; de Oliveira, Camila Indiani; Puerta, Concepción; Guzmán, Fanny; Ayala, Martha; Montoya, Gladis; Delgado, Gabriela

    2017-07-28

    The serological diagnostic methods currently available for mucocutaneous leishmaniasis (MCL) lack specificity when complete parasites are used; however, such specificity increases when protein fractions are used. Ribosomal proteins have been reported to induce antibodies in animal and humans infected with the parasite, making them a worth candidate to assess its diagnosis potential. This study was thus aimed at evaluating synthetic peptides derived from Leishmania braziliensis ribosomal proteins S25 and S5 as antigen candidates for diagnosing MCL by ELISA; 4 of these 21 peptides (P4, P6, P19 and P21) had the greatest sensitivity (21.7%, 13.04%, 20% and 20%, respectively) as well as having 95%, 100%, 100% and 82.5% specificity, respectively. The study revealed the limited usefulness of the peptides being studied as a diagnostic tool in the conditions used here, because its low sensitivity, but it is worth highlighting that the use of peptides as antigen in the serodiagnosis of MCL may overcome the cross reaction presented with other antigens, thus avoiding false positives. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  14. The TFPI-2 derived peptide EDC34 improves outcome of gram-negative sepsis.

    Directory of Open Access Journals (Sweden)

    Praveen Papareddy

    Full Text Available Sepsis is characterized by a dysregulated host-pathogen response, leading to high cytokine levels, excessive coagulation and failure to eradicate invasive bacteria. Novel therapeutic strategies that address crucial pathogenetic steps during infection are urgently needed. Here, we describe novel bioactive roles and therapeutic anti-infective potential of the peptide EDC34, derived from the C-terminus of tissue factor pathway inhibitor-2 (TFPI-2. This peptide exerted direct bactericidal effects and boosted activation of the classical complement pathway including formation of antimicrobial C3a, but inhibited bacteria-induced activation of the contact system. Correspondingly, in mouse models of severe Escherichia coli and Pseudomonas aeruginosa infection, treatment with EDC34 reduced bacterial levels and lung damage. In combination with the antibiotic ceftazidime, the peptide significantly prolonged survival and reduced mortality in mice. The peptide's boosting effect on bacterial clearance paired with its inhibiting effect on excessive coagulation makes it a promising therapeutic candidate for invasive Gram-negative infections.

  15. The Toxicity of a Chemically Synthesized Peptide Derived from Non-Integrin Platelet Collagen Receptors

    Directory of Open Access Journals (Sweden)

    Thomas M. Chiang

    2008-01-01

    Full Text Available A chemically synthesized peptide derived from platelet non-integrin collagen receptor has been shown to be an effective agent for inhibiting collagen-induced platelet aggregation and adhesion of washed radiolabeled platelets onto natural matrices and collagen coated microtiter plates. In order to be a therapeutic agent, we have used a cell culturing system and an animal model to test its cytotoxicities. In cell culture experiments, the peptide is not toxic to MEG-01, a megakaryoblastic cell line. Prior to performing experiments in rats, the existence of both platelet type I and type III collagen receptors and its functional roles in rat platelets had to be established. In this investigation, we report that rat platelets contain both receptors and the cHyB peptide inhibits both type I and type III collagen-induced rat platelet aggregation. In addition, analysis of the rat sera collected at various time intervals following an injection of cHyB into the rat-tail vein, did not show an increase in the activity of key enzymes which indicate tissue and/or organ damage. These results suggest that the cHyB peptide is safe and its development into a potential therapeutic agent for inhibiting thrombi formation is possible.

  16. The Toxicity of a Chemically Synthesized Peptide Derived from Non-Integrin Platelet Collagen Receptors

    Directory of Open Access Journals (Sweden)

    Thomas M. Chiang

    2008-08-01

    Full Text Available A chemically synthesized peptide derived from platelet non-integrin collagen receptor has been shown to be an effective agent for inhibiting collagen-induced platelet aggregation and adhesion of washed radiolabeled platelets onto natural matrices and collagen coated microtiter plates. In order to be a therapeutic agent, we have used a cell culturing system and an animal model to test its cytotoxicities. In cell culture experiments, the peptide is not toxic to MEG-01, a megakaryoblastic cell line. Prior to performing experiments in rats, the existence of both platelet type I and type III collagen receptors and its functional roles in rat platelets had to be established. In this investigation, we report that rat platelets contain both receptors and the cHyB peptide inhibits both type I and type III collagen-induced rat platelet aggregation. In addition, analysis of the rat sera collected at various time intervals following an injection of cHyB into the rat-tail vein, did not show an increase in the activity of key enzymes which indicate tissue and/or organ damage. These results suggest that the cHyB peptide is safe and its development into a potential therapeutic agent for inhibiting thrombi formation is possible.

  17. Buforins: histone H2A-derived antimicrobial peptides from toad stomach.

    Science.gov (United States)

    Cho, Ju Hyun; Sung, Bong Hyun; Kim, Sun Chang

    2009-08-01

    Antimicrobial peptides (AMPs) constitute an important component of the innate immune system in a variety of organisms. Buforin I is a 39-amino acid AMP that was first isolated from the stomach tissue of the Asian toad Bufo bufo gargarizans. Buforin II is a 21-amino acid peptide that is derived from buforin I and displays an even more potent antimicrobial activity than its parent AMP. Both peptides share complete sequence identity with the N-terminal region of histone H2A that interacts directly with nucleic acids. Buforin I is generated from histone H2A by pepsin-directed proteolysis in the cytoplasm of gastric gland cells. After secretion into the gastric lumen, buforin I remains adhered to the mucous biofilm that lines the stomach, thus providing a protective antimicrobial coat. Buforins, which house a helix-hinge-helix domain, kill a microorganism by entering the cell without membrane permeabilization and thus binding to nucleic acids. The proline hinge is crucial for the cell penetrating activity of buforins. Buforins also are known to possess anti-endotoxin and anticancer activities, thus making these peptides attractive reagents for pharmaceutical applications. This review describes the role of buforins in innate host defense; future research paradigms; and use of these agents as human therapeutics.

  18. MHC class II-derived peptides can bind to class II molecules, including self molecules, and prevent antigen presentation

    DEFF Research Database (Denmark)

    Rosloniec, E F; Vitez, L J; Buus, S

    1990-01-01

    found in the first and third polymorphic regions (PMR) of the A alpha k chain (alpha k-1 and alpha k-3) were capable of inhibiting the presentation of three different HEL-derived peptide antigens to their appropriate T cells. In addition, the alpha k-1 peptide inhibited the presentation of the OVA(323......-339) immunodominant peptide to the I-Ad-restricted T cell hybridomas specific for it. Prepulsing experiments demonstrated that the PMR peptides were interacting with the APC and not with the T cell hybridomas. These observations were confirmed and extended by the demonstration that the alpha k-1 and alpha k-3...

  19. [Molecular basis of red blood cell adhesion to endothelium].

    Science.gov (United States)

    Wautier, J-L; Wautier, M-P

    2011-01-01

    The extent of red blood cell adhesion is correlated with the incidence of vascular complications and the severity of the disease. Patients with sickle cell anemia (HbSS) experience vasoocclusive episodes. The adhesion of RBCs from HbSS patients is increased and related to VLA-4 exposure, which binds to vascular cell adhesion molecule (VCAM-1). Inter Cellular Adhesion Molecule (ICAM-1), CD31, CD36 and glycans are potential receptors for PfEMP1 of RBCs parasited by plasmodium falciparum. The incidence of vascular complications is very high in patients with diabetes mellitus. RBC adhesion is increased and statistically correlated with the severity of the angiopathy. Glycation of RBC membrane proteins is responsible for binding to the receptor for advanced glycation end products (RAGE). Polycythemia Vera (PV) is the most frequent myeloproliferative disorder and characterized by a high occurrence of thrombosis of mesenteric and cerebral vessels. PV is due to a mutation of the Janus kinase 2 (JAK2 V617F). This mutation stimulates erythropoiesis and is the cause of Lu/BCAM (CD239) phosphorylation, which potentiated the interaction with laminin alpha 5. The couple laminin alpha 5 endothelial and phosphorylated Lu/BCAM explained the increased adhesion of RBCs from patients PV to endothelium.

  20. Friction-controlled traction force in cell adhesion.

    Science.gov (United States)

    Pompe, Tilo; Kaufmann, Martin; Kasimir, Maria; Johne, Stephanie; Glorius, Stefan; Renner, Lars; Bobeth, Manfred; Pompe, Wolfgang; Werner, Carsten

    2011-10-19

    The force balance between the extracellular microenvironment and the intracellular cytoskeleton controls the cell fate. We report a new (to our knowledge) mechanism of receptor force control in cell adhesion originating from friction between cell adhesion ligands and the supporting substrate. Adherent human endothelial cells have been studied experimentally on polymer substrates noncovalently coated with fluorescent-labeled fibronectin (FN). The cellular traction force correlated with the mobility of FN during cell-driven FN fibrillogenesis. The experimental findings have been explained within a mechanistic two-dimensional model of the load transfer at focal adhesion sites. Myosin motor activity in conjunction with sliding of FN ligands noncovalently coupled to the surface of the polymer substrates is shown to result in a controlled traction force of adherent cells. We conclude that the friction of adhesion ligands on the supporting substrate is important for mechanotransduction and cell development of adherent cells in vitro and in vivo. Copyright © 2011 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  1. Effect of hydroxyapatite surface morphology on cell adhesion.

    Science.gov (United States)

    Iwamoto, Takashi; Hieda, Yohki; Kogai, Yasumichi

    2016-12-01

    We obtained hydroxyapatite (HAp) materials as a block by mixing HAp nanoparticles and polymer, and then calcining the mixtures. The surface morphology of the HAp materials was tuned by varying heat treatment conditions. After calcining the mixtures at 1200 or 800°C for 4h, the surface morphology of the HAp materials was flat or convexo-concave, respectively. The flat surface morphology, which showed micrometer-ordered grain boundaries, was formed by the aggregation of HAp nanoparticles. On the other hand, the convexo-concave surface morphology resulted from the agglomeration of HAp nanoparticles after heat treatment at 800°C for 4h with nanometer-ordered particle size. We tested cell adhesion to HAp materials with flat or convexo-concave surface morphology and found that cells adhered well to the flat HAp materials but not to the convexo-concave HAp materials. This technique for selectively preparing HAp materials with flat or convexo-concave surface morphology was very easy because we merely mixed commercial HAp nanoparticles with polymer and then calcined the mixtures. As a result, the heat treatment temperature affected the surface morphology of our HAp materials, and their surface morphologies contributed to cell adhesion independently of other material properties.

  2. How to let go: pectin and plant cell adhesion

    Science.gov (United States)

    Daher, Firas Bou; Braybrook, Siobhan A.

    2015-01-01

    Plant cells do not, in general, migrate. They maintain a fixed position relative to their neighbors, intimately linked through growth and differentiation. The mediator of this connection, the pectin-rich middle lamella, is deposited during cell division and maintained throughout the cell’s life to protect tissue integrity. The maintenance of adhesion requires cell wall modification and is dependent on the actin cytoskeleton. There are developmental processes that require cell separation, such as organ abscission, dehiscence, and ripening. In these instances, the pectin-rich middle lamella must be actively altered to allow cell separation, a process which also requires cell wall modification. In this review, we will focus on the role of pectin and its modification in cell adhesion and separation. Recent insights gained in pectin gel mechanics will be discussed in relation to existing knowledge of pectin chemistry as it relates to cell adhesion. As a whole, we hope to begin defining the physical mechanisms behind a cells’ ability to hang on, and how it lets go. PMID:26236321

  3. How to let go: pectin and plant cell adhesion

    Directory of Open Access Journals (Sweden)

    Firas eBou Daher

    2015-07-01

    Full Text Available Plant cells do not, in general, migrate. They maintain a fixed position relative to their neighbours, intimately linked through growth and differentiation. The mediator of this connection, the pectin-rich middle lamella, is deposited during cell division and maintained throughout the cell’s life to protect tissue integrity. The maintenance of adhesion requires cell wall modification and is dependent on the actin cytoskeleton. There are developmental processes that require cell separation, such as organ abscission, dehiscence, and ripening. In these instances, the pectin-rich middle lamella must be actively altered to allow cell separation, a process which also requires cell wall modification. In this review, we will focus on the role of pectin and its modification in cell adhesion and separation. Recent insights gained in pectin gel mechanics will be discussed in relation to existing knowledge of pectin chemistry as it relates to cell adhesion. As a whole, we hope to begin defining the physical mechanisms behind a cells’ ability to hang on, and how it lets go.

  4. Cell Adhesion on Polycaprolactone Modified by Plasma Treatment

    Directory of Open Access Journals (Sweden)

    Nina Recek

    2016-01-01

    Full Text Available We have investigated the influence of various plasma treatments of electrospun polycaprolactone (PCL scaffolds on the adhesion and proliferation of human umbilical endothelial cells (HUVEC. The PCL scaffolds were treated in plasmas created in O2, NH3 or SO2 gas at identical conditions. Surface functionalization of plasma-treated samples was determined using X-ray photoelectron spectroscopy. Cell adhesion and morphology were investigated by scanning electron microscopy and the influence of plasma treatment on cell adhesion and viability was evaluated with cell viability assay (MTT assay. The results showed the highest metabolic activity of HUVEC on PCL samples treated with O2 and NH3 plasma. Accordingly, the cells reflected the best adhesion and morphology on O2 and NH3 plasma-treated PCL samples already at 3 h. Moreover, treatment with O2 and NH3 plasma even stimulated endothelial cell proliferation on PCL surfaces by 60% as measured at 24 h, showing significant improvement in endothelialization of this material. Contrarily, SO2 plasma appeared to be less promising in comparison with O2 and NH3 plasma; however, it was still better than without any plasma treatment. Thus, our results importantly contribute to the biocompatibility improvement of the PCL polymer, commonly used for scaffolds in tissue engineering.

  5. Cell adhesion in the process of asexual reproduction of tunicates.

    Science.gov (United States)

    Kawamura, K; Sugino, Y M

    1999-02-15

    Cell adhesion during budding of tunicates is reviewed from the viewpoints of histology, cytology, biochemistry, and molecular biology. Two kinds of multipotent cells play important roles in bud formation and development: epithelial cells, such as the atrial epithelium of botryllids and polystyelids, and mesenchymal cells, referred to as haemoblasts. Haemoblasts are able to aggregate to form a solid mass of cells, which soon becomes a hollow vesicle. The vesicular epithelium has junctional complexes that contain adherens junctions, and, sometimes, tight junctions; both occur apicolaterally on the plasma membrane. The hollow vesicle develops into the heart, the pyloric gland and duct, the gonad, including germ cells, and even the multipotent epithelium of buds. Cell culture studies suggest that multipotent epithelial cells may be interchangeable with haemoblasts. Several kinds of calcium-dependent, galactose-binding tunicate lectins (TC-14s) have been isolated and sequenced, and have been found to facilitate both in vivo and in vitro cell aggregation and migration. Tunicate homologs of cadherin and integrin genes have recently been isolated from Botryllus and Polyandrocarpa, respectively. Their unique molecular characteristics are discussed in the context of roles that they play in cell adhesion in the process of tunicate budding.

  6. [Amino acid and peptide derivatives of the tylosin family of macrolide antibiotics modified at the aldehyde group].

    Science.gov (United States)

    Sumbatian, N V; Kuznetsova, I V; Karpenko, V V; Fedorova, N V; Chertkov, V A; Korshunova, G A; Bogdanov, A A

    2010-01-01

    Fourteen new functionally active amino acid and peptide derivatives of the antibiotics tylosin, desmycosin, and 5-O-mycaminosyltylonolide were synthesized in order to study the interaction of the growing polypeptide chain with the ribosomal tunnel. The conjugation of various amino acids and peptides with a macrolide aldehyde group was carried out by two methods: direct reductive amination with the isolation of the intermediate Schiff bases or through binding via oxime using the preliminarily obtained derivatives of 2-aminooxyacetic acid.

  7. Peptides derived from HIV-1 integrase that bind Rev stimulate viral genome integration.

    Directory of Open Access Journals (Sweden)

    Aviad Levin

    Full Text Available BACKGROUND: The human immunodeficiency virus type 1 (HIV-1 integrase protein (IN, catalyzes the integration of viral DNA into the host cell genome. IN catalyzes the first step of the integration process, namely the 3'-end processing in which IN removes a pGT dinucleotide from the 3' end of each viral long terminal repeat (LTR. Following nuclear import of the viral preintegration complex, the host chromosomal DNA becomes accessible to the viral cDNA and the second step of the integration process, namely the strand-transfer step takes place. This ordered sequence of events, centered on integration, is mandatory for HIV replication. METHODOLOGY/PRINCIPAL FINDINGS: Using an integrase peptide library, we selected two peptides, designated INr-1 and INr-2, which interact with the Rev protein and probably mediate the Rev-integrase interaction. Using an in-vitro assay system, we show that INr-1 and INr-2 are able to abrogate the inhibitory effects exerted by Rev and Rev-derived peptides on integrase activity. Both INr-1 and INr-2 were found to be cell-permeable and nontoxic, allowing a study of their effect in HIV-1-infected cultured cells. Interestingly, both INr peptides stimulated virus infectivity as estimated by production of the viral P24 protein, as well as by determination of the appearance of newly formed virus particles. Furthermore, kinetics studies revealed that the cell-permeable INr peptides enhance the integration process, as was indeed confirmed by direct determination of viral DNA integration by real-time PCR. CONCLUSIONS/SIGNIFICANCE: The results of the present study raise the possibility that in HIV-infected cells, the Rev protein may be involved in the integration of proviral DNA by controlling/regulating the activity of the integrase. Release from such inhibition leads to stimulation of IN activity and multiple viral DNA integration events.

  8. Quantitative comparison of cancer and normal cell adhesion using organosilane monolayer templates: an experimental study on the anti-adhesion effect of green-tea catechins.

    Science.gov (United States)

    Sakamoto, Rumi; Kakinuma, Eisuke; Masuda, Kentaro; Takeuchi, Yuko; Ito, Kosaku; Iketaki, Kentaro; Matsuzaki, Takahisa; Nakabayashi, Seiichiro; Yoshikawa, Hiroshi Y; Yamamoto, Hideaki; Sato, Yuko; Tanii, Takashi

    2016-09-01

    The main constituent of green tea, (-)-Epigallocatechin-3-O-gallate (EGCG), is known to have cancer-specific chemopreventive effects. In the present work, we investigated how EGCG suppresses cell adhesion by comparing the adhesion of human pancreatic cancer cells (AsPC-1 and BxPC-3) and their counterpart, normal human embryonic pancreas-derived cells (1C3D3), in catechin-containing media using organosilane monolayer templates (OMTs). The purpose of this work is (1) to evaluate the quantitativeness in the measurement of cell adhesion with the OMT and (2) to show how green-tea catechins suppress cell adhesion in a cancer-specific manner. For the first purpose, the adhesion of cancer and normal cells was compared using the OMT. The cell adhesion in different type of catechins such as EGCG, (-)-Epicatechin-3-O-gallate (ECG) and (-)-Epicatechin (EC) was also evaluated. The measurements revealed that the anti-adhesion effect of green-tea catechins is cancer-specific, and the order is EGCG≫ECG>EC. The results agree well with the data reported to date, showing the quantitativeness of the new method. For the second purpose, the contact area of cells on the OMT was measured by reflection interference contrast microscopy. The cell-OMT contact area of cancer cells decreases with increasing EGCG concentration, whereas that of normal cells remains constant. The results reveal a twofold action of EGCG on cancer cell adhesion-suppressing cell attachment to a candidate adhesion site and decreasing the contact area of the cells-and validates the use of OMT as a tool for screening cancer cell adhesion.

  9. Amyloid fibril formation of peptides derived from the C-terminus of CETP modulated by lipids

    Energy Technology Data Exchange (ETDEWEB)

    García-González, Victor [Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, 04510 México, DF (Mexico); Mas-Oliva, Jaime, E-mail: jmas@ifc.unam.mx [Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, 04510 México, DF (Mexico); División de Investigación, Facultad de Medicina, Universidad Nacional Autónoma de México, 04510 México, DF (Mexico)

    2013-04-26

    Highlights: •The secondary structure of a C-terminal peptide derived from CETP was studied. •Lipids modulate secondary structure changes of a C-terminal peptide derived from CETP. •Lysophosphatidic acid maintains a functional α-helix and prevents fibril formation. •Transfer of lipids by CETP is related to the presence of an α-helix at its C-end. -- Abstract: Cholesteryl-ester transfer protein (CETP) is a plasmatic protein involved in neutral lipid transfer between lipoproteins. Focusing on the last 12 C-terminus residues we have previously shown that mutation D{sub 470}N promotes a conformational change towards a β-secondary structure. In turn, this modification leads to the formation of oligomers and fibrillar structures, which cause cytotoxic effects similar to the ones provoked by amyloid peptides. In this study, we evaluated the role of specific lipid arrangements on the structure of peptide helix-Z (D{sub 470}N) through the use of thioflavin T fluorescence, peptide bond absorbance, circular dichroism and electron microscopy. The results indicate that the use of micelles formed with lysophosphatidylcholine and lysophosphatidic acid (LPA) under neutral pH induce a conformational transition of peptide helix-Z containing a β-sheet conformation to a native α-helix structure, therefore avoiding the formation of amyloid fibrils. In contrast, incubation with phosphatidic acid does not change the profile for the β-sheet conformation. When the electrostatic charge at the surface of micelles or vesicles is regulated through the use of lipids such as phospholipid and LPA, minimal changes and the presence of β-structures were recorded. Mixtures with a positive net charge diminished the percentage of β-structure and the amount of amyloid fibrils. Our results suggest that the degree of solvation determined by the presence of a free hydroxyl group on lipids such as LPA is a key condition that can modulate the secondary structure and the consequent formation of

  10. [The Qualitative Analysis of the Amide Derivative of HLDF-6 Peptide and Its Metabolites with the Use of Tritium- and Deuterium-Labeled Derivatives].

    Science.gov (United States)

    Zolotarev, A; Dadayan, A K; Kost, N V; Voevodina, M E; Sokolov, O Y; Kozik, V S; Shram, S I; Azev, V N; Bocharov, E V; Bogachouk, A P; Lipkin, V M; Myasoedov, N F

    2015-01-01

    The goal of the study was to elaborate the pharmacokinetics methods of the amide derivative of peptide HLDF-6 (TGENHR-NH2) and its range of nootropic and neuroprotective activity is wide. The hexapeptide 41TGENHR46 is a fragment of the HDLF differentiation factor. It forms the basis for the development of preventive and therapeutic preparations for treating cerebrovascular and neurodegenerative conditions. Pharmacokinetic and molecular mechanisms of the action of the HLDF-6 peptide were studied using tritium- and deuterium-labeled derivatives of this peptide, produced with the use of the high-temperature solid-state catalytic isotope exchange reaction (HSCIE). This reaction was employed to produce the tritium-labeled peptide [3H]TGENHR-NH2 with a molar radioactivity of 230 Ci/mmol and the deuterium-labeled peptide [2H]TGENHR-NH2 with an average deuterium incorporation equal to 10.5 atoms. It was shown by the NMR spectroscopy that the isotope label distribution over the labeled peptide's molecule was uniform, which allowed qualitative analysis ofboth the peptide itself and its fragments in the organism's tissues to be conducted. The newly developed pharmacokinetics method makes it possible to avoid almost completely losses of the peptides under study due to biodegradation during the analysis of tissues. These labeled peptides were used in mice, rats and rabbits to study the pharmacokinetics of the peptide and to calculate the values of its principal pharmacokinetic parameters. Characteristics of its pharmacokinetic profile in the blood were obtained, the hypothesis of pharmacokinetics linearity tested, its metabolism analyzed and its bioavailability value, 34%, calculated. It has been shown that the studied TGENHR-NH2 peptide shows high resistance to hydrolysis in the blood plasma, with dipeptidyl aminopeptidases making the largest contribution to its hydrolysis.

  11. Synthesis and antifungal activities of glycosylated derivatives of the cyclic peptide fungicide caspofungin.

    Science.gov (United States)

    Guo, Junxiang; Hu, Honggang; Zhao, Qingjie; Wang, Ting; Zou, Yan; Yu, Shichong; Wu, Qiuye; Guo, Zhongwu

    2012-08-01

    Diseases caused by systemic fungal infections have become a significant clinical problem in recent decades. A series of glycosyl derivatives of the approved cyclic peptide antifungal drug caspofungin conjugated with β-D-glucopyranose, β-D-galactopyranose, β-D-xylopyranose, β-L-rhamnopyranose, β-maltose and β-lactose units were designed, synthesized, and evaluated as new potential antifungal drugs. The compounds were obtained by coupling the corresponding glycosyl amines to the free primary amino groups of caspofungin through a bifunctional glutaryl linker. In contrast to caspofungin, these glycosylated derivatives are soluble in water, but are not hygroscopic and moreover, are more stable than caspofungin under high humidity and temperature. CD studies showed that glycosylation has very little impact on the conformation of the cyclic peptide of caspofungin. In vitro antifungal tests against seven human pathogenic fungi revealed that the caspofungin-monosaccharide conjugates, but not the disaccharide conjugates, have increased antifungal activities against the majority of tested fungus species relative to caspofungin. The β-D-glucopyranosyl derivative 2 a showed the strongest and broadest antifungal activity, providing a lead for further studies.

  12. Reassessing APOBEC3G Inhibition by HIV-1 Vif-Derived Peptides.

    Science.gov (United States)

    Richards, Christopher M; Li, Ming; Perkins, Angela L; Rathore, Anurag; Harki, Daniel A; Harris, Reuben S

    2017-01-06

    The human APOBEC3G (A3G) enzyme restricts HIV-1 in the absence of the viral accessory protein viral infectivity factor (Vif) by deaminating viral cDNA cytosines to uracils. These uracil lesions base-pair with adenines during the completion of reverse transcription and result in A3G signature G-to-A mutations in the viral genome. Vif protects HIV-1 from A3G-mediated restriction by forming an E3-ubiquitin ligase complex to polyubiquitinate A3G and trigger its degradation. Prior studies indicated that Vif may also directly block the enzymatic activity of A3G and, provocatively, that Vif-derived peptides, Vif 25-39 and Vif 105-119, are similarly inhibitory. Here, we show that Vif 25-39 does not inhibit A3G enzymatic activity and that the inhibitory effect of Vif 105-119 and that of a shorter derivative Vif 107-115, although recapitulated, are non-specific. We also elaborate a simple method for assaying DNA cytosine deaminase activity that eliminates potential polymerase chain reaction-induced biases. Our results show that these Vif-derived peptides are unlikely to be useful as tools to study A3G function or as leads for the development of future therapeutics.

  13. Ghrelin-Derived Peptides: A Link between Appetite/Reward, GH Axis, and Psychiatric Disorders?

    Science.gov (United States)

    Labarthe, Alexandra; Fiquet, Oriane; Hassouna, Rim; Zizzari, Philippe; Lanfumey, Laurence; Ramoz, Nicolas; Grouselle, Dominique; Epelbaum, Jacques; Tolle, Virginie

    2014-01-01

    Psychiatric disorders are often associated with metabolic and hormonal alterations, including obesity, diabetes, metabolic syndrome as well as modifications in several biological rhythms including appetite, stress, sleep-wake cycles, and secretion of their corresponding endocrine regulators. Among the gastrointestinal hormones that regulate appetite and adapt the metabolism in response to nutritional, hedonic, and emotional dysfunctions, at the interface between endocrine, metabolic, and psychiatric disorders, ghrelin plays a unique role as the only one increasing appetite. The secretion of ghrelin is altered in several psychiatric disorders (anorexia, schizophrenia) as well as in metabolic disorders (obesity) and in animal models in response to emotional triggers (psychological stress …) but the relationship between these modifications and the physiopathology of psychiatric disorders remains unclear. Recently, a large literature showed that this key metabolic/endocrine regulator is involved in stress and reward-oriented behaviors and regulates anxiety and mood. In addition, preproghrelin is a complex prohormone but the roles of the other ghrelin-derived peptides, thought to act as functional ghrelin antagonists, are largely unknown. Altered ghrelin secretion and/or signaling in psychiatric diseases are thought to participate in altered appetite, hedonic response and reward. Whether this can contribute to the mechanism responsible for the development of the disease or can help to minimize some symptoms associated with these psychiatric disorders is discussed in the present review. We will thus describe (1) the biological actions of ghrelin and ghrelin-derived peptides on food and drugs reward, anxiety and depression, and the physiological consequences of ghrelin invalidation on these parameters, (2) how ghrelin and ghrelin-derived peptides are regulated in animal models of psychiatric diseases and in human psychiatric disorders in relation with the GH axis.

  14. Ghrelin-derived peptides: a link between appetite/reward, GH axis and psychiatric disorders ?

    Directory of Open Access Journals (Sweden)

    Alexandra eLabarthe

    2014-10-01

    Full Text Available Psychiatric disorders are often associated with metabolic and hormonal alterations, including obesity, diabetes, metabolic syndrome as well as modifications in several biological rhythms including appetite, stress, sleep-wake cycles and secretion of their corresponding endocrine regulators.Among the gastrointestinal hormones that regulate appetite and adapt the metabolism in response to nutritional, hedonic and emotional dysfunctions, at the interface between endocrine, metabolic and psychiatric disorders, ghrelin plays a unique role as the only one increasing appetite. The secretion of ghrelin is altered in several psychiatric disorders (anorexia, schizophrenia as well as in metabolic disorders (obesity and in animal models in response to emotional triggers (psychological stress, …. but the relationship between these modifications and the physiopathology of psychiatric disorders remains unclear. Recently, a large literature showed that this key metabolic/endocrine regulator is involved in stress and reward-oriented behaviors and regulates anxiety and mood. In addition, preproghrelin is a complex prohormone but the roles of the other ghrelin-derived peptides, thought to act as functional ghrelin antagonists, are largely unknown. Altered ghrelin secretion and/or signaling in psychiatric diseases are thought to participate in altered appetite, hedonic response and reward. Whether this can contribute to the mechanism responsible for the development of the disease or can help to minimize some symptoms associated with these psychiatric disorders is discussed in the present review. We will thus describe 1 the biological actions of ghrelin and ghrelin-derived peptides on food and drugs reward, anxiety and depression, and the physiological consequences of ghrelin invalidation on these parameters, 2 how ghrelin and ghrelin-derived peptides are regulated in animal models of psychiatric diseases and in human psychiatric disorders in relation with the GH

  15. Solid-phase synthesis, characterization, and cellular activities of collagen-model nanodiamond-peptide conjugates.

    Science.gov (United States)

    Knapinska, Anna M; Tokmina-Roszyk, Dorota; Amar, Sabrina; Tokmina-Roszyk, Michal; Mochalin, Vadym N; Gogotsi, Yury; Cosme, Patrick; Terentis, Andrew C; Fields, Gregg B

    2015-05-01

    Nanodiamonds (NDs) have received considerable attention as potential drug delivery vehicles. NDs are small (∼5 nm diameter), can be surface modified in a controllable fashion with a variety of functional groups, and have little observed toxicity in vitro and in vivo. However, most biomedical applications of NDs utilize surface adsorption of biomolecules, as opposed to covalent attachment. Covalent modification provides reliable and reproducible ND-biomolecule ratios, and alleviates concerns over biomolecule desorption prior to delivery. The present study has outlined methods for the efficient solid-phase conjugation of ND to peptides and characterization of ND-peptide conjugates. Utilizing collagen-derived peptides, the ND was found to support or even enhance the cell adhesion and viability activities of the conjugated sequence. Thus, NDs can be incorporated into peptides and proteins in a selective manner, where the presence of the ND could potentially enhance the in vivo activities of the biomolecule it is attached to.

  16. C-type natriuretic-derived peptides as biomarkers in human disease

    DEFF Research Database (Denmark)

    Lippert, Solvej Kølvraa; Goetze, Jens Peter

    2010-01-01

    The natriuretic peptide system comprises three structurally related peptides: atrial natriuretic peptide, B-type natriuretic peptide and C-type natriuretic peptide. In circulation, they play an important endocrine role in the regulation of cardiovascular homeostasis by maintaining blood pressure...... and extracellular fluid volume. Atrial natriuretic peptide and B-type natriuretic peptide have gained considerable diagnostic interest as biomarkers in cardiovascular disease. By contrast, C-type natriuretic peptide has not yet been ascribed a role in human diagnostics. This perspective aims at recapitulating...... the present biochemical and clinical issues concerning C-type natriuretic peptide measurement in plasma as a potential biomarker....

  17. Antibacterial activity and mechanism of a scorpion venom peptide derivative in vitro and in vivo.

    Directory of Open Access Journals (Sweden)

    Luyang Cao

    Full Text Available BmKn2 is an antimicrobial peptide (AMP characterized from the venom of scorpion Mesobuthus martensii Karsch by our group. In this study, Kn2-7 was derived from BmKn2 to improve the antibacterial activity and decrease hemolytic activity. Kn2-7 showed increased inhibitory activity against both gram-positive bacteria and gram-negative bacteria. Moreover, Kn2-7 exhibited higher antibacterial activity against clinical antibiotic-resistant strains such as methicillin-resistant Staphylococcus aureus (MRSA. In addition, the topical use of Kn2-7 effectively protected the skin of mice from infection in an S. aureus mouse skin infection model. Kn2-7 exerted its antibacterial activity via a bactericidal mechanism. Kn2-7 killed S. aureus and E. coli rapidly by binding to the lipoteichoic acid (LTA in the S. aureus cell wall and the lipopolysaccharides (LPS in the E. coli cell wall, respectively. Finally, the hemolytic activity of Kn2-7 was significantly decreased, compared to the wild-type peptide BmKn2. Taken together, the Kn2-7 peptide can be developed as a topical therapeutic agent for treating bacterial infections.

  18. Derivation of an amino acid similarity matrix for peptide:MHC binding and its application as a Bayesian prior

    Directory of Open Access Journals (Sweden)

    Sette Alessandro

    2009-11-01

    Full Text Available Abstract Background Experts in peptide:MHC binding studies are often able to estimate the impact of a single residue substitution based on a heuristic understanding of amino acid similarity in an experimental context. Our aim is to quantify this measure of similarity to improve peptide:MHC binding prediction methods. This should help compensate for holes and bias in the sequence space coverage of existing peptide binding datasets. Results Here, a novel amino acid similarity matrix (PMBEC is directly derived from the binding affinity data of combinatorial peptide mixtures. Like BLOSUM62, this matrix captures well-known physicochemical properties of amino acid residues. However, PMBEC differs markedly from existing matrices in cases where residue substitution involves a reversal of electrostatic charge. To demonstrate its usefulness, we have developed a new peptide:MHC class I binding prediction method, using the matrix as a Bayesian prior. We show that the new method can compensate for missing information on specific residues in the training data. We also carried out a large-scale benchmark, and its results indicate that prediction performance of the new method is comparable to that of the best neural network based approaches for peptide:MHC class I binding. Conclusion A novel amino acid similarity matrix has been derived for peptide:MHC binding interactions. One prominent feature of the matrix is that it disfavors substitution of residues with opposite charges. Given that the matrix was derived from experimentally determined peptide:MHC binding affinity measurements, this feature is likely shared by all peptide:protein interactions. In addition, we have demonstrated the usefulness of the matrix as a Bayesian prior in an improved scoring-matrix based peptide:MHC class I prediction method. A software implementation of the method is available at: http://www.mhc-pathway.net/smmpmbec.

  19. Regulation of embryonic cell adhesion by the cadherin cytoplasmic domain.

    Science.gov (United States)

    Kintner, C

    1992-04-17

    Differential adhesion between embryonic cells has been proposed to be mediated by a family of closely related glycoproteins called the cadherins. The cadherins mediate adhesion in part through an interaction between the cadherin cytoplasmic domain and intracellular proteins, called the catenins. To determine whether these interactions could regulate cadherin function in embryos, a form of N-cadherin was generated that lacks an extracellular domain. Expression of this mutant in Xenopus embryos causes a dramatic inhibition of cell adhesion. Analysis of the mutant phenotype shows that at least two regions of the N-cadherin cytoplasmic domain can inhibit adhesion and that the mutant cadherin can inhibit catenin binding to E-cadherin. These results suggest that cadherin-mediated adhesion can be regulated by cytoplasmic interactions and that this regulation may contribute to morphogenesis when emerging tissues coexpress several cadherin types.

  20. RNA-binding IMPs promote cell adhesion and invadopodia formation

    DEFF Research Database (Denmark)

    Vikesaa, Jonas; Hansen, Thomas V O; Jønson, Lars

    2006-01-01

    Oncofetal RNA-binding IMPs have been implicated in mRNA localization, nuclear export, turnover and translational control. To depict the cellular actions of IMPs, we performed a loss-of-function analysis, which showed that IMPs are necessary for proper cell adhesion, cytoplasmic spreading...... and invadopodia formation. Loss of IMPs was associated with a coordinate downregulation of mRNAs encoding extracellular matrix and adhesion proteins. The transcripts were present in IMP RNP granules, implying that IMPs were directly involved in the post-transcriptional control of the transcripts. In particular......, we show that a 5.0 kb CD44 mRNA contained multiple IMP-binding sites in its 3'UTR, and following IMP depletion this species became unstable. Direct knockdown of the CD44 transcript mimicked the effect of IMPs on invadopodia, and we infer that CD44 mRNA stabilization may be involved in IMP...

  1. Simulation of Cell Adhesion using a Particle Transport Model

    Science.gov (United States)

    Chesnutt, Jennifer

    2005-11-01

    An efficient computational method for simulation of cell adhesion through protein binding forces is discussed. In this method, the cells are represented by deformable elastic particles, and the protein binding is represented by a rate equation. The method is first developed for collision and adhesion of two similar cells impacting on each other from opposite directions. The computational method is then applied in a particle-transport model for a cloud of interacting and colliding cells, each of which are represented by particles of finite size. One application might include red blood cells adhering together to form rouleaux, which are chains of red blood cells that are found in different parts of the circulatory system. Other potential applications include adhesion of platelets to a blood vessel wall or mechanical heart valve, which is a precursor of thrombosis formation, or adhesion of cancer cells to organ walls in the lymphatic, circulatory, digestive or pulmonary systems.

  2. The MRL proteins: adapting cell adhesion, migration and growth.

    Science.gov (United States)

    Coló, Georgina P; Lafuente, Esther M; Teixidó, Joaquin

    2012-01-01

    MIG-10, RIAM and Lamellipodin (Lpd) are the founding members of the MRL family of multi-adaptor molecules. These proteins have common domain structures but display distinct functions in cell migration and adhesion, signaling, and in cell growth. The binding of RIAM with active Rap1 and with talin provides these MRL molecules with important regulatory roles on integrin-mediated cell adhesion and migration. Furthermore, RIAM and Lpd can regulate actin dynamics through their binding to actin regulatory Ena/VASP proteins. Recent data generated with the Drosophila MRL ortholog called Pico and with RIAM in melanoma cells indicate that these proteins can also regulate cell growth. As MRL proteins represent a relatively new family, many questions on their structure-function relationships remain unanswered, including regulation of their expression, post-translational modifications, new interactions, involvement in signaling and their knockout mice phenotype.

  3. Growth hormone increases vascular cell adhesion molecule 1 expression

    DEFF Research Database (Denmark)

    Hansen, Troels Krarup; Fisker, Sanne; Dall, Rolf

    2004-01-01

    We investigated the impact of GH administration on endothelial adhesion molecules, vascular cell adhesion molecule-1 (VCAM-1) and E-selectin, in vivo and in vitro. Soluble VCAM-1, E-selectin, and C-reactive protein concentrations were measured before and after treatment in 25 healthy subjects...... and 25 adult GH-deficient (GHD) patients randomized to GH treatment or placebo. Furthermore, we studied the direct effect of GH and IGF-I and serum from GH-treated subjects on basal and TNF alpha-stimulated expression of VCAM-1 and E-selectin on cultured human umbilical vein endothelial cells. Baseline...... levels of VCAM-1, but not E-selectin, were significantly lower in GHD patients than in healthy subjects (362 +/- 15 microg/liter vs. 516 +/- 21 microg/liter, P treatment, compared with placebo [net difference between groups 151.8 microg/liter (95...

  4. Osteoblastlike cell adhesion on titanium surfaces modified by plasma nitriding.

    Science.gov (United States)

    da Silva, Jose Sandro Pereira; Amico, Sandro Campos; Rodrigues, Almir Olegario Neves; Barboza, Carlos Augusto Galvao; Alves, Clodomiro; Croci, Alberto Tesconi

    2011-01-01

    The aim of this study was to evaluate the characteristics of various titanium surfaces modified by cold plasma nitriding in terms of adhesion and proliferation of rat osteoblastlike cells. Samples of grade 2 titanium were subjected to three different surface modification processes: polishing, nitriding by plasma direct current, and nitriding by cathodic cage discharge. To evaluate the effect of the surface treatment on the cellular response, the adhesion and proliferation of osteoblastlike cells (MC3T3) were quantified and the results were analyzed by Kruskal-Wallis and Friedman statistical tests. Cellular morphology was observed by scanning electron microscopy. There was more MC3T3 cell attachment on the rougher surfaces produced by cathodic cage discharge compared with polished samples (P Plasma nitriding improves titanium surface roughness and wettability, leading to osteoblastlike cell adhesion.

  5. Liposomal leakage induced by virus-derived peptides, viral proteins, and entire virions: rapid analysis by chip electrophoresis.

    Science.gov (United States)

    Weiss, Victor U; Bilek, Gerhard; Pickl-Herk, Angela; Subirats, Xavier; Niespodziana, Katarzyna; Valenta, Rudolf; Blaas, Dieter; Kenndler, Ernst

    2010-10-01

    Permeabilization of model lipid membranes by virus-derived peptides, viral proteins, and entire virions of human rhinovirus was assessed by quantifying the release of a fluorescent dye from liposomes via a novel chip electrophoretic assay. Liposomal leakage readily occurred upon incubation with the pH-sensitive synthetic fusogenic peptide GALA and, less efficiently, with a 24mer peptide (P1-N) derived from the N-terminus of the capsid protein VP1 of human rhinovirus 2 (HRV2) at acidic pH. Negative stain transmission electron microscopy showed that liposomes incubated with the rhinovirus-derived peptide remained largely intact. At similar concentrations, the GALA peptide caused gross morphological changes of the liposomes. On a molar basis, the leakage-inducing efficiency of the P1 peptide was by about 2 orders of magnitude inferior to that of recombinant VP1 (from HRV89) and entire HRV2. This underscores the role in membrane destabilization of VP1 domains remote from the N-terminus and the arrangement of the peptide in the context of the icosahedral virion. Our method is rapid, requires tiny amounts of sample, and allows for the parallel determination of released and retained liposomal cargo.

  6. Epithelial cell adhesion and gastrointestinal colonization of Lactobacillus in poultry.

    Science.gov (United States)

    Spivey, Megan A; Dunn-Horrocks, Sadie L; Duong, Tri

    2014-11-01

    Administration of probiotic Lactobacillus cultures is an important alternative to the use of antibiotic growth promoters and has been demonstrated to improve animal health, growth performance, and preharvest food safety in poultry production. Whereas gastrointestinal colonization is thought to be critical to their probiotic functionality, factors important to Lactobacillus colonization in chickens are not well understood. In this study we investigate epithelial cell adhesion in vitro and colonization of Lactobacillusin vivo in broiler chickens. Adhesion of Lactobacillus cultures to epithelial cells was evaluated using the chicken LMH cell line. Lactobacillus cultures were able adhere effectively to LMH cells relative to Bacillus subtilis and Salmonella Typhimurium. Epithelial cell adhesion was similar for Lactobacillus crispatus TDCC 75, L. cristpatus TDCC 76, and Lactobacillus gallinarum TDCC 77, and all 3 were more adherent than L. gallinarum TDCC 78. However, when colonization was evaluated in the ileum and cecum of broiler chicks, L. crispatus TDCC 75 and L. gallinarum TDCC 77 were more persistent than L. crispatus TDCC 76 and L. gallinarum TDCC 78. The reduction of growth in medium supplemented with oxgal was greater for L. gallinarum TDCC 78 than L. gallinarum TDCC 77, suggesting that whereas adhesion was similar for the 2 strains, the difference in colonization between L. gallinarum strains may be due in part to their bile sensitivity. This study demonstrates that whereas adhesion to epithelial cells may be important in predicting gastrointestinal colonization, other factors including bile tolerance may also contribute to the colonization of Lactobacillus in poultry. Additionally, the chicken LMH cell line is expected to provide a platform for investigating mechanisms of Lactobacillus adhesion to epithelial tissue and evaluating the probiotic potential Lactobacillus in poultry.

  7. Activin Receptor Signaling Regulates Prostatic Epithelial Cell Adhesion and Viability

    Directory of Open Access Journals (Sweden)

    Derek P. Simon

    2009-04-01

    Full Text Available Mutational changes coupled with endocrine, paracrine, and/or autocrine signals regulate cell division during carcinogenesis. The hormone signals remain undefined, although the absolute requirement in vitro for fetal serum indicates the necessity for a fetal serum factor(s in cell proliferation. Using prostatic cancer cell (PCC lines as a model of cancer cell proliferation, we have identified the fetal serum component activin A and its signaling through the activin receptor type II (ActRII, as necessary, although not sufficient, for PCC proliferation. Activin A induced Smad2 phosphorylation and PCC proliferation, but only in the presence of fetal bovine serum (FBS. Conversely, activin A antibodies and inhibin A suppressed FBS-induced PCC proliferation confirming activin A as one of multiple serum components required for PCC proliferation. Basic fibroblast growth factor was subsequently shown to synergize activin A-induced PCC proliferation. Inhibition of ActRII signaling using a blocking antibody or antisense-P decreased mature ActRII expression, Smad2 phosphorylation, and the apparent viability of PCCs and neuroblastoma cells grown in FBS. Suppression of ActRII signaling in PCC and neuroblastoma cells did not induce apoptosis as indicated by the ratio of active/inactive caspase 3 but did correlate with increased cell detachment and ADAM-15 expression, a disintegrin whose expression is strongly correlated with prostatic metastasis. These findings indicate that ActRII signaling is required for PCC and neuroblastoma cell viability, with ActRII mediating cell fate via the regulation of cell adhesion. That ActRII signaling governs both cell viability and cell adhesion has important implications for developing therapeutic strategies to regulate cancer growth and metastasis.

  8. Dermcidin-derived peptides show a different mode of action than the cathelicidin LL-37 against Staphylococcus aureus.

    Science.gov (United States)

    Senyürek, Ilknur; Paulmann, Maren; Sinnberg, Tobias; Kalbacher, Hubert; Deeg, Martin; Gutsmann, Thomas; Hermes, Marina; Kohler, Thomas; Götz, Fritz; Wolz, Christiane; Peschel, Andreas; Schittek, Birgit

    2009-06-01

    Dermcidin (DCD) is an antimicrobial peptide which is constitutively expressed in eccrine sweat glands. By postsecretory proteolytic processing in sweat, the DCD protein gives rise to anionic and cationic DCD peptides with a broad spectrum of antimicrobial activity. Many antimicrobial peptides induce membrane permeabilization as part of their killing mechanism, which is accompanied by a loss of the bacterial membrane potential. In this study we show that there is a time-dependent bactericidal activity of anionic and cationic DCD-derived peptides which is followed by bacterial membrane depolarization. However, DCD-derived peptides do not induce pore formation in the membranes of gram-negative and gram-positive bacteria. This is in contrast to the mode of action of the cathelicidin LL-37. Interestingly, LL-37 as well as DCD-derived peptides inhibit bacterial macromolecular synthesis, especially RNA and protein synthesis, without binding to microbial DNA or RNA. Binding studies with components of the cell envelope of gram-positive and gram-negative bacteria and with model membranes indicated that DCD-derived peptides bind to the bacterial envelope but show only a weak binding to lipopolysaccharide (LPS) from gram-negative bacteria or to peptidoglycan, lipoteichoic acid, and wall teichoic acid, isolated from Staphylococcus aureus. In contrast, LL-37 binds strongly in a dose-dependent fashion to these components. Altogether, these data indicate that the mode of action of DCD-derived peptides is different from that of the cathelicidin LL-37 and that components of the bacterial cell envelope play a role in the antimicrobial activity of DCD.

  9. The laminin-derived peptide C16 regulates GPNMB expression and function in breast cancer.

    Science.gov (United States)

    Smuczek, Basilio; Santos, Emerson de S; Siqueira, Adriane S; Pinheiro, Joao J V; Freitas, Vanessa M; Jaeger, Ruy G

    2017-09-15

    Breast cancer is an important public health problem, and its progression may be related to the extracellular matrix (ECM), which acts as a structural scaffold and instruction source for neoplastic cells. Laminins are ECM proteins regulating tumor biology. The laminin-derived peptide C16 regulates different properties of tumor cells. Here we analyzed C16-induced differential gene expression in MDA-MB-231 breast cancer cells. MCF-10A normal-like breast cells served as control. Among different cancer-related genes, C16 induced overexpression of GPNMB. This gene encodes a transmembrane protein GPNMB (glycoprotein non-metastatic B), involved with malignant phenotype of breast cancer cells. Immunoblot validated microarray results. To correlate gene and protein expression with cellular function, we investigated whether C16 would regulate invasion in breast cancer cells. siRNA experiments strongly suggested that C16 and GPNMB cooperate to regulate invasion of highly aggressive MDA-MB-231 cancer cells. We addressed regulatory mechanisms involved in C16-mediated increase of GPNMB protein levels in MDA-MB-231 cells, and observed that C16 stimulates β1 integrin and Src phosphorylation. Furthermore, Src inhibition decreases peptide-induced GPNMB expression levels. To contextualize in vivo our results in vitro, we addressed GPNMB immunostaining in breast cancer human tissue microarrays. Quantitative immunohistochemistry showed that GPNMB is significantly more expressed in breast cancer compared to normal tissue. We concluded that laminin-derived peptide C16 regulates gene and protein expression of GPNMB in breast cancer cells. C16 and GPNMB may cooperate to regulate invasion of highly aggressive MDA-MB-231 cells, probably through Src signaling. GPNMB presented increased expression in breast cancer in vivo compared to normal breast tissue. Copyright © 2017. Published by Elsevier Inc.

  10. Ndel1-derived peptides modulate bidirectional transport of injected beads in the squid giant axon

    Directory of Open Access Journals (Sweden)

    Michal Segal

    2012-01-01

    Bidirectional transport is a key issue in cellular biology. It requires coordination between microtubule-associated molecular motors that work in opposing directions. The major retrograde and anterograde motors involved in bidirectional transport are cytoplasmic dynein and conventional kinesin, respectively. It is clear that failures in molecular motor activity bear severe consequences, especially in the nervous system. Neuronal migration may be impaired during brain development, and impaired molecular motor activity in the adult is one of the hallmarks of neurodegenerative diseases leading to neuronal cell death. The mechanisms that regulate or coordinate kinesin and dynein activity to generate bidirectional transport of the same cargo are of utmost importance. We examined how Ndel1, a cytoplasmic dynein binding protein, may regulate non-vesicular bidirectional transport. Soluble Ndel1 protein, Ndel1-derived peptides or control proteins were mixed with fluorescent beads, injected into the squid giant axon, and the bead movements were recorded using time-lapse microscopy. Automated tracking allowed for extraction and unbiased analysis of a large data set. Beads moved in both directions with a clear bias to the anterograde direction. Velocities were distributed over a broad range and were typically slower than those associated with fast vesicle transport. Ironically, the main effect of Ndel1 and its derived peptides was an enhancement of anterograde motion. We propose that they may function primarily by inhibition of dynein-dependent resistance, which suggests that both dynein and kinesin motors may remain engaged with microtubules during bidirectional transport.

  11. Short- and long-term antihypertensive effect of egg protein-derived peptide QIGLF.

    Science.gov (United States)

    Yu, Zhipeng; Zhao, Wenzhu; Ding, Long; Wang, Yaqi; Chen, Feng; Liu, Jingbo

    2017-01-01

    The present study aimed to investigate the in vivo antihypertensive effect on spontaneously hypertensive rats (SHRs) induced by egg protein-derived peptide QIGLF, which has been previously characterized in vitro as a potent angiotensin-converting enzyme inhibitor. In vivo antihypertensive effect of QIGLF orally administered was evaluated by the tail-cuff method. The systolic blood pressure and the diastolic blood pressure of rats were measured 0, 5, 10, 15 and 20 h after administration every day. Subsequently, the effect of QIGLF on angiotensin-converting enzyme mRNA expression in the kidney of SHRs was evaluated by a polymerase chain reaction. Systolic blood pressure was found to be reduced markedly in the SHRs after a single oral administration. The results show that the effect of QIGLF (50 mg kg(-1) body weight) was similar to that of captopril (10 mg kg(-1) body weight) with respect to lowering systolic blood pressure in SHRs. Therefore, egg white protein-derived peptide QIGLF may be useful in the prevention or treatment of hypertension. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  12. Anti-atherogenic peptide Ep1.B derived from apolipoprotein E induces tolerogenic plasmacytoid dendritic cells.

    Science.gov (United States)

    Bellemore, S M; Nikoopour, E; Au, B C Y; Krougly, O; Lee-Chan, E; Haeryfar, S M; Singh, B

    2014-09-01

    Tolerogenic dendritic cells (DCs) play a critical role in the induction of regulatory T cells (Tregs ), which in turn suppress effector T cell responses. We have previously shown the induction of DCs from human and mouse monocytic cell lines, mouse splenocytes and human peripheral blood monocytes by a novel apolipoprotein E (ApoE)-derived self-peptide termed Ep1.B. We also showed that this C-terminal region 239-252 peptide of ApoE has strong anti-atherogenic activity and reduces neointimal hyperplasia after vascular surgery in rats and wild-type as well as ApoE-deficient mice. In this study, we explored the phenotype of DC subset induced by Ep1.B from monocytic cell lines and from the bone marrow-derived cells. We found Ep1.B treatment induced cells that showed characteristics of plasmacytoid dendritic cells (pDC). We explored in-vitro and in-vivo effects of Ep1.B-induced DCs on antigen-specific T cell responses. Upon in-vivo injection of these cells with antigen, the subsequent ex-vivo antigen-specific proliferation of lymph node cells and splenocytes from recipient mice was greatly reduced. Our results suggest that Ep1.B-induced pDCs promote the generation of Treg cells, and these cells contribute to the induction of peripheral tolerance in adaptive immunity and potentially contribute its anti-atherogenic activity.

  13. Free tyrosine and tyrosine-rich peptide-dependent superoxide generation catalyzed by a copper-binding, threonine-rich neurotoxic peptide derived from prion protein

    Directory of Open Access Journals (Sweden)

    Ken Yokawa, Tomoko Kagenishi, Kaishi Goto, Tomonori Kawano

    2009-01-01

    Full Text Available Previously, generation of superoxide anion (O2•- catalyzed by Cu-binding peptides derived from human prion protein (model sequence for helical Cu-binding motif VNITKQHTVTTTT was most active in the presence of catecholamines and related aromatic monoamines such as phenylethylamine and tyramine, has been reported [Kawano, T., Int J Biol Sci 2007; 3: 57-63]. The peptide sequence (corresponding to helix 2 tested here is known as threonine-rich neurotoxic peptide. In the present article, the redox behaviors of aromatic monoamines, 20 amino acids and prion-derived tyrosine-rich peptide sequences were compared as putative targets of the oxidative reactions mediated with the threonine-rich prion-peptide. For detection of O2•-, an O2•--specific chemiluminescence probe, Cypridina luciferin analog was used. We found that an aromatic amino acid, tyrosine (structurally similar to tyramine behaves as one of the best substrates for the O2•- generating reaction (conversion from hydrogen peroxide catalyzed by Cu-bound prion helical peptide. Data suggested that phenolic moiety is required to be an active substrate while the presence of neither carboxyl group nor amino group was necessarily required. In addition to the action of free tyrosine, effect of two tyrosine-rich peptide sequences YYR and DYEDRYYRENMHR found in human prion corresponding to the tyrosine-rich region was tested as putative substrates for the threonine-rich neurotoxic peptide. YYR motif (found twice in the Y-rich region showed 2- to 3-fold higher activity compared to free tyrosine. Comparison of Y-rich sequence consisted of 13 amino acids and its Y-to-F substitution mutant sequence revealed that the tyrosine-residues on Y-rich peptide derived from prion may contribute to the higher production of O2•-. These data suggest that the tyrosine residues on prion molecules could be additional targets of the prion-mediated reactions through intra- or inter-molecular interactions. Lastly

  14. Free tyrosine and tyrosine-rich peptide-dependent superoxide generation catalyzed by a copper-binding, threonine-rich neurotoxic peptide derived from prion protein.

    Science.gov (United States)

    Yokawa, Ken; Kagenishi, Tomoko; Goto, Kaishi; Kawano, Tomonori

    2009-01-01

    Previously, generation of superoxide anion (O(2)(*-)) catalyzed by Cu-binding peptides derived from human prion protein (model sequence for helical Cu-binding motif VNITKQHTVTTTT was most active) in the presence of catecholamines and related aromatic monoamines such as phenylethylamine and tyramine, has been reported [Kawano, T., Int J Biol Sci 2007; 3: 57-63]. The peptide sequence (corresponding to helix 2) tested here is known as threonine-rich neurotoxic peptide. In the present article, the redox behaviors of aromatic monoamines, 20 amino acids and prion-derived tyrosine-rich peptide sequences were compared as putative targets of the oxidative reactions mediated with the threonine-rich prion-peptide. For detection of O(2)(*-), an O(2)(*-)-specific chemiluminescence probe, Cypridina luciferin analog was used. We found that an aromatic amino acid, tyrosine (structurally similar to tyramine) behaves as one of the best substrates for the O(2)(*-) generating reaction (conversion from hydrogen peroxide) catalyzed by Cu-bound prion helical peptide. Data suggested that phenolic moiety is required to be an active substrate while the presence of neither carboxyl group nor amino group was necessarily required. In addition to the action of free tyrosine, effect of two tyrosine-rich peptide sequences YYR and DYEDRYYRENMHR found in human prion corresponding to the tyrosine-rich region was tested as putative substrates for the threonine-rich neurotoxic peptide. YYR motif (found twice in the Y-rich region) showed 2- to 3-fold higher activity compared to free tyrosine. Comparison of Y-rich sequence consisted of 13 amino acids and its Y-to-F substitution mutant sequence revealed that the tyrosine-residues on Y-rich peptide derived from prion may contribute to the higher production of O(2)(*-). These data suggest that the tyrosine residues on prion molecules could be additional targets of the prion-mediated reactions through intra- or inter-molecular interactions. Lastly, possible

  15. Peptide based DNA nanocarriers incorporating a cell-penetrating peptide derived from neurturin protein and poly-L-lysine dendrons.

    Science.gov (United States)

    Rosli, Nurlina; Christie, Michelle P; Moyle, Peter M; Toth, Istvan

    2015-05-15

    Multicomponent gene delivery systems incorporating cell-penetrating peptides (CPP) from the human neurturin protein (NRTN-30, NRTN(132-161); NRTN-17, NRTN(145-161)) and a poly-l-lysine (PLL) dendron, were synthesized and characterized for plasmid DNA (pDNA) delivery. Acetylated NRTN peptides (Ac-CPP) and peptides conjugated to a PLL dendron (DEN-CPP) efficiently condensed and stabilized pDNA. Complexes between pDNA and DEN-CPP formed smaller and more stable nanoparticles. Flow cytometry experiments showed that pDNA-DEN-CPPs were taken up more efficiently into HeLa cells. There was also no significant difference between NRTN-30 and NRTN-17 for pDNA uptake, indicating that the truncated peptide alone is sufficient as a CPP for pDNA delivery.

  16. Cateslytin, a chromogranin A derived peptide is active against Staphylococcus aureus and resistant to degradation by its proteases.

    Directory of Open Access Journals (Sweden)

    Rizwan Aslam

    Full Text Available Innate immunity involving antimicrobial peptides represents an integrated and highly effective system of molecular and cellular mechanisms that protects host against infections. One of the most frequent hospital-acquired pathogens, Staphylococcus aureus, capable of producing proteolytic enzymes, which can degrade the host defence agents and tissue components. Numerous antimicrobial peptides derived from chromogranins, are secreted by nervous, endocrine and immune cells during stress conditions. These kill microorganisms by their lytic effect at micromolar range, using a pore-forming mechanism against Gram-positive bacteria, filamentous fungi and yeasts. In this study, we tested antimicrobial activity of chromogranin A-derived peptides (catestatin and cateslytin against S. aureus and analysed S. aureus-mediated proteolysis of these peptides using HPLC, sequencing and MALDI-TOF mass spectrometry. Interestingly, this study is the first to demonstrate that cateslytin, the active domain of catestatin, is active against S. aureus and is interestingly resistant to degradation by S. aureus proteases.

  17. Antimicrobial Activity of Peptides Derived from Olive Flounder Lipopolysaccharide Binding Protein/Bactericidal Permeability-Increasing Protein (LBP/BPI

    Directory of Open Access Journals (Sweden)

    Bo-Hye Nam

    2014-10-01

    Full Text Available We describe the antimicrobial function of peptides derived from the C-terminus of the olive flounder LBP BPI precursor protein. The investigated peptides, namely, ofLBP1N, ofLBP2A, ofLBP4N, ofLBP5A, and ofLBP6A, formed α-helical structures, showing significant antimicrobial activity against several Gram-negative bacteria, Gram-positive bacteria, and the yeast Candida albicans, but very limited hemolytic activities. The biological activities of these five analogs were evaluated against biomembranes or artificial membranes for the development of candidate therapeutic agents. Gel retardation studies revealed that peptides bound to DNA and inhibited migration on an agarose gel. In addition, we demonstrated that ofLBP6A inhibited polymerase chain reaction. These results suggested that the ofLBP-derived peptide bactericidal mechanism may be related to the interaction with intracellular components such as DNA or polymerase.

  18. Antimicrobial activity of peptides derived from olive flounder lipopolysaccharide binding protein/bactericidal permeability-increasing protein (LBP/BPI).

    Science.gov (United States)

    Nam, Bo-Hye; Moon, Ji-Young; Park, Eun-Hee; Kim, Young-Ok; Kim, Dong-Gyun; Kong, Hee Jeong; Kim, Woo-Jin; Jee, Young Ju; An, Cheul Min; Park, Nam Gyu; Seo, Jung-Kil

    2014-10-17

    We describe the antimicrobial function of peptides derived from the C-terminus of the olive flounder LBP BPI precursor protein. The investigated peptides, namely, ofLBP1N, ofLBP2A, ofLBP4N, ofLBP5A, and ofLBP6A, formed α-helical structures, showing significant antimicrobial activity against several Gram-negative bacteria, Gram-positive bacteria, and the yeast Candida albicans, but very limited hemolytic activities. The biological activities of these five analogs were evaluated against biomembranes or artificial membranes for the development of candidate therapeutic agents. Gel retardation studies revealed that peptides bound to DNA and inhibited migration on an agarose gel. In addition, we demonstrated that ofLBP6A inhibited polymerase chain reaction. These results suggested that the ofLBP-derived peptide bactericidal mechanism may be related to the interaction with intracellular components such as DNA or polymerase.

  19. O-glycosylated versus non-glycosylated MUC1-derived peptides as potential targets for cytotoxic immunotherapy of carcinoma

    Science.gov (United States)

    Stepensky, D; Tzehoval, E; Vadai, E; Eisenbach, L

    2006-01-01

    Due to the fact that many cellular proteins are extensively glycosylated, processing and presentation mechanisms are expected to produce a pool of major histocompatibility complex (MHC) class I-bound protein-derived peptides, part of which retain sugar moieties. The immunogenic properties of the presented glycosylated peptides in comparison to their non-glycosylated counterparts have not been determined clearly. We assessed the cellular immunogenicity of MUC1 (mucin)-derived peptides O-glycosylated with a Tn epitope (GalNAc) using HLA-A*0201 single chain (HHD)-transfected cell lines and transgenic mice. For part of the compounds Tn moiety did not interfere with the HLA-A*0201 binding. Moreover, part of the glycopeptides elicited effective cytotoxic responses, indicating recognition of the glycopeptide-HLA-A*0201 complex by the T cell receptor (TCR) and subsequent cytotoxic T lymphocyte (CTL) activation. The CTLs exhibited a substantial degree of cross-reactivity against target cells loaded with glycosylated and non-glycosylated forms of the same peptide. The studied (glyco)peptides showed cellular immunogenicity in both MUC1-HHD and HHD mice and induced effective lysis of (glyco)peptide-loaded target cells in CTL assays. However, the elicited CTLs did not induce selective lysis of human MUC1-expressing murine cell lines. Moreover, immunization with (glyco)peptide-loaded dendritic cells (DCs) did not induce significant immunotherapeutic effects. We conclude that Tn glycosylated MUC1-derived peptides can be presented by MHC class I molecules, and may be recognized by specific TCR molecules resulting in cytotoxic immune responses. However, the studied glycopeptides did not offer significant benefit as targets for cytotoxic immune response due apparently to (a) cross-reactivity of the elicited CTLs against the glycosylated and non-glycosylated forms of the same peptide and (b) low abundance of glycopeptides on tumour target cells. PMID:16367945

  20. A PEDF-Derived Peptide Inhibits Retinal Neovascularization and Blocks Mobilization of Bone Marrow-Derived Endothelial Progenitor Cells

    Directory of Open Access Journals (Sweden)

    Richard Longeras

    2012-01-01

    Full Text Available Proliferative diabetic retinopathy is characterized by pathological retinal neovascularization, mediated by both angiogenesis (involving mature endothelial cells and vasculogenesis (involving bone marrow-derived circulating endothelial progenitor cells (EPCs. Pigment epithelium-derived factor (PEDF contains an N-terminal 34-amino acid peptide (PEDF-34 that has antiangiogenic properties. Herein, we present a novel finding that PEDF-34 also possesses antivasculogenic activity. In the oxygen-induced retinopathy (OIR model using transgenic mice that have Tie2 promoter-driven GFP expression, we quantified Tie2GFP+ cells in bone marrow and peripheral blood by fluorescence-activated cell sorting (FACS. OIR significantly increased the number of circulating Tie2-GFP+ at P16, correlating with the peak progression of neovascularization. Daily intraperitoneal injections of PEDF-34 into OIR mice decreased the number of Tie2-GFP+ cells in the circulation at P16 by 65% but did not affect the number of Tie2-GFP+ cells in the bone marrow. These studies suggest that PEDF-34 attenuates EPC mobilization from the bone marrow into the blood circulation during retinal neovascularization.

  1. Mussel-Inspired Polymer Carpets: Direct Photografting of Polymer Brushes on Polydopamine Nanosheets for Controlled Cell Adhesion.

    Science.gov (United States)

    Hafner, Daniel; Ziegler, Lisa; Ichwan, Muhammad; Zhang, Tao; Schneider, Maximilian; Schiffmann, Michael; Thomas, Claudia; Hinrichs, Karsten; Jordan, Rainer; Amin, Ihsan

    2016-02-17

    2D mussel-inspired polydopamine (PDA) nanosheets are prepared and exploited as a functional surface for grafting various polymer brushes. The PDA nanosheet and its polymer-brush derivatives show lateral integrity and are robust; therefore, they can be detached from their substrates. Cell-adhesion tests show that the PDA nanosheet promotes cell growth and attachment, while a PDA-based poly(3-sulfopropyl methacrylate) carpet exhibits nonfouling behavior. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Antibacterial Activity of Synthetic Peptides Derived from Lactoferricin against Escherichia coli ATCC 25922 and Enterococcus faecalis ATCC 29212

    Directory of Open Access Journals (Sweden)

    María A. León-Calvijo

    2015-01-01

    Full Text Available Peptides derived from human and bovine lactoferricin were designed, synthesized, purified, and characterized using RP-HPLC and MALDI-TOF-MS. Specific changes in the sequences were designed as (i the incorporation of unnatural amino acids in the sequence, the (ii reduction or (iii elongation of the peptide chain length, and (iv synthesis of molecules with different number of branches containing the same sequence. For each peptide, the antibacterial activity against Escherichia coli ATCC 25922 and Enterococcus faecalis ATCC 29212 was evaluated. Our results showed that Peptides I.2 (RWQWRWQWR and I.4 ((RRWQWR4K2Ahx2C2 exhibit bigger or similar activity against E. coli (MIC 4–33 μM and E. faecalis (MIC 10–33 μM when they were compared with lactoferricin protein (LF and some of its derivate peptides as II.1 (FKCRRWQWRMKKLGA and IV.1 (FKCRRWQWRMKKLGAPSITCVRRAE. It should be pointed out that Peptides I.2 and I.4, containing the RWQWR motif, are short and easy to synthesize; our results demonstrate that it is possible to design and obtain synthetic peptides that exhibit enhanced antibacterial activity using a methodology that is fast and low-cost and that allows obtaining products with a high degree of purity and high yield.

  3. Angiotensin I-converting enzyme inhibitory peptide derived from glycinin, the 11S globulin of soybean (Glycine max).

    Science.gov (United States)

    Mallikarjun Gouda, K G; Gowda, Lalitha R; Rao, A G Appu; Prakash, V

    2006-06-28

    Angiotensin I-converting enzyme (ACE), a dipeptidyl carboxypeptidase, catalyzes the conversion of Angiotensin I to the potent vasoconstrictor Angiotensin II and plays an important physiological role in regulating blood pressure. Inhibitors of angiotensin 1-converting enzyme derived from food proteins are utilized for pharmaceuticals and physiologically functional foods. ACE inhibitory properties of different enzymatic hydrolysates of glycinin, the major storage protein of soybean, have been demonstrated. The IC50 value for the different enzyme digests ranges from 4.5 to 35 microg of N2. The Protease P hydrolysate contained the most potent suite of ACE inhibitory peptides. The ACE inhibitory activity of the Protease P hydrolysate after fractionation by RP-HPLC and ion-pair chromatography was ascribed to a single peptide. The peptide was homogeneous as evidenced by MALDI-TOF and identified to be a pentapeptide. The sequence was Val-Leu-Ile-Val-Pro. This peptide was synthesized using solid-phase FMOC chemistry. The IC50 for ACE inhibition was 1.69 +/- 0.17 microM. The synthetic peptide was a potent competitive inhibitor of ACE with a Ki of 4.5 +/- 0.25 x 10(-6) M. This peptide was resistant to digestion by proteases of the gastrointestinal tract. The antihypertensive property of this peptide derived from glycinin might find importance in the development of therapeutic functional foods.

  4. Processing of pro-opiomelanocortin-derived amidated joining peptide and glycine-extended precursor in monkey pituitary

    DEFF Research Database (Denmark)

    Fenger, M

    1991-01-01

    The molecular forms of proopiomelanocortin (POMC) derived amidated and C-terminal glycine-extended joining peptide from monkey (Macaca mulatta) pituitary were determined. The predominant forms of joining peptide found were the low molecular peptides POMC(76-105) and POMC(76-106), respectively...... sequence of monkey and human POMC extremely conserved, but also the processing patterns are similar. The monkey therefore serves as a suitable model for studying regulation of the processing of POMC and the hypothalamus-pituitary-adrenal axis in man....

  5. Cell adhesive and antifouling polyvinyl chloride surfaces via wet chemical modification.

    Science.gov (United States)

    Gabriel, Matthias; Strand, Dennis; Vahl, Christian-Friedrich

    2012-09-01

    Polyvinyl chloride (PVC) is one of the most frequently used polymers for the manufacturing of medical devices. Limitations for its usage are based upon unfavorable surface properties of the polymer including its hydrophobicity and lack of functionalities in order to increase its versatility. To address this issue, wet chemical modification of PVC was performed through surface amination using the bifunctional compound ethylene diamine. The reaction was conducted in order to achieve maximum surface amination while leaving the bulk material unaffected. The initial activation step was characterized by means of various methods including contact angle measurements, colorimetric amine quantification, infrared spectroscopy, and gel permeation chromatography. Depth profiles were obtained by a confocal microscopic method using fluorescence labeling. Exclusive surface modification was thus confirmed. To demonstrate biological applications of the presented technique, two examples were chosen: The covalent immobilization of the cell adhesive Asp-Gly-Asp-Ser-peptide (RGD) onto PVC samples yielded a surface that strongly supported cellular adhesion and proliferation of fibroblasts. In contrast, the decoration of PVC with the hydrophilic polymer polyethylene glycol prevented cellular adhesion to a large extent. The impact of these modifications was demonstrated by cell culture experiments.

  6. A reagent-based dynamic trigger for cell adhesion, shape change, or cocultures.

    Science.gov (United States)

    van Dongen, Stijn F M; Maiuri, Paolo; Piel, Matthieu

    2014-01-01

    The described protocol is a simple and easily implemented method for making dynamic micropatterns for cell culture. It is based on the use of a surface coating material (azido-PLL-g-PEG (APP)) that initially repels cells, but which can be made strongly adherent by addition of a small functional peptide (BCN-RGD) to the cell culture medium. The method can be applied to trigger the adhesion, migration, or shape change of single cells or of populations of cells, and it can be used to create patterned cocultures. The entire process can be subdivided into three main parts. The first part describes the creation of patterned APP substrates. The second part describes cell seeding and "click" triggering of cell adhesion; the final part describes variations that allow the overlay of multiple patterns or the creation of patterned cocultures. The APP coating of substrates and the triggering of adhesion only involves treating the surface with aqueous stock solutions, allowing any biology lab to adopt this technique.

  7. C-type natriuretic-derived peptides as biomarkers in human disease

    DEFF Research Database (Denmark)

    Lippert, Solvej Kølvraa; Goetze, Jens Peter

    2010-01-01

    and extracellular fluid volume. Atrial natriuretic peptide and B-type natriuretic peptide have gained considerable diagnostic interest as biomarkers in cardiovascular disease. By contrast, C-type natriuretic peptide has not yet been ascribed a role in human diagnostics. This perspective aims at recapitulating...... the present biochemical and clinical issues concerning C-type natriuretic peptide measurement in plasma as a potential biomarker....

  8. Heterogeneity of glucagonomas due to differential processing of proglucagon-derived peptides

    Science.gov (United States)

    Challis, Benjamin G; Albrechtsen, Nicolai J Wewer; Bansiya, Vishakha; Burling, Keith; Barker, Peter; Hartmann, Bolette; Gribble, Fiona; O'Rahilly, Stephen

    2015-01-01

    Summary Pancreatic neuroendocrine tumours (pNETs) secreting proglucagon are associated with phenotypic heterogeneity. Here, we describe two patients with pNETs and varied clinical phenotypes due to differential processing and secretion of proglucagon-derived peptides (PGDPs). Case 1, a 57-year-old woman presented with necrolytic migratory erythema, anorexia, constipation and hyperinsulinaemic hypoglycaemia. She was found to have a grade 1 pNET, small bowel mucosal thickening and hyperglucagonaemia. Somatostatin analogue (SSA) therapy improved appetite, abolished hypoglycaemia and improved the rash. Case 2, a 48-year-old male presented with diabetes mellitus, diarrhoea, weight loss, nausea, vomiting and perineal rash due to a grade 1 metastatic pNET and hyperglucagonaemia. In both cases, plasma levels of all measured PGDPs were elevated and attenuated following SSA therapy. In case 1, there was increased production of intact glucagon-like peptide 1 (GLP-1) and GLP-2, similar to that of the enteroendocrine L cell. In case 2, pancreatic glucagon was elevated due to a pancreatic α-cell-like proglucagon processing profile. In summary, we describe two patients with pNETs and heterogeneous clinical phenotypes due to differential processing and secretion of PGDPs. This is the first description of a patient with symptomatic hyperinsulinaemic hypoglycaemia and marked gastrointestinal dysfunction due to, in part, a proglucagon-expressing pNET. Learning points PGDPs exhibit a diverse range of biological activities including critical roles in glucose and amino acid metabolism, energy homeostasis and gastrointestinal physiology.The clinical manifestations of proglucagon-expressing tumours may exhibit marked phenotypic variation due to the biochemical heterogeneity of their secreted peptide repertoire.Specific and precise biochemical assessment of individuals with proglucagon-expressing tumours may provide opportunities for improved diagnosis and clinical management. PMID

  9. The Antifungal Activity of Lactoferrin and Its Derived Peptides: Mechanisms of Action and Synergy with Drugs against Fungal Pathogens

    Science.gov (United States)

    Fernandes, Kenya E.; Carter, Dee A.

    2017-01-01

    Lactoferrin is a multifunctional iron-binding glycoprotein belonging to the transferrin family. It is found abundantly in milk and is present as a major protein in human exocrine secretions where it plays a role in the innate immune response. Various antifungal functions of lactoferrin have been reported including a wide spectrum of activity across yeasts and molds and synergy with other antifungal drugs in combination therapy, and various modes of action have been proposed. Bioactive peptides derived from lactoferrin can also exhibit strong antifungal activity, with some surpassing the potency of the whole protein. This paper reviews current knowledge of the spectrum of activity, proposed mechanisms of action, and capacity for synergy of lactoferrin and its peptides, including the three most studied derivatives: lactoferricin, lactoferrampin, and Lf(1–11), as well as some lactoferrin-derived variants and modified peptides. PMID:28149293

  10. Promiscuous binding of invariant chain-derived CLIP peptide to distinct HLA-I molecules revealed in leukemic cells.

    Science.gov (United States)

    van Luijn, Marvin M; van de Loosdrecht, Arjan A; Lampen, Margit H; van Veelen, Peter A; Zevenbergen, Adri; Kester, Michel G D; de Ru, Arnoud H; Ossenkoppele, Gert J; van Hall, Thorbald; van Ham, S Marieke

    2012-01-01

    Antigen presentation by HLA class I (HLA-I) and HLA class II (HLA-II) complexes is achieved by proteins that are specific for their respective processing pathway. The invariant chain (Ii)-derived peptide CLIP is required for HLA-II-mediated antigen presentation by stabilizing HLA-II molecules before antigen loading through transient and promiscuous binding to different HLA-II peptide grooves. Here, we demonstrate alternative binding of CLIP to surface HLA-I molecules on leukemic cells. In HLA-II-negative AML cells, we found plasma membrane display of the CLIP peptide. Silencing Ii in AML cells resulted in reduced HLA-I cell surface display, which indicated a direct role of CLIP in the HLA-I antigen presentation pathway. In HLA-I-specific peptide eluates from B-LCLs, five Ii-derived peptides were identified, of which two were from the CLIP region. In vitro peptide binding assays strikingly revealed that the eluted CLIP peptide RMATPLLMQALPM efficiently bound to four distinct HLA-I supertypes (-A2, -B7, -A3, -B40). Furthermore, shorter length variants of this CLIP peptide also bound to these four supertypes, although in silico algorithms only predicted binding to HLA-A2 or -B7. Immunization of HLA-A2 transgenic mice with these peptides did not induce CTL responses. Together these data show a remarkable promiscuity of CLIP for binding to a wide variety of HLA-I molecules. The found participation of CLIP in the HLA-I antigen presentation pathway could reflect an aberrant mechanism in leukemic cells, but might also lead to elucidation of novel processing pathways or immune escape mechanisms.

  11. Promiscuous binding of invariant chain-derived CLIP peptide to distinct HLA-I molecules revealed in leukemic cells.

    Directory of Open Access Journals (Sweden)

    Marvin M van Luijn

    Full Text Available Antigen presentation by HLA class I (HLA-I and HLA class II (HLA-II complexes is achieved by proteins that are specific for their respective processing pathway. The invariant chain (Ii-derived peptide CLIP is required for HLA-II-mediated antigen presentation by stabilizing HLA-II molecules before antigen loading through transient and promiscuous binding to different HLA-II peptide grooves. Here, we demonstrate alternative binding of CLIP to surface HLA-I molecules on leukemic cells. In HLA-II-negative AML cells, we found plasma membrane display of the CLIP peptide. Silencing Ii in AML cells resulted in reduced HLA-I cell surface display, which indicated a direct role of CLIP in the HLA-I antigen presentation pathway. In HLA-I-specific peptide eluates from B-LCLs, five Ii-derived peptides were identified, of which two were from the CLIP region. In vitro peptide binding assays strikingly revealed that the eluted CLIP peptide RMATPLLMQALPM efficiently bound to four distinct HLA-I supertypes (-A2, -B7, -A3, -B40. Furthermore, shorter length variants of this CLIP peptide also bound to these four supertypes, although in silico algorithms only predicted binding to HLA-A2 or -B7. Immunization of HLA-A2 transgenic mice with these peptides did not induce CTL responses. Together these data show a remarkable promiscuity of CLIP for binding to a wide variety of HLA-I molecules. The found participation of CLIP in the HLA-I antigen presentation pathway could reflect an aberrant mechanism in leukemic cells, but might also lead to elucidation of novel processing pathways or immune escape mechanisms.

  12. A polyalanine peptide derived from polar fish with anti-infectious activities

    Science.gov (United States)

    Cardoso, Marlon H.; Ribeiro, Suzana M.; Nolasco, Diego O.; de La Fuente-Núñez, César; Felício, Mário R.; Gonçalves, Sónia; Matos, Carolina O.; Liao, Luciano M.; Santos, Nuno C.; Hancock, Robert E. W.; Franco, Octávio L.; Migliolo, Ludovico

    2016-02-01

    Due to the growing concern about antibiotic-resistant microbial infections, increasing support has been given to new drug discovery programs. A promising alternative to counter bacterial infections includes the antimicrobial peptides (AMPs), which have emerged as model molecules for rational design strategies. Here we focused on the study of Pa-MAP 1.9, a rationally designed AMP derived from the polar fish Pleuronectes americanus. Pa-MAP 1.9 was active against Gram-negative planktonic bacteria and biofilms, without being cytotoxic to mammalian cells. By using AFM, leakage assays, CD spectroscopy and in silico tools, we found that Pa-MAP 1.9 may be acting both on intracellular targets and on the bacterial surface, also being more efficient at interacting with anionic LUVs mimicking Gram-negative bacterial surface, where this peptide adopts α-helical conformations, than cholesterol-enriched LUVs mimicking mammalian cells. Thus, as bacteria present varied physiological features that favor antibiotic-resistance, Pa-MAP 1.9 could be a promising candidate in the development of tools against infections caused by pathogenic bacteria.

  13. Peptide-based targeting of the platelet-derived growth factor receptor beta.

    Science.gov (United States)

    Askoxylakis, Vasileios; Marr, Annabell; Altmann, Annette; Markert, Annette; Mier, Walter; Debus, Jürgen; Huber, Peter E; Haberkorn, Uwe

    2013-04-01

    The aim of this work is to identify new ligands targeting the platelet-derived growth factor receptor beta (PDGFRβ). Biopanning was carried out with a 12-amino-acid phage display library against the recombinant extracellular domain of PDGFRβ. The identified peptide PDGFR-P1 was chemically synthesized and labeled with (125)I or (131)I. In vitro studies were performed on the PDGFRβ-expressing cell lines BxPC3 and MCF7 and on PDGFRβ-transfected HEK cells in comparison to negative control wtHEK293 and CaIX-transfected HEK cells. Biodistribution experiments were performed in Balb/c nude mice, carrying subcutaneously BxPC3 tumors. In vitro studies demonstrated a higher binding to BxPC3, MCF7, and PDGFRβ-tr-HEK cells in comparison to negative control cell lines. Binding was inhibited up to 90% by the unlabeled PDGFR-P1 peptide. Organ distribution studies revealed a higher accumulation in BxPC3 tumors than in most organs. PDGFR-P1 is a promising candidate for targeting human PDGFRβ.

  14. Distinct behaviour of the homeodomain derived cell penetrating peptide penetratin in interaction with different phospholipids.

    Directory of Open Access Journals (Sweden)

    Ofelia Maniti

    Full Text Available BACKGROUND: Penetratin is a protein transduction domain derived from the homeoprotein Antennapedia. Thereby it is currently used as a cell penetrating peptide to introduce diverse molecules into eukaryotic cells, and it could also be involved in the cellular export of transcription factors. Moreover, it has been shown that it is able to act as an antimicrobial agent. The mechanisms involved in all these processes are quite controversial. METHODOLOGY/PRINCIPAL FINDINGS: In this article, we report spectroscopic, calorimetric and biochemical data on the penetratin interaction with three different phospholipids: phosphatidylcholine (PC and phosphatidylethanolamine (PE to mimic respectively the outer and the inner leaflets of the eukaryotic plasma membrane and phosphatidylglycerol (PG to mimic the bacterial membrane. We demonstrate that with PC, penetratin is able to form vesicle aggregates with no major change in membrane fluidity and presents no well defined secondary structure organization. With PE, penetratin aggregates vesicles, increases membrane rigidity and acquires an α-helical structure. With PG membranes, penetratin does not aggregate vesicles but decreases membrane fluidity and acquires a structure with both α-helical and β-sheet contributions. CONCLUSIONS/SIGNIFICANCE: These data from membrane models suggest that the different penetratin actions in eukaryotic cells (membrane translocation during export and import and on prokaryotes may result from different peptide and lipid structural arrangements. The data suggest that, for eukaryotic cell penetration, penetratin does not acquire classical secondary structure but requires a different conformation compared to that in solution.

  15. The in Vitro Immune-Modulating Properties of a Sweat Gland-Derived Antimicrobial Peptide Dermcidin.

    Science.gov (United States)

    Wang, Echo; Qiang, Xiaoling; Li, Jianhua; Zhu, Shu; Wang, Ping

    2016-01-01

    The epidermal barriers of the skin serve as the first layer of defense by limiting the access of many pathogens to the blood circulation. In addition, human skin also contains sweat glands that can secrete a wide array of antimicrobial peptides to restrain the growth of various microbes. In the case of microbial infection, macrophages and monocytes constitute the first line of defense by producing a wide array of proinflammatory cytokines and chemokines. This process is triggered either by pathogen-associated molecular pattern molecules (such as bacterial endotoxin) or damage-associated molecular pattern molecules (such as HMGB1). In light of our findings that a sweat gland-derived antimicrobial peptide, dermcidin, affected both pathogen-associated molecular pattern and damage-associated molecular pattern-induced cytokines/chemokines by macrophages/monocytes, we propose that dermcidin may play an important role in the regulation of the innate immune responses to infection and injury. Future investigations are warranted to further test this understudied hypothesis in both preclinical and clinical settings.

  16. Tuning cell adhesion on polymeric and nanocomposite surfaces: Role of topography versus superhydrophobicity

    Energy Technology Data Exchange (ETDEWEB)

    Zangi, Sepideh [Department of Chemical Engineering, Shahrood Branch, Islamic Azad University, P.O. Box 36155-163, Shahrood (Iran, Islamic Republic of); Hejazi, Iman [Department of Polymer Engineering & Color Technology, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Seyfi, Javad, E-mail: Jseyfi@gmail.com [Department of Chemical Engineering, Shahrood Branch, Islamic Azad University, P.O. Box 36155-163, Shahrood (Iran, Islamic Republic of); Hejazi, Ehsan [Department of Clinical Nutrition and Dietetics, Faculty of Nutrition Sciences and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of); Khonakdar, Hossein Ali [Department of Polymer Engineering, Faculty of Engineering, South Tehran Branch, Islamic Azad University, P.O. Box 19585-466, Tehran (Iran, Islamic Republic of); Davachi, Seyed Mohammad [School of Chemical Engineering, University of Tehran, P.O. Box 11155-4563, Tehran (Iran, Islamic Republic of)

    2016-06-01

    Development of surface modification procedures which allow tuning the cell adhesion on the surface of biomaterials and devices is of great importance. In this study, the effects of different topographies and wettabilities on cell adhesion behavior of polymeric surfaces are investigated. To this end, an improved phase separation method was proposed to impart various wettabilities (hydrophobic and superhydrophobic) on polypropylene surfaces. Surface morphologies and compositions were characterized by scanning electron microscopy and X-ray photoelectron spectroscopy, respectively. Cell culture was conducted to evaluate the adhesion of 4T1 mouse mammary tumor cells. It was found that processing conditions such as drying temperature is highly influential in cell adhesion behavior due to the formation of an utterly different surface topography. It was concluded that surface topography plays a more significant role in cell adhesion behavior rather than superhydrophobicity since the nano-scale topography highly inhibited the cell adhesion as compared to the micro-scale topography. Such cell repellent behavior could be very useful in many biomedical devices such as those in drug delivery and blood contacting applications as well as biosensors. - Highlights: • A novel method is presented for fabrication of superhydrophobic surfaces. • The presence of nanoparticles in non-solvent bath notably promoted phase separation. • Topography had a more notable impact on cell adhesion than superhydrophobicity. • Nano-scale topographical features highly impeded cell adhesion on polymer surfaces.

  17. Structure activity relationship modelling of milk protein-derived peptides with dipeptidyl peptidase IV (DPP-IV) inhibitory activity.

    Science.gov (United States)

    Nongonierma, Alice B; FitzGerald, Richard J

    2016-05-01

    Quantitative structure activity type models were developed in an attempt to predict the key features of peptide sequences having dipeptidyl peptidase IV (DPP-IV) inhibitory activity. The models were then employed to help predict the potential of peptides, which are currently reported in the literature to be present in the intestinal tract of humans following milk/dairy product ingestion, to act as inhibitors of DPP-IV. Two models (z- and v-scale) for short (2-5 amino acid residues) bovine milk peptides, behaving as competitive inhibitors of DPP-IV, were developed. The z- and the v-scale models (p<0.05, R(2) of 0.829 and 0.815, respectively) were then applied to 56 milk protein-derived peptides previously reported in the literature to be found in the intestinal tract of humans which possessed a structural feature of DPP-IV inhibitory peptides (P at the N2 position). Ten of these peptides were synthetized and tested for their in vitro DPP-IV inhibitory properties. There was no agreement between the predicted and experimentally determined DPP-IV half maximal inhibitory concentrations (IC50) for the competitive peptide inhibitors. However, the ranking for DPP-IV inhibitory potency of the competitive peptide inhibitors was conserved. Furthermore, potent in vitro DPP-IV inhibitory activity was observed with two peptides, LPVPQ (IC50=43.8±8.8μM) and IPM (IC50=69.5±8.7μM). Peptides present within the gastrointestinal tract of human may have promise for the development of natural DPP-IV inhibitors for the management of serum glucose.

  18. Effects of wall shear stress and its gradient on tumor cell adhesion in curved microvessels.

    Science.gov (United States)

    Yan, W W; Cai, B; Liu, Y; Fu, B M

    2012-05-01

    Tumor cell adhesion to vessel walls in the microcirculation is one critical step in cancer metastasis. In this paper, the hypothesis that tumor cells prefer to adhere at the microvessels with localized shear stresses and their gradients, such as in the curved microvessels, was examined both experimentally and computationally. Our in vivo experiments were performed on the microvessels (post-capillary venules, 30-50 μm diameter) of rat mesentery. A straight or curved microvessel was cannulated and perfused with tumor cells by a glass micropipette at a velocity of ~1mm/s. At less than 10 min after perfusion, there was a significant difference in cell adhesion to the straight and curved vessel walls. In 60 min, the averaged adhesion rate in the curved vessels (n = 14) was ~1.5-fold of that in the straight vessels (n = 19). In 51 curved segments, 45% of cell adhesion was initiated at the inner side, 25% at outer side, and 30% at both sides of the curved vessels. To investigate the mechanical mechanism by which tumor cells prefer adhering at curved sites, we performed a computational study, in which the fluid dynamics was carried out by the lattice Boltzmann method , and the tumor cell dynamics was governed by the Newton's law of translation and rotation. A modified adhesive dynamics model that included the influence of wall shear stress/gradient on the association/dissociation rates of tumor cell adhesion was proposed, in which the positive wall shear stress/gradient jump would enhance tumor cell adhesion while the negative wall shear stress/gradient jump would weaken tumor cell adhesion. It was found that the wall shear stress/gradient, over a threshold, had significant contribution to tumor cell adhesion by activating or inactivating cell adhesion molecules. Our results elucidated why the tumor cell adhesion prefers to occur at the positive curvature of curved microvessels with very low Reynolds number (in the order of 10(-2)) laminar flow.

  19. [Derivatives of N-amidinoproline and their use in conventional and solid phase peptide synthesis].

    Science.gov (United States)

    Burov, S V; Moskalenko, Iu E; Leko, M V; Dorosh, M Iu; Panarin, E F

    2006-01-01

    N-Amidinoproline, a hybrid structure modeling key features of the Arg-Pro sequence, was synthesized. The activation of carboxyl group of free N-amidinoproline was found to result in the formation of a cyclic side product, whose structure was confirmed by ESI MS, 1H NMR, and 13C NMR spectra. The preparation of N-(mesitylenesulfonylamidino)-L-proline using the mesitylenesulfonyl derivative of 2-methylisourea was demonstrated to be accompanied by partial racemization. The target product was synthesized by modification of N-amidinoproline by mesitylenesulfonyl chloride. The possibility of using N-amidinoproline in the N-terminal modification of a peptide chain was shown by the example of synthesis of an analogue of the 95-98 fragment of fibrinogen alpha chain.

  20. Regulation of cell-cell adhesion by Rap1.

    Science.gov (United States)

    Fujita, Yasuyuki; Hogan, Catherine; Braga, Vania M M

    2006-01-01

    Rap1 has been implicated in the regulation of morphogenesis and cell-cell contacts in vivo (Asha et al., 1999; Hariharan et al., 1991; Knox and Brown, 2002) and in vitro (Hogan et al., 2004; Price et al., 2004). Among cell-cell adhesion molecules regulated by Rap1 is cadherin, a calcium-dependent adhesive receptor. Assembly of cadherin-mediated cell-cell contacts triggers Rap1 activation, and Rap function is necessary for the stability of cadherins at junctions (Hogan et al., 2004; Price et al., 2004). Here we describe assays to access the effects of Rap1 on cadherin-dependent adhesion in epithelia, in particular the method used for Rap1 localization, activation, and function modulation by microinjection. We focus on controls and culture conditions to determine the specificity of the phenotype with respect to cadherin receptors. This is important, because different receptors that accumulate at sites of cell-cell contacts are also able to activate Rap1 (Fukuyama et al., 2005; Mandell et al., 2005).

  1. Factors affecting antimicrobial activity of MUC7 12-mer, a human salivary mucin-derived peptide

    Directory of Open Access Journals (Sweden)

    Bobek Libuse A

    2007-11-01

    Full Text Available Abstract Background MUC7 12-mer (RKSYKCLHKRCR, a cationic antimicrobial peptide derived from the human low-molecular-weight salivary mucin MUC7, possesses potent antimicrobial activity in vitro. In order to evaluate the potential therapeutic application of the MUC7 12-mer, we examined the effects of mono- and divalent cations, EDTA, pH, and temperature on its antimicrobial activity. Methods Minimal Inhibitory Concentrations (MICs were determined using a liquid growth inhibition assay in 96-well microtiter plates. MUC7 12-mer was added at concentrations of 1.56–50 μM. MICs were determined at three endpoints: MIC-0, MIC-1, and MIC-2 (the lowest drug concentration showing 10%, 25% and 50% of growth, respectively. To examine the effect of salts or EDTA, a checkerboard microdilution technique was used. Fractional inhibitory concentration index (FICi was calculated on the basis of MIC-0. The viability of microbial cells treated with MUC7 12-mer in the presence of sodium or potassium was also determined by killing assay or flow cytometry. Results The MICs of MUC7 12-mer against organisms tested ranged from 6.25–50 μM. For C. albicans, antagonism (FICi 4.5 was observed for the combination of MUC7 12-mer and calcium; however, there was synergism (FICi 0.22 between MUC7 12-mer and EDTA, and the synergism was retained in the presence of calcium at its physiological concentration (1–2 mM. No antagonism but additivity or indifference (FICi 0.55–2.5 was observed for the combination of MUC7 12-mer and each K+, Na+, Mg2+, or Zn2+. MUC7 12-mer peptide (at 25 μM also exerted killing activity in the presence of NaCl, (up to 25 mM for C. albicans and up to 150 mM for E. coli, a physiological concentration of sodium in the oral cavity and serum, respectively and retained candidacidal activity in the presence of KCl (up to 40 mM. The peptide exhibited higher inhibitory activity against C. albicans at pH 7, 8, and 9 than at pH 5 and 6, and temperature up to

  2. Nutritional value of D-amino acids, D-peptides, and amino acid derivatives in mice.

    Science.gov (United States)

    Friedman, Mendel; Levin, Carol E

    2012-01-01

    This paper describes a method for determining the nutritional value of D-amino acids, D-peptides, and amino acid derivatives using a growth assay in mice fed a synthetic all-amino acid diet. A large number of experiments were carried out in which a molar equivalent of the test compound replaced a nutritionally essential amino acid such as L-lysine (L-Lys), L-methionine (L-Met), L -phenylalanine (L-Phe), and L-tryptophan (L-Trp) as well as the semi-essential amino acids L-cysteine (L-Cys) and L-tyrosine (L-Tyr). The results show wide-ranging variations in the biological utilization of test substances. The method is generally applicable to the determination of the biological utilization and safety of any amino acid derivative as a potential nutritional source of the corresponding L-amino acid. Because the organism is forced to use the D-amino acid or amino acid derivative as the sole source of the essential or semi-essential amino acid being replaced, and because a free amino acid diet allows better control of composition, the use of all-amino acid for such determinations may be preferable to protein-based diets.

  3. Characterization of Spontaneous Immune Responses against Long Peptides Derived from Bcl-X(L) in Cancer Patients Using Elispot

    DEFF Research Database (Denmark)

    Svane, Inge Marie; Straten, Per thor; Andersen, Mads Hald;

    2012-01-01

    In recent years we and others have used the ELISPOT assay successfully to identify novel tumor antigens by the characterization of spontaneous HLA class I restricted immune responses against a number of minimal 9–10 amino acid long peptide epitopes. In the present study, we examined the capabilit....... In conclusion several long BCL-X(L) derived peptide epitopes exist, which may be used in anti-cancer immunity. Furthermore, the ELISPOT assay offers an attractive and sensitive method for the characterization of spontaneous immune reactivity against long peptides.......In recent years we and others have used the ELISPOT assay successfully to identify novel tumor antigens by the characterization of spontaneous HLA class I restricted immune responses against a number of minimal 9–10 amino acid long peptide epitopes. In the present study, we examined the capability...... of using longer peptides when scrutinizing Peripheral Blood Mononuclear Cells (PMBC) from melanoma patients for spontaneous immunity by means of ELISPOT IFN-γ secretion assay. To this end, we examined PBMC for the presence of specific T-cell responses against long peptides derived from the tumor associated...

  4. A Tetrameric Peptide Derived from Bovine Lactoferricin Exhibits Specific Cytotoxic Effects against Oral Squamous-Cell Carcinoma Cell Lines

    Science.gov (United States)

    Solarte, Víctor A.; Rosas, Jaiver E.; Rivera, Zuly J.; Arango-Rodríguez, Martha L.; García, Javier E.; Vernot, Jean-Paul

    2015-01-01

    Several short linear peptides derived from cyclic bovine lactoferricin were synthesized and tested for their cytotoxic effect against the oral cavity squamous-cell carcinoma (OSCC) cell lines CAL27 and SCC15. As a control, an immortalized and nontumorigenic cell line, Het-1A, was used. Linear peptides based on the RRWQWR core sequence showed a moderate cytotoxic effect and specificity towards tumorigenic cells. A tetrameric peptide, LfcinB(20–25)4, containing the RRWQWR motif, exhibited greater cytotoxic activity (>90%) in both OSCC cell lines compared to the linear lactoferricin peptide or the lactoferrin protein. Additionally, this tetrameric peptide showed the highest specificity towards tumorigenic cells among the tested peptides. Interestingly, this effect was very fast, with cell shrinkage, severe damage to cell membrane permeability, and lysis within one hour of treatment. Our results are consistent with a necrotic effect rather than an apoptotic one and suggest that this tetrameric peptide could be considered as a new candidate for the therapeutic treatment of OSCC. PMID:26609531

  5. Angiotensin I-converting enzyme inhibitor peptides derived from the endostatin-containing NC1 fragment of human collagen XVIII.

    Science.gov (United States)

    Farias, Shirley L; Sabatini, Regiane A; Sampaio, Tatiana C; Hirata, Izaura Y; Cezari, Maria Helena S; Juliano, Maria A; Sturrock, Edward D; Carmona, Adriana K; Juliano, Luiz

    2006-05-01

    Extracellular matrix and soluble plasma proteins generate peptides that regulate biological activities such as cell growth, differentiation and migration. Bradykinin, a peptide released from kininogen by kallikreins, stimulates vasodilatation and endothelial cell proliferation. Various classes of substances can potentiate these biological actions of bradykinin. Among them, the best studied are bradykinin potentiating peptides (BPPs) derived from snake venom, which can also strongly inhibit angiotensin I-converting enzyme (ACE) activity. We identified and synthesized sequences resembling BPPs in the vicinity of potential proteolytic cleavage sites in the collagen XVIII molecule, close to endostatin. These peptides were screened as inhibitors of human recombinant wild-type ACE containing two intact functional domains; two full-length ACE mutants containing only a functional C- or N-domain catalytic site; and human testicular ACE, a natural form of the enzyme that only contains the C-domain. The BPP-like peptides inhibited ACE in the micromolar range and interacted preferentially with the C-domain. The proteolytic activity involved in the release of BPP-like peptides was studied in human serum and human umbilical-vein endothelial cells. The presence of enzymes able to release these peptides in blood led us to speculate on a physiological mechanism for the control of ACE activities.

  6. A Tetrameric Peptide Derived from Bovine Lactoferricin Exhibits Specific Cytotoxic Effects against Oral Squamous-Cell Carcinoma Cell Lines

    Directory of Open Access Journals (Sweden)

    Víctor A. Solarte

    2015-01-01

    Full Text Available Several short linear peptides derived from cyclic bovine lactoferricin were synthesized and tested for their cytotoxic effect against the oral cavity squamous-cell carcinoma (OSCC cell lines CAL27 and SCC15. As a control, an immortalized and nontumorigenic cell line, Het-1A, was used. Linear peptides based on the RRWQWR core sequence showed a moderate cytotoxic effect and specificity towards tumorigenic cells. A tetrameric peptide, LfcinB(20–254, containing the RRWQWR motif, exhibited greater cytotoxic activity (>90% in both OSCC cell lines compared to the linear lactoferricin peptide or the lactoferrin protein. Additionally, this tetrameric peptide showed the highest specificity towards tumorigenic cells among the tested peptides. Interestingly, this effect was very fast, with cell shrinkage, severe damage to cell membrane permeability, and lysis within one hour of treatment. Our results are consistent with a necrotic effect rather than an apoptotic one and suggest that this tetrameric peptide could be considered as a new candidate for the therapeutic treatment of OSCC.

  7. Design and evaluation of antimalarial peptides derived from prediction of short linear motifs in proteins related to erythrocyte invasion.

    Directory of Open Access Journals (Sweden)

    Alessandra Bianchin

    Full Text Available The purpose of this study was to investigate the blood stage of the malaria causing parasite, Plasmodium falciparum, to predict potential protein interactions between the parasite merozoite and the host erythrocyte and design peptides that could interrupt these predicted interactions. We screened the P. falciparum and human proteomes for computationally predicted short linear motifs (SLiMs in cytoplasmic portions of transmembrane proteins that could play roles in the invasion of the erythrocyte by the merozoite, an essential step in malarial pathogenesis. We tested thirteen peptides predicted to contain SLiMs, twelve of them palmitoylated to enhance membrane targeting, and found three that blocked parasite growth in culture by inhibiting the initiation of new infections in erythrocytes. Scrambled peptides for two of the most promising peptides suggested that their activity may be reflective of amino acid properties, in particular, positive charge. However, one peptide showed effects which were stronger than those of scrambled peptides. This was derived from human red blood cell glycophorin-B. We concluded that proteome-wide computational screening of the intracellular regions of both host and pathogen adhesion proteins provides potential lead peptides for the development of anti-malarial compounds.

  8. Aggregation of peptides in soy protein isolate hydrolysates : the individual contributions of glycinin- and ß-conglycinin-derived peptides

    NARCIS (Netherlands)

    Kuipers, B.J.H.

    2007-01-01

    Keywords: Soy proteins, glycinin, β-conglycinin, enzymatic hydrolysis, peptides, aggregation, gelation, identification, mass-spectrometry, mappingThe aim of the work presented in this thesis is to understand howlimited e

  9. Aggregation of peptides in soy protein isolate hydrolysates : the individual contributions of glycinin- and ß-conglycinin-derived peptides

    NARCIS (Netherlands)

    Kuipers, B.J.H.

    2007-01-01

    Keywords: Soy proteins, glycinin, β-conglycinin, enzymatic hydrolysis, peptides, aggregation, gelation, identification, mass-spectrometry, mappingThe aim of the work presented in this thesis is to understand howlimited

  10. TAP mediates import of Mycobacterium tuberculosis-derived peptides into phagosomes and facilitates loading onto HLA-I.

    Directory of Open Access Journals (Sweden)

    Melanie J Harriff

    Full Text Available Processing and presentation of antigen on MHC-I class I molecules serves to present peptides derived from cytosolic proteins to CD8(+ T cells. Infection with bacteria that remain in phagosomal compartments, such as Mycobacterium tuberculosis (Mtb, provides a challenge to this immune recognition as bacterial proteins are segregated from the cytosol. Previously we identified the Mtb phagosome itself as an organelle capable of loading MHC Class I molecules with Mtb antigens. Here, we find that the TAP transporter, responsible for importing peptides into the ER for loading in Class I molecules, is both present and functional in Mtb phagosomes. Furthermore, we describe a novel peptide reagent, representing the N-terminal domain of the bovine herpes virus UL49.5 protein, which is capable of specifically inhibiting the lumenal face of TAP. Together, these results provide insight into the mechanism by which peptides from intra-phagosomal pathogens are loaded onto Class I molecules.

  11. ProSAAS-derived peptides are colocalized with neuropeptide Y and function as neuropeptides in the regulation of food intake.

    Directory of Open Access Journals (Sweden)

    Jonathan H Wardman

    Full Text Available ProSAAS is the precursor of a number of peptides that have been proposed to function as neuropeptides. Because proSAAS mRNA is highly expressed in the arcuate nucleus of the hypothalamus, we examined the cellular localization of several proSAAS-derived peptides in the mouse hypothalamus and found that they generally colocalized with neuropeptide Y (NPY, but not α-melanocyte stimulating hormone. However, unlike proNPY mRNA, which is upregulated by food deprivation in the mediobasal hypothalamus, neither proSAAS mRNA nor proSAAS-derived peptides were significantly altered by 1-2 days of food deprivation in wild-type mice. Furthermore, while proSAAS mRNA levels in the mediobasal hypothalamus were significantly lower in Cpe(fat/fat mice as compared to wild-type littermates, proNPY mRNA levels in the mediobasal hypothalamus and in other subregions of the hypothalamus were not significantly different between wild-type and Cpe(fat/fat mice. Intracerebroventricular injections of antibodies to two proSAAS-derived peptides (big LEN and PEN significantly reduced food intake in fasted mice, while injections of antibodies to two other proSAAS-derived peptides (little LEN and little SAAS did not. Whole-cell patch clamp recordings of parvocellular neurons in the hypothalamic paraventricular nucleus, a target of arcuate NPY projections, showed that big LEN produced a rapid and reversible inhibition of synaptic glutamate release that was spike independent and abolished by blocking postsynaptic G protein activity, suggesting the involvement of a postsynaptic G protein-coupled receptor and the release of a retrograde synaptic messenger. Taken together with previous studies, these findings support a role for proSAAS-derived peptides such as big LEN as neuropeptides regulating food intake.

  12. Experimental and computational investigation of the effect of hydrophobicity on aggregation and osteoinductive potential of BMP-2-derived peptide in a hydrogel matrix.

    Science.gov (United States)

    Moeinzadeh, Seyedsina; Barati, Danial; Sarvestani, Samaneh K; Karimi, Tahereh; Jabbari, Esmaiel

    2015-01-01

    An attractive approach to reduce the undesired side effects of bone morphogenetic proteins (BMPs) in regenerative medicine is to use osteoinductive peptide sequences derived from BMPs. Although the structure and function of BMPs have been studied extensively, there is limited data on structure and activity of BMP-derived peptides immobilized in hydrogels. The objective of this work was to investigate the effect of concentration and hydrophobicity of the BMP-2 peptide, corresponding to residues 73-92 of the knuckle epitope of BMP-2 protein, on peptide aggregation and osteogenic differentiation of human mesenchymal stem cells encapsulated in a polyethylene glycol (PEG) hydrogel. The peptide hydrophobicity was varied by capping PEG chain ends with short lactide segments. The BMP-2 peptide with a positive index of hydrophobicity had a critical micelle concentration (CMC) and formed aggregates in aqueous solution. Based on simulation results, there was a slight increase in the concentration of free peptide in solution with 1000-fold increase in peptide concentration. The dose-osteogenic response curve of the BMP-2 peptide was in the 0.0005-0.005 mM range, and osteoinductive potential of the BMP-2 peptide was significantly less than that of BMP-2 protein even at 1000-fold higher concentrations, which was attributed to peptide aggregation. Further, the peptide or PEG-peptide aggregates had significantly higher interaction energy with the cell membrane compared with the free peptide, which led to a higher nonspecific interaction with the cell membrane and loss of osteoinductive potential. Conjugation of the BMP-2 peptide to PEG increased CMC and osteoinductive potential of the peptide whereas conjugation to lactide-capped PEG reduced CMC and osteoinductive potential of the peptide. Experimental and simulation results revealed that osteoinductive potential of the BMP-2 peptide is correlated with its CMC and the free peptide concentration in aqueous medium and not the

  13. Identification of a Novel P190-Derived Breakpoint Peptide Suitable for Peptide Vaccine Therapeutic Approach in Ph+ Acute Lymphoblastic Leukemia Patients

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    Micaela Ippoliti

    2012-01-01

    Full Text Available Ph+ acute lymphoblastic leukemia (Ph+ ALL is a high-risk acute leukemia with poor prognosis, in which the specific t(9;22(q34;q11 translocation results in a chimeric bcr-abl (e1a2 breakpoint and in a 190 KD protein (p190 with constitutive tyrosine kinase activity. The advent of first- and second-generation tyrosine kinase inhibitors (TKIs improved the short-term outcome of Ph+ ALL patients not eligible for allo-SCT; yet disease recurrence is almost inevitable. Peptides derived from p190-breakpoint area are leukemia-specific antigens that may mediate an antitumor response toward p190+ leukemia cells. We identified one peptide named p190-13 able to induce in vitro peptide-specific CD4+ T cell proliferation in Ph+ ALL patients in complete remission during TKIs. Thus this peptide appears a good candidate for developing an immune target vaccine strategy possibly synergizing with TKIs for remission maintenance.

  14. Glycosynapses: microdomains controlling carbohydrate-dependent cell adhesion and signaling

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    Senitiroh Hakomori

    2004-09-01

    Full Text Available The concept of microdomains in plasma membranes was developed over two decades, following observation of polarity of membrane based on clustering of specific membrane components. Microdomains involved in carbohydrate-dependent cell adhesion with concurrent signal transduction that affect cellular phenotype are termed "glycosynapse". Three types of glycosynapse have been distinguished: "type 1" having glycosphingolipid associated with signal transducers (small G-proteins, cSrc, Src family kinases and proteolipids; "type 2" having O-linked mucin-type glycoprotein associated with Src family kinases; and "type 3" having N-linked integrin receptor complexed with tetraspanin and ganglioside. Different cell types are characterized by presence of specific types of glycosynapse or their combinations, whose adhesion induces signal transduction to either facilitate or inhibit signaling. E.g., signaling through type 3 glycosynapse inhibits cell motility and differentiation. Glycosynapses are distinct from classically-known microdomains termed "caveolae", "caveolar membrane", or more recently "lipid raft", which are not involved in carbohydrate-dependent cell adhesion. Type 1 and type 3 glycosynapses are resistant to cholesterol-binding reagents, whereas structure and function of "caveolar membrane" or "lipid raft" are disrupted by these reagents. Various data indicate a functional role of glycosynapses during differentiation, development, and oncogenic transformation.O conceito de microdomínios em membrana plasmática foi desenvolvido há mais de duas décadas, após a observação da polaridade da membrana baseada no agrupamento de componentes específicos da membrana. Microdomínios envolvidos na adesão celular dependente de carboidrato, com transdução de sinal que afeta o fenótipo celular são denominados ''glicosinapses''. Três tipos de glicosinapse foram observados: ''tipo 1'' que possue glicoesfingolipídio associado com transdutores de sinal

  15. Inflammatory mediators and cell adhesion molecules as indicators of severity of atherosclerosis: the Rotterdam Study

    NARCIS (Netherlands)

    M.P.M. de Maat (Moniek); M.L. Bots (Michiel); M.M.B. Breteler (Monique); J. Meijer (John); A.J. Kiliaan (Amanda); J.C.M. Witteman (Jacqueline); A. Hofman (Albert)

    2002-01-01

    textabstractInflammatory mediators and soluble cell adhesion molecules predict cardiovascular events. It is not clear whether they reflect the severity of underlying atherosclerotic disease. Within the Rotterdam Study, we investigated the associations of C-reactive protein (CRP), i

  16. Activated leukocyte cell adhesion molecule and prognosis in acute ischemic stroke

    DEFF Research Database (Denmark)

    Smedbakken, Linda; Jensen, Jesper K; Hallén, Jonas

    2011-01-01

    Biomarkers predicting mortality and functional outcome in stroke may be clinically helpful in identification of patients likely to benefit from intervention. Activated leukocyte cell adhesion molecule (ALCAM) is upregulated during neuroinflammation; we investigated whether ALCAM concentrations...

  17. Vascular Basement Membrane-derived Multifunctional Peptide, a Novel Inhibitor of Angiogenesis and Tumor Growth

    Institute of Scientific and Technical Information of China (English)

    Jian-Guo CAO; Shu-Ping PENG; Li SUN; Hui LI; Li WANG; Han-Wu DENG

    2006-01-01

    Vascular basement membrane-derived multifunctional peptide (VBMDMP) gene (fusion gene of the human immunoglobulin G3 upper hinge region and two tumstatin-derived fragments) obtained by chemical synthesis was cloned into vector pUC 19, and introduced into the expression vector pGEX-4T-1 to construct a prokaryotic expression vector pGEX-4T-1-VBMDMP. Recombinant VBMDMP produced in Escherichia coli has been shown to have significant activity of antitumor growth and antimetastasis in Lewis lung carcinoma transplanted into mouse C57B1/6. In the present study, we have studied the ability of rVBMDMP to inhibit endothelial cell tube formation and proliferation, to induce apoptosis in vitro, and to suppress tumor growth in vivo. The experimental results showed that rVBMDMP potently inhibited proliferation of human endothelial (HUVEC-12) cells and human colon cancer (SW480) cells in vitro, with no inhibition of proliferation in Chinese hamster ovary (CHO-K1) cells. rVBMDMP also significantly inhibited human endothelial cell tube formation and suppressed tumor growth of SW480 cells in a mouse xenograft model. These results suggest that rVBMDMP is a powerful therapeutic agent for suppressing angiogenesis and tumor growth.

  18. Micelle bound structure and DNA interaction of brevinin-2-related peptide, an antimicrobial peptide derived from frog skin.

    Science.gov (United States)

    Bandyopadhyay, Susmita; Ng, Boon Yee; Chong, Charmaine; Lim, Ming Zhen; Gill, Sonia Kiran; Lee, Ke Hui; Sivaraman, J; Chatterjee, Chiradip

    2014-10-01

    Brevinin-2-related peptide (BR-II), a novel antimicrobial peptide isolated from the skin of frog, Rana septentrionalis, shows a broad spectrum of antimicrobial activity with low haemolytic activity. It has also been shown to have antiviral activity, specifically to protect cells from infection by HIV-1. To understand the active conformation of the BR-II peptide in membranes, we have investigated the interaction of BR-II with the prokaryotic and eukaryotic membrane-mimetic micelles such as sodium dodecylsulfate (SDS) and dodecylphosphocholine (DPC), respectively. The interactions were studied using fluorescence and circular dichroism (CD) spectroscopy. Fluorescence experiments revealed that the N-terminus tryptophan residue of BR-II interacts with the hydrophobic core of the membrane mimicking micelles. The CD results suggest that interactions with membrane-mimetic micelles induce an α-helix conformation in BR-II. We have also determined the solution structures of BR-II in DPC and SDS micelles using NMR spectroscopy. The structural comparison of BR-II in the presence of SDS and DPC micelles showed significant conformational changes in the residues connecting the N-terminus and C-terminus helices. The ability of BR-II to bind DNA was elucidated by agarose gel retardation and fluorescence experiments. The structural differences of BR-II in zwitterionic versus anionic membrane mimics and the DNA binding ability of BR-II collectively contribute to the general understanding of the pharmacological specificity of this peptide towards prokaryotic and eukaryotic membranes and provide insights into its overall antimicrobial mechanism.

  19. Progress of Research on Food-Derived Peptide%食源性肽研究进展

    Institute of Scientific and Technical Information of China (English)

    蔡木易

    2012-01-01

    Food-derived peptides are new kinds of proteolytic products derived from food proteins by en- zyme hydrolysis, separation, and purification. This article reviewed the present researches on nutrition and health function, production method, evaluation and reeognization of the food-derived peptides, and current situation of quality standard. Also, the traditional food contained bioactive peptides and the termi- nal food that has been commercialized were overviewed and summarized. Finally, the application prospect of food-derived peptides was described.%食源性肽是以食用蛋白为原料,经过酶解、分离、纯化等制成的新型蛋白水解产品.阐述了食源性肽的营养保健功能和生产方法、食源性肽类产品的评价、认可情况及质量标准的研究现状,并对含有生物活性肽的传统食品以及已商业化的食源性肽类终端食品进行了概述和总结,最后对其应用前景进行了展望.

  20. The fibrin-derived peptide Bbeta(15-42) significantly attenuates ischemia-reperfusion injury in a cardiac transplant model.

    NARCIS (Netherlands)

    Wiedemann, D.; Schneeberger, S.; Friedl, P.H.A.; Zacharowski, K.; Wick, N.; Boesch, F.; Margreiter, R.; Laufer, G.; Petzelbauer, P.; Semsroth, S.

    2010-01-01

    BACKGROUND: The inflammatory response after prolonged ischemia and subsequent reperfusion leads to increased risk of primary organ dysfunction after cardiac transplantation. It has been demonstrated that the fibrin-derived peptide Bbeta(15-42) (also called FX06) reduces infarct size in coronary arte

  1. Constitutive expression of transgenes encoding derivatives of the synthetic antimicrobial peptide BP100: impact on rice host plant fitness

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    Nadal Anna

    2012-09-01

    Full Text Available Abstract Background The Biopeptide BP100 is a synthetic and strongly cationic α-helical undecapeptide with high, specific antibacterial activity against economically important plant-pathogenic bacteria, and very low toxicity. It was selected from a library of synthetic peptides, along with other peptides with activities against relevant bacterial and fungal species. Expression of the BP100 series of peptides in plants is of major interest to establish disease-resistant plants and facilitate molecular farming. Specific challenges were the small length, peptide degradation by plant proteases and toxicity to the host plant. Here we approached the expression of the BP100 peptide series in plants using BP100 as a proof-of-concept. Results Our design considered up to three tandemly arranged BP100 units and peptide accumulation in the endoplasmic reticulum (ER, analyzing five BP100 derivatives. The ER retention sequence did not reduce the antimicrobial activity of chemically synthesized BP100 derivatives, making this strategy possible. Transformation with sequences encoding BP100 derivatives (bp100der was over ten-fold less efficient than that of the hygromycin phosphotransferase (hptII transgene. The BP100 direct tandems did not show higher antimicrobial activity than BP100, and genetically modified (GM plants constitutively expressing them were not viable. In contrast, inverted repeats of BP100, whether or not elongated with a portion of a natural antimicrobial peptide (AMP, had higher antimicrobial activity, and fertile GM rice lines constitutively expressing bp100der were produced. These GM lines had increased resistance to the pathogens Dickeya chrysanthemi and Fusarium verticillioides, and tolerance to oxidative stress, with agronomic performance comparable to untransformed lines. Conclusions Constitutive expression of transgenes encoding short cationic α-helical synthetic peptides can have a strong negative impact on rice fitness. However, GM

  2. The cell adhesion molecule Fasciclin2 regulates brush border length and organization in Drosophila renal tubules

    DEFF Research Database (Denmark)

    Halberg, Kenneth Agerlin; Rainey, Stephanie M.; Veland, Iben Rønn

    2016-01-01

    Multicellular organisms rely on cell adhesion molecules to coordinate cell-cell interactions, and to provide navigational cues during tissue formation. In Drosophila, Fasciclin 2 (Fas2) has been intensively studied due to its role in nervous system development and maintenance; yet, Fas2 is most...... role for this well-known cell adhesion molecule, and propose that Fas2-mediated intermicrovillar homophilic adhesion complexes help stabilize the brush border....

  3. A fluorescent glycolipid-binding peptide probe traces cholesterol dependent microdomain-derived trafficking pathways.

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    Steffen Steinert

    Full Text Available BACKGROUND: The uptake and intracellular trafficking of sphingolipids, which self-associate into plasma membrane microdomains, is associated with many pathological conditions, including viral and toxin infection, lipid storage disease, and neurodegenerative disease. However, the means available to label the trafficking pathways of sphingolipids in live cells are extremely limited. In order to address this problem, we have developed an exogenous, non-toxic probe consisting of a 25-amino acid sphingolipid binding domain, the SBD, derived from the amyloid peptide Abeta, and conjugated by a neutral linker with an organic fluorophore. The current work presents the characterization of the sphingolipid binding and live cell trafficking of this novel probe, the SBD peptide. SBD was the name given to a motif originally recognized by Fantini et al in a number of glycolipid-associated proteins, and was proposed to interact with sphingolipids in membrane microdomains. METHODOLOGY/PRINCIPAL FINDINGS: In accordance with Fantini's model, optimal SBD binding to membranes depends on the presence of sphingolipids and cholesterol. In synthetic membrane binding assays, SBD interacts preferentially with raft-like lipid mixtures containing sphingomyelin, cholesterol, and complex gangliosides in a pH-dependent manner, but is less glycolipid-specific than Cholera toxin B (CtxB. Using quantitative time-course colocalization in live cells, we show that the uptake and intracellular trafficking route of SBD is unlike that of either the non-raft marker Transferrin or the raft markers CtxB and Flotillin2-GFP. However, SBD traverses an endolysosomal route that partially intersects with raft-associated pathways, with a major portion being diverted at a late time point to rab11-positive recycling endosomes. Trafficking of SBD to acidified compartments is strongly disrupted by cholesterol perturbations, consistent with the regulation of sphingolipid trafficking by cholesterol

  4. ANNEXIN A1 N-TERMINAL DERIVED PEPTIDE AC2-26 EXERTS CHEMOKINETIC EFFECTS ON HUMAN NEUTROPHILS

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    Jesmond eDalli

    2012-02-01

    Full Text Available It is postulated that peptides derived from the N-terminal region of Annexin A1, a glucocorticoid-regulated 37-kDa protein, could act as biomimetics of the parent protein. However, recent evidence, amongst which the ability to interact with distinct receptors other then that described for Annexin A1, suggest that these peptides might fulfil other functions at variance to those reported for the parent protein. Here we tested the ability of peptide Ac2-26 to induce chemotaxis of human neutrophils, showing that this peptide can elicit responses comparable to those produced by the canonical activator formyl-Met-Leu-Phe (or FMLP. However, whilst disruption of the chemical gradient abolished the FMLP response, addition of peptide Ac2-26 in the top well of the chemotaxis chamber did not affect (10 µM or augmented (at 30 µM the neutrophil locomotion to the bottom well, as elicited by 10 µM peptide Ac2-26. Intriguingly, the sole addition of peptide Ac2-26 in the top wells produced a marked migration of neutrophils. A similar behaviour was observed when human primary monocytes were used. Thus, peptide Ac2-26 is a genuine chemokinetic agent towards human blood leukocytes.Neutralization strategies indicated that engagement of either the GPCR termed FPR1 or its cognate receptor FPR2/ALX was sufficient to sustain peptide Ac2-26 induced neutrophil migration. Similarly, application of pharmacological inhibitors showed that cell locomotion to peptide Ac2-26 was mediated primarily by the ERK, but not the JNK and p38 pathways.In conclusion, we report here novel in vitro properties for peptide Ac2-26, promoting neutrophil and monocyte chemokinesis, a process that may contribute to accelerate the resolution phase of inflammation. Here we postulate that the generation Annexin A1 N-terminal peptides at the site of inflammation may expedite the egress of migrated leukocytes thus promoting the return to homeostasis.

  5. Presence of chromogranin-derived antimicrobial peptides in plasma during coronary artery bypass surgery and evidence of an immune origin of these peptides.

    Science.gov (United States)

    Tasiemski, Aurélie; Hammad, Hamida; Vandenbulcke, Franck; Breton, Christophe; Bilfinger, Thomas J; Pestel, Joel; Salzet, Michel

    2002-07-15

    Chromogranin A (CGA) and chromogranin B (CGB) are acidic proteins stored in secretory organelles of endocrine cells and neurons. In addition to their roles as helper proteins in the packaging of peptides, they may serve as prohormones to generate biologically active peptides such as vasostatin-1 and secretolytin. These molecules derived from CGA and CGB, respectively, possess antimicrobial properties. The present study demonstrates that plasmatic levels of both vasostatin-1 and secretolytin increase during surgery in patients undergoing cardiopulmonary bypass (CPB). Vasostatin-1 and secretolytin, initially present in plasma at low levels, are released just after skin incision. Consequently, they can be added to enkelytin, an antibacterial peptide derived from proenkephalin A, for the panoply of components acting as a first protective barrier against hypothetical invasion of pathogens, which may occur during surgery. CGA and CGB, more commonly viewed as markers for endocrine and neuronal cells, were also found to have an immune origin. RNA messengers coding for CGB were amplified by reverse transcription-polymerase chain reaction in human monocytes, and immunocytochemical analysis by confocal microscopy revealed the presence of CGA or CGB or both in monocytes and neutrophils. A combination of techniques including confocal microscopic analysis, mass spectrometry measurement, and antibacterial tests allowed for the identification of the positive role of interleukin 6 (IL-6) in the secretolytin release from monocytes in vitro. Because IL-6 release is known to be strongly enhanced during CPB, we suggest a possible relationship between IL-6 and the increased level of secretolytin in patients undergoing CPB.

  6. Design Methods of Cell Adhesion Proteins Based on ELISA Usable in-vitro in Gene Therapy

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    E Hosseini

    2016-07-01

    Full Text Available Background & aim: One of the strategies to improve the therapeutic gene is targeting gene therapy. A method which can be considered, is adding code sequences peptide or protein with high tendency to target cells and secreting the therapeutic gene encodes a protein. However, evaluating the effectiveness of such changes in the targeted cell binding protein gene product with the usual therapeutic methods produced in prokaryotic system is directly impossible. The purpose of this study was to evaluate the design methods of cell adhesion proteins based on ELISA usable in-vitro in gene therapy. Methods: In order to target the therapeutic gene Mda-7 by using genetic engineering, peptide coding sequence RGD4C with the tendency to cancerous cell surface integrin were inserted shortly after the artificial signal peptide sequence and the N-terminal coding region of the protein. Then, the modified and unmodified cDNA eukaryotic expression vector pCDNA3.1 were matched. Vectors were transfected in HEK-293 cell line. Then Mda-7 secreted expression levels were measured in cell culture by ELISA. After adjusting the protein concentration of Mda-7 and RGD.Mda-7, in cells transfected media, they were used as a source of protein. Reduce the concentration of these genes was assessed two hours after exposure to the integrin cell lines with HepG2, M21 and lacking integrin Saos-2  were also determined by ELISA. The present study was conducted three times independently.  Data were analyzed using t-test. Results: Statistical analysis of the results suggested that the gene product of the gene product RGD.Mda-7 and Mda-7 to connect to HepG2 cells and M21 were more likely to have integrin. While binding to the cell lines of Saos-2, no significant difference were observed. Conclusions: It seems the present ELISA based method was a suitable strategy for cell attachment assay in gene therapy research.  

  7. Single-cell RNAseq reveals cell adhesion molecule profiles in electrophysiologically defined neurons.

    Science.gov (United States)

    Földy, Csaba; Darmanis, Spyros; Aoto, Jason; Malenka, Robert C; Quake, Stephen R; Südhof, Thomas C

    2016-08-30

    In brain, signaling mediated by cell adhesion molecules defines the identity and functional properties of synapses. The specificity of presynaptic and postsynaptic interactions that is presumably mediated by cell adhesion molecules suggests that there exists a logic that could explain neuronal connectivity at the molecular level. Despite its importance, however, the nature of such logic is poorly understood, and even basic parameters, such as the number, identity, and single-cell expression profiles of candidate synaptic cell adhesion molecules, are not known. Here, we devised a comprehensive list of genes involved in cell adhesion, and used single-cell RNA sequencing (RNAseq) to analyze their expression in electrophysiologically defined interneurons and projection neurons. We compared the cell type-specific expression of these genes with that of genes involved in transmembrane ion conductances (i.e., channels), exocytosis, and rho/rac signaling, which regulates the actin cytoskeleton. Using these data, we identified two independent, developmentally regulated networks of interacting genes encoding molecules involved in cell adhesion, exocytosis, and signal transduction. Our approach provides a framework for a presumed cell adhesion and signaling code in neurons, enables correlating electrophysiological with molecular properties of neurons, and suggests avenues toward understanding synaptic specificity.

  8. Cellular uptake but low permeation of human calcitonin-derived cell penetrating peptides and Tat(47-57) through well-differentiated epithelial models

    DEFF Research Database (Denmark)

    Tréhin, Rachel; Krauss, Ulrike; Beck-Sickinger, Annette G;

    2004-01-01

    To investigate whether cell penetrating peptides (CPP) derived from human calcitonin (hCT) possess, in addition to cellular uptake, the capacity to deliver their cargo through epithelial barriers.......To investigate whether cell penetrating peptides (CPP) derived from human calcitonin (hCT) possess, in addition to cellular uptake, the capacity to deliver their cargo through epithelial barriers....

  9. Spontaneous human squamous cell carcinomas are killed by a human cytotoxic T lymphocyte clone recognizing a wild-type p53-derived peptide

    DEFF Research Database (Denmark)

    Röpke, M; Hald, J; Guldberg, Per

    1996-01-01

    p53 genes, in a L9V/HLA-A2 specific and restricted fashion. Thus, the normal tolerance against endogenously processed p53 protein-derived self-epitopes can be broken by peptide-specific in vitro priming. p53 protein-derived wild-type peptides might thus represent tumor associated target molecules...

  10. High cleavage efficiency of a 2A peptide derived from porcine teschovirus-1 in human cell lines, zebrafish and mice.

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    Jin Hee Kim

    Full Text Available When expression of more than one gene is required in cells, bicistronic or multicistronic expression vectors have been used. Among various strategies employed to construct bicistronic or multicistronic vectors, an internal ribosomal entry site (IRES has been widely used. Due to the large size and difference in expression levels between genes before and after IRES, however, a new strategy was required to replace IRES. A self-cleaving 2A peptide could be a good candidate to replace IRES because of its small size and high cleavage efficiency between genes upstream and downstream of the 2A peptide. Despite the advantages of the 2A peptides, its use is not widespread because (i there are no publicly available cloning vectors harboring a 2A peptide gene and (ii comprehensive comparison of cleavage efficiency among various 2A peptides reported to date has not been performed in different contexts. Here, we generated four expression plasmids each harboring different 2A peptides derived from the foot-and-mouth disease virus, equine rhinitis A virus, Thosea asigna virus and porcine teschovirus-1, respectively, and evaluated their cleavage efficiency in three commonly used human cell lines, zebrafish embryos and adult mice. Western blotting and confocal microscopic analyses revealed that among the four 2As, the one derived from porcine teschovirus-1 (P2A has the highest cleavage efficiency in all the contexts examined. We anticipate that the 2A-harboring cloning vectors we generated and the highest efficiency of the P2A peptide we demonstrated would help biomedical researchers easily adopt the 2A technology when bicistronic or multicistronic expression is required.

  11. ProSAAS-derived peptides are differentially processed and sorted in mouse brain and AtT-20 cells.

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    Jonathan H Wardman

    Full Text Available ProSAAS is the precursor for some of the most abundant peptides found in mouse brain and other tissues, including peptides named SAAS, PEN, and LEN. Both SAAS and LEN are found in big and little forms due to differential processing. Initial processing of proSAAS is mediated by furin (and/or furin-like enzymes and carboxypeptidase D, while the smaller forms are generated by secretory granule prohormone convertases and carboxypeptidase E. In mouse hypothalamus, PEN and big LEN colocalize with neuropeptide Y. In the present study, little LEN and SAAS were detected in mouse hypothalamus but not in cell bodies of neuropeptide Y-expressing neurons. PEN and big LEN show substantial colocalization in hypothalamus, but big LEN and little LEN do not. An antiserum to SAAS that detects both big and little forms of this peptide did not show substantial colocalization with PEN or big LEN. To further study this, the AtT-20 cells mouse pituitary corticotrophic cell line was transfected with rat proSAAS and the distribution of peptides examined. As found in mouse hypothalamus, only some of the proSAAS-derived peptides colocalized with each other in AtT-20 cells. The two sites within proSAAS that are known to be efficiently cleaved by furin were altered by site-directed mutagenesis to convert the P4 Arg into Lys; this change converts the sequences from furin consensus sites into prohormone convertase consensus sites. Upon expression of the mutated form of proSAAS in AtT-20 cells, there was significantly more colocalization of proSAAS-derived peptides PEN and SAAS. Taken together, these results indicate that proSAAS is initially cleaved in the Golgi or trans-Golgi network by furin and/or furin-like enzymes and the resulting fragments are sorted into distinct vesicles and further processed by additional enzymes into the mature peptides.

  12. Are there autoantibodies reacting against citrullinated peptides derived from type I and type II collagens in patients with rheumatoid arthritis?

    Science.gov (United States)

    Koivula, M; Aman, S; Karjalainen, A; Hakala, M; Risteli, J

    2005-01-01

    Objectives: To assess the possible presence in patients with rheumatoid arthritis (RA) of autoantibodies recognising citrullinated peptides derived from type I and II collagens. Methods: Firstly, the binding of four pairs of synthetic peptides (arginine-containing and artificially citrullinated forms) related to different regions of human type II collagen were tested with sera from 120 patients with RA and 81 controls. Secondly, two similar pairs of peptides related to the carboxy terminal telopeptides of the α1 and α2 chains of human type I collagen were tested. Results: 42–53% of the RA sera showed increased binding of arginine peptides related to type II collagen. However, 12 RA sera bound the citrullinated form of the α1(II) telopeptide more strongly than the corresponding arginine peptide. 20 RA sera bound the citrullinated carboxytelopeptide from the α1 chain of type I collagen (α1(I) telopeptide) more strongly than the respective arginine peptide. The correlation between the autoantibodies to type I and II collagen telopeptides was rs = 0.576, pAnti-cyclic citrullinated peptide (anti-CCP) assay was positive in 71/120 (59%) patients with RA. An anti-CCP assay detects a different subgroup of antibodies than anti-telopeptide assays. However, both anti-telopeptide and anti-CCP antibodies were increased in patients with RA. Conclusion: Some patients with RA were identified whose sera contained antibodies that specifically bound citrullinated peptides related to the carboxy terminal telopeptides of the α1 and α2 chains of type I collagen and the α1 chains of type II collagen (sequences YYXA, FYXA, and YMXA, where X stands for citrulline). PMID:16162901

  13. Solution structures, dynamics, and ice growth inhibitory activity of peptide fragments derived from an antarctic yeast protein.

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    Syed Hussinien H Shah

    Full Text Available Exotic functions of antifreeze proteins (AFP and antifreeze glycopeptides (AFGP have recently been attracted with much interest to develop them as commercial products. AFPs and AFGPs inhibit ice crystal growth by lowering the water freezing point without changing the water melting point. Our group isolated the Antarctic yeast Glaciozyma antarctica that expresses antifreeze protein to assist it in its survival mechanism at sub-zero temperatures. The protein is unique and novel, indicated by its low sequence homology compared to those of other AFPs. We explore the structure-function relationship of G. antarctica AFP using various approaches ranging from protein structure prediction, peptide design and antifreeze activity assays, nuclear magnetic resonance (NMR studies and molecular dynamics simulation. The predicted secondary structure of G. antarctica AFP shows several α-helices, assumed to be responsible for its antifreeze activity. We designed several peptide fragments derived from the amino acid sequences of α-helical regions of the parent AFP and they also showed substantial antifreeze activities, below that of the original AFP. The relationship between peptide structure and activity was explored by NMR spectroscopy and molecular dynamics simulation. NMR results show that the antifreeze activity of the peptides correlates with their helicity and geometrical straightforwardness. Furthermore, molecular dynamics simulation also suggests that the activity of the designed peptides can be explained in terms of the structural rigidity/flexibility, i.e., the most active peptide demonstrates higher structural stability, lower flexibility than that of the other peptides with lower activities, and of lower rigidity. This report represents the first detailed report of downsizing a yeast AFP into its peptide fragments with measurable antifreeze activities.

  14. Identification of a human cyclin D1-derived peptide that induces human cytotoxic CD4 T cells.

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    Tao Dao

    Full Text Available Cyclin D1 is over-expressed in various human tumors and therefore can be a potential oncogenic target antigen. However, only a limited number of T cell epitopes has been characterized. We aimed at identifying human cyclin D1-derived peptides that include both CD4 and CD8 T cell epitopes and to test if such multi-epitope peptides could yield improved cytotoxic CD8 T cell responses as well as cytotoxic CD4 T cells. Five HLA-DR.B1-binding peptides containing multiple overlapping CD4 epitopes and HLA-A0201-restricted CD8 T cell epitopes were predicted by computer algorithms. Immunogenicity of the synthetic peptides was assessed by stimulating T cells from healthy donors in vitro and the epitope recognition was measured by IFN-gamma ELISPOT and (51Chromium release assays. A HLA-DR.B1 peptide, designed "DR-1", in which a HLA-A0201-binding epitopes (D1-1 was imbedded, induced CD3 T cell responses against both DR-1 and D1-1 peptides in IFN-gamma ELISPOT assay. This suggested processing of the shorter D1-1 epitope from the DR-1 sequence. However, only DR-1-stimulated CD4 or CD3 T cells possessed cytotoxicity against peptide-pulsed autologous DCs and a cancer cell line, that expresses a high level of cyclin D1. Monoclonal antibody to HLA-DR abrogated the epitope-specific responses of both CD3 and CD4 T cells, demonstrating class II-mediated killing. Our studies suggest a possible role of CD4 T cells in anti-tumor immunity as cytotoxic effectors against HLA-DR expressing cancers and provide a rationale for designing peptide vaccines that include CD4 epitopes.

  15. Tumor imaging and targeting potential of an Hsp70-derived 14-mer peptide.

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    Mathias Gehrmann

    Full Text Available BACKGROUND: We have previously used a unique mouse monoclonal antibody cmHsp70.1 to demonstrate the selective presence of a membrane-bound form of Hsp70 (memHsp70 on a variety of leukemia cells and on single cell suspensions derived from solid tumors of different entities, but not on non-transformed cells or cells from corresponding 'healthy' tissue. This antibody can be used to image tumors in vivo and target them for antibody-dependent cellular cytotoxicity. Tumor-specific expression of memHsp70 therefore has the potential to be exploited for theranostic purposes. Given the advantages of peptides as imaging and targeting agents, this study assessed whether a 14-mer tumor penetrating peptide (TPP; TKDNNLLGRFELSG, the sequence of which is derived from the oligomerization domain of Hsp70 which is expressed on the cell surface of tumor cells, can also be used for targeting membrane Hsp70 positive (memHsp70+ tumor cells, in vitro. METHODOLOGY/PRINCIPAL FINDINGS: The specificity of carboxy-fluorescein (CF- labeled TPP (TPP to Hsp70 was proven in an Hsp70 knockout mammary tumor cell system. TPP specifically binds to different memHsp70+ mouse and human tumor cell lines and is rapidly taken up via endosomes. Two to four-fold higher levels of CF-labeled TPP were detected in MCF7 (82% memHsp70+ and MDA-MB-231 (75% memHsp70+ cells compared to T47D cells (29% memHsp70+ that exhibit a lower Hsp70 membrane positivity. After 90 min incubation, TPP co-localized with mitochondrial membranes in memHsp70+ tumors. Although there was no evidence that any given vesicle population was specifically localized, fluorophore-labeled cmHsp70.1 antibody and TPP preferentially accumulated in the proximity of the adherent surface of cultured cells. These findings suggest a potential association between membrane Hsp70 expression and cytoskeletal elements that are involved in adherence, the establishment of intercellular synapses and/or membrane reorganization. CONCLUSIONS

  16. Conserved roles of the prion protein domains on subcellular localization and cell-cell adhesion.

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    Gonzalo P Solis

    Full Text Available Analyses of cultured cells and transgenic mice expressing prion protein (PrP deletion mutants have revealed that some properties of PrP -such as its ability to misfold, aggregate and trigger neurotoxicity- are controlled by discrete molecular determinants within its protein domains. Although the contributions of these determinants to PrP biosynthesis and turnover are relatively well characterized, it is still unclear how they modulate cellular functions of PrP. To address this question, we used two defined activities of PrP as functional readouts: 1 the recruitment of PrP to cell-cell contacts in Drosophila S2 and human MCF-7 epithelial cells, and 2 the induction of PrP embryonic loss- and gain-of-function phenotypes in zebrafish. Our results show that homologous mutations in mouse and zebrafish PrPs similarly affect their subcellular localization patterns as well as their in vitro and in vivo activities. Among PrP's essential features, the N-terminal leader peptide was sufficient to drive targeting of our constructs to cell contact sites, whereas lack of GPI-anchoring and N-glycosylation rendered them inactive by blocking their cell surface expression. Importantly, our data suggest that the ability of PrP to homophilically trans-interact and elicit intracellular signaling is primarily encoded in its globular domain, and modulated by its repetitive domain. Thus, while the latter induces the local accumulation of PrPs at discrete punctae along cell contacts, the former counteracts this effect by promoting the continuous distribution of PrP. In early zebrafish embryos, deletion of either domain significantly impaired PrP's ability to modulate E-cadherin cell adhesion. Altogether, these experiments relate structural features of PrP to its subcellular distribution and in vivo activity. Furthermore, they show that despite their large evolutionary history, the roles of PrP domains and posttranslational modifications are conserved between mouse and

  17. Measuring cell adhesion forces of primary gastrulating cells from zebrafish using atomic force microscopy.

    Science.gov (United States)

    Puech, Pierre-Henri; Taubenberger, Anna; Ulrich, Florian; Krieg, Michael; Muller, Daniel J; Heisenberg, Carl-Philipp

    2005-09-15

    During vertebrate gastrulation, progenitor cells of different germ layers acquire specific adhesive properties that contribute to germ layer formation and separation. Wnt signals have been suggested to function in this process by modulating the different levels of adhesion between the germ layers, however, direct evidence for this is still lacking. Here we show that Wnt11, a key signal regulating gastrulation movements, is needed for the adhesion of zebrafish mesendodermal progenitor cells to fibronectin, an abundant extracellular matrix component during gastrulation. To measure this effect, we developed an assay to quantify the adhesion of single zebrafish primary mesendodermal progenitors using atomic-force microscopy (AFM). We observed significant differences in detachment force and work between cultured mesendodermal progenitors from wild-type embryos and from slb/wnt11 mutant embryos, which carry a loss-of-function mutation in the wnt11 gene, when tested on fibronectin-coated substrates. These differences were probably due to reduced adhesion to the fibronectin substrate as neither the overall cell morphology nor the cell elasticity grossly differed between wild-type and mutant cells. Furthermore, in the presence of inhibitors of fibronectin-integrin binding, such as RGD peptides, the adhesion force and work were strongly decreased, indicating that integrins are involved in the binding of mesendodermal progenitors in our assay. These findings demonstrate that AFM can be used to quantitatively determine the substrate-adhesion of cultured primary gastrulating cells and provide insight into the role of Wnt11 signalling in modulating cell adhesion at the single cell scale.

  18. Histatin 1 Enhances Cell Adhesion to Titanium in an Implant Integration Model.

    Science.gov (United States)

    van Dijk, I A; Beker, A F; Jellema, W; Nazmi, K; Wu, G; Wismeijer, D; Krawczyk, P M; Bolscher, J G M; Veerman, E C I; Stap, J

    2017-04-01

    Cellular adhesion is essential for successful integration of dental implants. Rapid soft tissue integration is important to create a seal around the implant and prevent infections, which commonly cause implant failure and can result in bone loss. In addition, soft tissue management is important to obtain good dental aesthetics. We previously demonstrated that the salivary peptide histatin 1 (Hst1) causes a more than 2-fold increase in the ability of human adherent cells to attach and spread on a glass surface. Cells treated with Hst1 attached more rapidly and firmly to the substrate and to each other. In the current study, we examine the potential application of Hst1 for promotion of dental implant integration. Our results show that Hst1 enhances the attachment and spreading of soft tissue cell types (oral epithelial cells and fibroblasts) to titanium (Ti) and hydroxyapatite (HAP), biomaterials that have found wide applications as implant material in dentistry and orthopedics. For improved visualization of cell adhesion to Ti, we developed a novel technique that uses sputtering to deposit a thin, transparent layer of Ti onto glass slides. This approach allows detailed, high-resolution analysis of cell adherence to Ti in real time. Furthermore, our results suggest that Hst1 has no negative effects on cell survival. Given its natural occurrence in the oral cavity, Hst1 could be an attractive agent for clinical application. Importantly, even though Hst1 is specific for saliva of humans and higher primates, it stimulated the attachment and spreading of canine cells, paving the way for preclinical studies in canine models.

  19. SC1, an immunoglobulin-superfamily cell adhesion molecule, is involved in the brain metastatic activity of lung cancer cells

    Science.gov (United States)

    KUBOTA, YUKA; KIRIMURA, NAOKI; SHIBA, HATSUKI; ADACHI, KAZUHIDE; TSUKAMOTO, YASUHIRO

    2015-01-01

    SC1 is a cell adhesion molecule that belongs to the immunoglobulin superfamily; this molecule was initially purified from the chick embryonic nervous system and was reported to exhibit homophilic adhesion activity. SC1 is transiently expressed in various organs during development and has been identified in numerous neoplastic tissues, including lung cancer and colorectal carcinomas. The present study focused on the encephalic metastasis of lung cancer cells with respect to the potential function of SC1, as this molecule is known to be consistently expressed in the central nervous system as well as lung cancers. SC1 complementary DNA was introduced into A549 cells, a human lung cancer-derived cell line. The stable overexpression of the SC1 protein in A549 cells was demonstrated to enhance the self-aggregation of the cells. In addition, the SC1 transfectants enhanced the metastatic and invasive potential to the encephalic parenchyma following implantation into nude mice. In conclusion, the results of the present study demonstrated that cell adhesion due interactions between SC1 on brain tissue and SC1 on lung cancer cells was involved in the malignant aspects of lung cancer, including invasion and metastasis to the brain. PMID:26622821

  20. Orphan G protein-coupled receptor GPRC5A modulates integrin β1-mediated epithelial cell adhesion.

    Science.gov (United States)

    Bulanova, Daria R; Akimov, Yevhen A; Rokka, Anne; Laajala, Teemu D; Aittokallio, Tero; Kouvonen, Petri; Pellinen, Teijo; Kuznetsov, Sergey G

    2016-10-07

    G-Protein Coupled Receptor (GPCR), Class C, Group 5, Member A (GPRC5A) has been implicated in several malignancies. The underlying mechanisms, however, remain poorly understood. Using a panel of human cell lines, we demonstrate that CRISPR/Cas9-mediated knockout and RNAi-mediated depletion of GPRC5A impairs cell adhesion to integrin substrates: collagens I and IV, fibronectin, as well as to extracellular matrix proteins derived from the Engelbreth-Holm-Swarm (EHS) mouse sarcoma (Matrigel). Consistent with the phenotype, knock-out of GPRC5A correlated with a reduced integrin β1 (ITGB1) protein expression, impaired phosphorylation of the focal adhesion kinase (FAK), and lower activity of small GTPases RhoA and Rac1. Furthermore, we provide the first evidence for a direct interaction between GPRC5A and a receptor tyrosine kinase EphA2, an upstream regulator of FAK, although its contribution to the observed adhesion phenotype is unclear. Our findings reveal an unprecedented role for GPRC5A in regulation of the ITGB1-mediated cell adhesion and it's downstream signaling, thus indicating a potential novel role for GPRC5A in human epithelial cancers.

  1. Reduced Hepatic Carcinoembryonic Antigen-Related Cell Adhesion Molecule 1 Level in Obesity

    Science.gov (United States)

    Heinrich, Garrett; Muturi, Harrison T.; Rezaei, Khadijeh; Al-Share, Qusai Y.; DeAngelis, Anthony M.; Bowman, Thomas A.; Ghadieh, Hilda E.; Ghanem, Simona S.; Zhang, Deqiang; Garofalo, Robert S.; Yin, Lei; Najjar, Sonia M.

    2017-01-01

    Impairment of insulin clearance is being increasingly recognized as a critical step in the development of insulin resistance and metabolic disease. The carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) promotes insulin clearance. Null deletion or liver-specific inactivation of Ceacam1 in mice causes a defect in insulin clearance, insulin resistance, steatohepatitis, and visceral obesity. Immunohistological analysis revealed reduction of hepatic CEACAM1 in obese subjects with fatty liver disease. Thus, we aimed to determine whether this occurs at the hepatocyte level in response to systemic extrahepatic factors and whether this holds across species. Northern and Western blot analyses demonstrate that CEACAM1 mRNA and protein levels are reduced in liver tissues of obese individuals compared to their lean age-matched counterparts. Furthermore, Western analysis reveals a comparable reduction of CEACAM1 protein in primary hepatocytes derived from the same obese subjects. Similar to humans, Ceacam1 mRNA level, assessed by quantitative RT-PCR analysis, is significantly reduced in the livers of obese Zucker (fa/fa, ZDF) and Koletsky (f/f) rats relative to their age-matched lean counterparts. These studies demonstrate that the reduction of hepatic CEACAM1 in obesity occurs at the level of hepatocytes and identify the reduction of hepatic CEACAM1 as a common denominator of obesity across multiple species. PMID:28396653

  2. Cell Adhesion Molecule CD166 Drives Malignant Progression and Osteolytic Disease in Multiple Myeloma.

    Science.gov (United States)

    Xu, Linlin; Mohammad, Khalid S; Wu, Hao; Crean, Colin; Poteat, Bradley; Cheng, Yinghua; Cardoso, Angelo A; Machal, Christophe; Hanenberg, Helmut; Abonour, Rafat; Kacena, Melissa A; Chirgwin, John; Suvannasankha, Attaya; Srour, Edward F

    2016-12-01

    Multiple myeloma is incurable once osteolytic lesions have seeded at skeletal sites, but factors mediating this deadly pathogenic advance remain poorly understood. Here, we report evidence of a major role for the cell adhesion molecule CD166, which we discovered to be highly expressed in multiple myeloma cell lines and primary bone marrow cells from patients. CD166(+) multiple myeloma cells homed more efficiently than CD166(-) cells to the bone marrow of engrafted immunodeficient NSG mice. CD166 silencing in multiple myeloma cells enabled longer survival, a smaller tumor burden, and less osteolytic lesions, as compared with mice bearing control cells. CD166 deficiency in multiple myeloma cell lines or CD138(+) bone marrow cells from multiple myeloma patients compromised their ability to induce bone resorption in an ex vivo organ culture system. Furthermore, CD166 deficiency in multiple myeloma cells also reduced the formation of osteolytic disease in vivo after intratibial engraftment. Mechanistic investigation revealed that CD166 expression in multiple myeloma cells inhibited osteoblastogenesis of bone marrow-derived osteoblast progenitors by suppressing Runx2 gene expression. Conversely, CD166 expression in multiple myeloma cells promoted osteoclastogenesis by activating TRAF6-dependent signaling pathways in osteoclast progenitors. Overall, our results define CD166 as a pivotal director in multiple myeloma cell homing to the bone marrow and multiple myeloma progression, rationalizing its further study as a candidate therapeutic target for multiple myeloma treatment. Cancer Res; 76(23); 6901-10. ©2016 AACR. ©2016 American Association for Cancer Research.

  3. PERP regulates enamel formation via effects on cell-cell adhesion and gene expression.

    Science.gov (United States)

    Jheon, Andrew H; Mostowfi, Pasha; Snead, Malcolm L; Ihrie, Rebecca A; Sone, Eli; Pramparo, Tiziano; Attardi, Laura D; Klein, Ophir D

    2011-03-01

    Little is known about the role of cell-cell adhesion in the development of mineralized tissues. Here we report that PERP, a tetraspan membrane protein essential for epithelial integrity, regulates enamel formation. PERP is necessary for proper cell attachment and gene expression during tooth development, and its expression is controlled by P63, a master regulator of stratified epithelial development. During enamel formation, PERP is localized to the interface between the enamel-producing ameloblasts and the stratum intermedium (SI), a layer of cells subjacent to the ameloblasts. Perp-null mice display dramatic enamel defects, which are caused, in part, by the detachment of ameloblasts from the SI. Microarray analysis comparing gene expression in teeth of wild-type and Perp-null mice identified several differentially expressed genes during enamel formation. Analysis of these genes in ameloblast-derived LS8 cells upon knockdown of PERP confirmed the role for PERP in the regulation of gene expression. Together, our data show that PERP is necessary for the integrity of the ameloblast-SI interface and that a lack of Perp causes downregulation of genes that are required for proper enamel formation.

  4. Cell adhesive ability of a biological foam ceramic with surface modification

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Yong; Li Xiaoyu; Feng Fan; Lin Yunfeng [West China Hospital of Stomatology, Sichuan University, Chengdu 610041 (China); Liao Yunmao [State Key Laboratory of Oral Diseases, Chengdu 610044 (China); Tian, Weidong [State Key Laboratory of Oral Diseases, Chengdu 610044 (China)], E-mail: drtwd@sina.com; Liu Lei [West China Hospital of Stomatology, Sichuan University, Chengdu 610041 (China)], E-mail: drliulei@163.com

    2008-11-15

    Biological foam ceramic is a promising material for tissue engineering scaffold because of its biocompatibility, biodegradation and adequate pores measured from micrometer to nanometers. The aim of this study was to evaluate the adhesion and proliferation of adipose-derived stromal cells (ADSCs) on the biological foam ceramic coated with fibronectin. ADSCs were harvested from SD rats and passaged three times prior to seeding onto biological foam surface modified with fibronectin (50 {mu}g/ml). Scaffold without surface modification served as control. To characterize cellular attachment, cells were incubated on the scaffold for 1 h and 3 h and then the cells attached onto the scaffold were counted. The difference of proliferation was appraised using MTT assay at day 1, 3, 5 and 7 before the cells reached confluence. After 7 days of culture, scanning electron microscope (SEM) was chosen to assess cell morphology and attachment of ADSCs on the biological foam ceramic. Attachment of ADSCs on the biological foam ceramic surface modified with fibronectin at 1 h or 3 h was substantially greater than that in control. MTT assay revealed that ADSCs proliferation tendency of the experimental group was nearly parallel to that of control. SEM view showed that ADSCs in the experimental groups connected more tightly and excreted more collagen than that in control. The coating of fibronectin could improve the cell adhesive ability of biological foam ceramics without evident effect on proliferation.

  5. Surface modification with fibronectin or collagen to improve the cell adhesion

    Energy Technology Data Exchange (ETDEWEB)

    Li Xiaoyu [West China Hospital of Stomatology, Sichuan University, Chengdu 610041 (China); Yao Jinfeng [State Key Laboratory of Oral Diseases, Chengdu 610044 (China); Yang Xiaojuan [West China Hospital of Stomatology, Sichuan University, Chengdu 610041 (China); Tian Weidong [State Key Laboratory of Oral Diseases, Chengdu 610044 (China)], E-mail: drtwd@sina.com; Liu Lei [West China Hospital of Stomatology, Sichuan University, Chengdu 610041 (China)], E-mail: drliulei@163.com

    2008-11-15

    Objective: The surface of biomaterials plays a critical role in determining bioactivity. The aim of this study was to evaluate the cell adhesion and proliferation of ADSCs on the surface of biomaterial which is modified with fibronectin or collagen. Materials and methods: Adipose-derived stromal cells (ADSCs) were obtained from SD rats, expanded in culture, and seeded onto scaffold surface-modified with fibronectin or collagen. To characterize cellular attachment, cells were incubated on scaffold for 1 and 2 h and then counted the cells attached onto the scaffold. The MTT assay was chosen to evaluate the proliferation at days 1, 4, 7 and 14. After 7 d of culture, scanning electron microscope was chosen to observe cell morphology and attachment of ADSCs on the scaffolds. Results: Attachment at 1 and 2 h of cells on scaffold modified with fibronectin was significantly greater than in control, but not with collagen. The MTT assay revealed that ADSCs proliferation tendency was nearly parallel to that in control. The scanning electron microscope (SEM) showed that ADSCs in experiment expanded thoroughly and excreted much extracellular materials. Conclusions: Surface modification with fibronectin or collagen can enhance the attachment of cultured ADSCs on the scaffold, but it had not evident effect to proliferation.

  6. Enhanced Neural Cell Adhesion and Neurite Outgrowth on Graphene-Based Biomimetic Substrates

    Directory of Open Access Journals (Sweden)

    Suck Won Hong

    2014-01-01

    Full Text Available Neural cell adhesion and neurite outgrowth were examined on graphene-based biomimetic substrates. The biocompatibility of carbon nanomaterials such as graphene and carbon nanotubes (CNTs, that is, single-walled and multiwalled CNTs, against pheochromocytoma-derived PC-12 neural cells was also evaluated by quantifying metabolic activity (with WST-8 assay, intracellular oxidative stress (with ROS assay, and membrane integrity (with LDH assay. Graphene films were grown by using chemical vapor deposition and were then coated onto glass coverslips by using the scooping method. Graphene sheets were patterned on SiO2/Si substrates by using photolithography and were then covered with serum for a neural cell culture. Both types of CNTs induced significant dose-dependent decreases in the viability of PC-12 cells, whereas graphene exerted adverse effects on the neural cells just at over 62.5 ppm. This result implies that graphene and CNTs, even though they were the same carbon-based nanomaterials, show differential influences on neural cells. Furthermore, graphene-coated or graphene-patterned substrates were shown to substantially enhance the adhesion and neurite outgrowth of PC-12 cells. These results suggest that graphene-based substrates as biomimetic cues have good biocompatibility as well as a unique surface property that can enhance the neural cells, which would open up enormous opportunities in neural regeneration and nanomedicine.

  7. Enhanced neural cell adhesion and neurite outgrowth on graphene-based biomimetic substrates.

    Science.gov (United States)

    Hong, Suck Won; Lee, Jong Ho; Kang, Seok Hee; Hwang, Eun Young; Hwang, Yu-Shik; Lee, Mi Hee; Han, Dong-Wook; Park, Jong-Chul

    2014-01-01

    Neural cell adhesion and neurite outgrowth were examined on graphene-based biomimetic substrates. The biocompatibility of carbon nanomaterials such as graphene and carbon nanotubes (CNTs), that is, single-walled and multiwalled CNTs, against pheochromocytoma-derived PC-12 neural cells was also evaluated by quantifying metabolic activity (with WST-8 assay), intracellular oxidative stress (with ROS assay), and membrane integrity (with LDH assay). Graphene films were grown by using chemical vapor deposition and were then coated onto glass coverslips by using the scooping method. Graphene sheets were patterned on SiO2/Si substrates by using photolithography and were then covered with serum for a neural cell culture. Both types of CNTs induced significant dose-dependent decreases in the viability of PC-12 cells, whereas graphene exerted adverse effects on the neural cells just at over 62.5 ppm. This result implies that graphene and CNTs, even though they were the same carbon-based nanomaterials, show differential influences on neural cells. Furthermore, graphene-coated or graphene-patterned substrates were shown to substantially enhance the adhesion and neurite outgrowth of PC-12 cells. These results suggest that graphene-based substrates as biomimetic cues have good biocompatibility as well as a unique surface property that can enhance the neural cells, which would open up enormous opportunities in neural regeneration and nanomedicine.

  8. Immunization with a Neural-Derived Peptide Protects the Spinal Cord from Apoptosis after Traumatic Injury

    Directory of Open Access Journals (Sweden)

    Roxana Rodríguez-Barrera

    2013-01-01

    Full Text Available Apoptosis is one of the most destructive mechanisms that develop after spinal cord (SC injury. Immunization with neural-derived peptides (INDPs such as A91 has shown to reduce the deleterious proinflammatory response and the amount of harmful compounds produced after SC injury. With the notion that the aforementioned elements are apoptotic inducers, we hypothesized that INDPs would reduce apoptosis after SC injury. In order to test this assumption, adult rats were subjected to SC contusion and immunized either with A91 or phosphate buffered saline (PBS; control group. Seven days after injury, animals were euthanized to evaluate the number of apoptotic cells at the injury site. Apoptosis was evaluated using DAPI and TUNEL techniques; caspase-3 activity was also evaluated. To further elucidate the mechanisms through which A91 exerts this antiapoptotic effects we quantified tumor necrosis factor-alpha (TNF-α. To also demonstrate that the decrease in apoptotic cells correlated with a functional improvement, locomotor recovery was evaluated. Immunization with A91 significantly reduced the number of apoptotic cells and decreased caspase-3 activity and TNF-α concentration. Immunization with A91 also improved the functional recovery of injured rats. The present study shows the beneficial effect of INDPs on preventing apoptosis and provides more evidence on the neuroprotective mechanisms exerted by this strategy.

  9. Nonerythropoietic Erythropoietin-Derived Peptide Suppresses Adipogenesis, Inflammation, Obesity and Insulin Resistance

    Science.gov (United States)

    Liu, Yuqi; Luo, Bangwei; Shi, Rongchen; Wang, Jinsong; Liu, Zongwei; Liu, Wei; Wang, Shufeng; Zhang, Zhiren

    2015-01-01

    Erythropoietin (EPO) has been identified as being crucial for obesity modulation; however, its erythropoietic activity may limit its clinical application. EPO-derived Helix B-surface peptide (pHBSP) is nonerythrogenic but has been reported to retain other functions of EPO. The current study aimed to evaluate the effects and potential mechanisms of pHBSP in obesity modulation. We found that pHBSP suppressed adipogenesis, adipokine expression and peroxisome proliferator-activated receptor γ (PPARγ) levels during 3T3-L1 preadipocyte maturation through the EPO receptor (EPOR). In addition, also through EPOR, pHBSP attenuated macrophage inflammatory activation and promoted PPARγ expression. Furthermore, PPARγ deficiency partly ablated the anti-inflammatory activity of pHBSP in macrophages. Correspondingly, pHBSP administration to high-fat diet (HFD)-fed mice significantly improved obesity, insulin resistance (IR) and adipose tissue inflammation without stimulating hematopoiesis. Therefore, pHBSP can significantly protect against obesity and IR partly by inhibiting adipogenesis and inflammation. These findings have therapeutic implications for metabolic disorders, such as obesity and diabetes. PMID:26459940

  10. Antimicrobial Activity of a Halocidin-Derived Peptide Resistant to Attacks by Proteases ▿

    Science.gov (United States)

    Shin, Yong Pyo; Park, Ho Jin; Shin, Seo Hwa; Lee, Young Shin; Park, Seungmi; Jo, Sungho; Lee, Yong Ho; Lee, In Hee

    2010-01-01

    Cationic antimicrobial peptides (AMPs) have attracted a great deal of interest as a promising candidate for a novel class of antibiotics that might effectively treat recalcitrant infections caused by a variety of microbes that are resistant to currently available drugs. However, the AMPs are inherently limited in that they are inevitably susceptible to attacks by proteases generated by human and pathogenic microbes; this vulnerability severely hinders their pharmaceutical use in human therapeutic protocols. In this study, we report that a halocidin-derived AMP, designated HG1, was found to be resistant to proteolytic degradation. As a result of its unique structural features, HG1 proved capable of preserving its antimicrobial activity after incubation with trypsin, chymotrypsin, and human matrix metalloprotease 7 (MMP-7). Additionally, HG1 was observed to exhibit profound antimicrobial activity in the presence of fluid from human skin wounds or proteins extracted from the culture supernatants of Staphylococcus aureus and Pseudomonas aeruginosa. Greater understanding of the structural motifs of HG1 required for its protease resistance might provide feasible ways to solve the problems intrinsic to the development of an AMP-based antibiotic. PMID:20385874

  11. Erythropoietin-derived nonerythropoietic peptide ameliorates experimental autoimmune neuritis by inflammation suppression and tissue protection.

    Directory of Open Access Journals (Sweden)

    Yuqi Liu

    Full Text Available Experimental autoimmune neuritis (EAN is an autoantigen-specific T-cell-mediated disease model for human demyelinating inflammatory disease of the peripheral nervous system. Erythropoietin (EPO has been known to promote EAN recovery but its haematopoiesis stimulating effects may limit its clinic application. Here we investigated the effects and potential mechanisms of an EPO-derived nonerythropoietic peptide, ARA 290, in EAN. Exogenous ARA 290 intervention greatly improved EAN recovery, improved nerve regeneration and remyelination, and suppressed nerve inflammation. Furthermore, haematopoiesis was not induced by ARA 290 during EAN treatment. ARA 290 intervention suppressed lymphocyte proliferation and altered helper T cell differentiation by inducing increase of Foxp3+/CD4+ regulatory T cells and IL-4+/CD4+ Th2 cells and decrease of IFN-γ+/CD4+ Th1 cells in EAN. In addition, ARA 290 inhibited inflammatory macrophage activation and promoted its phagocytic activity. In vitro, ARA 290 was shown to promote Schwann cell proliferation and inhibit its inflammatory activation. In summary, our data demonstrated that ARA 290 could effectively suppress EAN by attenuating inflammation and exerting direct cell protection, indicating that ARA 290 could be a potent candidate for treatment of autoimmune neuropathies.

  12. Design and synthesis of tryptophan containing dipeptide derivatives as formyl peptide receptor 1 antagonist.

    Science.gov (United States)

    Hwang, Tsong-Long; Hung, Chih-Hao; Hsu, Ching-Yun; Huang, Yin-Ting; Tsai, Yu-Chi; Hsieh, Pei-Wen

    2013-06-14

    Our previous studies identified an Fmoc-(S,R)-tryptophan-containing dipeptide derivative, 1, which selectively inhibited neutrophil elastase release induced by formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP) in human neutrophils. In an attempt to improve pharmacological activity, a series of tryptophan-containing dipeptides were synthesized and their pharmacological activities were investigated in human neutrophils. Of these, five compounds 3, 6, 19a, 24a, and 24b exhibited potent and dual inhibitory effects on FMLP-induced superoxide anion (O2˙(-)) generation and neutrophil elastase release in neutrophils with IC50 values of 0.23/0.60, 1.88/2.47, 1.87/3.60, 0.12/0.37, and 1.32/1.03 μM, respectively. Further studies indicated that inhibition of superoxide production in human neutrophils by these dipeptides was associated with the selective inhibition of formyl peptide receptor 1 (FPR1). Furthermore, the results of structure-activity relationship studies concluded that the fragment N-benzoyl-Trp-Phe-OMe (3) was most suitable as a core structure for interaction with FPR1, and may be approved as a lead for the development of new drugs in the treatment of neutrophilic inflammatory diseases. As some of the synthesized compounds exhibited separable conformational isomers, and showed diverse bioactivities, the conformation analysis of these compounds is also discussed herein.

  13. Pancreatic Neuroendocrine Tumors in Mice Deficient in Proglucagon-Derived Peptides.

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    Yuko Takano

    Full Text Available Animal models with defective glucagon action show hyperplasia of islet α-cells, however, the regulatory mechanisms underlying the proliferation of islet endocrine cells remain largely to be elucidated. The Gcggfp/gfp mice, which are homozygous for glucagon/green fluorescent protein knock-in allele (GCGKO, lack all proglucagon-derived peptides including glucagon and GLP-1. The present study was aimed to characterize pancreatic neuroendocrine tumors (panNETs, which develop in the GCGKO mice. At 15 months of age, macroscopic GFP-positive tumors were identified in the pancreas of all the GCGKO mice, but not in that of the control heterozygous mice. The tumor manifested several features that were consistent with pancreatic neuroendocrine tumors (panNETs, such as organoid structures with trabecular and cribriform patterns, and the expression of chromogranin A and synaptophysin. Dissemination of GFP-positive cells was observed in the liver and lungs in 100% and 95%, respectively, of 15-month-old GCGKO mice. To elucidate the regulatory mechanism for tumor growth, PanNET grafts were transplanted into subrenal capsules in GCGKO and control mice. Ki-67 positive cells were identified in panNET grafts transplanted to GCGKO mice 1 month after transplantation, but not in those to control mice. These results suggest that humoral factors or conditions specific to GCGKO mice, are involved in the proliferation of panNETs. Taken together, GCGKO mice are novel animal model for studying the development, pathogenesis, and metastasis panNETs.

  14. Chebulin: Terminalia chebula Retz. fruit-derived peptide with angiotensin-I-converting enzyme inhibitory activity.

    Science.gov (United States)

    Sornwatana, Thakorn; Bangphoomi, Kunan; Roytrakul, Sittiruk; Wetprasit, Nuanchawee; Choowongkomon, Kiattawee; Ratanapo, Sunanta

    2015-01-01

    Angiotensin-I-converting enzyme (ACE) plays an important role in blood pressure regulation. In this study, an ACE-hexapeptide inhibitor (Asp-Glu-Asn-Ser-Lys-Phe) designated as chebulin was produced from the fruit protein of Terminalia chebula Retz. by pepsin digestion, ultrafiltrated through a 3 KDa cut-off membrane, a reverse-phase high-performance liquid chromatography, and nano-liquid chromatography tandem mass spectrometry analysis. Chebulin was found to inhibit ACE in a noncompetitive manner, as supported by the structural model. It bounds to ACE by the hydrogen bond, hydrophobic and ionic interactions via the interactions of C-terminal Phe (Phe-6), and N-terminal residues (Asp-1 and Glu-2) with the amino acid residues on noncatalytic sites of the ACE. The results showed that chebulin derived from fruits of T. chebula Retz. is a potential ACE-peptide inhibitor that could be used as a functional food additive for the prevention of hypertension and as an alternative to ACE inhibitor drug.

  15. Artificial Neural Network for Production of Antioxidant Peptides Derived from Bighead Carp Muscles with Alcalase

    Directory of Open Access Journals (Sweden)

    Lin Li

    2006-01-01

    Full Text Available Controlled enzymatic modification proteins are currently being used as good sources of bioactive protein ingredients, and hydrolysates derived from bighead carp muscles may serve as antioxidants through the control of the processing-related parameters. The antioxidant ability was evaluated with regard to the scavenging effect on free radical DPPH·, OH· and O2 ·–. Due to the robustness, fault tolerance, high computational speed and self--learning ability, artificial neural network (ANN can be employed to build a predictive model for hydrolysis and optimize the hydrolysis variables: pH, temperature, hydrolysis time, muscle/water ratio and enzyme/substrate ratio (E/S for the production of antioxidant peptides. Optimum conditions to achieve the maximum antioxidant ability were obtained. The hydrolysates, which scavenged most effectively the DPPH·, OH· and O2 ·–, were hydrolyzed for 4.8 h with an activity of alcalase of 4.8 AU/kg, for 6 h with 3.84 AU/kg and for 4.3 h with 4.8 AU/kg, at pH=7.5 and 60 °C. Their respective muscle/water ratio was 1:1.9, 1:1.4 and 1:1. The present study confirmed that ANN could be used to simulate the hydrolysis process and predict hydrolysis conditions under which the hydrolysates could show the most effective scavenging ability on DPPH·, OH· and O2 ·–.

  16. Activity and Mechanism of Antimicrobial Peptide-Mimetic Amphiphilic Polymethacrylate Derivatives

    Directory of Open Access Journals (Sweden)

    Kenichi Kuroda

    2011-09-01

    Full Text Available Cationic amphiphilic polymethacrylate derivatives (PMAs have shown potential as a novel class of synthetic antimicrobials. A panel of PMAs with varied ratios of hydrophobic and cationic side chains were synthesized and tested for antimicrobial activity and mechanism of action. The PMAs are shown to be active against a panel of pathogenic bacteria, including a drug-resistant Staphylococcus aureus, compared to the natural antimicrobial peptide magainin which did not display any activity against the same strain. The selected PMAs with 47–63% of methyl groups in the side chains showed minimum inhibitory concentrations of ≤2–31 µg/mL, but cause only minimal harm to human red blood cells. The PMAs also exhibit rapid bactericidal kinetics. Culturing Escherichia coli in the presence of the PMAs did not exhibit any potential to develop resistance against the PMAs. The antibacterial activities of PMAs against E. coli and S. aureus were slightly reduced in the presence of physiological salts. The activity of PMAs showed bactericidal effects against E. coli and S. aureus in both exponential and stationary growth phases. These results demonstrate that PMAs are a new antimicrobial platform with no observed development of resistance in bacteria. In addition, the PMAs permeabilized the E. coli outer membrane at polymer concentrations lower than their MIC values, but they did not show any effect on the bacterial inner membrane. This indicates that mechanisms other than membrane permeabilization may be the primary factors determining their antimicrobial activity.

  17. The ADNP derived peptide, NAP modulates the tubulin pool: implication for neurotrophic and neuroprotective activities.

    Directory of Open Access Journals (Sweden)

    Saar Oz

    Full Text Available Microtubules (MTs, key cytoskeletal elements in living cells, are critical for axonal transport, synaptic transmission, and maintenance of neuronal morphology. NAP (NAPVSIPQ is a neuroprotective peptide derived from the essential activity-dependent neuroprotective protein (ADNP. In Alzheimer's disease models, NAP protects against tauopathy and cognitive decline. Here, we show that NAP treatment significantly affected the alpha tubulin tyrosination cycle in the neuronal differentiation model, rat pheochromocytoma (PC12 and in rat cortical astrocytes. The effect on tubulin tyrosination/detyrosination was coupled to increased MT network area (measured in PC12 cells, which is directly related to neurite outgrowth. Tubulin beta3, a marker for neurite outgrowth/neuronal differentiation significantly increased after NAP treatment. In rat cortical neurons, NAP doubled the area of dynamic MT invasion (Tyr-tubulin into the neuronal growth cone periphery. NAP was previously shown to protect against zinc-induced MT/neurite destruction and neuronal death, here, in PC12 cells, NAP treatment reversed zinc-decreased tau-tubulin-MT interaction and protected against death. NAP effects on the MT pool, coupled with increased tau engagement on compromised MTs imply an important role in neuronal plasticity, protecting against free tau accumulation leading to tauopathy. With tauopathy representing a major pathological hallmark in Alzheimer's disease and related disorders, the current findings provide a mechanistic basis for further development. NAP (davunetide is in phase 2/3 clinical trial in progressive supranuclear palsy, a disease presenting MT deficiency and tau pathology.

  18. Antiosteoporotic effect of orally administered yolk-derived peptides on bone mass in women.

    Science.gov (United States)

    Abdou, Adham M; Watabe, Kazuya; Yamane, Tetsuro; Isono, Tadayuki; Okamura, Yoshitaka; Kawahito, Seiji; Takeshima, Kazuhito; Masuda, Kazuyuki; Kim, Mujo

    2014-05-01

    The main objective of this study was to verify the effect of oral intake of a yolk-derived peptide preparation (HYP) obtained by enzymatic hydrolysis of yolk water-soluble protein on bone markers and bone density in 65 perimenopausal women with an average age of 47.6 ± 5.2 years. Subjects were divided into three groups, and then enrolled in a 6-month, randomized, double-blind clinical trial. Bone formation and resorption markers were measured at 0, 3, and 6 months, while bone mineral density (BMD) in the lumbar spines was measured at 0 and 6 months. Although the bone formation marker levels showed the similarity changes among the groups, bone resorption markers in the test HYP group were significantly decreased after 3 and 6 months in comparison to other groups (P < 0.05). After 6 months, BMD in the test HYP group maintained at healthy numerical values whereas BMD values were decreased in other groups. Hence HYP would be an antiosteoporotic agent originated from natural food to maintain bone health, especially for women.

  19. Synthetic Long Peptide Derived from Mycobacterium tuberculosis Latency Antigen Rv1733c Protects against Tuberculosis.

    Science.gov (United States)

    Coppola, Mariateresa; van den Eeden, Susan J F; Wilson, Louis; Franken, Kees L M C; Ottenhoff, Tom H M; Geluk, Annemieke

    2015-09-01

    Responsible for 9 million new cases of active disease and nearly 2 million deaths each year, tuberculosis (TB) remains a global health threat of overwhelming dimensions. Mycobacterium bovis BCG, the only licensed vaccine available, fails to confer lifelong protection and to prevent reactivation of latent infection. Although 15 new vaccine candidates are now in clinical trials, an effective vaccine against TB remains elusive, and new strategies for vaccination are vital. BCG vaccination fails to induce immunity against Mycobacterium tuberculosis latency antigens. Synthetic long peptides (SLPs) combined with adjuvants have been studied mostly for therapeutic cancer vaccines, yet not for TB, and proved to induce efficient antitumor immunity. This study investigated an SLP derived from Rv1733c, a major M. tuberculosis latency antigen which is highly expressed by "dormant" M. tuberculosis and well recognized by T cells from latently M. tuberculosis-infected individuals. In order to assess its in vivo immunogenicity and protective capacity, Rv1733c SLP in CpG was administered to HLA-DR3 transgenic mice. Immunization with Rv1733c SLP elicited gamma interferon-positive/tumor necrosis factor-positive (IFN-γ(+)/TNF(+)) and IFN-γ(+) CD4(+) T cells and Rv1733c-specific antibodies and led to a significant reduction in the bacterial load in the lungs of M. tuberculosis-challenged mice. This was observed both in a pre- and in a post-M. tuberculosis challenge setting. Moreover, Rv1733c SLP immunization significantly boosted the protective efficacy of BCG, demonstrating the potential of M. tuberculosis latency antigens to improve BCG efficacy. These data suggest a promising role for M. tuberculosis latency antigen Rv1733c-derived SLPs as a novel TB vaccine approach, both in a prophylactic and in a postinfection setting.

  20. Emerging roles for the amyloid precursor protein and derived peptides in the regulation of cellular and systemic metabolism.

    Science.gov (United States)

    Czeczor, Juliane K; McGee, Sean L

    2017-03-28

    The amyloid precursor protein (APP) is a transmembrane protein that can be cleaved by proteases through two different pathways to yield a number of small peptides, each with distinct physiological properties and functions. It has been extensively studied in the context of Alzheimer's disease, with the APP-derived amyloid beta (Aβ) peptide being a major constituent of the amyloid plaques observed in this disease. It has been known for some time that APP can regulate neuronal metabolism, however this review will examine evidence that APP and its peptides can also regulate key metabolic processes such as insulin action, lipid synthesis and storage and mitochondrial function in peripheral tissues. This review will present a hypothesis that amyloidogenic processing of APP in peripheral tissues plays a key role in the response to nutrient excess and that this could contribute to the pathogenesis of metabolic diseases such as obesity and type 2 diabetes (T2D). This article is protected by copyright. All rights reserved.

  1. Multiplexed Quantification of Proglucagon-Derived Peptides by Immunoaffinity Enrichment and Tandem Mass Spectrometry after a Meal Tolerance Test

    DEFF Research Database (Denmark)

    Lee, Anita Y H; Chappell, Derek L; Bak, Monika J;

    2016-01-01

    BACKGROUND: Proglucagon-derived peptides (PGDPs), which include glucagon-like peptide (GLP)-1, glucagon, and oxyntomodulin, are key regulators of glucose homeostasis and satiety. These peptide hormones are typically measured with immuno-based assays (e.g., ELISA, RIA), which often suffer from...... issues of selectivity. METHODS: We developed a multiplexed assay for measuring PGDPs including GLP-1 (7-36) amide, GLP-1 (9-36) amide, glucagon, and oxyntomodulin by mass spectrometry and used this assay to examine the effect of a meal tolerance test on circulating concentrations of these hormones....... Participants fasted overnight and were either given a meal (n = 8) or continued to fast (n = 4), with multiple blood collections over the course of 3 h. Plasma samples were analyzed by microflow immunoaffinity (IA)-LC-MS/MS with an isotope dilution strategy. RESULTS: Assay performance characteristics were...

  2. Structural and pharmacological characteristics of chimeric peptides derived from peptide E and beta-endorphin reveal the crucial role of the C-terminal YGGFL and YKKGE motifs in their analgesic properties.

    Science.gov (United States)

    Condamine, Eric; Courchay, Karine; Rego, Jean-Claude Do; Leprince, Jérôme; Mayer, Catherine; Davoust, Daniel; Costentin, Jean; Vaudry, Hubert

    2010-05-01

    Peptide E (a 25-amino acid peptide derived from proenkephalin A) and beta-endorphin (a 31-amino acid peptide derived from proopiomelanocortin) bind with high affinity to opioid receptors and share structural similarities but induce analgesic effects of very different intensity. Indeed, whereas they possess the same N-terminus Met-enkephalin message sequence linked to a helix by a flexible spacer and a C-terminal part in random coil conformation, in contrast with peptide E, beta-endorphin produces a profound analgesia. To determine the key structural elements explaining this very divergent opioid activity, we have compared the structural and pharmacological characteristics of several chimeric peptides derived from peptide E and beta-endorphin. Structures were obtained under the same experimental conditions using circular dichroism, computational estimation of helical content and/or nuclear magnetic resonance spectroscopy (NMR) and NMR-restrained molecular modeling. The hot-plate and writhing tests were used in mice to evaluate the antinociceptive effects of the peptides. Our results indicate that neither the length nor the physicochemical profile of the spacer plays a fundamental role in analgesia. On the other hand, while the functional importance of the helix cannot be excluded, the last 5 residues in the C-terminal part seem to be crucial for the expression or absence of the analgesic activity of these peptides. These data raise the question of the true function of peptides E in opioidergic systems.

  3. Technological options for the production of health-promoting proteins and peptides derived from milk and colostrum.

    Science.gov (United States)

    Korhonen, H; Pihlanto, A

    2007-01-01

    Milk proteins are known to exert a wide range of nutritional, functional and biological activities. Apart from being a balanced source of valuable amino acids, milk proteins contribute to the consistency and sensory properties of various dairy products. Furthermore, many milk proteins possess specific biological properties which make them potential ingredients of health-promoting foods. These properties are attributed to both native protein molecules and to physiologically active peptides encrypted in the protein molecules. Considerable progress has been made over the last twenty years in technologies aimed at separation, fractionation and isolation in a purified form of many interesting proteins occurring in bovine colostrum and milk. Industrial-scale methods have been developed for native whey proteins such as immunoglobulins, lactoferrin, lactoperoxidase, alpha-lactalbumin and beta-lactoglobulin. Their large-scale manufacture and commercial exploitation is still limited although validated research data about their physiological health benefits is rapidly accumulating. Promising product concepts and novel fields of use have emerged recently, and some of these molecules have already found commercial applications. The same applies to bioactive peptides derived from different milk proteins. Active peptides can be liberated during gastrointestinal digestion or milk fermentation with proteolytic enzymes. Such peptides may exert a number of physiological effects in vivo on the gastrointestinal, cardiovascular, endocrine, immune, nervous and other body systems. However, at present the industrial-scale production of such peptides is limited by a lack of suitable technologies. On the other hand, a number of bioactive peptides have been identified in fermented dairy products, and there are already a few commercial dairy products enriched with blood pressure-reducing milk protein peptides. There is a need to develop methods to optimise the activity of bioactive peptides in

  4. Identification of a Novel P190-Derived Breakpoint Peptide Suitable for Peptide Vaccine Therapeutic Approach in Ph+ Acute Lymphoblastic Leukemia Patients

    OpenAIRE

    Ippoliti, Micaela; Defina, Marzia; Gozzini, Antonella; Baratè, Claudia; Aprile, Lara; Pietrini, Alice; Gozzetti, Alessandro; Raspadori, Donatella; Lauria, Francesco; Bocchia, Monica

    2012-01-01

    Ph+ acute lymphoblastic leukemia (Ph+ ALL) is a high-risk acute leukemia with poor prognosis, in which the specific t(9;22)(q34;q11) translocation results in a chimeric bcr-abl (e1a2 breakpoint) and in a 190 KD protein (p190) with constitutive tyrosine kinase activity. The advent of first- and second-generation tyrosine kinase inhibitors (TKIs) improved the short-term outcome of Ph+ ALL patients not eligible for allo-SCT; yet disease recurrence is almost inevitable. Peptides derived from p190...

  5. Modeling keratinocyte wound healing dynamics: Cell-cell adhesion promotes sustained collective migration.

    Science.gov (United States)

    Nardini, John T; Chapnick, Douglas A; Liu, Xuedong; Bortz, David M

    2016-07-07

    The in vitro migration of keratinocyte cell sheets displays behavioral and biochemical similarities to the in vivo wound healing response of keratinocytes in animal model systems. In both cases, ligand-dependent Epidermal Growth Factor Receptor (EGFR) activation is sufficient to elicit collective cell migration into the wound. Previous mathematical modeling studies of in vitro wound healing assays assume that physical connections between cells have a hindering effect on cell migration, but biological literature suggests a more complicated story. By combining mathematical modeling and experimental observations of collectively migrating sheets of keratinocytes, we investigate the role of cell-cell adhesion during in vitro keratinocyte wound healing assays. We develop and compare two nonlinear diffusion models of the wound healing process in which cell-cell adhesion either hinders or promotes migration. Both models can accurately fit the leading edge propagation of cell sheets during wound healing when using a time-dependent rate of cell-cell adhesion strength. The model that assumes a positive role of cell-cell adhesion on migration, however, is robust to changes in the leading edge definition and yields a qualitatively accurate density profile. Using RNAi for the critical adherens junction protein, α-catenin, we demonstrate that cell sheets with wild type cell-cell adhesion expression maintain migration into the wound longer than cell sheets with decreased cell-cell adhesion expression, which fails to exhibit collective migration. Our modeling and experimental data thus suggest that cell-cell adhesion promotes sustained migration as cells pull neighboring cells into the wound during wound healing.

  6. Material- and feature-dependent effects on cell adhesion to micro injection moulded medical polymers.

    Science.gov (United States)

    Choi, Seong Ying; Habimana, Olivier; Flood, Peter; Reynaud, Emmanuel G; Rodriguez, Brian J; Zhang, Nan; Casey, Eoin; Gilchrist, Michael D

    2016-09-01

    Two polymers, polymethylmethacrylate (PMMA) and cyclic olefin copolymer (COC), containing a range of nano- to micron- roughness surfaces (Ra 0.01, 0.1, 0.4, 1.0, 2.0, 3.2 and 5.0μm) were fabricated using electrical discharge machining (EDM) and replicated using micro injection moulding (μIM). Polymer samples were characterized using optical profilometry, atomic force microscopy (AFM) and water surface contact angle. Cell adhesion tests were carried out using bacterial Pseudomonas fluorescens and mammalian Madin-Darby Canine Kidney (MDCK) cells to determine the effect of surface hydrophobicity, surface roughness and stiffness. It is found that there are features which gave insignificant differences (feature-dependent effect) in cell adhesion, albeit a significant difference in the physicochemical properties (material-dependent effect) of substrata. In bacterial cell adhesion, the strongest feature-dependence is found at Ra 0.4μm surfaces, with material-dependent effects strongest at Ra 0.01μm. Ra 0.1μm surfaces exhibited strongest feature-dependent effects and Ra 5.0μm has strongest material-dependent effects on mammalian cell adhesion. Bacterial cell adhesion is found to be favourable to hydrophobic surfaces (COC), with the lowest adhesion at Ra 0.4μm for both materials. Mammalian cell adhesion is lowest in Ra 0.1μm and highest in Ra 1.0μm, and generally favours hydrophilic surfaces (PMMA). These findings can be used as a basis for developing medical implants or microfluidic devices using micro injection moulding for diagnostic purposes, by tuning the cell adhesion on different areas containing different surface roughnesses on the diagnostic microfluidic devices or medical implants.

  7. Antibodies Directed against a Peptide Epitope of a Klebsiella pneumoniae-Derived Protein Are Present in Ankylosing Spondylitis

    Science.gov (United States)

    Tinazzi, Elisa; Moretta, Francesca; D’Angelo, Salvatore; Olivieri, Ignazio; Lunardi, Claudio

    2017-01-01

    Ankylosing spondylitis (AS) is a chronic inflammatory arthritis of unknown origin. Its autoimmune origin has been suggested but never proven. Several reports have implicated Klebsiella pneumoniae as a triggering or perpetuating factor in AS; however, its role in the disease pathogenesis remains debated. Moreover, despite extensive investigations, a biomarker for AS has not yet been identified. To clarify these issues, we screened a random peptide library with pooled IgGs obtained from 40 patients with AS. A peptide (AS peptide) selected from the library was recognized by serum IgGs from 170 of 200 (85%) patients with AS but not by serum specimens from 100 healthy controls. Interestingly, the AS peptide shows a sequence similarity with several molecules expressed at the fibrocartilaginous sites that are primarily involved in the AS inflammatory process. Moreover, the peptide is highly homologous to a Klebsiella pneumoniae dipeptidase (DPP) protein. The antibody affinity purified against the AS peptide recognizes the autoantigens and the DPP protein. Furthermore, serum IgG antibodies against the Klebsiella DPP121-145 peptide epitope were detected in 190 of 200 patients with AS (95%), 3 of 200 patients with rheumatoid arthritis (1.5%) and only 1 of 100 (1%) patients with psoriatic arthritis. Such reactivity was not detected in healthy control donors. Our results show that antibodies directed against an epitope of a Klebsiella pneumoniae-derived protein are present in nearly all patients with AS. In the absence of serological biomarkers for AS, such antibodies may represent a useful tool in the diagnosis of the disease. PMID:28135336

  8. Peptide p5 binds both heparinase-sensitive glycosaminoglycans and fibrils in patient-derived AL amyloid extracts

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Emily B.; Williams, Angela [Department of Medicine, University of Tennessee Graduate School of Medicine, 1924 Alcoa Highway, Knoxville, TN 37922 (United States); Heidel, Eric [Department of Surgery, University of Tennessee Graduate School of Medicine, 1924 Alcoa Highway, Knoxville, TN 37922 (United States); Macy, Sallie [Department of Medicine, University of Tennessee Graduate School of Medicine, 1924 Alcoa Highway, Knoxville, TN 37922 (United States); Kennel, Stephen J. [Department of Medicine, University of Tennessee Graduate School of Medicine, 1924 Alcoa Highway, Knoxville, TN 37922 (United States); Department of Radiology, University of Tennessee Graduate School of Medicine, 1924 Alcoa Highway, Knoxville, TN 37922 (United States); Wall, Jonathan S., E-mail: jwall@utmck.edu [Department of Medicine, University of Tennessee Graduate School of Medicine, 1924 Alcoa Highway, Knoxville, TN 37922 (United States); Department of Radiology, University of Tennessee Graduate School of Medicine, 1924 Alcoa Highway, Knoxville, TN 37922 (United States)

    2013-06-21

    Highlights: •Polybasic peptide p5 binds human light chain amyloid extracts. •The binding of p5 with amyloid involves both glycosaminoglycans and fibrils. •Heparinase treatment led to a correlation between p5 binding and fibril content. •p5 binding to AL amyloid requires electrostatic interactions. -- Abstract: In previously published work, we have described heparin-binding synthetic peptides that preferentially recognize amyloid deposits in a mouse model of reactive systemic (AA) amyloidosis and can be imaged by using positron and single photon emission tomographic imaging. We wanted to extend these findings to the most common form of visceral amyloidosis, namely light chain (AL); however, there are no robust experimental animal models of AL amyloidosis. To further define the binding of the lead peptide, p5, to AL amyloid, we characterized the reactivity in vitro of p5 with in situ and patient-derived AL amyloid extracts which contain both hypersulfated heparan sulfate proteoglycans as well as amyloid fibrils. Histochemical staining demonstrated that the peptide specifically localized with tissue-associated AL amyloid deposits. Although we anticipated that p5 would undergo electrostatic interactions with the amyloid-associated glycosaminoglycans expressing heparin-like side chains, no significant correlation between peptide binding and glycosaminoglycan content within amyloid extracts was observed. In contrast, following heparinase I treatment, although overall binding was reduced, a positive correlation between peptide binding and amyloid fibril content became evident. This interaction was further confirmed using synthetic light chain fibrils that contain no carbohydrates. These data suggest that p5 can bind to both the sulfated glycosaminoglycans and protein fibril components of AL amyloid. Understanding these complex electrostatic interactions will aid in the optimization of synthetic peptides for use as amyloid imaging agents and potentially as

  9. Administration of bovine casein-derived peptide prevents cognitive decline in Alzheimer disease model mice

    Science.gov (United States)

    Tsukuda, Kana; Yamada, Akio; Yamauchi, Koji; Abe, Fumiaki; Iwanami, Jun; Xiao, Jin-Zhong; Horiuchi, Masatsugu

    2017-01-01

    There is a growing interest in identifying natural food ingredients that may serve to prevent dementia such as that due to Alzheimer disease (AD). Peptides derived from food proteins have been demonstrated to have various physiological activities such as a hypotensive action. Recent findings have indicated possible associations of hypertension with AD progression, and suggest that angiotensin converting enzyme (ACE) inhibitors with potential to pass through the blood brain barrier (BBB) may reduce the risk of AD. In this study, we investigated the effect of milk peptide (CH-3) on cognitive function in AD model mice. CH-3 contains a tripeptide (methionine-lysine-proline, MKP) that has been found to have a strong ACE inhibitory effect and the potential to pass through the BBB. Adult male ddY mice were used in this study, and an animal model of AD was induced by intracerebroventricular (ICV) injection of Aβ1–42. CH-3 (250 mg/kg/day) or MKP (0.5 mg/kg/day) was orally administered every day starting 2 days before ICV injection. At 3 weeks after ICV injection, cognitive function was evaluated by the Morris water maze test. Brain samples were obtained after behavioral testing, and expression of inflammatory cytokines and NADPH oxidase subunits was measured by real-time quantitative RT-PCR. ICV injection of Aβ1–42 significantly impaired cognitive function compared with that in PBS-injected mice. Daily administration of CH-3 markedly attenuated this Aβ1-42-induced cognitive decline. Aβ1–42 injection significantly enhanced the expression of tumor necrosis factor-α (TNF-α), inducible nitric oxide synthase (iNOS) and p22phox in the mouse hippocampus compared with PBS injection, and showed a tendency to increase the expression of monocyte chemoattractant protein-1 (MCP-1), p47phox and gp91phox, whereas CH-3 treatment markedly reduced Aβ1-42-induced TNF-α, MCP-1, iNOS, p47phox and gp91phox expression. Finally, administration of MKP also attenuated Aβ1-42-induced

  10. Isolation and characterisation of a novel antibacterial peptide from a native swine intestinal tract-derived bacterium.

    Science.gov (United States)

    Xin, Haiyun; Ji, Shengyue; Peng, Jiayin; Han, Peng; An, Xiaopeng; Wang, Shan; Cao, Binyun

    2017-02-27

    Antimicrobial peptides (AMPs) are highly associated with antipathogenic activity, without generating drug resistance in targeted bacteria. In this study, the existence of AMPs in the Tibetan swine, a China-native, cold-resistant and seldom-sick breed of pig, was investigated. A peptide secreted by a Tibetan swine intestinal tract-derived Bacillus strain was isolated using reversed-phase chromatography (RPC), ultrafiltration and reversed-phase high-performance liquid chromatography (RP-HPLC). The peptide was identified by mass spectrometry and was characterised for activity against Escherichia coli and Staphylococcus aureus. The 16-amino acid peptide (ASVVNKLTGGVAGLLK), named TP, had a molecular mass of 1568.919 Da and exhibited inhibitory activity against Gram-positive and Gram-negative bacteria [minimum inhibitory concentrations (MICs) of 2.5-5 µM and 10-20 µM for E. coli and S. aureus, respectively] as well as human MKN-45 and NB4 tumour cell lines [50% inhibitory concentration (IC50) = 4.686 µM and 11.479 µM, respectively]. TP also exhibited weak haemolytic activity. Furthermore, TP enhanced cell membrane permeability and K(+) outflow, bound with E. coli genomic DNA in vitro and inhibited E. coli growth. Thus, TP represents a strong candidate as an antibacterial peptide.

  11. Multi-species sequence comparison reveals conservation of ghrelin gene-derived splice variants encoding a truncated ghrelin peptide.

    Science.gov (United States)

    Seim, Inge; Jeffery, Penny L; Thomas, Patrick B; Walpole, Carina M; Maugham, Michelle; Fung, Jenny N T; Yap, Pei-Yi; O'Keeffe, Angela J; Lai, John; Whiteside, Eliza J; Herington, Adrian C; Chopin, Lisa K

    2016-06-01

    The peptide hormone ghrelin is a potent orexigen produced predominantly in the stomach. It has a number of other biological actions, including roles in appetite stimulation, energy balance, the stimulation of growth hormone release and the regulation of cell proliferation. Recently, several ghrelin gene splice variants have been described. Here, we attempted to identify conserved alternative splicing of the ghrelin gene by cross-species sequence comparisons. We identified a novel human exon 2-deleted variant and provide preliminary evidence that this splice variant and in1-ghrelin encode a C-terminally truncated form of the ghrelin peptide, termed minighrelin. These variants are expressed in humans and mice, demonstrating conservation of alternative splicing spanning 90 million years. Minighrelin appears to have similar actions to full-length ghrelin, as treatment with exogenous minighrelin peptide stimulates appetite and feeding in mice. Forced expression of the exon 2-deleted preproghrelin variant mirrors the effect of the canonical preproghrelin, stimulating cell proliferation and migration in the PC3 prostate cancer cell line. This is the first study to characterise an exon 2-deleted preproghrelin variant and to demonstrate sequence conservation of ghrelin gene-derived splice variants that encode a truncated ghrelin peptide. This adds further impetus for studies into the alternative splicing of the ghrelin gene and the function of novel ghrelin peptides in vertebrates.

  12. Prion-derived copper-binding peptide fragments catalyze the generation of superoxide anion in the presence of aromatic monoamines

    Directory of Open Access Journals (Sweden)

    Tomonori Kawano

    2007-01-01

    Full Text Available Objectives: Studies have proposed two opposing roles for copper-bound forms of prion protein (PrP as an anti-oxidant supporting the neuronal functions and as a pro-oxidant leading to neurodegenerative process involving the generation of reactive oxygen species. The aim of this study is to test the hypothesis in which putative copper-binding peptides derived from PrP function as possible catalysts for monoamine-dependent conversion of hydrogen peroxide to superoxide in vitro. Materials and methods: Four peptides corresponding to the copper (II-binding motifs in PrP were synthesized and used for analysis of peptide-catalyzed generation of superoxide in the presence of Cu (II and other factors naturally present in the neuronal tissues. Results: Among the Cu-binding peptides tested, the amino acid sequence corresponding to the Cu-binding site in the helical region was shown to be the most active for superoxide generation in the presence of Cu(II, hydrogen peroxide and aromatic monoamines, known precursors or intermediates of neurotransmitters. Among monoamines tested, three compounds namely phenylethylamine, tyramine and benzylamine were shown to be good substrates for superoxide-generating reactions by the Cu-bound helical peptide. Conclusions: Possible roles for these reactions in development of prion disease were suggested.

  13. N-acylated peptides derived from human lactoferricin perturb organization of cardiolipin and phosphatidylethanolamine in cell membranes and induce defects in Escherichia coli cell division.

    Directory of Open Access Journals (Sweden)

    Dagmar Zweytick

    Full Text Available Two types of recently described antibacterial peptides derived from human lactoferricin, either nonacylated or N-acylated, were studied for their different interaction with membranes of Escherichia coli in vivo and in model systems. Electron microscopy revealed striking effects on the bacterial membrane as both peptide types induced formation of large membrane blebs. Electron and fluorescence microscopy, however demonstrated that only the N-acylated peptides partially induced the generation of oversized cells, which might reflect defects in cell-division. Further a different distribution of cardiolipin domains on the E. coli membrane was shown only in the presence of the N-acylated peptides. The lipid was distributed over the whole bacterial cell surface, whereas cardiolipin in untreated and nonacylated peptide-treated cells was mainly located at the septum and poles. Studies with bacterial membrane mimics, such as cardiolipin or phosphatidylethanolamine revealed that both types of peptides interacted with the negatively charged lipid cardiolipin. The nonacylated peptides however induced segregation of cardiolipin into peptide-enriched and peptide-poor lipid domains, while the N-acylated peptides promoted formation of many small heterogeneous domains. Only N-acylated peptides caused additional severe effects on the main phase transition of liposomes composed of pure phosphatidylethanolamine, while both peptide types inhibited the lamellar to hexagonal phase transition. Lipid mixtures of phosphatidylethanolamine and cardiolipin revealed anionic clustering by all peptide types. However additional strong perturbation of the neutral lipids was only seen with the N-acylated peptides. Nuclear magnetic resonance demonstrated different conformational arrangement of the N-acylated peptide in anionic and zwitterionic micelles revealing possible mechanistic differences in their action on different membrane lipids. We hypothesized that both peptides kill

  14. N-acylated peptides derived from human lactoferricin perturb organization of cardiolipin and phosphatidylethanolamine in cell membranes and induce defects in Escherichia coli cell division.

    Science.gov (United States)

    Zweytick, Dagmar; Japelj, Bostjan; Mileykovskaya, Eugenia; Zorko, Mateja; Dowhan, William; Blondelle, Sylvie E; Riedl, Sabrina; Jerala, Roman; Lohner, Karl

    2014-01-01

    Two types of recently described antibacterial peptides derived from human lactoferricin, either nonacylated or N-acylated, were studied for their different interaction with membranes of Escherichia coli in vivo and in model systems. Electron microscopy revealed striking effects on the bacterial membrane as both peptide types induced formation of large membrane blebs. Electron and fluorescence microscopy, however demonstrated that only the N-acylated peptides partially induced the generation of oversized cells, which might reflect defects in cell-division. Further a different distribution of cardiolipin domains on the E. coli membrane was shown only in the presence of the N-acylated peptides. The lipid was distributed over the whole bacterial cell surface, whereas cardiolipin in untreated and nonacylated peptide-treated cells was mainly located at the septum and poles. Studies with bacterial membrane mimics, such as cardiolipin or phosphatidylethanolamine revealed that both types of peptides interacted with the negatively charged lipid cardiolipin. The nonacylated peptides however induced segregation of cardiolipin into peptide-enriched and peptide-poor lipid domains, while the N-acylated peptides promoted formation of many small heterogeneous domains. Only N-acylated peptides caused additional severe effects on the main phase transition of liposomes composed of pure phosphatidylethanolamine, while both peptide types inhibited the lamellar to hexagonal phase transition. Lipid mixtures of phosphatidylethanolamine and cardiolipin revealed anionic clustering by all peptide types. However additional strong perturbation of the neutral lipids was only seen with the N-acylated peptides. Nuclear magnetic resonance demonstrated different conformational arrangement of the N-acylated peptide in anionic and zwitterionic micelles revealing possible mechanistic differences in their action on different membrane lipids. We hypothesized that both peptides kill bacteria by

  15. Expression and characterization of preproVIP derived peptides in the human male urogenital tract

    DEFF Research Database (Denmark)

    Ottesen, B; Bredkjaer, H E; Ekblad, E;

    1995-01-01

    Expression of the gene sequence encoding vasoactive intestinal polypeptide (VIP) leads to the synthesis of a 170 amino acid precursor molecule which can be processed to five fragments: preproVIP 22-79, peptide histidine methionine (PHM), or peptide histidine valine (PHV), preproVIP 111-122, VIP...

  16. Chicken cathelicidin-2-derived peptides with enhanced immunomodulatory and antibacterial activities against biological warfare agents

    NARCIS (Netherlands)

    Molhoek, E.M.; van Dijk, A.; Veldhuizen, E.J.A.; Dijk-Knijnenburg, H.; Mars-Groenendijk, R.H.; Boele, L.C.L.; Kaman, W.E.; Haagsman, H.P.; Bikker, F.J.

    2010-01-01

    Host defence peptides (HDPs) are considered to be excellent candidates for the development of novel therapeutic agents. Recently, it was demonstrated that the peptide C1-15, an N-terminal segment of chicken HDP cathelicidin-2, exhibits potent antibacterial activity while lacking cytotoxicity towards

  17. New Milk Protein-Derived Peptides with Potential Antimicrobial Activity: An Approach Based on Bioinformatic Studies

    Science.gov (United States)

    Dziuba, Bartłomiej; Dziuba, Marta

    2014-01-01

    New peptides with potential antimicrobial activity, encrypted in milk protein sequences, were searched for with the use of bioinformatic tools. The major milk proteins were hydrolyzed in silico by 28 enzymes. The obtained peptides were characterized by the following parameters: molecular weight, isoelectric point, composition and number of amino acid residues, net charge at pH 7.0, aliphatic index, instability index, Boman index, and GRAVY index, and compared with those calculated for known 416 antimicrobial peptides including 59 antimicrobial peptides (AMPs) from milk proteins listed in the BIOPEP database. A simple analysis of physico-chemical properties and the values of biological activity indicators were insufficient to select potentially antimicrobial peptides released in silico from milk proteins by proteolytic enzymes. The final selection was made based on the results of multidimensional statistical analysis such as support vector machines (SVM), random forest (RF), artificial neural networks (ANN) and discriminant analysis (DA) available in the Collection of Anti-Microbial Peptides (CAMP database). Eleven new peptides with potential antimicrobial activity were selected from all peptides released during in silico proteolysis of milk proteins. PMID:25141106

  18. Alpha-amidated peptides derived from pro-opiomelanocortin in normal human pituitary

    DEFF Research Database (Denmark)

    Fenger, M; Johnsen, A H

    1988-01-01

    Normal human pituitaries were extracted in boiling water and acetic acid, and the alpha-amidated peptide products of pro-opiomelanocortin (POMC), alpha-melanocyte-stimulating hormone (alpha MSH), gamma-melanocyte-stimulating hormone (gamma 1MSH), and amidated hinge peptide (HP-N), as well...

  19. New Milk Protein-Derived Peptides with Potential Antimicrobial Activity: An Approach Based on Bioinformatic Studies

    Directory of Open Access Journals (Sweden)

    Bartłomiej Dziuba

    2014-08-01

    Full Text Available New peptides with potential antimicrobial activity, encrypted in milk protein sequences, were searched for with the use of bioinformatic tools. The major milk proteins were hydrolyzed in silico by 28 enzymes. The obtained peptides were characterized by the following parameters: molecular weight, isoelectric point, composition and number of amino acid residues, net charge at pH 7.0, aliphatic index, instability index, Boman index, and GRAVY index, and compared with those calculated for known 416 antimicrobial peptides including 59 antimicrobial peptides (AMPs from milk proteins listed in the BIOPEP database. A simple analysis of physico-chemical properties and the values of biological activity indicators were insufficient to select potentially antimicrobial peptides released in silico from milk proteins by proteolytic enzymes. The final selection was made based on the results of multidimensional statistical analysis such as support vector machines (SVM, random forest (RF, artificial neural networks (ANN and discriminant analysis (DA available in the Collection of Anti-Microbial Peptides (CAMP database. Eleven new peptides with potential antimicrobial activity were selected from all peptides released during in silico proteolysis of milk proteins.

  20. Impact of the erythropoietin-derived peptide mimetic Epotris on the histopathological consequences of status epilepticus

    DEFF Research Database (Denmark)

    Zellinger, Christina; Seeger, Natalie; Hadamitzky, Martin;

    2011-01-01

    of this peptide to interfere with the histopathological consequences of electrical-induced status epilepticus in rats. The peptide attenuated status epilepticus-associated expansion of the neuronal progenitor cell population in a significant manner. Moreover, Epotris affected the number of persistent basal...

  1. Chicken cathelicidin-2-derived peptides with enhanced immunomodulatory and antibacterial activities against biological warfare agents

    NARCIS (Netherlands)

    Molhoek, E.M.; Dijk, A. van; Veldhuizen, E.J.A.; Dijk-Knijnenburg, H.; Mars-Groenendijk, R.H.; Boele, L.C.L.; Kaman-van Zanten, W.E.; Haagsman, H.P.; Bikker, F.J.

    2010-01-01

    Host defence peptides (HDPs) are considered to be excellent candidates for the development of novel therapeutic agents. Recently, it was demonstrated that the peptide C1-15, an N-terminal segment of chicken HDP cathelicidin-2, exhibits potent antibacterial activity while lacking cytotoxicity towards

  2. Fertility and pregnancy-associated ß-cell proliferation in mice deficient in proglucagon-derived peptides.

    Directory of Open Access Journals (Sweden)

    Chisato Sugiyama

    Full Text Available Proglucagon, which is encoded by the glucagon gene (Gcg, is the precursor of several peptide hormones, including glucagon and glucagon-like peptide 1 (GLP-1. Whereas glucagon stimulates hepatic glycogenolysis and gluconeogenesis, GLP-1 stimulates insulin secretion to lower blood glucose and also supports ß-cell proliferation and protection from apoptotic stimuli. Pregnancy is a strong inducer of change in islet function, however the roles of proglucagon-derived peptides in pregnancy are only partially understood. In the present study, we analyzed fertility and pregnancy-associated changes in homozygous glucagon-green fluorescent protein (gfp knock-in mice (Gcg(gfp/gfp, which lack all the peptides derived from proglucagon. Female Gcg(gfp/gfp mice could deliver and raise Gcg(gfp/gfp pups to weaning and Gcg(gfp/gfp pups from Gcg(gfp/gfp dams were viable and fertile. Pregnancy induced ß-cell proliferation in Gcg(gfp/gfp mice as well as in control mice. However, serum insulin levels in pregnant Gcg(gfp/gfp females were lower than those in control pregnant females under ad libitum feeding, and blood glucose levels in pregnant Gcg(gfp/gfp females were higher after gestational day 12. Gcg(gfp/gfp females showed a decreased pregnancy rate and smaller litter size. The rate of successful breeding was significantly lower in Gcg(gfp/gfp females and was not improved by experience of breeding. Taken together, proglucagon-derived peptides are not required for pregnancy-associated ß-cell proliferation, however, are required for regulation of blood glucose levels and normal reproductive capacity. Gcg(gfp/gfp mice may serve as a novel model to analyze the effect of mild hyperglycemia during late gestational periods.

  3. A preliminary study on the antibacterial mechanism of Tegillarca granosa hemoglobin by derived peptides and peroxidase activity.

    Science.gov (United States)

    Bao, Yongbo; Wang, Juanjuan; Li, Chenghua; Li, Peifen; Wang, Sufang; Lin, Zhihua

    2016-04-01

    The blood clam, Tegillarca granosa, is one of the few bivalve molluscs containing hemoglobin (Hb). In the present study, we purified two types of T. granosa hemoglobin, Tg-HbI and Tg-HbII, using size exclusion chromatography and measured their antibacterial and peroxidase activities. We also tested antibacterial activities of peptides prepared by trypsin digestion of purified Tg-Hb and reversed-phase high-performance liquid chromatography purification. Purified Tg-HbI and Tg-HbII showed antibacterial activity against Escherichia coli, Pseudomonas putida, Bacillus subtilis, and Bacillus firmus, with differences in minimal inhibitory concentrations (MICs), but lacked antibacterial activity against Vibrio alginolyticus, Vibrio parahaemolyticus, Vibrio harveyi and Staphylococcus aureus. In contrast, 7 Tg-Hb derived peptides exhibited varying degrees of antibacterial activity against V. alginolyticus (MICs: 12-200 μg/ml), V. parahaemolyticus (11-100 μg/ml) and V. harveyi (1-200 μg/ml). The antibacterial activity of Hb derived peptides was confirmed by fluorescence microscopy. In addition, peroxidase activity was detected in Tg-HbI and Tg-HbII. The results indicated that in addition to functioning as a respiratory protein T. granosa hemoglobins likely play a role in host antibacterial defense probably via a peroxidase activity of native molecules and some internal peptides released from the proteins.

  4. Targeting of liposomes to HIV-1-infected cells by peptides derived from the CD4 receptor.

    Science.gov (United States)

    Slepushkin, V A; Salem, I I; Andreev, S M; Dazin, P; Düzgüneş, N

    1996-10-23

    Liposomes can be targeted to HIV-infected cells by either reconstituting transmembrane CD4 in the membrane or covalently coupling soluble CD4 to modified lipids. We investigated whether synthetic peptides could be used as ligands for targeting liposomes. A synthetic peptide from the complementarity determining region 2 (CDR-2)-like domain of CD4 could bind specifically to HIV-infected cells and mediate the binding of peptide-coupled liposomes to these cells. A peptide from the CDR-3-like domain of CD4 inhibited HIV-induced syncytia formation, but failed to target liposomes to infected cells. This apparent discrepancy may be due to the requirement for a conformational change in the CD4 receptor for the CDR-3 region to interact with the HIV envelope protein. Our results demonstrate the feasibility of using synthetic peptides to target liposomes containing antiviral drugs to HIV-infected cells.

  5. Epigenetic Silencing of CXCR4 Promotes Loss of Cell Adhesion in Cervical Cancer

    Directory of Open Access Journals (Sweden)

    Suresh Singh Yadav

    2014-01-01

    Full Text Available In the network of chemokine signaling pathways, recent reports have described the SDF-1α/CXCR4 axis and its role in cancer progression and metastasis. Interestingly, we found downregulation of CXCR4 at both transcript and protein level in cervical cancer cell lines and primary tumors. We also found CXCR4 promoter hypermethylation in cervical cancer cell lines and primary biopsy samples. DNA hypomethylating drug 5-AZA-2′-deoxycytidine and histone deacetylase inhibitor Trichostatin A treatments in cell lines reactivate both CXCR4 transcription and protein expression. Cell adhesion assay demonstrated that autocrine SDF-1α promotes the loss of cell adhesion while paracrine SDF-1α predominantly protects the normal cervical cells from loss of cell adhesion. Cervical cancer cell line C-33A having increased expression of CXCR4 after TSA treatment showed increased cell adhesion by paracrine source of SDF-1α in comparison to untreated C-33A. These findings demonstrate the first evidence that epigenetic silencing of CXCR4 makes the cells inefficient to respond to the paracrine source of SDF-1α leading to loss of cell adhesion, one of the key events in metastases and progression of the disease. Our results provide novel insight of SDF-1α/CXCR4 signaling in tumor microenvironment which may be promising to further delineate molecular mechanism of cervical carcinogenesis.

  6. Hepatoprotective effects of rice-derived peptides against acetaminophen-induced damage in mice.

    Science.gov (United States)

    Kawakami, Kayoko; Moritani, Chie; Uraji, Misugi; Fujita, Akiko; Kawakami, Koji; Hatanaka, Tadashi; Suzaki, Etsuko; Tsuboi, Seiji

    2017-03-01

    Glutathione, the most abundant intracellular antioxidant, protects cells against reactive oxygen species induced oxidative stress and regulates intracellular redox status. We found that rice peptides increased intracellular glutathione levels in human hepatoblastoma HepG2 cells. Acetaminophen is a commonly used analgesic. However, an overdose of acetaminophen causes severe hepatotoxicity via depletion of hepatic glutathione. Here, we investigated the protective effects of rice peptides on acetaminophen-induced hepatotoxicity in mice. ICR mice were orally administered rice peptides (0, 100 or 500 mg/kg) for seven days, followed by the induction of hepatotoxicity via intraperitoneal injection of acetaminophen (700 mg/kg). Pretreatment with rice peptides significantly prevented increases in serum alanine aminotransferase, aspartate aminotransferase, and lactate dehydrogenase levels and protected against hepatic glutathione depletion. The expression of γ-glutamylcysteine synthetase, a key regulatory enzyme in the synthesis of glutathione, was decreased by treatment with acetaminophen, albeit rice peptides treatment recovered its expression compared to that achieved treatment with acetaminophen. In addition, histopathological evaluation of the livers also revealed that rice peptides prevented acetaminophen-induced centrilobular necrosis. These results suggest that rice peptides increased intracellular glutathione levels and could protect against acetaminophen-induced hepatotoxicity in mice.

  7. Therapeutic Efficacy with Treatment-related Toxicities of {sup 177}Lu-labeled Bombesin Derivative for the Peptide Receptor Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Jae Cheong; Cho, Eun Ha; Lee, So Young [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    The gastrin-releasing peptide receptor (GRPR) has been shown to be overexpressed in many human tumours, including breast cancer, prostate cancer, small cell lung cancer, ovarian cancers, endometrial cancers, and gastrointestinal stromal tumors. In particular, GRPR expression is high in 83 % of invasive primary prostatic carcinomas. These results suggest that {sup 177}Lu-labeled bombesin derivative has promising characteristics as a novel nuclear medicine, especially for the treatment of GRPR over-expressing prostate tumors.

  8. E-selectin ligand-1 (ESL-1) is a novel adiponectin binding protein on cell adhesion

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Hiroyasu; Kuroda, Nana; Uekita, Hiromi; Kochi, Ikoi; Matsumoto, Akane; Niinaga, Ryu [Department of Biomedical Informatics, Division of Health Sciences, Osaka University Graduate School of Medicine, Osaka (Japan); Funahashi, Tohru; Shimomura, Iichiro [Department of Metabolic Medicine, Osaka University Graduate School of Medicine, Osaka (Japan); Kihara, Shinji, E-mail: skihara@sahs.med.osaka-u.ac.jp [Department of Biomedical Informatics, Division of Health Sciences, Osaka University Graduate School of Medicine, Osaka (Japan)

    2016-02-05

    Background: Adiponectin (APN) is an adipocyte-derived bioactive molecule with anti-diabetic and anti-atherogenic properties. Although anti-diabetic effects are mostly mediated by the adiponectin receptors AdipoR1 and AdipoR2, the anti-atherogenic mechanisms have not been fully elucidated. Methods and Results: In this study, we identified E-selectin ligand (ESL)-1 as a novel APN-binding protein by mass spectrometry analysis of HepG2 cell-derived immunoprecipitant with an anti-APN antibody. Cell adhesion assays using fluorescence-labelled monocyte cell line THP-1 cells and human umbilical vein endothelial cells (HUVECs) revealed that APN-pre-treated THP-1 cells had reduced binding ability to HUVECs. This APN-mediated suppressive effect on monocyte binding to endothelial cells was partially abrogated by targeting ESL-1 with shRNA in THP-1 cells. In addition, serial mutagenesis analysis disclosed that five extracellular amino acids close to the N-terminus of ESL-1 were essential for binding with APN. Conclusion: Our results highlight the fact that interaction between APN and ESL-1 could provide a fundamental mechanism underlying the anti-atherogenic properties of APN. - Highlights: • E-selectin ligand (ESL)-1 was identified as an adiponectin (APN)-binding protein. • ESL-1 bound to APN at its N-terminal 6th-10th amino acids. • shESL-1 reduced the suppressive effect of APN on adhesion of THP-1 cells to HUVECs. • Interaction with ESL may be involved in the anti-atherogenic effects of APN.

  9. Reference intervals for C-peptide and insulin derived from a general adult Danish population

    DEFF Research Database (Denmark)

    Larsen, Pia Bükmann; Linneberg, Allan; Hansen, Torben

    2016-01-01

    BACKGROUND: Despite international efforts to standardize C-peptide and insulin calibrators and immunoassays, platform dependent differences still exist, and platform specific reference intervals are hence needed for correct interpretation. We therefore wanted to establish traceable reference...... intervals for C-peptide and insulin. METHODS: In 623 consecutively recruited participants, insulin and C-peptide were measured using the Cobas e411 (Roche Diagnostics, Switzerland). Participants with diabetes were excluded (fasting Glucose ≥7.0mmol/L or HbA1c≥6.5%/≥48mmol/L) and reference intervals were...

  10. Metabolism of cryptic peptides derived from neuropeptide FF precursors: the involvement of insulin-degrading enzyme.

    Science.gov (United States)

    Grasso, Giuseppe; Mielczarek, Przemyslaw; Niedziolka, Magdalena; Silberring, Jerzy

    2014-09-22

    The term "cryptome" refers to the subset of cryptic peptides with bioactivities that are often unpredictable and very different from the parent protein. These cryptic peptides are generated by proteolytic cleavage of proteases, whose identification in vivo can be very challenging. In this work, we show that insulin-degrading enzyme (IDE) is able to degrade specific amino acid sequences present in the neuropeptide pro-NPFFA (NPFF precursor), generating some cryptic peptides that are also observed after incubation with rat brain cortex homogenate. The reported experimental findings support the increasingly accredited hypothesis, according to which, due to its wide substrate selectivity, IDE is involved in a wide variety of physiopathological processes.

  11. Pyroacm Resin: An Acetamidomethyl Derived Resin for Solid Phase Synthesis of Peptides through Side Chain Anchoring of C-Terminal Cysteine Residues.

    Science.gov (United States)

    Juvekar, Vinayak; Gong, Young Dae

    2016-02-19

    The design, synthesis and utilization of an efficient acetamidomethyl derived resin for the peptide synthesis is presented using established Fmoc and Boc protocols via side chain anchoring. Cleavage of the target peptide from the resin is performed using carboxymethylsulfenyl chloride under mild conditions which gave in situ thiol-sulfenyl protection of the cysteine residues. The utility of the resin is successfully demonstrated through applications to the syntheses of model peptides and natural products Riparin 1.1 and Riparin 1.2.

  12. Cellular recognition of synthetic peptide amphiphiles in supported bioartificial membranes

    Science.gov (United States)

    Pakalns, Teika

    The goal of this study was to demonstrate that lipidated cell adhesion peptides could form well-ordered biomimetic surfaces that were capable of influencing cellular behavior in a controlled and specific manner. The first step taken was to covalently link synthetic dialkyl tails to the amino-termini of the collagen-derived peptide IV-H1 (amino acid sequence GVKGDKGNPGWPGAP) and the well-known tripeptide Arg-Gly-Asp (RGD) to produce amino-coupled peptide amphiphiles. Other spatial orientations of RGD were also generated by coupling tails to the carboxyl-terminus to give carboxyl-coupled RGD amphiphiles and to both the amino- and carboxyl-termini to give looped RGD amphiphiles. The next step taken was to let the peptide amphiphile self-assemble along with methyl ester-capped dialkyl tails into mixed films. It was found that all the peptide amphiphiles formed stable monolayers at the air-water interface in a Langmuir trough. IV-H1 amphiphiles and carboxyl-coupled and looped RGD amphiphiles deposited well as Langmuir-Blodgett mixed films on solid surfaces at all peptide concentrations, but aminocoupled RGD amphiphiles did not deposit well at high RGD concentrations. FT-IR studies of films containing RGD amphiphiles showed that amino-coupled RGD head groups formed the strongest lateral hydrogen bonds. The final step was to study cellular response to mixed films containing IV-H1 or RGD amphiphiles. The spreading of melanoma cells was influenced by both the molar concentration and spatial orientation of the amphiphilic peptides. Cells spread on IV-H1 and looped RGD films in a concentration-dependent manner, but spread indiscriminately on carboxyl-coupled RGD films and did not spread at all on well-deposited amino-coupled RGD films. The specificity of the cellular response to looped RGD amphiphiles was investigated. Control films of looped Arg-Gly-Glu (RGE) amphiphiles inhibited the adhesion and spreading of melanoma and endothelial cells, and antibody inhibition of the

  13. Osteoinductive peptide-functionalized nanofibers with highly ordered structure as biomimetic scaffolds for bone tissue engineering.

    Science.gov (United States)

    Gao, Xiang; Zhang, Xiaohong; Song, Jinlin; Xu, Xiao; Xu, Anxiu; Wang, Mengke; Xie, Bingwu; Huang, Enyi; Deng, Feng; Wei, Shicheng

    2015-01-01

    The construction of functional biomimetic scaffolds that recapitulate the topographical and biochemical features of bone tissue extracellular matrix is now of topical interest in bone tissue engineering. In this study, a novel surface-functionalized electrospun polycaprolactone (PCL) nanofiber scaffold with highly ordered structure was developed to simulate the critical features of native bone tissue via a single step of catechol chemistry. Specially, under slightly alkaline aqueous solution, polydopamine (pDA) was coated on the surface of aligned PCL nanofibers after electrospinning, followed by covalent immobilization of bone morphogenetic protein-7-derived peptides onto the pDA-coated nanofiber surface. Contact angle measurement, Raman spectroscopy, and X-ray photoelectron spectroscopy confirmed the presence of pDA and peptides on PCL nanofiber surface. Our results demonstrated that surface modification with osteoinductive peptides could improve cytocompatibility of nanofibers in terms of cell adhesion, spreading, and proliferation. Most importantly, Alizarin Red S staining, quantitative real-time polymerase chain reaction, immunostaining, and Western blot revealed that human mesenchymal stem cells cultured on aligned nanofibers with osteoinductive peptides exhibited enhanced osteogenic differentiation potential than cells on randomly oriented nanofibers. Furthermore, the aligned nanofibers with osteoinductive peptides could direct osteogenic differentiation of human mesenchymal stem cells even in the absence of osteoinducting factors, suggesting superior osteogenic efficacy of biomimetic design that combines the advantages of osteoinductive peptide signal and highly ordered nanofibers on cell fate decision. The presented peptide-decorated bone-mimic nanofiber scaffolds hold a promising potential in the context of bone tissue engineering.

  14. Generation of functional HLA-DR*1101 tetramers receptive for loading with pathogen or tumour derived synthetic peptides

    Directory of Open Access Journals (Sweden)

    Protti Maria

    2005-12-01

    Full Text Available Abstract Background MHC class I-peptide tetramers are currently utilised to characterize CD8+ T cell responses at single cell level. The generation and use of MHC class II tetramers to study antigen-specific CD4+ T cells appears less straightforward. Most MHC class II tetramers are produced with a homogeneously built-in peptide, reducing greatly their flexibility of use. We attempted the generation of "empty" functional HLA-DR*1101 tetramers, receptive for loading with synthetic peptides by incubation. No such reagent is in fact available for this HLA-DR allele, one of the most frequent in the Caucasian population. Results We compared soluble MHC class II-immunoglobulin fusion proteins (HLA-DR*1101-Ig with soluble MHC class II protein fused with an optimised Bir site for enzymatic biotynilation (HLA-DR*1101-Bir, both produced in insect cells. The molecules were multimerised by binding fluorochrome-protein A or fluorochrome-streptavidin, respectively. We find that HLA-DR*1101-Bir molecules are superior to the HLA-DR*1101-Ig ones both in biochemical and functional terms. HLA-DR*1101-Bir molecules can be pulsed with at least three different promiscuous peptide epitopes, derived from Tetanus Toxoid, influenza HA and the tumour associated antigen MAGE-3 respectively, to stain specific CD4+ T cells. Both staining temperature and activation state of CD4+ T cells are critical for the binding of peptide-pulsed HLA-DR*1101-Bir to the cognate TCR. Conclusion It is therefore possible to generate a soluble recombinant HLA-DR*1101 backbone that is receptive for loading with different peptides to stain specific CD4+ T cells. As shown for other HLA-DR alleles, we confirm that not all the strategies to produce soluble HLA-DR*1101 multimers are equivalent.

  15. Evaluation of single amino acid chelate derivatives and regioselective radiolabelling of a cyclic peptide for the urokinase plasminogen activator receptor

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, Andrea F.; Lemon, Jennifer A. [McMaster Institute for Applied Radiation Sciences, McMaster University, ON, L8S 4M1 (Canada); Czorny, Shannon K. [McMaster Institute for Applied Radiation Sciences, McMaster University, ON, L8S 4M1 (Canada); Juravinski Cancer Centre, Hamilton, ON, L8V 5C2 (Canada); Singh, Gurmit [Juravinski Cancer Centre, Hamilton, ON, L8V 5C2 (Canada); Valliant, John F. [Department of Chemistry, McMaster University, Hamilton, ON, L8S 4M1 (Canada); Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, ON, L8S 4M1 (Canada)], E-mail: valliant@mcmaster.ca

    2009-11-15

    Introduction: The aim of this work was to investigate the relative radiolabelling kinetics and affinity of a series of ligands for the [{sup 99m}Tc(CO){sub 3}]{sup +} core, both in the absence and in the presence of competing donors. This information was used to select a suitable ligand for radiolabelling complex peptide-based targeting vectors in high yield under mild conditions. Methods: A series of {alpha}-N-Fmoc-protected lysine derivatives bearing two heterocyclic donor groups at the {epsilon}-amine (, 2-pyridyl; , quinolyl; , 6-methoxy-2-pyridyl; 1d, 2-thiazolyl; 1e, N-methylimidazolyl; , 3-pyridyl) were synthesized and labelled with {sup 99m}Tc. A resin-capture purification strategy for the separation of residual ligand from the radiolabelled product was also developed. The binding affinities of targeted peptides 4, 5a and 5b for uPAR were determined using flow cytometry. Results: Variable temperature radiolabelling reactions using - and [{sup 99m}Tc(CO){sub 3}]{sup +} revealed optimal kinetics and good selectivity for compounds and 1d; in the case of , 1d, and 1e, the labelling can be conducted at ambient temperature. The utility of this class of ligands was further demonstrated by the radiolabelling of a cyclic peptide that is known to target the serine protease receptor uPAR; essentially quantitative incorporation of {sup 99m}Tc occurred exclusively at the SAAC site, despite the presence of a His residue, and without disruption of the disulfide bond. Conclusion: A series of single amino acid chelate (SAAC) ligands have been evaluated for their ability to incorporate {sup 99m}Tc into peptides. The lead agent to emerge from this work is the thiazole SAAC derivative 1d which has demonstrated the ability to regioselectively label the widest range of peptides.

  16. Tumor-derived heat shock protein 70 peptide complexes are cross-presented by human dendritic cells.

    Science.gov (United States)

    Noessner, Elfriede; Gastpar, Robert; Milani, Valeria; Brandl, Anna; Hutzler, Peter J S; Kuppner, Maria C; Roos, Miriam; Kremmer, Elisabeth; Asea, Alexzander; Calderwood, Stuart K; Issels, Rolf D

    2002-11-15

    Our study demonstrates that tumor-derived heat shock protein (HSP)70 chaperones a tyrosinase peptide and mediates its transfer to human immature dendritic cells (DCs) by receptor-dependent uptake. Human tumor-derived HSP70 peptide complexes (HSP70-PC) thus have the immunogenic potential to instruct DCs to cross-present endogenously expressed, nonmutated, and tumor antigenic peptides that are shared among tumors of the melanocytic lineage for T cell recognition. T cell stimulation by HSP70-instructed DCs is dependent on the Ag bound to HSP70 in that only DCs incubated with HSP70-PC purified from tyrosinase-positive (HSP70-PC/tyr(+)) but not from tyrosinase-negative (HSP70-PC/tyr(-)) melanoma cells resulted in the specific activation of the HLA-A*0201-restricted tyrosinase peptide-specific cytotoxic T cell clone. HSP70-PC-mediated T cell stimulation is very efficient, delivering the tyrosinase peptide at concentrations as low as 30 ng/ml of HSP70-PC for T cell recognition. Receptor-dependent binding of HSP70-PC and active cell metabolism are prerequisites for MHC class I-restricted cross-presentation and T cell stimulation. T cell stimulation does not require external DC maturation signals (e.g., exogenously added TNF-alpha), suggesting that signaling DC maturation is an intrinsic property of the HSP70-PC itself and related to receptor-mediated binding. The cross-presentation of a shared human tumor Ag together with the exquisite efficacy are important new aspects for HSP70-based immunotherapy in clinical anti-cancer vaccination strategies, and suggest a potential extension of HSP70-based vaccination protocols from a patient-individual treatment modality to its use in an allogeneic setting.

  17. Characterization of novel breast carcinoma–associated BA46-derived peptides in HLA-A2.1/Db-β2mtransgenic mice

    Science.gov (United States)

    Carmon, Lior; Bobilev-Priel, Irene; Brenner, Baruch; Bobilev, Dimitry; Paz, Adrian; Bar-Haim, Erez; Tirosh, Boaz; Klein, Tirza; Fridkin, Mati; Lemonnier, Francois; Tzehoval, Esther; Eisenbach, Lea

    2002-01-01

    The human milk fat globule membrane protein BA46 (lactadherin) is highly overexpressed in human breast tumors, making it a potential target for tumor immunotherapy. We have identified BA46-derived peptides that contain the motif recognized by the MHC class I molecule HLA-A2.1 and that are processed and presented by human breast carcinoma cells. In mice lacking normal class I molecules but expressing an HLA-A2.1/Db-β2 microglobulin single chain (HHD mice), three peptides elicited specific CTL activity. Two of these peptides also stimulated cytotoxic activity in peripheral blood lymphocytes from HLA-A2.1–positive breast carcinoma patients. Adoptive transfer of HHD-derived bulk CTLs to nude mice bearing human breast carcinoma transplants reduced tumor growth. These peptides therefore represent naturally processed BA46-derived CTL epitopes that can be used in peptide-based antitumor vaccines. PMID:12189239

  18. Cell adhesion of F{sup +} ion implantation of intraocular lens

    Energy Technology Data Exchange (ETDEWEB)

    Li, D.J. E-mail: dejunli@hotmail.com; Cui, F.Z.; Gu, H.Q

    1999-04-01

    The cell adhesion of ion implanted polymethylmethacrylate (PMMA) intraocular lens was studied using cultured cells in vitro. F{sup +} ion implantation was performed at the energies of 40, 60, 80, 100 keV with the fluences ranging from 5x10{sup 13} to 1x10{sup 15} ions/cm{sup 2} at room temperature. The cell adhesion tests gave interesting results that the number of the neutral granulocytes and the macrophages adhering on surface were reduced significantly after ion implantation. The optimal fluence was about 4x10{sup 14} ions/cm{sup 2}. The hydrophobicity imparted to the lens surface was also enhanced. The results of X-ray photoelectron spectroscopy analysis indicated that ion implantation resulted in the cleavage of some pendant groups, the oxidation of the surface, and the formation of some new chemical bonds, which was probably the main reason for the cell adhesion change.

  19. A role for cell adhesion in beryllium-mediated lung disease

    Energy Technology Data Exchange (ETDEWEB)

    Hong-geller, Elizabeth [Los Alamos National Laboratory

    2008-01-01

    Chronic beryllium disease (CBD) is a debilitating lung disorder in which exposure to the lightweight metal beryllium (Be) causes the accumulation of beryllium-specific CD4+ T cells in the lung and formation of noncaseating pulmonary granulomas. Treatment for CBD patients who exhibit progressive pulmonary decline is limited to systemic corticosteroids, which suppress the severe host inflammatory response. Studies in the past several years have begun to highlight cell-cell adhesion interactions in the development of Be hypersensitivity and CBD. In particular, the high binding affinity between intercellular adhesion molecule 1 (I-CAM1) on lung epithelial cells and the {beta}{sub 2} integrin LFA-1 on migrating lymphocytes and macrophages regulates the concerted rolling of immune cells to sites of inflammation in the lung. In this review, we discuss the evidence that implicates cell adhesion processes in onset of Be disease and the potential of cell adhesion as an intervention point for development of novel therapies.

  20. The Role of Lipid Rafts in Cancer Cell Adhesion and Migration

    Directory of Open Access Journals (Sweden)

    Toshiyuki Murai

    2012-01-01

    Full Text Available Lipid rafts are cholesterol-enriched microdomains of the cell membrane and possess a highly dynamic nature. They have been involved in various cellular functions including the regulation of cell adhesion and membrane signaling through proteins within lipid rafts. The dynamic features of the cancer cell surface may modulate the malignant phenotype of cancer, including adhesion disorders and aggressive phenotypes of migration and invasion. Recently, it was demonstrated that lipid rafts play critical roles in cancer cell adhesion and migration. This article summarizes the important roles of lipid rafts in cancer cell adhesion and migration, with a focus on the current state of knowledge. This article will improve the understanding of cancer progression and lead to the development of novel targets for cancer therapy.

  1. Preparation and regulating cell adhesion of anion-exchangeable layered double hydroxide micropatterned arrays.

    Science.gov (United States)

    Yao, Feng; Hu, Hao; Xu, Sailong; Huo, Ruijie; Zhao, Zhiping; Zhang, Fazhi; Xu, Fujian

    2015-02-25

    We describe a reliable preparation of MgAl-layered double hydroxide (MgAl-LDH) micropatterned arrays on gold substrate by combining SO3(-)-terminated self-assembly monolayer and photolithography. The synthesis route is readily extended to prepare LDH arrays on the SO3(-)-terminated polymer-bonded glass substrate amenable for cell imaging. The anion-exchangeable MgAl-LDH micropattern can act both as bioadhesive region for selective cell adhesion and as nanocarrier for drug molecules to regulate cell behaviors. Quantitative analysis of cell adhesion shows that selective HepG2 cell adhesion and spreading are promoted by the micropatterned MgAl-LDH, and also suppressed by methotrexate drug released from the LDH interlayer galleries.

  2. Caspases and p38 MAPK regulate endothelial cell adhesiveness for mesenchymal stem cells.

    Directory of Open Access Journals (Sweden)

    Irina A Potapova

    Full Text Available Mesenchymal stem cells natively circulating or delivered into the blood stream home to sites of injury. The mechanism of mesenchymal stem cell homing to sites of injury is poorly understood. We have shown that the development of apoptosis in endothelial cells stimulates endothelial cell adhesiveness for mesenchymal stem cells. Adhesion of mesenchymal stem cells to apoptotic endothelial cells depends on the activation of endothelial caspases and p38 MAPK. Activation of p38 MAPK in endothelial cells has a primary effect while the activation of caspases potentiates the mesenchymal stem cell adhesion. Overall, our study of the mesenchymal stem cell interaction with endothelial cells indicates that mesenchymal stem cells recognize and specifically adhere to distressed/apoptotic endothelial cells.

  3. Comparative analysis of human milk and infant formula derived peptides following in vitro digestion.

    Science.gov (United States)

    Su, M-Y; Broadhurst, M; Liu, C-P; Gathercole, J; Cheng, W-L; Qi, X-Y; Clerens, S; Dyer, J M; Day, L; Haigh, B

    2017-04-15

    It has long been recognised that there are differences between human milk and infant formulas which lead to differences in health and nutrition for the neonate. In this study we examine and compare the peptide profile of human milk and an exemplar infant formula. The study identifies both similarities and differences in the endogenous and postdigestion peptide profiles of human milk and infant formula. This includes differences in the protein source of these peptides but also with the region within the protein producing the dominant proteins. Clustering of similar peptides around regions of high sequence identity and known bioactivity was also observed. Together the data may explain some of the functional differences between human milk and infant formula, while identifying some aspects of conserved function between bovine and human milks which contribute to the effectiveness of modern infant formula as a substitute for human milk. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Human DMBT1-Derived Cell-Penetrating Peptides for Intracellular siRNA Delivery

    DEFF Research Database (Denmark)

    Tuttolomondo, Martina; Casella, Cinzia; Hansen, Pernille Lund

    2017-01-01

    Small interfering RNA (siRNA) is a promising molecule for gene therapy, but its therapeutic administration remains problematic. Among the recently proposed vectors, cell-penetrating peptides show great promise in in vivo trials for siRNA delivery. Human protein DMBT1 (deleted in malignant brain...... an electrophoretic mobility shift assay and UV spectra, we identified two DMBT1 peptides that could encapsulate the siRNA with a self- and co-assembly mechanism. The complexes were stable for at least 2 hr in the presence of either fetal bovine serum (FBS) or RNase A, with peptide-dependent time span protection. ζ...... line to exploit DMBT1-peptide nanocomplexes for therapeutic siRNA delivery....

  5. A cactus-derived toxin-like cystine knot Peptide with selective antimicrobial activity.

    Science.gov (United States)

    Aboye, Teshome L; Strömstedt, Adam A; Gunasekera, Sunithi; Bruhn, Jan G; El-Seedi, Hesham; Rosengren, K Johan; Göransson, Ulf

    2015-05-04

    Naturally occurring cystine knot peptides show a wide range of biological activity, and as they have inherent stability they represent potential scaffolds for peptide-based drug design and biomolecular engineering. Here we report the discovery, sequencing, chemical synthesis, three-dimensional solution structure determination and bioactivity of the first cystine knot peptide from Cactaceae (cactus) family: Ep-AMP1 from Echinopsis pachanoi. The structure of Ep-AMP1 (35 amino acids) conforms to that of the inhibitor cystine knot (or knottin) family but represents a novel diverse sequence; its activity was more than 500 times higher against bacterial than against eukaryotic cells. Rapid bactericidal action and liposome leakage implicate membrane permeabilisation as the mechanism of action. Sequence homology places Ec-AMP1 in the plant C6-type of antimicrobial peptides, but the three dimensional structure is highly similar to that of a spider neurotoxin.

  6. Biosynthesis of the D2 cell adhesion molecule: pulse-chase studies in cultured fetal rat neuronal cells

    DEFF Research Database (Denmark)

    Lyles, J M; Norrild, B; Bock, E

    1984-01-01

    D2 is a membrane glycoprotein that is believed to function as a cell adhesion molecule (CAM) in neural cells. We have examined its biosynthesis in cultured fetal rat brain neurones. We found D2-CAM to be synthesized initially as two polypeptides: Mr 186,000 (A) and Mr 136,000 (B). With increasing...... chase times the Mr of both molecules increased to 187,000-201,000 (A) and 137,000-158,000 (B). These were similar to the sizes of D2-CAM labeled with [14C]glucosamine, [3H]fucose and [14C]mannosamine, indicating that the higher Mr species are glycoproteins. In the presence of tunicamycin, which...... pulse or chase times, showing that these molecules are not interconverted. Thus, our data indicate that the neuronal D2-CAM glycoproteins are derived from two mRNAs....

  7. Targeting Leishmania major parasite with peptides derived from a combinatorial phage display library.

    Science.gov (United States)

    Rhaiem, Rafik Ben; Houimel, Mehdi

    2016-07-01

    Cutaneous leishmaniasis (CL) is a global problem caused by intracellular protozoan pathogens of the genus Leishmania for which there are no suitable vaccine or chemotherapy options. Thus, de novo identification of small molecules binding to the Leishmania parasites by direct screening is a promising and appropriate alternative strategy for the development of new drugs. In this study, we used a random linear hexapeptide library fused to the gene III protein of M13 filamentous bacteriophage to select binding peptides to metacyclic promastigotes from a highly virulent strain of Leishmania major (Zymodeme MON-25; MHOM/TN/94/GLC94). After four rounds of stringent selection and amplification, polyclonal and monoclonal phage-peptides directed against L. major metacyclic promastigotes were assessed by ELISA, and the optimal phage-peptides were grown individually and characterized for binding to L. major by monoclonal phage ELISA. The DNA of 42 phage-peptides clones was amplified by PCR, sequenced, and their amino acid sequences deduced. Six different peptide sequences were obtained with frequencies of occurrence ranging from 2.3% to 85.7%. The biological effect of the peptides was assessed in vitro on human monocytes infected with L. major metacyclic promastigotes, and in vivo on susceptible parasite-infected BALB/c mice. The development of cutaneous lesions in the right hind footpads of infected mice after 13 weeks post-infection showed a protection rate of 81.94% with the injected peptide P2. Moreover, Western blots revealed that the P2 peptide interacted with the major surface protease gp63, a protein of 63kDa molecular weight. Moreover, bioinformatics were used to predict the interaction between peptides and the major surface molecule of the L. major. The molecular docking showed that the P2 peptide has the minimum interaction energy and maximum shape complimentarity with the L. major gp63 active site. Our study demonstrated that the P2 peptide occurs at high frequency

  8. Improvement of early cell adhesion on Thai silk fibroin surface by low energy plasma.

    Science.gov (United States)

    Amornsudthiwat, Phakdee; Mongkolnavin, Rattachat; Kanokpanont, Sorada; Panpranot, Joongjai; Wong, Chiow San; Damrongsakkul, Siriporn

    2013-11-01

    Low energy plasma has been introduced to treat the surface of Thai silk fibroin which should be enhanced for cell adhesion due to its native hydrophobic surface. Plasma surface treatment could introduce desirable hydrophilic functionalities on the surface without using any chemicals. In this work, nitrogen glow discharge plasma was generated by a low energy AC50Hz power supply system. The plasma operating conditions were optimized to reach the highest nitrogen active species by using optical emission spectroscopy. X-ray photoelectron spectroscopy (XPS) revealed that amine, hydroxyl, ether, and carboxyl groups were induced on Thai silk fibroin surface after plasma treatment. The results on Fourier transform infrared attenuated total reflection (FTIR-ATR) spectroscopy confirmed that the plasma treated effects were only on the outermost layer since there was no change in the bulk chemistry. The surface topography was insignificantly changed from the detection with atomic force microscopy (AFM). The plasma-treated effects were the improved surface wettability and cell adhesion. After a 90-s treatment, the water contact angle was at 20°, while the untreated surface was at 70°. The early cell adhesion of L929 mouse fibroblast was accelerated. L929 cells only took 3h to reach 100% cell adhesion on 90 s N2 plasma-treated surface, while there was less than 50% cell adhesion on the untreated Thai silk fibroin surface after 6h of culture. The cell adhesion results were in agreement with the cytoskeleton development. L929 F-actin was more evident on 90 s N2 plasma-treated surface than others. It could be concluded that a lower energy AC50Hz plasma system enhanced early L929 mouse fibroblast adhesion on Thai silk fibroin surface without any significant change in surface topography and bulk chemistry.

  9. Prokaryotic expression and antimicrobial mechanism of XPF-St7-derived α-helical peptides.

    Science.gov (United States)

    Yi, Tonghui; Huang, Yibing; Chen, Yuxin

    2015-01-01

    XPF-St7 (GLLSNVAGLLKQFAKGGVNAVLNPK) is an antimicrobial peptide isolated from Silurana tropicalis. We developed an α-helical segment of XPF-St7 termed as XPF2. Using the XPF2 as a framework, we increased the positive net charge of XPF2 by amino acid substitutions, and thus obtained two novel antimicrobial peptides XPF4 and XPF6. These were each fused with an ubiquitin tag and successfully expressed in Escherichia coli. This ubiquitin fusion system may present a viable alternative for industrial production of antimicrobial peptides. XPF4 and XPF6 showed much better overall antimicrobial activity against both Gram-negative and Gram-positive bacteria than XPF2. The therapeutic index of XPF4 and XPF6 was 5.6-fold and 6.7-fold of XPF2, respectively. Bacterial cell membrane permeabilization and genomic DNA interaction assays were utilized to explore the mechanism of action of XPF serial peptides. The results revealed that the target of these antimicrobial peptides was the bacterial cytoplasmic membrane. Copyright © 2014 European Peptide Society and John Wiley & Sons, Ltd.

  10. An NCAM-derived FGF-receptor agonist, the FGL-peptide, induces neurite outgrowth and neuronal survival in primary rat neurons

    DEFF Research Database (Denmark)

    Neiiendam, Johanne Louise; Køhler, Lene Boding; Christensen, Claus

    2004-01-01

    The Neural Cell Adhesion Molecule (NCAM) plays a crucial role in development of the central nervous system regulating cell migration, differentiation and synaptogenesis. NCAM mediates cell-cell adhesion through homophilic NCAM binding, subsequently resulting in activation of the fibroblast growth...

  11. High-affinity human leucocyte antigen class I binding variola-derived peptides induce CD4(+) T cell responses more than 30 years post-vaccinia virus vaccination

    DEFF Research Database (Denmark)

    Wang, M.; Tang, Sheila Tuyet; Lund, Ole;

    2009-01-01

    Interferon-gamma secreting T lymphocytes against pox virus-derived synthetic 9-mer peptides were tested by enzyme-linked immunospot in peripheral blood of individuals vaccinated with vaccinia virus more than 30 years ago. The peptides were characterized biochemically as high-affinity human...

  12. Cleavage specificity analysis of six type II transmembrane serine proteases (TTSPs using PICS with proteome-derived peptide libraries.

    Directory of Open Access Journals (Sweden)

    Olivier Barré

    Full Text Available BACKGROUND: Type II transmembrane serine proteases (TTSPs are a family of cell membrane tethered serine proteases with unclear roles as their cleavage site specificities and substrate degradomes have not been fully elucidated. Indeed just 52 cleavage sites are annotated in MEROPS, the database of proteases, their substrates and inhibitors. METHODOLOGY/PRINCIPAL FINDING: To profile the active site specificities of the TTSPs, we applied Proteomic Identification of protease Cleavage Sites (PICS. Human proteome-derived database searchable peptide libraries were assayed with six human TTSPs (matriptase, matriptase-2, matriptase-3, HAT, DESC and hepsin to simultaneously determine sequence preferences on the N-terminal non-prime (P and C-terminal prime (P' sides of the scissile bond. Prime-side cleavage products were isolated following biotinylation and identified by tandem mass spectrometry. The corresponding non-prime side sequences were derived from human proteome databases using bioinformatics. Sequencing of 2,405 individual cleaved peptides allowed for the development of the family consensus protease cleavage site specificity revealing a strong specificity for arginine in the P1 position and surprisingly a lysine in P1' position. TTSP cleavage between R↓K was confirmed using synthetic peptides. By parsing through known substrates and known structures of TTSP catalytic domains, and by modeling the remainder, structural explanations for this strong specificity were derived. CONCLUSIONS: Degradomics analysis of 2,405 cleavage sites revealed a similar and characteristic TTSP family specificity at the P1 and P1' positions for arginine and lysine in unfolded peptides. The prime side is important for cleavage specificity, thus making these proteases unusual within the tryptic-enzyme class that generally has overriding non-prime side specificity.

  13. Xenopus laevis neuronal cell adhesion molecule (nrcam): plasticity of a CAM in the developing nervous system.

    Science.gov (United States)

    Lokapally, Ashwin; Metikala, Sanjeeva; Hollemann, Thomas

    2017-01-01

    Neuron-glial-related cell adhesion molecule (NRCAM) is a neuronal cell adhesion molecule of the L1 immunoglobulin superfamily, which plays diverse roles during nervous system development including axon growth and guidance, synapse formation, and formation of the myelinated nerve. Perturbations in NRCAM function cause a wide variety of disorders, which can affect wiring and targeting of neurons, or cause psychiatric disorders as well as cancers through abnormal modulation of signaling events. In the present study, we characterize the Xenopus laevis homolog of nrcam. Expression of Xenopus nrcam is most abundant along the dorsal midline throughout the developing brain and in the outer nuclear layer of the retina.

  14. Cell adhesion to cathodic arc plasma deposited CrAlSiN thin films

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sun Kyu, E-mail: skim@ulsan.ac.kr [School of Materials Science and Engineering, University of Ulsan, Ulsan 680-749 (Korea, Republic of); Pham, Vuong-Hung [Department of Materials Science and Engineering, Seoul National University, Seoul 151-744 (Korea, Republic of); Kim, Chong-Hyun [Department of Food Science, Cornell University, Ithaca, NY 14853 (United States)

    2012-07-01

    Osteoblast cell response (cell adhesion, actin cytoskeleton and focal contact adhesion as well as cell proliferation) to CrN, CrAlSiN and Ti thin films was evaluated in vitro. Cell adhesion and actin stress fibers organization depended on the film composition significantly. Immunofluorescent staining of vinculin in osteoblast cells showed good focal contact adhesion on the CrAlSiN and Ti thin films but not on the CrN thin films. Cell proliferation was significantly greater on the CrAlSiN thin films as well as on Ti thin films than on the CrN thin films.

  15. Drosophila big brain does not act as a water channel, but mediates cell adhesion.

    Science.gov (United States)

    Tatsumi, Kimiko; Tsuji, Shoji; Miwa, Hideki; Morisaku, Toshinori; Nuriya, Mutsuo; Orihara, Minako; Kaneko, Kazunari; Okano, Hideyuki; Yasui, Masato

    2009-06-18

    The neurogenic gene Drosophila big brain (bib) has a high sequence homology to aquaporin-4. However, its cellular functions in Drosophila neurogenesis have remained elusive. Here we investigated cell adhesion, and the ion and water permeability of Bib. The adhesive function was examined by a cell aggregation assay using L cells. Bib-transfected L cells formed aggregated clusters, while control-L cells remained as a single cell suspension. Ion permeation was not confirmed in L cells stably expressing Bib. When expressed in COS7 cells, Bib exhibited limited water permeability. This newly found cell adhesive function of Bib may be important for Drosophila neurogenesis.

  16. Binding Strength Between Cell Adhesion Proteoglycans Measured by Atomic Force Microscopy

    Science.gov (United States)

    Dammer, Ulrich; Popescu, Octavian; Wagner, Peter; Anselmetti, Dario; Guntherodt, Hans-Joachim; Misevic, Gradimir N.

    1995-02-01

    Measurement of binding forces intrinsic to adhesion molecules is necessary to assess their contribution to the maintenance of the anatomical integrity of multicellular organisms. Atomic force microscopy was used to measure the binding strength between cell adhesion proteoglycans from a marine sponge. Under physiological conditions, the adhesive force between two cell adhesion molecules was found to be up to 400 piconewtons. Thus a single pair of molecules could hold the weight of 1600 cells. High intermolecular binding forces are likely to form the basis for the integrity of the multicellular sponge organism.

  17. Protein nanopore-based, single-molecule exploration of copper binding to an antimicrobial-derived, histidine-containing chimera peptide.

    Science.gov (United States)

    Mereuta, Loredana; Schiopu, Irina; Asandei, Alina; Park, Yoonkyung; Hahm, Kyung-Soo; Luchian, Tudor

    2012-12-11

    Metal ions binding exert a crucial influence upon the aggregation properties and stability of peptides, and the propensity of folding in various substates. Herein, we demonstrate the use of the α-HL protein as a powerful nanoscopic tool to probe Cu(2+)-triggered physicochemical changes of a 20 aminoacids long, antimicrobial-derived chimera peptide with a His residue as metal-binding site, and simultaneously dissect the kinetics of the free- and Cu(2+)-bound peptide interaction to the α-HL pore. Combining single-molecule electrophysiology on reconstituted lipid membranes and fluorescence spectroscopy, we show that the association rate constant between the α-HL pore and a Cu(2+)-free peptide is higher than that of a Cu(2+)-complexed peptide. We posit that mainly due to conformational changes induced by the bound Cu(2+) on the peptide, the resulting complex encounters a higher energy barrier toward its association with the protein pore, stemming most likely from an extra entropy cost needed to fit the Cu(2+)-complexed peptide within the α-HL lumen region. The lower dissociation rate constant of the Cu(2+)-complexed peptide from α-HL pore, as compared to that of Cu(2+)-free peptide, supports the existence of a deeper free energy well for the protein interaction with a Cu(2+)-complexed peptide, which may be indicative of specific Cu(2+)-mediated contributions to the binding of the Cu(2+)-complexed peptide within the pore lumen.

  18. A novel recombinant slow-release TNF α-derived peptide effectively inhibits tumor growth and angiogensis.

    Science.gov (United States)

    Ma, Yi; Zhao, Shaojun; Shen, Shutao; Fang, Shixiong; Ye, Zulu; Shi, Zhi; Hong, An

    2015-09-04

    RMP16, a recombinant TNF α-derived polypeptide comprising a specific human serum albumin (HSA)-binding 7-mer peptide identified by phage display screening (WQRPSSW), a cleavage peptide for Factor Xa (IEGR), and a 20-amino acid bioactive peptide P16 (TNF α segment including amino acid residues 75-94), was prepared by gene-engineering technology. RMP16 showed prolonged half-life, 13.11 hours in mice (half-lives of P16 and TNF α are 5.77 and 29.0 minutes, respectively), and obviously higher receptor selectivity for TNFRI than TNF α. RMP16 had significant inhibition effects for multiple tumor cells, especially prostate cancer Du145 cells, and human vascular endothelial cells but not for human mammary non-tumorigenic epithelial cells. RMP16 can more effectively induce apoptosis and inhibit proliferation for DU145 cells than P16 and TNF α via the caspase-dependent apoptosis pathway and G0/G1 cell cycle arrest. In nude mice with transplanted tumor of DU145 cells, RMP16 significantly induced apoptosis and necrosis of tumor tissues but causing less side effects, and tumor inhibitory rate reached nearly 80%, furthermore, RMP16 can potently inhibit tumor angiogenesis and neovascularization. These findings suggest that RMP16 may represent a promising long-lasting antitumor therapeutic peptide with less TNF α-induced toxicity.

  19. Simulations of the pore structures for a M2G1yR derived channel forming peptide in membrane

    Science.gov (United States)

    Al-Rawi, Ahlam N.; Al-Rawi, Asma; Chen, Jianhan; Herrera, Alvaro; Tomich, John; Rahman, Talat S.

    2008-03-01

    In an effort to develop a peptide-based compound suitable for clinical use as a channel replacement therapeutic for treating channelopathies such as cystic fibrosis, we present a reductionist model that appears to capture many of the biophysical properties of an intact ion channel using short channel-forming peptides. We have developed two anion selective channel-forming peptides with near native and altered properties from the peptides derived from the glycine receptor: NK4-M2GlyR-p22 WT (KKKKPAR-VGLGITTVLTMTTQS) and NK4-M2GlyR-p22 S22W (KKKKPARVGLGITTVLTMTTQW), respectively. Starting with the two structures determined by solution multidimensional NMR (800 MHz) in SDS, we used CHARMM and NAMD to perform molecular dynamics simulations on the monomers. Using the existing experimental data, we then built an initial 5- helix assembly by altering the tilted angle, rotational angle and pore radius. We investigated the impact of the single mutation at position 22 on the structure and dynamics of the pore formed in a membrane build in a hydrated POPC lipid bilayer. Probable structures for both assemblies are presented.

  20. Characterizing the role of cell-wall β-1,3-exoglucanase Xog1p in Candida albicans adhesion by the human antimicrobial peptide LL-37.

    Directory of Open Access Journals (Sweden)

    Pei-Wen Tsai

    Full Text Available Candida albicans is the major fungal pathogen of humans. Its adhesion to host-cell surfaces is the first critical step during mucosal infection. Antimicrobial peptides play important roles in the first line of mucosal immunity against C. albicans infection. LL-37 is the only member of the human cathelicidin antimicrobial peptide family and is commonly expressed in various tissues, including epithelium. We previously showed that LL-37 significantly reduced C. albicans adhesion to plastic, oral epidermoid OECM-1 cells, and urinary bladders of female BALB/c mice. The inhibitory effect of LL-37 on cell adhesion occurred via the binding of LL-37 to cell-wall carbohydrates. Here we showed that formation of LL-37-cell-wall protein complexes potentially inhibits C. albicans adhesion to polystyrene. Using phage display and ELISA, we identified 10 peptide sequences that could bind LL-37. A BLAST search revealed that four sequences in the major C. albicans cell-wall β-1,3-exoglucanase, Xog1p, were highly similar to the consensus sequence derived from the 10 biopanned peptides. One Xog1p-derived peptide, Xog1p(90-115, and recombinant Xog1p associated with LL-37, thereby reversing the inhibitory effect of LL-37 on C. albicans adhesion. LL-37 reduced Xog1p activity and thus interrupted cell-wall remodeling. Moreover, deletion of XOG1 or another β-1,3-exoglucanase-encoding gene EXG2 showed that only when XOG1 was deleted did cellular exoglucanase activity, cell adhesion and LL-37 binding decrease. Antibodies against Xog1p also decreased cell adhesion. These data reveal that Xog1p, originally identified from LL-37 binding, has a role in C. albicans adhesion to polystyrene and, by inference, attach to host cells via direct or indirect manners. Compounds that target Xog1p might find use as drugs that prevent C. albicans infection. Additionally, LL-37 could potentially be used to screen for other cell-wall components involved in fungal cell adhesion.

  1. Mechanisms of the antifungal action of marine metagenome-derived peptide, MMGP1, against Candida albicans.

    Directory of Open Access Journals (Sweden)

    Muthuirulan Pushpanathan

    Full Text Available BACKGROUND: Development of resistant variants to existing antifungal drugs continues to be the serious problem in Candida albicans-induced fungal pathogenesis, which has a considerable impact on animal and human health. Identification and characterization of newer drugs against C. albicans is, therefore, essential. MMGP1 is a direct cell-penetrating peptide recently identified from marine metagenome, which was found to possess potent antifungal activity against C. albicans. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we investigated the mechanism of antifungal action of MMGP1 against C. albicans. Agarose gel shift assay found the peptide to be having a remarkable DNA-binding ability. The modification of the absorption spectra and fluorescence quenching of the tryptophyl residue correspond to the stacking between indole ring and nucleotide bases. The formation of peptide-DNA complexes was confirmed by fluorescence quenching of SYTO 9 probe. The interaction of peptide with plasmid DNA afforded protection of DNA from enzymatic degradation by DNase I. In vitro transcription of mouse β-actin gene in the presence of peptide led to a decrease in the level of mRNA synthesis. The C. albicans treated with MMGP1 showed strong inhibition of biosynthetic incorporation of uridine analog 5-ethynyluridine (EU into nascent RNA, suggesting the peptide's role in the inhibition of macromolecular synthesis. Furthermore, the peptide also induces endogenous accumulation of reactive oxygen species (ROS in C. albicans. MMGP1 supplemented with glutathione showed an increased viability of C. albicans cells. The hyper-produced ROS by MMGP1 leads to increased levels of protein carbonyls and thiobarbituric acid reactive substances and it also causes dissipation of mitochondrial membrane potential and DNA fragmentation in C. albicans cells. CONCLUSION: And Significance: Therefore, the antifungal activity of MMGP1 could be attributed to its binding with DNA, causing

  2. Structure of a SARS coronavirus-derived peptide bound to the human major histocompatibility complex class I molecule HLA-B*1501

    DEFF Research Database (Denmark)

    Røder, Gustav; Kristensen, Ole; Kastrup, Jette S;

    2008-01-01

    , the crystal structure of HLA-B*1501 in complex with a SARS coronavirus-derived nonapeptide (VQQESSFVM) has been determined at high resolution (1.87 A). The peptide is deeply anchored in the B and F pockets, but with the Glu4 residue pointing away from the floor in the peptide-binding groove, making......The human leukocyte antigen (HLA) class I system comprises a highly polymorphic set of molecules that specifically bind and present peptides to cytotoxic T cells. HLA-B*1501 is a prototypical member of the HLA-B62 supertype and only two peptide-HLA-B*1501 structures have been determined. Here...

  3. T cell-mediated cytotoxicity against p53-protein derived peptides in bulk and limiting dilution cultures of healthy donors

    DEFF Research Database (Denmark)

    Röpke, M; Regner, M; Claesson, M H

    1995-01-01

    The p53 tumour suppressor gene product plays an important role in the development of most human cancers. Point mutations in the p53 gene are common in malignant states and results in over-expression of wild type and mutant determinants of the p53 protein. This process might generate MHC-I restric......The p53 tumour suppressor gene product plays an important role in the development of most human cancers. Point mutations in the p53 gene are common in malignant states and results in over-expression of wild type and mutant determinants of the p53 protein. This process might generate MHC......-I restricted epitopes for T cell recognition and p53-derived peptides have been suggested as targets for tumour-specific cytotoxic T lymphocytes (CTL). Our primary aim was to estimate the frequencies of p53-peptide reactive CTL precursors (CTLp) in peripheral blood from healthy young individuals. We selected...... wild type and mutated peptides derived from the p53 sequence with a binding motif for HLA-A2.1 molecules. Peripheral blood mononuclear cells (PBMC) from healthy HLA-A2 donors were stimulated in vitro in bulk cultures as well as in limiting dilution cultures using autologous cells pulsed with p53...

  4. Self-assembly of amphiphilic peptide (AF)6H5K15 derivatives: roles of hydrophilic and hydrophobic residues.

    Science.gov (United States)

    Thota, Naresh; Jiang, Jianwen

    2014-03-13

    A molecular dynamics simulation study is reported to investigate the roles of hydrophilic and hydrophobic residues in the self-assembly of (AF)6H5K15 peptide derivatives. The peptide, as well as water and counterions, are represented by the MARTINI coarse-grained model. The assembly is observed to follow a three-step process: formation of small clusters, large clusters, and micelles. With increasing length of hydrophilic Lys residues in (AF)6H5Kn (n = 10, 15, 20, and 25), assembly capability is found to be reduced with the formation of smaller micelles or the presence of individual peptide chains. Upon replacing Ala by more hydrophobic Phe in AmFnH5K15 (m + n = 12), larger micelles are formed. With increasing length of hydrophobic Phe residues in FnH5K15 (n = 4, 8, 12, and 16), micelle size increases and the morphology shifts from spherical to fiber-like. The simulation study provides mechanistic insight into the crucial roles of hydrophilicity and hydrophobicity in the assembly of (AF)6H5K15 derivatives; it reveals that assembly capability is reduced by increasing hydrophilicity, whereas increasing hydrophobicity leads to morphology transition.

  5. Simulations of the Pore Structures for a M2GlyR Derived Channel Forming Peptide in Different Membrane Environments

    Science.gov (United States)

    Al-Rawi, A.; Herrera, A.; Tomich, J.; Rahman, T.

    2007-03-01

    As part of an effort to develop a peptide-based compound suitable for clinical use as a channel replacement therapeutic for treating channelopathies such as cystic fibrosis, we present a reductionist model that appears to grasp the characteristics of ion channeling peptides. In particular we present the observed changes in the functional characteristics of NK4-M2GlyR p22 (KKKKPARVGLGITTVLTMTTQS), a M2 GlyR derived channel forming peptide. Starting with a structure determined by multidimensional NMR (800 MHz) in SDS, a potential from CHARMM force-field was used to relax the structure of NK4-M2GlyR p22. Following the relaxation, numerous pore structures were generated for the symmetric five-helix assembly with geometries varying from cylindrical to conical. As it is difficult a priori to assign accurately the orientation of the hydrophilic portion of M2GlyR derived amphipath towards the inside of the pore, we tilted and rotated the helical structure by five different angles about the backbone axis before forming the pore. Energy minimization of the channel was performed in vacuum, in phosphotidylcholine (POPC) membrane, and 60% POPC 30% phosphotidylethanolamine (POPE) in order to determine the effect of the environment surrounding on the structure on its energy minimization. We will present the various pore assemblies, in the different membrane environments, used to predict the most probably membrane bound structure.

  6. 皮肤抗菌肽的研究进展%Advances in skin-derived antimicrobial peptides

    Institute of Scientific and Technical Information of China (English)

    郑勇军; 夏照帆

    2013-01-01

    The antimicrobial peptides (AMP) are essential components of innate immunity.Human skin-derived antimicrobial peptides mainly include β-defensins and cathelicidins family and they are widely expressed in skin keratinocytes and inflammatory cells.Skin-derived antimicrobial peptides play important roles in skin,such as protecting skin from infection,regulating the immune response of skin,enhancing wound healing and angiogenesis.Their expressions are influenced by many factors in vivo and in vitro and closely related to various inflammatory diseases of skin.They may also play an important role in wound healing of diabetes.%抗菌肽是机体固有免疫的重要组成部分,人类皮肤抗菌肽主要包括cathelicidins家族和β-防御素家族,广泛表达于皮肤角质形成细胞及各种炎症细胞.皮肤抗菌肽除了直接杀菌作用外,还能调节免疫反应,促进伤口愈合和血管新生,其表达受到体内,体外多种因素的影响,与各种皮肤炎症性疾病发病密切相关,也可能在糖尿病创面愈合中发挥着重要作用.

  7. In vitro antihistamine-releasing activity of a peptide derived from wasp venom of Vespa orientalis

    Institute of Scientific and Technical Information of China (English)

    Jafar Jalaei; Mehdi Fazeli; Hamid Rajaian; Somayeh Layeghi Ghalehsoukhteh; Alireza Dehghani; Dominic Winter

    2016-01-01

    Objective: To investigate the antihistamine-releasing effect of a peptide isolated from wasp venom of Vespa orientalis.Methods: This peptide was separated from crude venom by chromatography methods and mass spectrometry. Then various concentrations(2, 4, 8, 16, 32, 64, 128 and256 mmol/L) of the peptide were incubated with mast cells and lactate dehydrogenase assay was performed.Results: No significant effect was observed in lactate dehydrogenase absorbance under128 mmol/L concentration. This implied that the peptide did not cause cell death in mast cells and consequently, histamine release did not happen. Moreover, the results showed the IC50 of mast cells degranulation at 126 mmol/L, which was approximately high implying that this peptide had high selectivity for normal cells and did not cause histamine release from these cells.Conclusions: This would be a great aim in new drug development, in which an agent acts potentially on its target tissue without activating the immune system.

  8. Milk proteins-derived bioactive peptides in dairy products: molecular, biological and methodological aspects

    Directory of Open Access Journals (Sweden)

    Bartłomiej Dziuba

    2014-03-01

    Full Text Available Proteins are one of the primary components of the food, both in terms of nutrition and function. They are main source of amino acids, essential for synthesis of proteins, and also source of energy. Additionally, many proteins exhibit specifi c biological activities, which may have effect on functional or pro-health properties of food products. These proteins and their hydrolysis products, peptides, may infl uence the properties of food and human organism. The number of commercially available food products containing bioactive peptides is very low, apart from that milk proteins are their rich source. It could be supposed that number of available products with declared activity will rise in near future because of observed strong uptrend on interest in such products. Molecular and biological properties of milk proteins, as precursors of bioactive peptides was characterised in the work. Therefore, the strategy of research and obtaining of such peptides both in laboratory and industrial scale, as well as the range of their commercial application, was presented. Several examples of research efforts presenting high potential to develop new products containing bioactive peptides from milk proteins and predetermined as nutraceuticals was described.

  9. Milk proteins-derived bioactive peptides in dairy products: molecular, biological and methodological aspects.

    Science.gov (United States)

    Dziuba, Bartłomiej; Dziuba, Marta

    2014-01-01

    Proteins are one of the primary components of the food, both in terms of nutrition and function. They are main source of amino acids, essential for synthesis of proteins, and also source of energy. Additionally, many proteins exhibit specific biological activities, which may have effect on functional or pro-health properties of food products. These proteins and their hydrolysis products, peptides, may influence the properties of food and human organism. The number of commercially available food products containing bioactive peptides is very low, apart from that milk proteins are their rich source. It could be supposed that number of available products with declared activity will rise in near future because of observed strong uptrend on interest in such products. Molecular and biological properties of milk proteins, as precursors of bioactive peptides was characterised in the work. Therefore, the strategy of research and obtaining of such peptides both in laboratory and industrial scale, as well as the range of their commercial application, was presented. Several examples of research efforts presenting high potential to develop new products containing bioactive peptides from milk proteins and predetermined as nutraceuticals was described.

  10. Effects of active immunisation with myelin basic protein and myelin-derived altered peptide ligand on pain hypersensitivity and neuroinflammation.

    Science.gov (United States)

    Perera, Chamini J; Lees, Justin G; Duffy, Samuel S; Makker, Preet G S; Fivelman, Brett; Apostolopoulos, Vasso; Moalem-Taylor, Gila

    2015-09-15

    Neuropathic pain is a debilitating condition in multiple sclerosis and experimental autoimmune encephalomyelitis (EAE). Specific myelin basic protein (MBP) peptides are encephalitogenic, and myelin-derived altered peptide ligands (APLs) are capable of preventing and ameliorating EAE. We investigated the effects of active immunisation with a weakly encephalitogenic epitope of MBP (MBP87-99) and its mutant APL (Cyclo-87-99[A(91),A(96)]MBP87-99) on pain hypersensitivity and neuroinflammation in Lewis rats. MBP-treated rats exhibited significant mechanical and thermal pain hypersensitivity associated with infiltration of T cells, MHC class II expression and microglia activation in the spinal cord, without developing clinical signs of paralysis. Co-immunisation with APL significantly decreased pain hypersensitivity and neuroinflammation emphasising the important role of neuroimmune crosstalk in neuropathic pain.

  11. Effects of different routes of administration on the immunogenicity of the Tat protein and a Tat-derived peptide.

    Science.gov (United States)

    Finessi, Valentina; Nicoli, Francesco; Gallerani, Eleonora; Sforza, Fabio; Sicurella, Mariaconcetta; Cafaro, Aurelio; Caputo, Antonella; Ensoli, Barbara; Gavioli, Riccardo

    2015-01-01

    The use of the Tat protein of HIV in vaccines against AIDS showed promising results in primate and human studies. To characterize the impact of the administration route on the induction of humoral responses at systemic and mucosal levels, we compared intradermal, intramuscular and mucosal immunizations with Tat and a Tat-derived peptide. Mice were immunized with the Tat protein by different routes and the titer and isotype of anti-Tat antibodies were assessed in serum and mucosal lavages. Intramuscular and intradermal administrations showed comparable immunogenicity, while the mucosal administration was unable to induce IgM in serum and IgG at mucosal sites but showed superior immunogenicity in terms of IgA induction. Anti-Tat antibodies were also obtained upon vaccination with the immunodominant Tat 1-20 peptide which was, however, less immunogenic than the whole Tat protein.

  12. NMR solution structure of the peptide fragment 1-30, derived from unprocessed mouse Doppel protein, in DHPC micelles.

    Science.gov (United States)

    Papadopoulos, Evangelos; Oglecka, Kamila; Mäler, Lena; Jarvet, Jüri; Wright, Peter E; Dyson, H Jane; Gräslund, Astrid

    2006-01-10

    The downstream prion-like Doppel (Dpl) protein is a homologue related to the prion protein (PrP). Dpl is expressed in the brains of mice that do not express PrP, and Dpl is known to be toxic to neurons. One mode of toxicity has been suggested to involve direct membrane interactions. PrP under certain conditions of cell trafficking retains an uncleaved signal peptide, which may also hold for the much less studied Dpl. For a peptide with a sequence derived from the N-terminal part (1-30) of mouse Dpl (mDpl(1-30)) CD spectroscopy shows about 40% alpha-helical structure in DHPC and SDS micelles. In aqueous solution it is mostly a random coil. The three-dimensional solution structure was determined by NMR for mDpl(1-30) associated with DHPC micelles. 2D 1H NMR spectra of the peptide in q = 0.25 DMPC/DHPC bicelles only showed signals from the unstructured termini, indicating that the structured part of the peptide resides within the lipid bilayer. Together with 2H2O exchange data in the DHPC micelle solvent, these results show an alpha-helix protected from solvent exchange between residues 7 and 19, and suggest that the alpha-helical segment can adopt a transmembrane localization also in a membrane. Leakage studies with entrapped calcein in large unilamellar phospholipid vesicles showed that the peptide is almost as membrane perturbing as melittin, known to form pores in membranes. The results suggest a possible channel formation mechanism for the unprocessed Dpl protein, which may be related to toxicity through direct cell membrane interaction and damage.

  13. Preparation and ectopic osteogenesis in vivo of scaffold based on mineralized recombinant human-like collagen loaded with synthetic BMP-2-derived peptide

    Energy Technology Data Exchange (ETDEWEB)

    Wu Bin; Zheng Qixin; Guo Xiaodong; Wu Yongchao [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China); Wang Yu; Cui Fuzai [Biomaterials Laboratory, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China)], E-mail: gxdwh@yahoo.com.cn

    2008-12-15

    The ideal bone graft material must be biocompatible, biodegradable, osteoconductive and osteoinductive. In this study, a new biomimetic scaffold based on mineralized recombinant collagen, nano-hydroxyapatite/recombinant human-like collagen/poly(lactic acid) (nHA/RHLC/PLA), was prepared and the synthetic P24 peptide derived from BMP-2 was introduced into the porous nHA/RHLC/PLA scaffold to improve its osteoinductive property. The nHA/RHLC/PLA implants loaded with 3 mg, 2 mg, 1 mg and 0 mg P24 peptide were implanted subcutaneously into rats. At the 4th, 8th and 12th weeks after implantation, the rats were sacrificed in batch and the samples were harvested. Their osteogenic capability was detected by CT scan and histological observation. The results indicated that the osteogenic capability of 3 mg, 2 mg and 1 mg of the P24 peptide was superior to the implants without the P24 peptide. There was no significant difference between implants with 3 mg and 2 mg P24 peptide, but the osteogenic capability of the two dosage groups was significantly better than that of the 1 mg group. It was concluded that BMP-2-derived peptide can increase the osteoinduction of nHA/RHLC/PLA scaffold and the P24 peptide induced new bone formation in a dose-dependent manner. The nHA/RHLC/PLA scaffold loaded with the synthetic BMP-2-derived peptide is a kind of ideal scaffold material for bone tissue engineering.

  14. Metabolism of Cryptic Peptides Derived from Neuropeptide FF Precursors: The Involvement of Insulin-Degrading Enzyme

    Directory of Open Access Journals (Sweden)

    Giuseppe Grasso

    2014-09-01

    Full Text Available The term “cryptome” refers to the subset of cryptic peptides with bioactivities that are often unpredictable and very different from the parent protein. These cryptic peptides are generated by proteolytic cleavage of proteases, whose identification in vivo can be very challenging. In this work, we show that insulin-degrading enzyme (IDE is able to degrade specific amino acid sequences present in the neuropeptide pro-NPFFA (NPFF precursor, generating some cryptic peptides that are also observed after incubation with rat brain cortex homogenate. The reported experimental findings support the increasingly accredited hypothesis, according to which, due to its wide substrate selectivity, IDE is involved in a wide variety of physiopathological processes.

  15. Dual host-defence functions of SPLUNC2/PSP and synthetic peptides derived from the protein.

    Science.gov (United States)

    Gorr, Sven-Ulrik; Abdolhosseini, Mahsa; Shelar, Anuradha; Sotsky, Julie

    2011-08-01

    PSP (parotid secretory protein)/SPLUNC2 (short palate, lung and nasal epithelium clone 2) is expressed in human salivary glands and saliva. The protein exists as an N-glycosylated and non-glycosylated form and both appear to induce agglutination of bacteria, a major antibacterial function for salivary proteins. Both forms of PSP/SPLUNC2 bind LPS (lipopolysaccharide), suggesting that the protein may also play an anti-inflammatory role. Based on the predicted structure of PSP/SPLUNC2 and the location of known antibacterial and anti-inflammatory peptides in BPI (bactericidal/permeability-increasing protein) and LBP (LPS-binding protein), we designed GL13NH2 and GL13K, synthetic peptides that capture these proposed functions of PSP/SPLUNC2. GL13NH3 agglutinates bacteria, leading to increased clearance by macrophages and reduced spread of infection in a plant model. GL13K kills bacteria with a minimal inhibitory concentration of 5-10 μg/ml, kills bacteria in biofilm and retains activity in 150 mM NaCl and 50% saliva. Both peptides block endotoxin action, but only GL13K appears to bind endotoxin. The peptides do not cause haemolysis, haemagglutination in serum, inhibit mammalian cell proliferation or induce an inflammatory response in macrophages. These results suggest that the GL13NH2 and the modified peptide GL13K capture the biological activity of PSP/SPLUNC2 and can serve as lead compounds for the development of novel antimicrobial and anti-inflammatory peptides.

  16. Mitochondrial-derived N-formyl peptides: novel links between trauma, vascular collapse and sepsis.

    Science.gov (United States)

    Wenceslau, C F; McCarthy, C G; Goulopoulou, S; Szasz, T; NeSmith, E G; Webb, R C

    2013-10-01

    Sepsis is a major cause of mortality and morbidity in trauma patients despite aggressive treatment. Traumatic injury may trigger infective or non-infective systemic inflammatory response syndrome (SIRS) and sepsis. Sepsis and SIRS are accompanied by an inability to regulate the inflammatory response but the cause of this perturbation is still unknown. The major pathophysiological characteristic of sepsis is the vascular collapse (i.e., loss of control of vascular tone); however, at the cellular level the final mediator of extreme vasodilatation has yet to be identified. After trauma, cellular injury releases endogenous damage-associated molecular patterns (DAMPs) that activate the innate immune system. Mitochondrial DAMPs express at least two molecular signatures, N-formyl peptides and mitochondrial DNA that act on formyl peptide receptors (FPRs) and Toll-like receptor 9, respectively. N-Formyl peptides are potent immunocyte activators and, once released in the circulation, they induce modulation of vascular tone by cellular mechanisms that are not completely understood. We have observed that N-formyl peptides from bacterial (FMLP) and mitochondrial (FMIT) sources induce FPR-mediated vasodilatation in resistance arteries. Accordingly, we propose that tissue and cellular trauma induces the release of N-formyl peptides from mitochondria triggering inflammation and vascular collapse via activation of FPR and contributing to the development of sepsis. The proposed hypothesis provides clinically significant information linking trauma, mitochondrial N-formyl peptides and inflammation to vascular collapse and sepsis. If our hypothesis is true, it may lead to new strategies in the management of sepsis that can help clinicians effectively manage non-infectious and infectious inflammatory responses. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Reference intervals for C-peptide and insulin derived from a general adult Danish population.

    Science.gov (United States)

    Larsen, Pia Bükmann; Linneberg, Allan; Hansen, Torben; Friis-Hansen, Lennart

    2017-05-01

    Despite international efforts to standardize C-peptide and insulin calibrators and immunoassays, platform dependent differences still exist, and platform specific reference intervals are hence needed for correct interpretation. We therefore wanted to establish traceable reference intervals for C-peptide and insulin. In 623 consecutively recruited participants, insulin and C-peptide were measured using the Cobas e411 (Roche Diagnostics, Switzerland). Participants with diabetes were excluded (fasting Glucose ≥7.0mmol/L or HbA1c≥6.5%/≥48mmol/L) and reference intervals were calculated with and without the inclusion of persons who were prediabetic, according to two definitions (The World Health Organization (WHO) and American Diabetes Association (ADA)). To ensure the correctness of calibration, the control pools were analyzed by a reference laboratory. The reference intervals were calculated according to the IFCC guidelines, using the RefVal software (Solberg, Oslo, Norway). Comparison of our results with those from the reference laboratory revealed equivalence for C-peptide results whereas the insulin determined on the Cobas e411 assay were 15-20% higher. The difference is attributed to an incorrect conversion factor for converting from activity to metric units. The Cobas e411 assay uses the factor 6.945 for converting from U/mL to pmol/L. This is in disagreement with the biological activity of insulin which is 166.8×10(6)IU/mol or 6.00nmol/IU. We successfully established reference intervals for C-peptide and insulin for non-diabetic and prediabetic participants. The reference intervals for fasting C-peptide and fasting insulin are ready for implementation. A recertification of the insulin standards is needed. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  18. Synthetic Peptides Derived from Bovine Lactoferricin Exhibit Antimicrobial Activity against E. coli ATCC 11775, S. maltophilia ATCC 13636 and S. enteritidis ATCC 13076

    Directory of Open Access Journals (Sweden)

    Nataly De Jesús Huertas Méndez

    2017-03-01

    Full Text Available Linear, dimeric, tetrameric, and cyclic peptides derived from lactoferricin B–containing non-natural amino acids and the RWQWR motif were synthesized, purified, and characterized using RP-HPLC, MALDI-TOF mass spectrometry, and circular dichroism. The antibacterial activity of peptides against Escherichia coli ATCC 11775, Stenotrophomonas maltophilia ATCC 13636, and Salmonella enteritidis ATCC 13076 was evaluated. The minimum inhibitory concentration (MIC and minimum bactericidal concentration (MBC were determined. The synthetic bovine lactoferricin exhibited antibacterial activity against E. coli ATCC 11775 and S. enteritidis ATCC 13076. The dimeric peptide (RRWQWR2K-Ahx exhibited the highest antibacterial activity against the tested bacterial strain. The monomeric, cyclic, tetrameric, and palindromic peptides containing the RWQWR motif exhibited high and specific activity against E. coli ATCC 11775. The results suggest that short peptides derived from lactoferricin B could be considered as potential candidates for the development of antibacterial agents against infections caused by E. coli.

  19. Cell division orientation is coupled to cell-cell adhesion by the E-cadherin/LGN complex

    NARCIS (Netherlands)

    Gloerich, Martijn; Bianchini, Julie M.; Siemers, Kathleen A.; Cohen, Daniel J.; Nelson, W. James

    2017-01-01

    Both cell-cell adhesion and oriented cell division play prominent roles in establishing tissue architecture, but it is unclear how they might be coordinated. Here, we demonstrate that the cell-cell adhesion protein E-cadherin functions as an instructive cue for cell division orientation. This is

  20. High expression of carcinoembryonic antigen-related cell adhesion molecule (CEACAM) 6 and 8 in primary myelofibrosis

    DEFF Research Database (Denmark)

    Hasselbalch, Hans Carl; Skov, Vibe; Larsen, Thomas Stauffer;

    2011-01-01

    for the egress of CD34+ cells from the bone marrow. Carcinoembryonic antigen-related cell adhesion molecule (CEACAM) 6 has been implicated in cell adhesion, cellular invasiveness, angiogenesis, and inflammation, which are all key processes in the pathophysiology of PMF. Accordingly, CEACAMs may play an important...

  1. Cloning and sequencing of a DNA fragment encoding N37 apoptotic peptide derived from p53

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Objective It was reported that p53 apoptotic peptide (N37) could inhibit p73 gene through being bound with iASPP,which could induce tumor cell apoptosis. To further explore the function of N37,we constructed the cloning plasmid of DNA fragment encoding p53 (N37) apoptotic peptide by using DNA synthesis and molecular biology methods. Methods According to human p53 sequence from the GenBank database,the primer of p53(N37) gene was designed using Primer V7.0 software. The DNA fragment encoding p53 (N37) apopto...

  2. Proposal for novel curcumin derivatives as potent inhibitors against Alzheimer's disease: Ab initio molecular simulations on the specific interactions between amyloid-beta peptide and curcumin

    Science.gov (United States)

    Ota, Shintaro; Fujimori, Mitsuki; Ishimura, Hiromi; Shulga, Sergiy; Kurita, Noriyuki

    2017-10-01

    Accumulation of amyloid-β (Aβ) peptides in a brain is closely related with the pathogenesis of Alzheimer's disease. To suppress the production of Aβ peptides, we propose novel curcumin derivatives and investigate their binding properties with the amyloid precursor protein (APP), using protein-ligand docking as well as ab initio molecular simulations. Our proposed derivative (curcumin XIV) is found to have a large binding energy with APP and interacts strongly with the cleavage site Ala19 by secretase. It is thus expected that curcumin XIV can protect APP from the secretase attack and be a potent inhibitor against the production of Aβ peptides.

  3. Structural Mechanism Underpinning Cross-reactivity of a CD8+ T-cell Clone That Recognizes a Peptide Derived from Human Telomerase Reverse Transcriptase*

    Science.gov (United States)

    Cole, David K.; van den Berg, Hugo A.; Lloyd, Angharad; Crowther, Michael D.; Beck, Konrad; Ekeruche-Makinde, Julia; Miles, John J.; Bulek, Anna M.; Dolton, Garry; Schauenburg, Andrea J.; Wall, Aaron; Fuller, Anna; Clement, Mathew; Laugel, Bruno; Rizkallah, Pierre J.; Wooldridge, Linda; Sewell, Andrew K.

    2017-01-01

    T-cell cross-reactivity is essential for effective immune surveillance but has also been implicated as a pathway to autoimmunity. Previous studies have demonstrated that T-cell receptors (TCRs) that focus on a minimal motif within the peptide are able to facilitate a high level of T-cell cross-reactivity. However, the structural database shows that most TCRs exhibit less focused antigen binding involving contact with more peptide residues. To further explore the structural features that allow the clonally expressed TCR to functionally engage with multiple peptide-major histocompatibility complexes (pMHCs), we examined the ILA1 CD8+ T-cell clone that responds to a peptide sequence derived from human telomerase reverse transcriptase. The ILA1 TCR contacted its pMHC with a broad peptide binding footprint encompassing spatially distant peptide residues. Despite the lack of focused TCR-peptide binding, the ILA1 T-cell clone was still cross-reactive. Overall, the TCR-peptide contacts apparent in the structure correlated well with the level of degeneracy at different peptide positions. Thus, the ILA1 TCR was less tolerant of changes at peptide residues that were at, or adjacent to, key contact sites. This study provides new insights into the molecular mechanisms that control T-cell cross-reactivity with important implications for pathogen surveillance, autoimmunity, and transplant rejection. PMID:27903649

  4. Controlling the cell adhesion property of silk films by graft polymerization.

    Science.gov (United States)

    Dhyani, Vartika; Singh, Neetu

    2014-04-09

    We report here a graft polymerization method to improve the cell adhesion property of Bombyx mori silk fibroin films. B. mori silk has evolved as a promising material for tissue engineering because of its biocompatibility and biodegradability. However, silk's hydrophobic character makes cell adhesion and proliferation difficult. Also, the lack of sufficient reactive amino acid residues makes biofunctionalization via chemical modification challenging. Our study describes a simple method that provides increased chemical handles for tuning of the surface chemistry of regenerated silk films (SFs), thus allowing manipulation of their bioactivity. By grafting pAAc and pHEMA via plasma etching, we have increased carboxylic acid and hydroxyl groups on silk, respectively. These modifications allowed us to tune the hydrophilicity of SFs and provide functional groups for bioconjugation. Our strategy also allowed us to develop silk-based surface coatings, where spatial control over cell adhesion can be achieved. This control over cell adhesion in a particular region of the SFs is difficult to obtain via existing methods of modifying the silk fibroin instead of the SF surface. Thus, our strategy will be a valuable addition to the toolkit of biofunctionalization for enhancing SFs' tissue engineering applications.

  5. New serum markers for small-cell lung cancer. II. The neural cell adhesion molecule, NCAM

    DEFF Research Database (Denmark)

    Vangsted, A; Drivsholm, L; Andersen, E;

    1994-01-01

    The neural cell adhesion molecule (NCAM) was recently suggested as a marker for small-cell lung cancer (SCLC). Immunohistochemical analysis demonstrated the presence of the NCAM in 78% of SCLC patients and in 25% of patients with other cancer forms. NCAM was proposed to be the most sensitive marker...

  6. The Role of Immunoglobulin Superfamily Cell Adhesion Molecules in Cancer Metastasis

    Directory of Open Access Journals (Sweden)

    Chee Wai Wong

    2012-01-01

    Full Text Available Metastasis is a major clinical problem and results in a poor prognosis for most cancers. The metastatic pathway describes the process by which cancer cells give rise to a metastatic lesion in a new tissue or organ. It consists of interconnecting steps all of which must be successfully completed to result in a metastasis. Cell-cell adhesion is a key aspect of many of these steps. Adhesion molecules belonging to the immunoglobulin superfamily (Ig-SF commonly play a central role in cell-cell adhesion, and a number of these molecules have been associated with cancer progression and a metastatic phenotype. Surprisingly, the contribution of Ig-SF members to metastasis has not received the attention afforded other cell adhesion molecules (CAMs such as the integrins. Here we examine the steps in the metastatic pathway focusing on how the Ig-SF members, melanoma cell adhesion molecule (MCAM, L1CAM, neural CAM (NCAM, leukocyte CAM (ALCAM, intercellular CAM-1 (ICAM-1 and platelet endothelial CAM-1 (PECAM-1 could play a role. Although much remains to be understood, this review aims to raise the profile of Ig-SF members in metastasis formation and prompt further research that could lead to useful clinical outcomes.

  7. The neural cell adhesion molecule binds to fibroblast growth factor receptor 2

    DEFF Research Database (Denmark)

    Christensen, Claus; Lauridsen, Jes B; Berezin, Vladimir;

    2006-01-01

    The neural cell adhesion molecule (NCAM) can bind to and activate fibroblast growth factor receptor 1 (FGFR1). However, there are four major FGFR isoforms (FGFR1-FGFR4), and it is not known whether NCAM also interacts directly with the other three FGFR isoforms. In this study, we show by surface...

  8. Activated leukocyte cell adhesion molecule expression predicts lymph node metastasis in oral squamous cell carcinoma.

    NARCIS (Netherlands)

    Brand, M. van den; Takes, R.P.; Blokpoel-deRuyter, M.; Slootweg, P.J.; Kempen, L.C.L.T. van

    2010-01-01

    Lymphatic metastasis of oral squamous cell carcinoma (SCC) is important for prognosis and clinical decision making concerning the treatment of the neck but may be difficult to detect. Activated leukocyte cell adhesion molecule (ALCAM), has been shown to correlate with prognosis or tumor grade in dif

  9. Inhibition of neuronal cell–cell adhesion measured by the microscopic aggregation assay and impedance sensing

    NARCIS (Netherlands)

    Wiertz, Remy; Marani, Enrico; Rutten, Wim

    2010-01-01

    Microscopic aggregation assay and impedance sensing (IS) were used to monitor a change in in vitro neuron–neuron adhesion in response to blocking of cell adhesion molecules. By blocking neuron–neuron adhesion, migration and aggregation of neuronal cells can be inhibited. This leads to better control

  10. Degradable polyethylenimine derivate coupled to a bifunctional peptide R13 as a new gene-delivery vector

    Directory of Open Access Journals (Sweden)

    Liu K

    2012-02-01

    Full Text Available Kehai Liu1,2,*, Xiaoyu Wang1,*, Wei Fan1, Qing Zhu2, Jingya Yang2, Jing Gao3, Shen Gao1 1Department of Pharmaceutics, Shanghai Hospital, Second Military Medical University, 2Department of Biopharmaceutics, School of Food Science and Technology, Shanghai Ocean University, 3Department of Pharmaceutics, School of Pharmacy, Second Military Medical University, Shanghai, People's Republic of China*The first two authors contributed equally to this workBackground: To solve the efficiency versus cytotoxicity and tumor-targeting problems of polyethylenimine (PEI used as a nonviral gene delivery vector, a degradable PEI derivate coupled to a bifunctional peptide R13 was developed.Methods: First, we synthesized a degradable PEI derivate by crosslinking low-molecular-weight PEI with pluronic P123, then used tumor-targeting peptide arginine-glycine-aspartate-cysteine (RGDC, in conjunction with the cell-penetrating peptide Tat (49–57, to yield a bifunctional peptide RGDC-Tat (49–57 named R13, which can improve cell selection and increase cellular uptake, and, lastly, adopted R13 to modify the PEI derivates so as to prepare a new polymeric gene vector (P123-PEI-R13. The new gene vector was characterized in terms of its chemical structure and biophysical parameters. We also investigated the specificity, cytotoxicity, and gene transfection efficiency of this vector in avß3-positive human cervical carcinoma Hela cells and murine melanoma B16 cells in vitro.Results: The vector showed controlled degradation, strong targeting specificity to avß3 receptor, and noncytotoxicity in Hela cells and B16 cells at higher doses, in contrast to PEI 25 KDa. The particle size of P123-PEI-R13/DNA complexes was around 100–250 nm, with proper zeta potential. The nanoparticles can protect plasmid DNA from being digested by DNase I at a concentration of 6 U DNase I/µg DNA. The nanoparticles were resistant to dissociation induced by 50% fetal bovine serum and 600 µg/mL sodium

  11. Endoglin regulates mural cell adhesion in the circulatory system.

    Science.gov (United States)

    Rossi, Elisa; Smadja, David M; Boscolo, Elisa; Langa, Carmen; Arevalo, Miguel A; Pericacho, Miguel; Gamella-Pozuelo, Luis; Kauskot, Alexandre; Botella, Luisa M; Gaussem, Pascale; Bischoff, Joyce; Lopez-Novoa, José M; Bernabeu, Carmelo

    2016-04-01

    The circulatory system is walled off by different cell types, including vascular mural cells and podocytes. The interaction and interplay between endothelial cells (ECs) and mural cells, such as vascular smooth muscle cells or pericytes, play a pivotal role in vascular biology. Endoglin is an RGD-containing counter-receptor for β1 integrins and is highly expressed by ECs during angiogenesis. We find that the adhesion between vascular ECs and mural cells is enhanced by integrin activators and inhibited upon suppression of membrane endoglin or β1-integrin, as well as by addition of soluble endoglin (SolEng), anti-integrin α5β1 antibody or an RGD peptide. Analysis of different endoglin mutants, allowed the mapping of the endoglin RGD motif as involved in the adhesion process. In Eng (+/-) mice, a model for hereditary hemorrhagic telangectasia type 1, endoglin haploinsufficiency induces a pericyte-dependent increase in vascular permeability. Also, transgenic mice overexpressing SolEng, an animal model for preeclampsia, show podocyturia, suggesting that SolEng is responsible for podocytes detachment from glomerular capillaries. These results suggest a critical role for endoglin in integrin-mediated adhesion of mural cells and provide a better understanding on the mechanisms of vessel maturation in normal physiology as well as in pathologies such as preeclampsia or hereditary hemorrhagic telangiectasia.

  12. Surface characteristics and cell adhesion: a comparative study of four commercial dental implants.

    Science.gov (United States)

    Liu, Ruohong; Lei, Tianhua; Dusevich, Vladimir; Yao, Xiamei; Liu, Ying; Walker, Mary P; Wang, Yong; Ye, Ling

    2013-12-01

    The aims of this study were to compare surface properties of four commercial dental implants and to compare those implant systems' cell adhesion, which may be affected by the surface properties, and to provide scientific information on the selection of implants for clinicians. The surface properties of four commonly used dental implants (3i Nanotite™, Astra OsseoSpeed™, Nobel Biocare TiUnite®, and Straumann SLActive®) were studied using MicroSpy profiler, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy, and Raman microspectroscopy. Primary mouse alveolar bone cells were cultured on the surface of implants from the four companies. After 48-hour culture, SEM in combination with a quantitative analysis of SEM images was used to examine the cell adhesion. Cell adhesion rates (ratios of cell surface to implant surface) among different systems were compared. Distinct differences were found among these implants. Comparisons of roughness among three locations: flank, top, and valley within the same implant system, or in the same location among different implants were made. Generally Astra and Straumann systems showed the roughest surface, whereas 3i showed the smoothest surface. Multiple cracks were found on the surface of the Nobel Biocare system, which also had a dramatically lower level of titanium. In addition, rutile phase of titanium oxide was found in 3i, Astra, and Straumann systems, and anatase phase of titanium oxide was only detected in the Nobel Biocare system. After 48-hour culture, Astra and Straumann systems displayed the highest cell adhesion at the areas of flank, top, and valley of the implant surface. Primary cells also reached confluence on the valley, but significantly less in the 3i system. Nobel Biocare showed the least cell adhesion on the flank and valley. Implant systems have distinct differences in surface properties, leading to different cell adhesion results. Further in vivo study is needed to study the impact of

  13. Identification of NCAM-binding peptides promoting neurite outgrowth via a heterotrimeric G-protein-coupled pathway

    DEFF Research Database (Denmark)

    Hansen, Raino Kristian; Christensen, Claus; Korshunova, Irina;

    2007-01-01

    A combinatorial library of undecapeptides was produced and utilized for the isolation of peptide binding to the fibronectin type 3 modules (F3I-F3II) of the neural cell adhesion molecule (NCAM). The isolated peptides were sequenced and produced as dendrimers. Two of the peptides (denoted ENFIN2 a...

  14. MALDI-based identification of stable hazelnut protein derived tryptic marker peptides.

    Science.gov (United States)

    Cucu, T; De Meulenaer, B; Devreese, B

    2012-01-01

    Food allergy is an important health problem especially in industrialised countries. Tree nuts, among which are hazelnuts (Corylus avellana), are typically causing serious and life-threatening symptoms in sensitive subjects. Hazelnut is used as a food ingredient in pastry, confectionary products, ice cream and meat products, therefore undeclared hazelnut can be often present as a cross-contaminant representing a threat for allergic consumers. Mass spectrometric techniques are used for the detection of food allergens in processed foods, but limited information regarding stable tryptic peptide markers for hazelnut is available. The aim of this study was to detect stable peptide markers from modified hazelnut protein through the Maillard reaction and oxidation in a buffered solution. Peptides ³⁹⁵Gly-Arg⁴⁰³ from Cor a 11 and ²⁰⁹Gln-Arg²¹⁷, ³⁵¹Ile-Arg³⁶³, ⁴⁶⁴Ala-Arg⁴⁷⁸ and ⁴⁰¹Val-Arg⁴¹⁷ from Cor a 9 hazelnut allergens proved to be the most stable and could be detected and confirmed with high scores in most of the modified samples. The identified peptides can be further used as analytical targets for the development of more robust quantitative methods for hazelnut detection in processed foods.

  15. Characterization of Protein and Peptide Binding to Nanogels Formed by Differently Charged Chitosan Derivatives

    Directory of Open Access Journals (Sweden)

    Anastasia Zubareva

    2013-07-01

    Full Text Available Chitosan (Chi is a natural biodegradable cationic polymer with remarkable potency as a vehicle for drug or vaccine delivery. Chi possesses multiple groups, which can be used both for Chi derivatization and for particle formation. The aim of this work was to produce stable nanosized range Chi gels (nanogels, NGs with different charge and to study the driving forces of complex formation between Chi NGs and proteins or peptides. Positively charged NGs of 150 nm in diameter were prepared from hexanoyl chitosan (HC by the ionotropic gelation method while negatively charged NGs of 190 nm were obtained from succinoyl Chi (SC by a Ca2+ coacervation approach. NGs were loaded with a panel of proteins or peptides with different weights and charges. We show that NGs preferentially formed complexes with oppositely charged molecules, especially peptides, as was demonstrated by gel-electrophoresis, confocal microscopy and HPLC. Complex formation was accompanied by a change in zeta-potential and decrease in size. We concluded that complex formation between Chi NGs and peptide/proteins is mediated mostly by electrostatic interactions.

  16. A PCNA-derived cell permeable peptide selectively inhibits neuroblastoma cell growth.

    Directory of Open Access Journals (Sweden)

    Long Gu

    Full Text Available Proliferating cell nuclear antigen (PCNA, through its interaction with various proteins involved in DNA synthesis, cell cycle regulation, and DNA repair, plays a central role in maintaining genome stability. We previously reported a novel cancer associated PCNA isoform (dubbed caPCNA, which was significantly expressed in a broad range of cancer cells and tumor tissues, but not in non-malignant cells. We found that the caPCNA-specific antigenic site lies between L126 and Y133, a region within the interconnector domain of PCNA that is known to be a major binding site for many of PCNA's interacting proteins. We hypothesized that therapeutic agents targeting protein-protein interactions mediated through this region may confer differential toxicity to normal and malignant cells. To test this hypothesis, we designed a cell permeable peptide containing the PCNA L126-Y133 sequence. Here, we report that this peptide selectively kills human neuroblastoma cells, especially those with MYCN gene amplification, with much less toxicity to non-malignant human cells. Mechanistically, the peptide is able to block PCNA interactions in cancer cells. It interferes with DNA synthesis and homologous recombination-mediated double-stranded DNA break repair, resulting in S-phase arrest, accumulation of DNA damage, and enhanced sensitivity to cisplatin. These results demonstrate conceptually the utility of this peptide for treating neuroblastomas, particularly, the unfavorable MYCN-amplified tumors.

  17. Surface force measurements and simulations of mussel-derived peptide adhesives on wet organic surfaces.

    Science.gov (United States)

    Levine, Zachary A; Rapp, Michael V; Wei, Wei; Mullen, Ryan Gotchy; Wu, Chun; Zerze, Gül H; Mittal, Jeetain; Waite, J Herbert; Israelachvili, Jacob N; Shea, Joan-Emma

    2016-04-19

    Translating sticky biological molecules-such as mussel foot proteins (MFPs)-into synthetic, cost-effective underwater adhesives with adjustable nano- and macroscale characteristics requires an intimate understanding of the glue's molecular interactions. To help facilitate the next generation of aqueous adhesives, we performed a combination of surface forces apparatus (SFA) measurements and replica-exchange molecular dynamics (REMD) simulations on a synthetic, easy to prepare, Dopa-containing peptide (MFP-3s peptide), which adheres to organic surfaces just as effectively as its wild-type protein analog. Experiments and simulations both show significant differences in peptide adsorption on CH3-terminated (hydrophobic) and OH-terminated (hydrophilic) self-assembled monolayers (SAMs), where adsorption is strongest on hydrophobic SAMs because of orientationally specific interactions with Dopa. Additional umbrella-sampling simulations yield free-energy profiles that quantitatively agree with SFA measurements and are used to extract the adhesive properties of individual amino acids within the context of MFP-3s peptide adhesion, revealing a delicate balance between van der Waals, hydrophobic, and electrostatic forces.

  18. Combined exposure to betalactoglobulin-derived tolerogenic peptides and synbiotics alleviates food allergy response in vivo

    NARCIS (Netherlands)

    Kostadinova, A.; Van Esch, B.C.; Garssen, J.; Willemsen, L.E.M.; Knippels, L.M.J.

    2015-01-01

    Background: At-risk infants can be prevented from developing food allergy symptoms by feeding them hypoallergenic formulas containing cow's milk protein hydrolysates. This preventive effect might be a result of oral tolerance induction by immunogenic peptide fractions in the hydrolysates. Early expo

  19. Central Cell-Derived Peptides Regulate Early Embryo Patterning in Flowering Plants

    NARCIS (Netherlands)

    Costa, L.M.; Marshall, E.; Tesfaye, M.; Silverstein, K.A.T.; Mori, M.; Umetsu, Y.; Otterbach, S.L.; Papareddy, R.; Dickinson, H.G.; Boutilier, K.A.; VandenBosch, K.A.; Ohki, S.; Gutierrez-Marcos, J.F.

    2014-01-01

    Plant embryogenesis initiates with the establishment of an apical-basal axis; however, the molecular mechanisms accompanying this early event remain unclear. Here, we show that a small cysteine-rich peptide family is required for formation of the zygotic basal cell lineage and proembryo patterning i

  20. Viral replication modulated by synthetic peptide derived from hepatitis B virus X protein

    Institute of Scientific and Technical Information of China (English)

    Chang-Zheng Song; Qing-Wei Wang; Chang-Cheng Song; Zeng-Liang Bai

    2004-01-01

    AIM: A strategy for viral vaccine design is the use of conserved peptides to overcome the problem of sequence diversity. At present it is still unclear whether conserved peptide is safe as a candidate vaccine. We reported it here for the first time not only to highlight the biohazard issue and safety importance for viral peptide vaccine, but also to explore the effect of a fully conserved peptide on HBV replication within the carboxyl terminus of HBx.METHODS: We synthesized the fully conserved peptide (CP)with nine residues, FVLGGCRHK. HBV-producing 2.2.15 cells were treated with or without 3.5 μM CP for 36 hours.Quantitative detection of viral DNA was performed by realtime PCR. HBV antigens were determined by enzyme-linked immunoadsorbent assay (ELISA). Quantitative analyses of p53 and Bax proteins were based on immunofluorescence.Flow cytometry was performed to detect cell cycle and apoptosis.RESULTS: Both extracellular and intracellular copies of HBV DNA per ml were significantly increased atter incubation with 3.5 μM of CP. HBsAg and HBeAg in the cultured medium of CP-treatment cells were as abundant as untreated control cells. CP infiuenced negatively the extracellular viral gene products, and 3.5 μM CP could significantly inhibit intracellular HBsAg expression. In response to CP, intracellular HBeAg displayed an opposite pattern to that of HBsAg, and 3.5 μM CP could efficiently increase the level of intracellular HBeAg.Flow cytometric analyses exhibited no significant changes on cell cycle, apoptosis, p53 and Bax proteins in 2.2.15 cells with or without CP.CONCLUSION: Together with the resulte generated from the synthetic peptide, we address that the conserved region,a domain of HBx, may be responsible for modulating HBV replication. As conserved peptides from infectious microbes are used as immunogens to elicit immune responses, their latent biological hazard for human beings should be evaluated.

  1. Laminin active peptide/agarose matrices as multifunctional biomaterials for tissue engineering.

    Science.gov (United States)

    Yamada, Yuji; Hozumi, Kentaro; Aso, Akihiro; Hotta, Atsushi; Toma, Kazunori; Katagiri, Fumihiko; Kikkawa, Yamato; Nomizu, Motoyoshi

    2012-06-01

    Cell adhesive peptides derived from extracellular matrix components are potential candidates to afford bio-adhesiveness to cell culture scaffolds for tissue engineering. Previously, we covalently conjugated bioactive laminin peptides to polysaccharides, such as chitosan and alginate, and demonstrated their advantages as biomaterials. Here, we prepared functional polysaccharide matrices by mixing laminin active peptides and agarose gel. Several laminin peptide/agarose matrices showed cell attachment activity. In particular, peptide AG73 (RKRLQVQLSIRT)/agarose matrices promoted strong cell attachment and the cell behavior depended on the stiffness of agarose matrices. Fibroblasts formed spheroid structures on the soft AG73/agarose matrices while the cells formed a monolayer with elongated morphologies on the stiff matrices. On the stiff AG73/agarose matrices, neuronal cells extended neuritic processes and endothelial cells formed capillary-like networks. In addition, salivary gland cells formed acini-like structures on the soft matrices. These results suggest that the peptide/agarose matrices are useful for both two- and three-dimensional cell culture systems as a multifunctional biomaterial for tissue engineering.

  2. Aging effects of plasma polymerized ethylenediamine (PPEDA) thin films on cell-adhesive implant coatings

    Energy Technology Data Exchange (ETDEWEB)

    Testrich, H., E-mail: holger.testrich@uni-greifswald.de [University of Greifswald, Institute of Physics, Felix-Hausdorff Str. 6, 17489 Greifswald (Germany); Rebl, H. [University of Rostock, Biomedical Research Center, Department of Cell Biology, Schillingallee 69, 18057 Rostock (Germany); Finke, B.; Hempel, F. [Leibniz Institute for Plasma Science and Technology, Felix-Hausdorff Str. 2, 17489 Greifswald (Germany); Nebe, B. [University of Rostock, Biomedical Research Center, Department of Cell Biology, Schillingallee 69, 18057 Rostock (Germany); Meichsner, J. [University of Greifswald, Institute of Physics, Felix-Hausdorff Str. 6, 17489 Greifswald (Germany)

    2013-10-15

    Thin plasma polymer films from ethylenediamine were deposited on planar substrates placed on the powered electrode of a low pressure capacitively coupled 13.56 MHz discharge. The chemical composition of the plasma polymer films was analyzed by Fourier Transform Infrared Reflection Absorption Spectroscopy (FT-IRRAS) as well as by X-ray photoelectron spectroscopy (XPS) after derivatization of the primary amino groups. The PPEDA films undergo an alteration during the storage in ambient air, particularly, due to reactions with oxygen. The molecular changes in PPEDA films were studied over a long-time period of 360 days. Simultaneously, the adhesion of human osteoblast-like cells MG-63 (ATCC) was investigated on PPEDA coated corundum blasted titanium alloy (Ti-6Al-4V), which is applied as implant material in orthopedic surgery. The cell adhesion was determined by flow cytometry and the cell shape was analyzed by scanning electron microscopy. Compared to uncoated reference samples a significantly enhanced cell adhesion and proliferation were measured for PPEDA coated samples, which have been maintained after long-time storage in ambient air and additional sterilization by γ−irradiation. - Highlights: • Development of cell-adhesive nitrogen-rich coatings for biomedical applications. • Plasma polymer films from low pressure 13.56 MHz discharge in argon-ethylenediamine. • Enhanced osteoblast adhesion/proliferation on coated implant material (Ti-6Al-4V). • Despite film aging over 360 days the enhanced cell adhesion of the coating remains. • No influence of additional y-sterilization on the enhanced cell adhesion.

  3. Enhanced cell adhesion on bioinert ceramics mediated by the osteogenic cell membrane enzyme alkaline phosphatase.

    Science.gov (United States)

    Aminian, Alieh; Shirzadi, Bahareh; Azizi, Zahra; Maedler, Kathrin; Volkmann, Eike; Hildebrand, Nils; Maas, Michael; Treccani, Laura; Rezwan, Kurosch

    2016-12-01

    Functional bone and dental implant materials are required to guide cell response, offering cues that provide specific instructions to cells at the implant/tissue interface while maintaining full biocompatibility as well as the desired structural requirements and functions. In this work we investigate the influence of covalently immobilized alkaline phosphatase (ALP), an enzyme involved in bone mineralization, on the first contact and initial cell adhesion. To this end, ALP is covalently immobilized by carbodiimide-mediated chemoligation on two highly bioinert ceramics, alpha-alumina (Al2O3) and yttria-stabilized zirconia (Y-TZP) that are well-established for load-bearing applications. The physicochemical surface properties are evaluated by profilometry, zeta potential and water contact angle measurements. The initial cell adhesion of human osteoblasts (HOBs), human osteoblast-like cells (MG-63) and mesenchymal stromal cells (hMSCs) was investigated. Cell adhesion was assessed at serum free condition via quantification of percentage of adherent cells, adhesion area and staining of the focal adhesion protein vinculin. Our findings show that after ALP immobilization, the Al2O3 and Y-TZP surfaces gained a negative charge and their hydrophilicity was increased. In the presence of surface-immobilized ALP, a higher cell adhesion, more pronounced cell spreading and a higher number of focal contact points were found. Thereby, this work gives evidence that surface functionalization with ALP can be utilized to modify inert materials for biological conversion and faster bone regeneration on inert and potentially load-bearing implant materials. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Cadherin-mediated cell adhesion is critical for the closing of the mouse optic fissure.

    Directory of Open Access Journals (Sweden)

    Shuyi Chen

    Full Text Available Coloboma is a congenital disease that contributes significantly to childhood blindness. It results from the failure in closing the optic fissure, a transient opening on the ventral side of the developing eye. Although human and mouse genetic studies have identified a number of genes associated with coloboma, the detailed cellular mechanisms underlying the optic fissure closure and coloboma formation remain largely undefined. N-cadherin-mediated cell adhesion has been shown to be important for the optic fissure closure in zebrafish, but it remains to be determined experimentally how cell-cell adhesions are involved in the mammalian optic fissure closing process. α-Catenin is required for cell adhesion mediated by all of the classic cadherin molecules, including N-cadherin. In this study, we used the Cre-mediated conditional knockout technique to specifically delete α-catenin from the developing mouse eye to show that it is required for the successful closing of the optic fissure. In α-catenin conditional mutant optic cups, the major cell fates, including the optic fissure margin, neural retina and retinal pigmented epithelium, are specified normally, and the retinal progenitor cells proliferate normally. However, adherens junctions components, including N-cadherin, β-catenin and filamentous actin, fail to accumulate on the apical side of α-catenin mutant retinal progenitor cells, where adherens junctions are normally abundant, and the organization of the neural retina and the optic fissure margin is disrupted. Finally, the α-catenin mutant retina gradually degenerates in the adult mouse eye. Therefore, our results show that α-catenin-mediated cell adhesion and cell organization are important for the fissure closure in mice, and further suggest that genes that regulate cell adhesion may underlie certain coloboma cases in humans.

  5. Comprehensive peptidomic and glycomic evaluation reveals that sweet whey permeate from colostrum is a source of milk protein-derived peptides and oligosaccharides

    Science.gov (United States)

    Dallas, David C.; Weinborn, Valerie; de Moura Bell, Juliana M.L.N.; Wang, Meng; Parker, Evan A.; Guerrero, Andres; Hettinga, Kasper A.; Lebrilla, Carlito B.; German, J. Bruce; Barile, Daniela

    2014-01-01

    Whey permeate is a co-product obtained when cheese whey is passed through an ultrafiltration membrane to concentrate whey proteins. Whey proteins are retained by the membrane, whereas the low-molecular weight compounds such as lactose, salts, oligosaccharides and peptides pass through the membrane yielding whey permeate. Research shows that bovine milk from healthy cows contains hundreds of naturally occurring peptides – many of which are homologous with known antimicrobial and immunomodulatory peptides – and nearly 50 oligosaccharide compositions (not including structural isomers). As these endogenous peptides and oligosaccharides have low-molecular weight and whey permeate is currently an under-utilized product stream of the dairy industry, we hypothesized that whey permeate may serve as an inexpensive source of naturally occurring functional peptides and oligosaccharides. Laboratory fractionation of endogenous peptides and oligosaccharides from bovine colostrum sweet whey was expanded to pilot-scale. The membrane fractionation methodology used was similar to the methods commonly used industrially to produce whey protein concentrate and whey permeate. Pilot-scale fractionation was compared to laboratory-scale fractionation with regard to the identified peptides and oligosaccharide compositions. Results were interpreted on the basis of whether industrial whey permeate could eventually serve as a source of functional peptides and oligosaccharides. The majority (96%) of peptide sequences and the majority (96%) of oligosaccharide compositions found in the laboratory-scale process were mirrored in the pilot-scale process. Moreover, the pilot-scale process recovered an additional 33 peptides and 1 oligosaccharide not identified from the laboratory-scale extraction. Both laboratory- and pilot-scale processes yielded peptides deriving primarily from the protein β-casein. The similarity of the laboratory-and pilot-scale's resulting peptide and oligosaccharide

  6. Comprehensive peptidomic and glycomic evaluation reveals that sweet whey permeate from colostrum is a source of milk protein-derived peptides and oligosaccharides.

    Science.gov (United States)

    Dallas, David C; Weinborn, Valerie; de Moura Bell, Juliana M L N; Wang, Meng; Parker, Evan A; Guerrero, Andres; Hettinga, Kasper A; Lebrilla, Carlito B; German, J Bruce; Barile, Daniela

    2014-09-01

    Whey permeate is a co-product obtained when cheese whey is passed through an ultrafiltration membrane to concentrate whey proteins. Whey proteins are retained by the membrane, whereas the low-molecular weight compounds such as lactose, salts, oligosaccharides and peptides pass through the membrane yielding whey permeate. Research shows that bovine milk from healthy cows contains hundreds of naturally occurring peptides - many of which are homologous with known antimicrobial and immunomodulatory peptides - and nearly 50 oligosaccharide compositions (not including structural isomers). As these endogenous peptides and oligosaccharides have low-molecular weight and whey permeate is currently an under-utilized product stream of the dairy industry, we hypothesized that whey permeate may serve as an inexpensive source of naturally occurring functional peptides and oligosaccharides. Laboratory fractionation of endogenous peptides and oligosaccharides from bovine colostrum sweet whey was expanded to pilot-scale. The membrane fractionation methodology used was similar to the methods commonly used industrially to produce whey protein concentrate and whey permeate. Pilot-scale fractionation was compared to laboratory-scale fractionation with regard to the identified peptides and oligosaccharide compositions. Results were interpreted on the basis of whether industrial whey permeate could eventually serve as a source of functional peptides and oligosaccharides. The majority (96%) of peptide sequences and the majority (96%) of oligosaccharide compositions found in the laboratory-scale process were mirrored in the pilot-scale process. Moreover, the pilot-scale process recovered an additional 33 peptides and 1 oligosaccharide not identified from the laboratory-scale extraction. Both laboratory- and pilot-scale processes yielded peptides deriving primarily from the protein β-casein. The similarity of the laboratory-and pilot-scale's resulting peptide and oligosaccharide profiles

  7. Mechanism of mast cell adhesion to human tenocytes in vitro.

    Science.gov (United States)

    Behzad, Hayedeh; Tsai, Shu-Huei; Nassab, Paulina; Mousavizadeh, Rouhollah; McCormack, Robert G; Scott, Alex

    2015-01-01

    Mast cells and fibroblasts are two key players involved in many fibrotic and degenerative disorders. In the present study we examined the nature of binding interactions between human mast cells and tendon fibroblasts (tenocytes). In the mast cell-fibroblast co-culture model, mast cells were shown to spontaneously bind to tenocytes, in a process that was partially mediated by α5β1 integrin receptors. The same receptors on mast cells significantly mediated binding of these cells to tissue culture plates in the presence of tenocyte-conditioned media; the tenocyte-derived fibronectin in the media was shown to also play a major role in these binding activities. Upon binding to tenocytes or tissue culture plates, mast cells acquired an elongated phenotype, which was dependent on α5β1 integrin and tenocyte fibronectin. Additionally, tenocyte-derived fibronectin significantly enhanced mRNA expression of the adhesion molecule, THY1, by mast cells. Our data suggests that α5β1 integrin mediates binding of mast cells to human tenocyte and to tenocyte-derived ECM proteins, in particular fibronectin.

  8. Targeting cell adhesion molecules with nanoparticles using in vivo and flow-based in vitro models of atherosclerosis.

    Science.gov (United States)

    Khodabandehlou, Khosrow; Masehi-Lano, Jacqueline J; Poon, Christopher; Wang, Jonathan; Chung, Eun Ji

    2017-04-01

    Atherosclerosis is a leading cause of death worldwide; in addition to lipid dysfunction, chronic arterial wall inflammation is a key component of atherosclerosis. Techniques that target cell adhesion molecules, which are overexpressed during inflammation, are effective methods to detect and treat atherosclerosis. Specifically, research groups have identified vascular cell adhesion molecule-1, intercellular adhesion molecule-1, platelet endothelial cell adhesion molecule, and selectins (E-selectin and P-selectin) as correlated to atherogenesis. In this review, we discuss recent strategies both in vivo and in vitro that target cell adhesion molecules. First, we discuss peptide-based and antibody (Ab)-based nanoparticles utilized in vivo for diagnostic, therapeutic, and theranostic applications. Second, we discuss flow-based in vitro models that serve to reduce the traditional disadvantages of in vivo studies such as variability, time to develop the disease, and ethical burden, but preserve physiological relevance. The knowledge gained from these targeting studies can be translated into clinical solutions for improved detection, prevention, and treatment of atherosclerosis. Impact statement As atherosclerosis remains the leading cause of death, there is an urgent need to develop better tools for treatment of the disease. The ability to improve current treatments relies on enhancing the accuracy of in vitro and in vivo atherosclerotic models. While in vivo models provide all the relevant testing parameters, variability between animals and among models used is a barrier to reproducible results and comparability of NP efficacy. In vitro cultures isolate cells into microenvironments that fail to take into account flow separation and shear stress, which are characteristics of atherosclerotic lesions. Flow-based in vitro models provide more physiologically relevant platforms, bridging the gap between in vivo and 2D in vitro models. This is the first review that

  9. Muraymycin nucleoside-peptide antibiotics: uridine-derived natural products as lead structures for the development of novel antibacterial agents

    Science.gov (United States)

    Wirth, Marius; Niro, Giuliana; Leyerer, Kristin

    2016-01-01

    Summary Muraymycins are a promising class of antimicrobial natural products. These uridine-derived nucleoside-peptide antibiotics inhibit the bacterial membrane protein translocase I (MraY), a key enzyme in the intracellular part of peptidoglycan biosynthesis. This review describes the structures of naturally occurring muraymycins, their mode of action, synthetic access to muraymycins and their analogues, some structure–activity relationship (SAR) studies and first insights into muraymycin biosynthesis. It therefore provides an overview on the current state of research, as well as an outlook on possible future developments in this field. PMID:27340469

  10. Muraymycin nucleoside-peptide antibiotics: uridine-derived natural products as lead structures for the development of novel antibacterial agents

    Directory of Open Access Journals (Sweden)

    Daniel Wiegmann

    2016-04-01

    Full Text Available Muraymycins are a promising class of antimicrobial natural products. These uridine-derived nucleoside-peptide antibiotics inhibit the bacterial membrane protein translocase I (MraY, a key enzyme in the intracellular part of peptidoglycan biosynthesis. This review describes the structures of naturally occurring muraymycins, their mode of action, synthetic access to muraymycins and their analogues, some structure–activity relationship (SAR studies and first insights into muraymycin biosynthesis. It therefore provides an overview on the current state of research, as well as an outlook on possible future developments in this field.

  11. Soluble Vascular Cell Adhesion Molecule-1 (VCAM-1) as a Biomarker in the Mouse Model of Experimental Autoimmune Myocarditis (EAM)

    Science.gov (United States)

    Grabmaier, U.; Kania, G.; Kreiner, J.; Grabmeier, J.; Uhl, A.; Huber, B. C.; Lackermair, K.; Herbach, N.; Todica, A.; Eriksson, U.; Weckbach, L. T.; Brunner, S.

    2016-01-01

    Vascular cell adhesion molecule-1 (VCAM-1) is strongly upregulated in hearts of mice with coxsackie virus-induced as well as in patients with viral infection-triggered dilated cardiomyopathy. Nevertheless, the role of its soluble form as a biomarker in inflammatory heart diseases remains unclear. Therefore, we investigated whether plasma levels of soluble VCAM-1 (sVCAM-1) directly correlated with disease activity and progression of cardiac dysfunction in the mouse model of experimental autoimmune myocarditis (EAM). EAM was induced by immunization of BALB/c mice with heart-specific myosin-alpha heavy chain peptide together with complete Freund`s adjuvant. ELISA revealed strong expression of cardiac VCAM-1 (cVCAM-1) throughout the course of EAM in immunized mice compared to control animals. Furthermore, sVCAM-1 was elevated in the plasma of immunized compared to control mice at acute and chronic stages of the disease. sVCAM-1 did not correlate with the degree of acute cardiac inflammation analyzed by histology or cardiac cytokine expression investigated by ELISA. Nevertheless, heart to body weight ratio correlated significantly with sVCAM-1 at chronic stages of EAM. Cardiac systolic dysfunction studied with positron emission tomography indicated a weak relationship with sVCAM-1 at the chronic stage of the disease. Our data provide evidence that plasma levels of sVCAM-1 are elevated throughout all stages of the disease but showed no strong correlation with the severity of EAM. PMID:27501319

  12. Combinational Effect of Cell Adhesion Biomolecules and Their Immobilized Polymer Property to Enhance Cell-Selective Adhesion

    Directory of Open Access Journals (Sweden)

    Rio Kurimoto

    2016-01-01

    Full Text Available Although surface immobilization of medical devices with bioactive molecules is one of the most widely used strategies to improve biocompatibility, the physicochemical properties of the biomaterials significantly impact the activity of the immobilized molecules. Herein we investigate the combinational effects of cell-selective biomolecules and the hydrophobicity/hydrophilicity of the polymeric substrate on selective adhesion of endothelial cells (ECs, fibroblasts (FBs, and smooth muscle cells (SMCs. To control the polymeric substrate, biomolecules are immobilized on thermoresponsive poly(N-isopropylacrylamide-co-2-carboxyisopropylacrylamide (poly(NIPAAm-co-CIPAAm-grafted glass surfaces. By switching the molecular conformation of the biomolecule-immobilized polymers, the cell-selective adhesion performances are evaluated. In case of RGDS (Arg-Gly-Asp-Ser peptide-immobilized surfaces, all cell types adhere well regardless of the surface hydrophobicity. On the other hand, a tri-Arg-immobilized surface exhibits FB-selectivity when the surface is hydrophilic. Additionally, a tri-Ile-immobilized surface exhibits EC-selective cell adhesion when the surface is hydrophobic. We believe that the proposed concept, which is used to investigate the biomolecule-immobilized surface combination, is important to produce new