A simple, versatile, protein-repulsive, substrate-independent biomimetic surface modification is presented that is based on the creation of a PEO brush on a polydopamine anchoring layer and its capacity for selective follow-up modifications with various ligands using a copper-catalyzed alkyne-azide cycloaddition reaction. The desired surface concentration of peptide biomimetic ligands can be controlled by adjusting the peptide concentration in the reaction mixture, then measuring the activity of (125)I-radiolabeled peptides that are immobilized on the substrates. The performance of the prepared substrates is tested in cell cultures with MEF cells and a human ECC line.

• MeSH
• biomimetika * MeSH
• cyklizace MeSH
• kultivované buňky MeSH
• lidé MeSH
• povrchové vlastnosti MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Protein-repulsive surfaces modified with ligands for cell adhesion receptors have been widely developed for controlling the cell adhesion and growth in tissue engineering. However, the question of matrix production and deposition by cells on these surfaces has rarely been addressed. In this study, protein-repulsive polydopamine-poly(ethylene oxide) (PDA-PEO) surfaces were functionalized with an RGD-containing peptide (RGD), with a collagen-derived peptide binding fibronectin (Col), or by a combination of these peptides (RGD + Col, ratio 1:1) in concentrations of 90 fmol/cm(2) and 700 fmol/cm(2) for each peptide type. When seeded with vascular endothelial CPAE cells, the PDA-PEO surfaces proved to be completely non-adhesive for cells. On surfaces with lower peptide concentrations and from days 1 to 3 after seeding, cell adhesion and growth was restored practically only on the RGD-modified surface. However, from days 3 to 7, cell adhesion and growth was improved on surfaces modified with Col and with RGD + Col. At higher peptide concentrations, the cell adhesion and growth was markedly improved on all peptide-modified surfaces in both culture intervals. However, the collagen-derived peptide did not increase the expression of fibronectin in the cells. The deposition of fibronectin on the material surface was generally very low and similar on all peptide-modified surfaces. Nevertheless, the RGD + Col surfaces exhibited the highest cell adhesion stability under a dynamic load, which correlated with the highest expression of talin and vinculin in the cells on these surfaces. A combination of RGD + Col therefore seems to be the most promising for surface modification of biomaterials, e.g. vascular prostheses.

• MeSH
• adsorpce MeSH
• biomimetika * MeSH
• buněčná adheze * MeSH
• exprese genu MeSH
• fibronektiny chemie   genetika   MeSH
• indoly chemie   MeSH
• kultivované buňky MeSH
• lidé MeSH
• molekulární sekvence - údaje MeSH
• oligopeptidy chemie   MeSH
• polyethylenglykoly chemie   MeSH
• polymery chemie   MeSH
• povrchové vlastnosti MeSH
• sekvence aminokyselin MeSH
• talin genetika   MeSH
• vinkulin genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

A novel and facile in vitro cell sensing system has been developed with one-step electropolymerization of the conducting polypyrrole(PPy) polymer using RGD peptide as the sole dopant on an indium tin oxide (ITO) surface. The resulted RGD peptide-doped polypyrrole (PPy/RGD) composite film had a robust surface, in which PPy provided a biocompatible matrix for cell growth and a conducting interface for electrical detection, while the RGD peptide entrapped in the PPy matrix conferred the desired biomimetic properties. Using the human lung cancer cell A549 as a model, this system can be used to monitor cell behaviors of proliferation and cytotoxicity.

• Klíčová slova
• RGD peptidy, elektropolymerizace, polypyrrole,
• MeSH
• antitumorózní látky toxicita   MeSH
• biomimetické materiály MeSH
• biosenzitivní techniky * MeSH
• oligopeptidy MeSH
• polymery MeSH
• proliferace buněk MeSH
• pyrroly * MeSH
• skenovací elektrochemická mikroskopie MeSH
• Publikační typ
• práce podpořená grantem MeSH

Antifouling polymer layers containing extracellular matrix-derived peptide motifs offer promising new options for biomimetic surface engineering. In this contribution, we report the design of antifouling vascular grafts bearing biofunctional peptide motifs for tissue regeneration applications based on hierarchical polymer brushes. Hierarchical diblock poly(methyl ether oligo(ethylene glycol) methacrylate-block-glycidyl methacrylate) brushes bearing azide groups (poly(MeOEGMA-block-GMA-N3)) were grown by surface-initiated atom transfer radical polymerization (SI-ATRP) and functionalized with biomimetic RGD peptide sequences. Varying the conditions of copper-catalyzed alkyne-azide "click" reaction allowed for the immobilization of RGD peptides in a wide surface concentration range. The synthesized hierarchical polymer brushes bearing peptide motifs were characterized in detail using various surface sensitive physicochemical methods. The hierarchical brushes presenting the RGD sequences provided excellent cell adhesion properties and at the same time remained resistant to fouling from blood plasma. The synthesis of anti-fouling hierarchical brushes bearing 1.2 × 103 nmol/cm2 RGD biomimetic sequences has been adapted for the surface modification of commercially available grafts of woven polyethylene terephthalate (PET) fibers. The fiber mesh was endowed with polymerization initiator groups via aminolysis and acylation reactions optimized for the material. The obtained bioactive antifouling vascular grafts promoted the specific adhesion and growth of endothelial cells, thus providing a potential avenue for endothelialization of artificial conduits.

• MeSH
• adsorpce MeSH
• aminokyselinové motivy MeSH
• azidy chemie   MeSH
• biokompatibilní potahované materiály * MeSH
• biomimetické materiály * MeSH
• buněčná adheze MeSH
• buněčné dělení MeSH
• cévní endotel fyziologie   MeSH
• cévní protézy * MeSH
• endoteliální buňky pupečníkové žíly (lidské) MeSH
• imobilizované proteiny MeSH
• křemík MeSH
• krevní plazma MeSH
• krevní proteiny MeSH
• lidé MeSH
• oligopeptidy chemie   MeSH
• polyethylentereftaláty chemie   MeSH
• polymerizace * MeSH
• povrchové vlastnosti MeSH
• řízená tkáňová regenerace přístrojové vybavení   MeSH
• sklo MeSH
• syntetická chemie okamžité shody MeSH
• testování materiálů MeSH
• trombóza prevence a kontrola   MeSH
• zlato MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH

The design of favorable mechanical properties and suitable surface modifications of hydrogels in order to stimulate specific cell response is a great challenge. N-(2-Hydroxypropyl) methacryl-amide (HPMA) was utilized to form macroporous cryogel scaffolds for stem cell applications. Furthermore, one group of scaffolds was enhanced by copolymerization of HPMA with methacryloyl-GGGRGDS-OH peptide in an effort to integrate biomimetic adhesion sites. The cryogels were characterized by stiffness and equilibrium swelling measurements as well as by scanning electron microscopy. Cell culture experiments were performed with human adipose-derived stem cells and substrates were found completely non-toxic. Moreover, RGDS-enriched cryogels supported cell attachment, spreading and proliferation, so they can be considered suitable for designed aims.

• MeSH
• akrylamidy * MeSH
• biokompatibilní materiály MeSH
• biomimetika * MeSH
• buněčná adheze MeSH
• kmenové buňky * MeSH
• kryogely MeSH
• kultivované buňky MeSH
• lidé MeSH
• poréznost MeSH
• proliferace buněk MeSH
• pružnost MeSH
• tkáňové podpůrné struktury MeSH
• tukové buňky MeSH
• voda chemie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

In this work we evaluate the applicability of different atomic force microscopy (AFM) modes, such as Phase Shift Imaging, Atomic Force Acoustic Microscopy (AFAM) and Force Spectroscopy, for mapping of the distribution pattern of low-molecular-weight biomimetic groups on polymer biomaterial surfaces. Patterns with either random or clustered spatial distribution of bioactive peptide group derived from fibronectin were prepared by surface deposition of functional block copolymer nano-colloids and grafted with RGDS peptide containing the sequence of amino acids arginine-glycine-aspartic acid-serine (conventionally labeled as RGDS) and carrying biotin as a tag. The biotin-tagged peptides were labeled with 40nm streptavidin-modified Au nanospheres. The peptide molecules were localized through the detection of bound Au nanospheres by AFM, and thus, the surface distribution of peptides was revealed. AFM techniques capable of monitoring local mechanical properties of the surface were proved to be the most efficient for identification of Au nano-markers. The efficiency was successfully demonstrated on two different patterns, i.e. random and clustered distribution of RGDS peptides on structured surface of the polymer biomaterial.

• MeSH
• fibronektiny chemie   MeSH
• mechanické jevy * MeSH
• mikroskopie atomárních sil metody   MeSH
• nanokuličky ultrastruktura   MeSH
• povrchové vlastnosti MeSH
• streptavidin chemie   MeSH
• zlato MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

In this study a strategy to immobilize phospholipids onto a polymer-based stationary phase is described. Methacrylate-based monoliths in capillary format (150×0.1mm) were modified by soybean phosphatidylcholine through 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide coupling to obtain stationary phases suitable to mimic cell surface membranes. The covalent coupling reaction involves the phosphate group in phospholipids; therefore, the described methodology is suitable for all types of phospholipids. Immobilization of soy bean phosphatidylcholine on the monolith was confirmed by attenuated total reflectance Fourier transform infrared spectroscopy and gas chromatography-mass spectrometry of the fatty alcohol profile, generated upon reductive cleavage of the fatty acyl side chains of the phospholipid on the monolith surface with lithium aluminium hydride. The prepared stationary phases were evaluated through studies on the retention of low-molar mass model analytes including neutral, acidic, and basic compounds. Liquid chromatographic studies confirmed predominant hydrophobic interactions between the analytes and the synthesized stationary phase; however, electrostatic interactions contributed to the retention as well. The synthesized columns showed high stability even with fully aqueous mobile phases such as Dulbecco's phosphate-buffered saline solution.

• MeSH
• biomimetika MeSH
• chemické techniky analytické přístrojové vybavení   metody   MeSH
• chromatografie kapalinová přístrojové vybavení   MeSH
• ethyldimethylaminopropylkarbodiimid chemie   MeSH
• fosfatidylcholiny chemie   MeSH
• fosfolipidy chemie   MeSH
• hydrofobní a hydrofilní interakce MeSH
• methakryláty chemie   MeSH
• polymery chemie   MeSH
• voda chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Polydopamine (PDA), also known as synthetic melanin, is widely used as a biomimetic anchoring layer for the modification of various solid substrates. PDA is utilized for a wide range of biomedical, sensing and tribological applications, even though the polymer's precise covalent structure has not been completely revealed yet. Even more, it is not evident to which extent the chemical nature of the substrate, on which the layer is formed, influences and predetermines the covalent structure of resulting PDA. In this contribution, we have studied the growth of PDA using various surface-sensitive techniques such as spectroscopic ellipsometry, atomic force microscopy and X-ray photoelectron spectroscopy. We supplemented grazing angle attenuated total reflection FTIR spectroscopy with multivariate statistical analysis to further gain analytical power. We have particularly focused on the effects of polymerization time and substrate on the PDA structure. We found notable differences in the chemical composition of PDA formed on gold and on surfaces terminated with oxides/reactive hydroxides such as silicon and N-dopped-TiO2 in the early stages of the layer formation. At the later stages of layer formation, a merely unified chemical structure was observed independently on the type of substrate.

• MeSH
• indoly * MeSH
• polymerizace MeSH
• polymery * MeSH
• povrchové vlastnosti MeSH
• Publikační typ
• časopisecké články MeSH

The C-type lectin DC-SIGN expressed on immature dendritic cells is a promising target for antiviral drug development. Previously, we have demonstrated that mono- and divalent C-glycosides based on d-manno and l-fuco configurations are promising DC-SIGN ligands. Here, we described the convergent synthesis of C-glycoside dendrimers decorated with 4, 6, 9, and 12 α-l-fucopyranosyl units and with 9 and 12 α-d-mannopyranosyl units. Their affinity against DC-SIGN was assessed by surface plasmon resonance (SPR) assays. For comparison, parent O-glycosidic dendrimers were synthesized and tested, as well. A clear increase of both affinity and multivalency effect was observed for C-glycomimetics of both types (mannose and fucose). However, when dodecavalent C-glycosidic dendrimers were compared, there was no difference in affinity regarding the sugar unit (l-fuco, IC50 17 μM; d-manno, IC50 12 μM). For the rest of glycodendrimers with l-fucose or d-mannose attached by the O- or C-glycosidic linkage, C-glycosidic dendrimers were significantly more active. These results show that in addition to the expected physiological stability, the biological activity of C-glycoside mimetics is higher in comparison to the corresponding O-glycosides and therefore these glycomimetic multivalent systems represent potentially promising candidates for targeting DC-SIGN.

• MeSH
• biomimetické materiály chemie   farmakologie   MeSH
• fukosa chemie   MeSH
• inhibiční koncentrace 50 MeSH
• lektiny typu C antagonisté a inhibitory   MeSH
• mannosa chemie   MeSH
• molekuly buněčné adheze antagonisté a inhibitory   MeSH
• receptory buněčného povrchu antagonisté a inhibitory   MeSH
• Publikační typ
• časopisecké články MeSH

Superporous poly(2-hydroxyethyl methacrylate) is successfully used as a scaffold material for tissue engineering; however, it lacks functional groups that support cell adhesion. The objective of this study was to investigate the cell-adhesive properties of biomimetic ligands, such as laminin-derived Ac-CGGASIKVAVS-OH (SIKVAV) peptide and fibronectin subunits (Fn), as well as small molecules exemplified by 2-mercaptoethanol (ME) and cysteine (Cys), immobilized on a copolymer of 2-hydroxyethyl methacrylate (HEMA) with 2-aminoethyl methacrylate (AEMA) by a maleimide-thiol coupling reaction. The maleimide group was introduced to the P(HEMA-AEMA) hydrogels by the reaction of their amino groups with N-γ-maleimidobutyryl-oxysuccinimide ester (GMBS). Mesenchymal stem cells (MSCs) were used to investigate the cell adhesive properties of the modified hydrogels. A significantly larger area of cell growth as well as a higher cell density were found on Fn- and SIKVAV-modified hydrogels when compared to the ME- and Cys-modified supports or neat P(HEMA-AEMA). Moreover, Fn-modification strongly stimulated cell proliferation. The ability of MSCs to differentiate into adipocytes and osteoblasts was maintained on both Fn- and SIKVAV-modifications, but it was reduced on ME-modified hydrogels and neat P(HEMA-AEMA). The results show that the immobilization of SIKVAV and Fn-subunits onto superporous P(HEMA-AEMA) hydrogels via a GMBS coupling reaction improves cell adhesive properties. The high proliferative activity observed on Fn-modified hydrogels suggests that the immobilized Fn-subunits maintain their bioactivity and thus represent a promising tool for application in tissue engineering.

• MeSH
• buněčná diferenciace MeSH
• cystein chemie   MeSH
• fibronektiny chemie   MeSH
• hydrogely * MeSH
• krysa rodu rattus MeSH
• merkaptoethanol chemie   MeSH
• mezenchymální kmenové buňky cytologie   MeSH
• mikroskopie elektronová rastrovací MeSH
• peptidy chemie   MeSH
• polyhydroxyethylmethakrylát chemie   MeSH
• povrchové vlastnosti MeSH
• tkáňové inženýrství * MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH