Yu Bin Lee

Hanyang University, Sŏul, Seoul, South Korea

Are you Yu Bin Lee?

Claim your profile

Publications (11)67.33 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Current advances in biomaterial fabrication techniques have broadened their application in different realms of biomedical engineering, spanning from drug delivery to tissue engineering. The success of biomaterials depends highly on the ability to modulate cell and tissue responses, including cell adhesion, as well as induction of repair and immune processes. Thus, most recent approaches in the field have concentrated on functionalizing biomaterials with different biomolecules intended to evoke cell- and tissue-specific reactions. Marine mussels produce mussel adhesive proteins (MAPs), which help them strongly attach to different surfaces, even under wet conditions in the ocean. Inspired by mussel adhesiveness, scientists discovered that dopamine undergoes self-polymerization at alkaline conditions. This reaction provides a universal coating for metals, polymers, and ceramics, regardless of their chemical and physical properties. Furthermore, this polymerized layer is enriched with catechol groups that enable immobilization of primary amine or thiol-based biomolecules via a simple dipping process. Herein, this review explores the versatile surface modification techniques that have recently been exploited in tissue engineering and summarizes polydopamine polymerization mechanisms, coating process parameters and effects on substrate properties. A brief discussion of polydopamine-based reactions in the context of engineering various tissue types, including bone, blood vessels, cartilage, nerves and muscle, is additionally provided.
    Biomacromolecules 08/2015; DOI:10.1021/acs.biomac.5b00852 · 5.75 Impact Factor
  • Yunhoe Heo · Young Min Shin · Yu Bin Lee · Youn Mook Lim · Heungsoo Shin
    [Show abstract] [Hide abstract]
    ABSTRACT: Regeneration of healthy endothelium onto vascular graft materials is imperative for prevention of intimal hyperplasia and thrombogenesis. In this study, we investigated the effect of collagen type IV (COL-IV) immobilized onto electrospun nanofibers on modulation of endothelial cell (EC) function, as a potential signal to rapid endothelialization of vascular grafts. COL-IV is assembled in basement membrane underneath intimal layer and regulates morphogenesis of blood vessels. For immobilization of COL-IV, poly(l-lactic acid) (PLLA) nanofibers (PL) were prepared as a model vascular graft substrate, onto which acrylic acid (AAc) was then grafted by using gamma-ray irradiation. AAc graft was dependent on irradiation doses and AAc concentrations, which allowed us to select the condition of 5% (v/v) AAc and 10kGy for further conjugation of COL-IV. COL-IV immobilization was proportionally controlled as a function of its concentration. Atomic force microscope (AFM) analysis qualitatively supported immobilization of COL-IV, demonstrating increase in root mean square roughness of the PL from 665.37±13.20nm to 1440.74±33.24. However, the Young's modulus of nanofibers was retained as approximately 1MPa, regardless of surface modification. The number of ECs attached on the nanofibers with immobilized COL-IV was significantly increased by 5 times (1052±138cells/mm(2)) from pristine PL (234±41cells/mm(2)). In addition, the effect of immobilized COL-IV was profound for enhancing proliferation and up-regulation of markers implicated in rapid endothelialization. Collectively, our results suggest that COL-IV immobilized onto electrospun PLLA nanofibers may serve as a promising instructive cue used in vascular graft materials. Copyright © 2015 Elsevier B.V. All rights reserved.
    Colloids and surfaces B: Biointerfaces 07/2015; 134:196-203. DOI:10.1016/j.colsurfb.2015.07.003 · 4.15 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Development of stem cell delivery system with ability of control over mutilineage differentiation and improved engraft efficiency is imperative in regenerative medicine. We herein report transfer stamping of human mesenchymal stem cells (hMSCs) patches using thermally expandable hydrogels with tunable cell-adhesive properties. The hydrogels were prepared from functionalized four arm copolymer of Tetronic(®), and the cell adhesion on the hydrogel was modulated by incorporation of fibronectin (FN) or cell-adhesive peptide (RGD). The resulting hydrogels showed spontaneous expansion in size within 10 min in response to the temperature reduction from 37 to 4°C. The adhesion and proliferation of hMSCs on FN-hydrogels were positively tunable in proportion to the amount of FN within hydrogels with complete monolayer of hMSCs (hMSC patch) being successfully achieved. The hMSC patch on the hydrogel was faced to the target substrate, which was then easily detached and re-attached to the target when the temperature was reduced from 37°C up to 4°C. We found that the transfer stamping of cell patch was facilitated at lower temperature of 4°C relative to 25°C, with the use of thinner hydrogels (0.5 mm in thickness relatively to 1.0 or 1.5 mm) and longer transfer time (>15 min). Notably, the hMSC patch was simply transferred from the hydrogel to the subcutaneous mouse skin tissue within 15 min with cold saline solution being dropped to the hydrogel. The hMSC patch following osteogenic or adipogenic commitment was also achieved with long-term culture of hMSCs on the hydrogel, which was successfully detached to the target surface. These results suggest that the hydrogels with thermally expandable and tunable cell-adhesive properties may serve as a universal substrate to harvest hMSC patch in a reliable and effective manner, which could potentially be utilized in many cell-sheet based therapeutic applications. Copyright © 2015 Elsevier Ltd. All rights reserved.
    Biomaterials 06/2015; 54. DOI:10.1016/j.biomaterials.2015.03.016 · 8.31 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Natural vessel has three types of concentric cell layers that perform their specific functions. Here, the fabrication of vascular structure is reported by transfer printing of three different cell layers using thermosensitive hydrogels. Tetronic–tyramine and RGD peptide are co-crosslinked to prepare cell adhesive and thermosensitive hydrogels. The hydrogel increases its diameter by 1.26 times when the temperature reduces from 37 °C to 4 °C. At optimized seeding density, three types of cells form monolayers on the hydrogel, which is then transferred to the target surface within 3 min. Three monolayers are simultaneously transferred on one substrate with controlled shape and arrangement. The same approach is applied onto nanofiber scaffolds that are cultured for more than 5 d. Every type of monolayer shows proliferation and migration on nanofiber scaffolds, and the formation of robust cell–cell contact is revealed by CD31 staining in endothelial cell layer. A vascular structure with multicellular components is fabricated by transfer of three monolayers on nanofibers that are manually rolled with the diameter and length of the tube being approximately 3 mm and 12 mm, respectively. Collectively, it is concluded that the tissue transfer printing is a useful tool for constructing a vascular structure and mimicking natural structure of different types of tissues.
    Advanced Healthcare Materials 09/2014; 3(9). DOI:10.1002/adhm.201300548 · 4.88 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In this study, thermosensitive hydrogels incorporated with multiple cell-interactive factors were developed as a substrate to form monolayer of human umbilical vein endothelial cells (HUVECs) that can be detached and transferrable to target sites as a cell-sheet in response to temperature change. The cell adhesive peptide (RGD) and growth factor (bFGF) covalently incorporated within the hydrogel significantly enhanced adhesion and proliferation of HUVECs, allowing for the formation of their confluent monolayer. Meanwhile, the precisely controllable change in the size of the hydrogels was observed by a repeated increase and decrease in temperature from 37 to 4 °C. By exploiting this unique behavior, the detachment and transfer of HUVEC sheet confluently cultured at 37 °C was rapidly induced within 10 min by expansion of the hydrogels when the temperature was decreased to 4 °C. The transferred cell sheet was highly viable and maintained robust cell-cell junction. Finally, the process of cell sheet transfer was directly applied onto an ischemic injury in the hind limb of mice. The transplanted HUVECs as a sheet retarded tissue necrosis over 14 days in comparison with that of direct injection of the same number of cells. Our results suggest that the developed multifunctional Tetronic-tyramine hydrogels could serve as an ideal substrate to modulate the formation of an endothelial cell layer that could potentially be utilized to treat peripheral arterial disease.
    Biomacromolecules 11/2013; 14(12). DOI:10.1021/bm4011744 · 5.75 Impact Factor
  • Source
    Biomaterials 11/2012; 33(32):8186–8187. DOI:10.1016/j.biomaterials.2012.08.001 · 8.31 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In this study, we introduced a simple method for polydopamine-mediated immobilization of dual bioactive factors for the preparation of functionalized vascular graft materials. Polydopamine was deposited on elastic and biodegradable poly(lactic acid-co-ɛ-caprolactone) (PLCL) films, and a cell adhesive RGD-containing peptide and basic fibroblast growth factor were subsequently immobilized by simple dipping. We used an enzyme-linked immunosorbent assay and fluorescamine assay to confirm that we had stably immobilized bioactive molecules on the polydopamine-coated PLCL film in a reaction time-dependent manner. When human umbilical vein endothelial cells (HUVEC) were cultured on the prepared substrates, the number of adherent cells and proliferation of HUVEC for up to 14 days were greatest on the film immobilized with dual factors. On the other hand, the film immobilized with RGD peptide exhibited the highest migration speed compared to the other groups. The expression of cluster of differentiation 31 and von Willebrand factor, which indicates maturation of endothelial cells, was highly stimulated in the dual factor-immobilized group, and passively adsorbed factors showed a negligible effect. The immobilization of bioactive molecules inspired by polydopamine was successful, and adhesion, migration, proliferation and differentiation of HUVEC were synergistically accelerated by the presence of multiple signaling factors. Collectively, our results have demonstrated that a simple coating with polydopamine enables the immobilization of multiple bioactive molecules for preparation of polymeric functionalized vascular graft materials.
    Biomaterials 08/2012; 33(33):8343-52. DOI:10.1016/j.biomaterials.2012.08.011 · 8.31 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Surface modification of tissue engineering scaffolds and substrates is required for improving the efficacy of stem cell therapy by generating physicochemical stimulation promoting proliferation and differentiation of stem cells. However, typical surface modification methods including chemical conjugation or physical absorption have several limitations such as multistep, complicated procedures, surface denaturation, batch-to-batch inconsistencies, and low surface conjugation efficiency. In this study, we report a mussel-inspired, biomimetic approach to surface modification for efficient and reliable manipulation of human neural stem cell (NSC) differentiation and proliferation. Our study demonstrates that polydopamine coating facilitates highly efficient, simple immobilization of neurotrophic growth factors and adhesion peptides onto polymer substrates. The growth factor or peptide-immobilized substrates greatly enhance differentiation and proliferation of human NSCs (human fetal brain-derived NSCs and human induced pluripotent stem cell-derived NSCs) at a level comparable or greater than currently available animal-derived coating materials (Matrigel) with safety issues. Therefore, polydopamine-mediated surface modification can provide a versatile platform technology for developing chemically defined, safe, functional substrates and scaffolds for therapeutic applications of human NSCs.
    Biomaterials 07/2012; 33(29):6952-64. DOI:10.1016/j.biomaterials.2012.06.067 · 8.31 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Most polymeric vascular prosthetic materials have low patency rate for replacement of small diameter vessels (<5 mm), mainly due to failure to generate healthy endothelium. In this study, we present polydopamine-mediated immobilization of growth factors on the surface of polymeric materials as a versatile tool to modify surface characteristics of vascular grafts potentially for accelerated endothelialization. Polydopamine was deposited on the surface of biocompatible poly(L-lactide-co-ε-caprolactone) (PLCL) elastomer, on which vascular endothelial growth factor (VEGF) was subsequently immobilized by simple dipping. Surface characteristics and composition were investigated by using scanning electron microscopy, atomic force microscopy, and X-ray photoelectron spectroscopy. Immobilization of VEGF on the polydopamine-deposited PLCL films was effective (19.8 ± 0.4 and 197.4 ± 19.7 ng/cm(2) for DPv20 and DPv200 films, respectively), and biotin-mediated labeling of immobilized VEGF revealed that the fluorescence intensity increased as a function of the concentration of VEGF solution. The effect of VEGF on adhesion of HUVECs was marginal, which may have been masked by polydopamine layer that also enhanced cell adhesion. However, VEGF-immobilized substrate significantly enhanced proliferation of HUVECs for over 7 days of in vitro culture and also improved their migration. In addition, immobilized VEGF supported robust cell to cell interactions with strong expression of CD 31 marker. The same process was effective for immobilization of basic fibroblast growth factor, demonstrating the robustness of polydopamine layer for secondary ligation of growth factors as a simple and novel surface modification strategy for vascular graft materials.
    Biomacromolecules 05/2012; 13(7):2020-8. DOI:10.1021/bm300194b · 5.75 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Blends of PAni and PLCL are electrospun to prepare uniform fibers for the development of electrically conductive, engineered nerve grafts. PC12 cell viability is significantly higher on RPACL fibers than on PLCL-only fibers, and the electrical conductivity of the fibers affects the differentiation of PC12 cells; the number of cells positively-stained and their expression level are significantly higher on RPACL fibers. PC12 cell bodies display an oriented morphology with outgrowing neurites. On RPACL fibers, the expression level of paxillin, cdc-42, and rac is positively affected and proteins including RhoA and ERK exist as more activated state. These results suggest that electroactive fibers may hold promise as a guidance scaffold for neuronal tissue engineering.
    Macromolecular Bioscience 03/2012; 12(3):402-11. DOI:10.1002/mabi.201100333 · 3.65 Impact Factor
  • Young Min Shin · Yu Bin Lee · Heungsoo Shin
    [Show abstract] [Hide abstract]
    ABSTRACT: Surface properties of biomaterials, such as hydrophobic/hydrophilic balance, chemical group distribution, and topography play important roles in regulation of many cellular behaviors. In this study, we present a bio-inspired coating of synthetic biodegradable poly(L-lactide-co-ɛ-caprolactone) (PLCL) films by using polydopamine for tunable cell behaviors such as adhesion and proliferation. Polydopamine coating decreased the water contact angles of the PLCL film from 75° to 40°, while the amount of coated polydopamine increased from 0.6 μg/cm(2) to 177.9 μg/cm(2). During the process, dopamine could be directly polymerized on the surface of the PLCL film to form a thin layer or nanosized particles of self-aggregates, which resulted in increase of overall roughness in a time-dependent manner. Characterization of surface atomic composition revealed an increase in signals from nitrogen and the C-N bond, both suggesting homogeneous polydopamine coating with prolonged coating time. The mechanical properties were similar following reaction with polydopamine for a time shorter than 30 min, while alterations in elongation and Young's modulus were observed when the coating time exceeded 240 min. Cell adhesion and proliferation on the polydopamine-coated films were significantly greater than those on the non-coated films. Interestingly, these cell behaviors were significantly improved even under the minimal coating time (5 min). In summary, the bio-inspired coating is of use to generate modular surface of biomaterial based on synthetic poly(α-hydroxy ester)s for tunable cell behaviors with optimization of coating time within the range in which their mechanical properties are not compromised.
    Colloids and surfaces B: Biointerfaces 10/2011; 87(1):79-87. DOI:10.1016/j.colsurfb.2011.05.004 · 4.15 Impact Factor