Publications by authors named "Hee-Young Park"

79 Publications

Synthesis of Sulfonated Poly(Arylene Ether Sulfone)s Containing Aliphatic Moieties for Effective Membrane Electrode Assembly Fabrication by Low-Temperature Decal Transfer Methods.

Polymers (Basel) 2021 May 24;13(11). Epub 2021 May 24.

Center for Hydrogen and Fuel Cell Research, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea.

The purpose of this study was to investigate the effect of the aliphatic moiety in the sulfonated poly(arylene ether sulfone) (SPAES) backbone. A new monomer (4,4'-dihydroxy-1,6-diphenoxyhexane) was synthesized and polymerized with other monomers to obtain partially alkylated SPAESs. According to differential scanning calorimetry analysis, the glass transition temperature (T) of these polymers ranged from 85 to 90 °C, which is 100 °C lower than that of the fully aromatic SPAES. Due to the low T values obtained for the partially alkylated SPAESs, it was possible to prepare a hydrocarbon electrolyte membrane-based membrane electrode assembly (MEA) with Nafion binder in the electrode through the use of a decal transfer method, which is the most commercially suitable system to obtain an MEA of proton exchange membrane fuel cells (PEMFCs). A single cell prepared using this partially alkylated SPAES as an electrolyte membrane exhibited a peak power density of 539 mW cm.
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http://dx.doi.org/10.3390/polym13111713DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8197277PMC
May 2021

Electrochemical Nitrogen Reduction Kinetics on a Copper Sulfide Catalyst for NH Synthesis at Low Temperature and Atmospheric Pressure.

ACS Appl Mater Interfaces 2021 Jun 7;13(21):24593-24603. Epub 2021 Apr 7.

Division of Energy & Environment Technology, KIST School, University of Science and Technology (UST), Seoul 02792, Republic of Korea.

We studied the electrochemical synthesis of NH on Fe-CuS/C catalysts in an alkaline aqueous solution under ambient conditions. The metal chalcogenide catalyst is active in the nitrogen reduction reaction (NRR) for approximately 45 min with an NH production yield of 16 μg h cm at -0.4 , while it decomposes to CuO. The rapid degradation of the catalyst hinders the precise investigation of the NH production activity in longer time measurements. Herein, the electrochemical NH production rate is enhanced with increased overpotentials when the degradation effect is mitigated in the measurement, which was difficult to observe in the NRR reports. In the Tafel analysis, the exchange current density, heterogeneous rate constant, and transfer coefficient of the Fe-CuS/C catalyst on the NRR were estimated. When the electrode degradation is mitigated, one of the best NH production activities among the reported metal sulfide electrochemical NRR catalysts is obtained, which is 42 μg h cm at -0.6 V.
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http://dx.doi.org/10.1021/acsami.1c00850DOI Listing
June 2021

Amphiphilic Ti porous transport layer for highly effective PEM unitized regenerative fuel cells.

Sci Adv 2021 Mar 24;7(13). Epub 2021 Mar 24.

Center for Hydrogen, Fuel Cell Research, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea.

Polymer electrolyte membrane unitized regenerative fuel cells (PEM-URFCs) require bifunctional porous transport layers (PTLs) to play contradictory roles in a single unitized system: hydrophobicity for water drainage in the fuel cell (FC) mode and hydrophilicity for water supplement in the electrolysis cell (EC) mode. Here, we report a high-performance amphiphilic Ti PTL suitable for both FC and EC modes, thanks to alternating hydrophobic and hydrophilic channels. To fabricate the amphiphilic PTL, we used a shadow mask patterning process using ultrathin polydimethylsiloxane (PDMS) brush as a hydrophobic surface modifier, which can change the Ti PTL's surface polarity without decreasing its electrical conductivity. Consequently, performance improved by 4.3 times in FC (@ 0.6 V) and 1.9 times in EC (@ 1.8 V) from amphiphilic PTL. To elucidate reason for performance enhancement, discrete gas emission through the hydrophobic channels in amphiphilic PTL was verified under scanning electrochemical microscopy.
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http://dx.doi.org/10.1126/sciadv.abf7866DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7990350PMC
March 2021

Polystyrene-Based Hydroxide-Ion-Conducting Ionomer: Binder Characteristics and Performance in Anion-Exchange Membrane Fuel Cells.

Polymers (Basel) 2021 Feb 25;13(5). Epub 2021 Feb 25.

Center for Hydrogen and Fuel Cell Research, Korea Institute of Science and Technology (KIST), Hwarang-ro 14-gil 5, Seongbuk-gu, Seoul 02792, Korea.

Polystyrene-based polymers with variable molecular weights are prepared by radical polymerization of styrene. Polystyrene is grafted with bromo-alkyl chains of different lengths through Friedel-Crafts acylation and quaternized to afford a series of hydroxide-ion-conducting ionomers for the catalyst binder for the membrane electrode assembly in anion-exchange membrane fuel cells (AEMFCs). Structural analyses reveal that the molecular weight of the polystyrene backbone ranges from 10,000 to 63,000 g mol, while the ion exchange capacity of quaternary-ammonium-group-bearing ionomers ranges from 1.44 to 1.74 mmol g. The performance of AEMFCs constructed using the prepared electrode ionomers is affected by several ionomer properties, and a maximal power density of 407 mW cm and a durability exceeding that of a reference cell with a commercially available ionomer are achieved under optimal conditions. Thus, the developed approach is concluded to be well suited for the fabrication of next-generation electrode ionomers for high-performance AEMFCs.
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http://dx.doi.org/10.3390/polym13050690DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7956690PMC
February 2021

High-yield electrochemical hydrogen peroxide production from an enhanced two-electron oxygen reduction pathway by mesoporous nitrogen-doped carbon and manganese hybrid electrocatalysts.

Nanoscale Horiz 2020 May 12;5(5):832-838. Epub 2020 Feb 12.

Center for Hydrogen and Fuel Cell Research, Korea Institute of Science and Technology (KIST), Hwarangno 14-gil 5, Seongbuk-gu, Seoul 02792, Republic of Korea.

Electrochemical hydrogen peroxide (HO) production by the direct two-electron (2e) oxygen reduction reaction (ORR) has received much attention as a promising alternative to the industrially developed anthraquinone fabrication process. Transition metal (M) and nitrogen doped carbon (M-N-C, M = Fe or Co) catalysts are known to be active for four electron ORR pathways via two + two electron transfer, where the former is for the ORR and the latter for the peroxide reduction reaction (PRR). Here, we report mesoporous N-doped carbon/manganese hybrid electrocatalysts composed of MnO and Mn-N coupled with N-doped carbons (Mn-O/[email protected]), which have led to the development of electrocatalysis towards the 2e ORR route. Based on the structural and electrochemical characterization, the number of transferred electrons during the ORR on the Mn-O/[email protected] was found to be close to the theoretical value of the 2e process, indicating their high activity toward HO. The favored ORR process arose due to the increased number of Mn-N sites within the mesoporous N-doped carbon materials. Furthermore, there was a strong indication that the PRR is significantly suppressed by adjacent MnO species, demonstrating its highly selective production of HO (>80%) from the oxygen electrochemical process. The results of a real fuel cell device test demonstrated that an Mn-O/[email protected] catalyst sustains a very stable current, and we attributed its outstanding activity to a combination of site-dependent facilitation of 2e transfer and a favorable porosity for mass transport.
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http://dx.doi.org/10.1039/c9nh00783kDOI Listing
May 2020

Human Tonsil-Derived Mesenchymal Stromal Cells Maintain Proliferating and ROS-Regulatory Properties via Stanniocalcin-1.

Cells 2020 03 6;9(3). Epub 2020 Mar 6.

Department of Life Science in Dentistry, School of Dentistry, Pusan National University, Yangsan 50612, Korea.

Mesenchymal stromal cells (MSCs) from various sources exhibit different potential for stemness and therapeutic abilities. Recently, we reported a unique MSCs from human palatine tonsil (TMSCs) and their superior proliferation capacity compared to MSCs from other sources. However, unique characteristics of each MSC are not yet precisely elucidated. We investigated the role of stanniocalcin-1 (STC1), an anti-oxidative hormone, in the functions of TMSCs. We found that STC1 was highly expressed in TMSC compared with MSCs from bone marrow or adipose tissue. The proliferation, senescence and differentiation of TMSCs were assessed after the inhibition of STC1 expression. STC1 inhibition resulted in a significant decrease in the proliferation of TMSCs and did not affect the differentiation potential. To reveal the anti-oxidative ability of STC1 in TMSCs themselves or against other cell types, the generation of mitochondrial reactive oxygen species (ROS) in TMSC or ROS-mediated production of interleukin (IL)-1β from macrophage-like cells were detected. Interestingly, the basal level of ROS generation in TMSCs was significantly elevated after STC1 inhibition. Moreover, down-regulation of STC1 impaired the inhibitory effect of TMSCs on IL-1β production in macrophages. Taken together, these findings indicate that STC1 is highly expressed in TMSCs and plays a critical role in proliferating and ROS-regulatory abilities.
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http://dx.doi.org/10.3390/cells9030636DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7140534PMC
March 2020

Tensin-3 Regulates Integrin-Mediated Proliferation and Differentiation of Tonsil-Derived Mesenchymal Stem Cells.

Cells 2019 Dec 30;9(1). Epub 2019 Dec 30.

Department of Otorhinolaryngology, Head and Neck Surgery, Pusan National University School of Medicine and Biomedical Research Institute, Pusan National University Hospital, Busan 49241, Korea.

Human palatine tonsils are potential tissue source of multipotent mesenchymal stem cells (MSCs). The proliferation rate of palatine tonsil-derived MSCs (TMSCs) is far higher than that of bone marrow-derived MSCs (BMSCs) or adipose tissue-derived MSCs (ADSCs). In our previous study, we had found through DNA microarray analysis that tensin-3 (TNS3), a type of focal adhesion protein, was more highly expressed in TMSCs than in both BMSCs and ADSCs. Here, the role of TNS3 in TMSCs and its relationship with integrin were investigated. TNS3 expression was significantly elevated in TMSCs than in other cell types. Cell growth curves revealed a significant decrease in the proliferation and migration of TMSCs treated with siRNA for TNS3 (siTNS3). siTNS3 treatment upregulated p16 and p21 levels and downregulated SOX2 expression and focal adhesion kinase, protein kinase B, and c-Jun N-terminal kinase phosphorylation. siTNS3 transfection significantly reduced adipogenic differentiation of TMSCs and slightly decreased osteogenic and chondrogenic differentiation. Furthermore, TNS3 inhibition reduced active integrin beta-1 (ITGβ1) expression, while total ITGβ1 expression was not affected. Inhibition of ITGβ1 expression in TMSCs by siRNA showed similar results observed in TNS3 inhibition. Thus, TNS3 may play an important role in TMSC proliferation and differentiation by regulating active ITGβ1 expression.
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http://dx.doi.org/10.3390/cells9010089DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7017379PMC
December 2019

Preoperative serum VEGF-C but not VEGF-A level is correlated with lateral neck metastasis in papillary thyroid carcinoma.

Head Neck 2019 08 7;41(8):2602-2609. Epub 2019 Mar 7.

Department of Otorhinolaryngology-Head and Neck Surgery, Biomedical Research Institute, Pusan National University Hospital, Pusan National University School of Medicine, Busan, Republic of Korea.

Background: This study aimed to investigate the relationships between serum vascular endothelial growth factor (VEGF)-A or VEGF-C levels and lymph node metastasis (LNM) status in patients with papillary thyroid carcinoma (PTC).

Methods: The study enrolled 150 patients with pathologically proven PTC who underwent surgery: PTC without LNM, PTC with central neck metastasis, and PTC with lateral neck metastasis.

Results: Preoperative serum VEGF-A levels were 300.12 ± 80.80 pg/mL overall and were not correlated with the presence of LNM. Preoperative serum VEGF-C levels were 132.41 ± 48.48 pg/mL overall and were significantly correlated with the presence of LNM. Serum VEGF-C levels were further increased in patients with lateral neck metastasis and positively correlated with the number of metastatic LNs (rho = 0.252, P = 0.002). Serum VEGF-C, but not VEGF-A, was identified as a significant predictor of lateral neck metastasis.

Conclusion: Serum VEGF-C might be a clinically relevant biomarker of lateral neck metastasis in patients with PTC.
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http://dx.doi.org/10.1002/hed.25729DOI Listing
August 2019

HeLa E-Box Binding Protein, HEB, Inhibits Promoter Activity of the Lysophosphatidic Acid Receptor Gene in Neocortical Neuroblast Cells.

Mol Cells 2019 Feb 2;42(2):123-134. Epub 2019 Jan 2.

Department of Pharmacology, College of Medicine, Institute of Natural Medicine, Hallym University, Chuncheon 24252, Korea.

Lysophosphatidic acid (LPA) is an endogenous lysophospholipid with signaling properties outside of the cell and it signals through specific G protein-coupled receptors, known as LPA. For one of its receptors, LPA (gene name , details on the cis-acting elements for transcriptional control have not been defined. Using 5'RACE analysis, we report the identification of an alternative transcription start site of mouse and characterize approximately 3,500 bp of non-coding flanking sequence 5' of mouse gene for promoter activity. Transient transfection of cells derived from mouse neocortical neuroblasts with constructs from the 5' regions of mouse gene revealed the region between -248 to +225 serving as the basal promoter for . This region also lacks a TATA box. For the region between -761 to -248, a negative regulatory element affected the basal expression of . This region has three E-box sequences and mutagenesis of these E-boxes, followed by transient expression, demonstrated that two of the E-boxes act as negative modulators of . One of these E-box sequences bound the HeLa E-box binding protein (HEB), and modulation of HEB levels in the transfected cells regulated the transcription of the reporter gene. Based on our data, we propose that HEB may be required for a proper regulation of expression in the embryonic neocortical neuroblast cells and to affect its function in both normal brain development and disease settings.
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http://dx.doi.org/10.14348/molcells.2018.0399DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6399008PMC
February 2019

Auricular Cartilage Regeneration with Adipose-Derived Stem Cells in Rabbits.

Mediators Inflamm 2018 18;2018:4267158. Epub 2018 Mar 18.

Department of Otorhinolaryngology and Biomedical Research Institute, Pusan National University School of Medicine, Pusan National University Hospital, Busan, Republic of Korea.

Tissue engineering cell-based therapy using induced pluripotent stem cells and adipose-derived stem cells (ASCs) may be promising tools for therapeutic applications in tissue engineering because of their abundance, relatively easy harvesting, and high proliferation potential. The purpose of this study was to investigate whether ASCs can promote the auricular cartilage regeneration in the rabbit. In order to assess their differentiation ability, ASCs were injected into the midportion of a surgically created auricular cartilage defect in the rabbit. Control group was injected with normal saline. After 1 month, the resected auricles were examined histopathologically and immunohistochemically. The expression of collagen type II and transforming growth factor-1 (TGF-1) were analyzed by quantitative polymerase chain reaction. Histopathology showed islands of new cartilage formation at the site of the surgically induced defect in the ASC group. Furthermore, Masson's trichrome staining and immunohistochemistry for S-100 showed numerous positive chondroblasts. The expression of collagen type II and TGF-1 were significantly higher in the ASCs than in the control group. In conclusion, ASCs have regenerative effects on the auricular cartilage defect of the rabbit. These effects would be expected to contribute significantly to the regeneration of damaged cartilage tissue .
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http://dx.doi.org/10.1155/2018/4267158DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5878874PMC
September 2018

The art and science of selecting graduate students in the biomedical sciences: Performance in doctoral study of the foundational sciences.

PLoS One 2018 3;13(4):e0193901. Epub 2018 Apr 3.

Department of Medicine, Biomedical Genetics Section, Boston University School of Medicine, Boston, Massachusetts, United States of America.

The goal of this study was to investigate associations between admissions criteria and performance in Ph.D. programs at Boston University School of Medicine. The initial phase of this project examined student performance in the classroom component of a newly established curriculum named "Foundations in Biomedical Sciences (FiBS)". Quantitative measures including undergraduate grade point average (GPA), graduate record examination (GRE; a standardized, computer-based test) scores for the verbal (assessment of test takers' ability to analyze, evaluate, and synthesize information and concepts provided in writing) and quantitative (assessment of test takers' problem-solving ability) components of the examination, previous research experience, and competitiveness of previous research institution were used in the study. These criteria were compared with competencies in the program defined as students who pass the curriculum as well as students categorized as High Performers. These data indicated that there is a significant positive correlation between FiBS performance and undergraduate GPA, GRE scores, and competitiveness of undergraduate institution. No significant correlations were found between FiBS performance and research background. By taking a data-driven approach to examine admissions and performance, we hope to refine our admissions criteria to facilitate an unbiased approach to recruitment of students in the life sciences and to share our strategy to support similar goals at other institutions.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0193901PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5882097PMC
July 2018

Evaluation of decellularized xenogenic porcine auricular cartilage as a novel biocompatible filler.

J Biomed Mater Res B Appl Biomater 2018 10 10;106(7):2708-2715. Epub 2018 Feb 10.

Department of Otorhinolaryngology-Head and Neck Surgery, Pusan National University School of Medicine and Biomedical Research Institute, Pusan National University Hospital, Pusan, Republic of Korea.

Fillers are products that fill the space in soft tissues of the human body and actively used in the various medical fields. Unfortunately, most of the cost-effective commercially available fillers are synthetic and have limitations in terms of their biocompatibility. Here, we evaluated the possible application of decellularized xenogenic cartilage as a long-lasting material for soft tissue augmentation and compared it with two commercially available fillers Artesense (polymethylmethacrylate microspheres) and Radiesse (calcium hydroxyapatite [CaHa]). To do so, porcine auricular cartilage was harvested, followed by freezing and grinding of the tissue into flakes. Then, we used 1% Triton X-100 to decellularize the flakes. We then, respectively, injected 0.1 cc of each material (decellularized xenogenic cartilage, Radiesse, and Artesense) into the subcutaneous layer at three different sites per subject in 12 Sprague-Dawley rats, and evaluated the inflammatory cell infiltration and foreign body reactions of each. Our data indicate that the infiltration of giant cells in the injection area was significantly lower in the decellularized xenogenic cartilage injection group than that in the Radiesse and Artesense injection groups. Further, we observed some neutrophil infiltration in the xenogenic cartilage and Artesense injection groups at 1 month, but these levels were much lower at 3 months (comparable to the Radiesse injection group). Thus, decellularized xenogenic cartilage may have a distinct advantage in terms of biocompatibility compared with other commercial injectable long-lasting fillers, making it one of the most feasible, natural, and cost effective materials in the market. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2708-2715, 2018.
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http://dx.doi.org/10.1002/jbm.b.34088DOI Listing
October 2018

Regenerative potential of tonsil mesenchymal stem cells on surgical cutaneous defect.

Cell Death Dis 2018 02 7;9(2):183. Epub 2018 Feb 7.

Department of Otorhinolaryngology-Head and Neck Surgery, Biomedical Research Institute, Pusan National University School of Medicine, Pusan National University Hospital, Busan, Republic of Korea.

As tissue engineering and regenerative medicine have evolved recently, stem cell therapy has been investigated in the field of impaired wound healing. Several studies have reported that mesenchymal stem cells derived from various tissues including bone marrow and adipose tissue can exert the regenerative efficacy in the wound healing. Previously, we have demonstrated the isolation and characterization of tonsil-derived mesenchymal stem cells (TMSCs) with excellent proliferative property. In the present study, we aimed to evaluate the regenerative efficacy of TMSCs in the wound healing process. Two distinct cutaneous surgical defects were generated in the dorsum of mice. Each wound was treated with TMSCs or phosphate-buffered saline (PBS), respectively. After sacrifice, the skin and subcutaneous tissues around the surgical defect were harvested and assessed for inflammation, re-epithelialization, dermal regeneration, and granulation tissue formation. The administration of TMSCs into wound beds significantly promoted the repair of surgical defects in mice. Especially, TMSCs efficiently contributed to the attenuation of excessive inflammation in the surgical lesion, as well as the augmentation of epidermal and dermal regeneration. To elucidate the underlying mechanisms, TMSCs were analyzed for their potency in immunomodulatory ability on immune cells, stimulatory effect on the proliferation of keratinocytes, and fibroblasts, as well as the regulation of fibroblast differentiation. TMSCs inhibited the non-specific or T-cell-specific proliferation of peripheral blood mononuclear cells, as well as the M1 polarization of macrophage-like cells. Moreover, TMSCs augmented the proliferation of skin-constituting fibroblasts and keratinocytes while they suppressed the differentiation of fibroblasts into myofibroblasts. Taken together, our findings demonstrate the regenerative potential of TMSCs in wound healing process through the regulation on inflammation, proliferation, and remodeling of various skin cells, implying that TMSCs can be a promising alternative for wound repair.
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http://dx.doi.org/10.1038/s41419-017-0248-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5833728PMC
February 2018

TSH-independent release of thyroid hormones through cold exposure in aging rats.

Oncotarget 2017 Oct 3;8(52):89431-89438. Epub 2017 Aug 3.

Department of Otorhinolaryngology - Head and Neck Surgery, Pusan National University School of Medicine and Biomedical Research Institute, Pusan National University Hospital, Busan, Korea.

Thyroid function decreases and cold exposure response becomes impaired with increasing age. We investigated the age-related changes in thyroid structure and function and cold-induced changes in the thyroid activity of aging rats. Thirty-two male Sprague-Dawley rats were randomly divided into four groups (8 rats per group): young (7 months) and old (22 months) groups exposed to room temperature and cold stress. The active follicle ratio and serum free T3, T4 and TSH, and TSH receptor (TSHR) concentrations in the thyroid tissues of the rats from each group were compared. At room temperature, old rats had significantly lower active follicle ratio and free T3 and T4 concentrations than young rats. Furthermore, old rats displayed higher TSH level than young. Exposure to cold temperature led to significantly increased active colloid ratio and free T3 and T4 concentrations among old rats, but no significant differences were found among young rats. Additionally, no significant changes in the TSH and TSHR levels were observed after cold exposure in both young and old rats. Old rats have lower thyroid function than young rats under normal temperature. Aging rats are more susceptible to cold stress than young rats, and cold-induced thyroid activation occurs independently of TSH. We investigated the age-related changes in the thyroid structure and function and cold-induced changes in the thyroid activity of aging rats. Aging rats have structurally less active thyroid follicles and functionally lower thyroid hormone levels than young rats. Furthermore, old rats are more susceptible to cold stress than young rats, and cold-induced thyroid activation occurs independently of TSH.
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http://dx.doi.org/10.18632/oncotarget.19851DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5685681PMC
October 2017

Transition metal alloying effect on the phosphoric acid adsorption strength of Pt nanoparticles: an experimental and density functional theory study.

Sci Rep 2017 08 3;7(1):7186. Epub 2017 Aug 3.

Fuel Cell Research Center, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul, 02792, Republic of Korea.

The effect of alloying with transition metals (Ni, Co, Fe) on the adsorption strength of phosphoric acid on Pt alloy surfaces was investigated using electrochemical analysis and first-principles calculations. Cyclic voltammograms of carbon-supported PtM/C (M = Ni, Co, and Fe) electrocatalysts in 0.1 M HClO with and without 0.01 M HPO revealed that the phosphoric acid adsorption charge density near the onset potential on the nanoparticle surfaces was decreased by alloying with transition metals in the order Co, Fe, Ni. First-principles calculations based on density functional theory confirmed that the adsorption strength of phosphoric acid was weakened by alloying with transition metals, in the same order as that observed in the electrochemical analysis. The simulation suggested that the weaker phosphoric acid adsorption can be attributed to a lowered density of states near the Fermi level due to alloying with transition metals.
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http://dx.doi.org/10.1038/s41598-017-06812-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5543171PMC
August 2017

Indoleamine 2,3-Dioxygenase Is Not a Pivotal Regulator Responsible for Suppressing Allergic Airway Inflammation through Adipose-Derived Stem Cells.

PLoS One 2016 3;11(11):e0165661. Epub 2016 Nov 3.

Department of Otorhinolaryngology and Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, Republic of Korea.

Background: Although indoleamine 2,3-dioxygenase (IDO)-mediated immune suppression of mesenchymal stem cells (MSCs) has been revealed in septic and tumor microenvironments, the role of IDO in suppressing allergic airway inflammation by MSCs is not well documented. We evaluated the effects of adipose-derived stem cells (ASCs) on allergic inflammation in IDO-knockout (KO) asthmatic mice or asthmatic mice treated with ASCs derived from IDO-KO mice.

Methods And Findings: ASCs were injected intravenously in wild-type (WT) and IDO-KO asthmatic mice. Furthermore, asthmatic mice were injected with ASCs derived from IDO-KO mice. We investigated the immunomodulatory effects of ASCs between WT and IDO-KO mice or IDO-KO ASCs in asthmatic mice. In asthmatic mice, ASCs significantly reduced airway hyperresponsiveness, the number of total inflammatory cells and eosinophils in bronchoalveolar lavage fluid (BALF), eosinophilic inflammation, goblet hyperplasia, and serum concentrations of total and allergen-specific IgE and IgG1. ASCs significantly inhibited Th2 cytokines, such as interleukin (IL)-4, IL-5, and IL-13, and enhanced Th1 cytokine (interferon-γ) and regulatory cytokines (IL-10, TGF-β) in BALF and lung draining lymph nodes (LLNs). ASCs led to significant increases in regulatory T-cells (Tregs) and IL-10+ T cell populations in LLNs. However, the immunosuppressive effects of ASCs did not significantly differ between WT and IDO-KO mice. Moreover, ASCs derived from IDO-KO mice showed immunosuppressive effects in allergic airway inflammation.

Conclusions: IDO did not play a pivotal role in the suppression of allergic airway inflammation through ASCs, suggesting that it is not the major regulator responsible for suppressing allergic airway inflammation.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0165661PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5094728PMC
July 2017

Role of Fibroblast Growth Factor-5 on the Proliferation of Human Tonsil-Derived Mesenchymal Stem Cells.

Stem Cells Dev 2016 08 15;25(15):1149-60. Epub 2016 Jul 15.

4 Department of Physiology, School of Medicine, Pusan National University , Yangsan, Korea.

Human mesenchymal stem cells (MSCs) are a promising tool for therapeutic applications in cell-based therapy and regenerative medicine, and MSCs from the human palatine tonsils have recently been used as a new tissue source. However, the understanding of the proliferation and differentiation capacity of tonsil-derived MSCs (T-MSCs) is limited. In this study, we compared the proliferative potential of T-MSCs with those of bone marrow MSCs (BM-MSCs) and adipose tissue-derived MSCs (A-MSCs). Additionally, we investigated the underlying mechanism of T-MSC function. We showed that T-MSCs proliferated faster than A-MSCs and BM-MSCs in methylthiazolyl diphenyl-tetrazolium (MTT) assays, cell count assays, and cell cycle distribution analyses. DNA microarray and real-time PCR analyses revealed that the expression of fibroblast growth factor-5 (FGF5) was significantly elevated in T-MSCs compared with those in A-MSCs and BM-MSCs. Cell growth curves showed a difference in cell growth between untreated cells and siFGF5-treated T-MSCs. The administration of recombinant human FGF5 (rhFGF5) to the cells transfected with siFGF5 led to a significant increase in the proliferation rates. The administration of rhFGF5 to T-MSCs led to an increase in the levels of phosphorylated ERK1/2. However, treatment with siFGF5 resulted in an overall decrease in the level of phosphorylated ERK1/2. The osteogenic differentiation of T-MSCs was reduced following siFGF5 transfection, and it recovered to near-normal levels when rhFGF5 was added. These findings indicate that T-MSCs show significantly higher proliferative potential compared with those of BM-MSCs and A-MSCs. FGF5 facilitates cell proliferation through ERK1/2 activation, and it influences the osteogenic differentiation of T-MSCs.
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http://dx.doi.org/10.1089/scd.2016.0061DOI Listing
August 2016

Decellularization of Human Nasal Septal Cartilage for the Novel Filler Material of Vocal Fold Augmentation.

J Voice 2017 Jan 5;31(1):127.e1-127.e6. Epub 2016 Feb 5.

Department of Otorhinolaryngology-Head and Neck Surgery, Pusan National University School of Medicine and Biomedical Research Institute, Pusan National University, Busan, Republic of Korea. Electronic address:

Objectives: The clinical application of allogenic and/or xenogenic cartilage for vocal fold augmentation requires to remove the antigenic cellular component. The objective of this study was to assess the effect of cartilage decellularization and determine the change in immunogenicity after detergent treatment in human nasal septal cartilage flakes made by the freezing and grinding method.

Methods: Human nasal septal cartilages were obtained from surgical cases. The harvested cartilages were treated by the freezing and grinding technique. The obtained cartilage flakes were treated with 1% Triton X-100 or 2% sodium dodecyl sulfate (SDS) for decellularization of the cartilage flakes. Hematoxylin and eosin stain (H&E stain), surface electric microscopy, immunohistochemical stain for major histocompatibility complex I and II, and ELISA for DNA contents were performed to assess the effect of cartilage decellularization after detergent treatment.

Results: A total of 10 nasal septal cartilages were obtained from surgical cases. After detergent treatment, the average size of the cartilage flakes was significantly decreased. With H&E staining, the cell nuclei of decellularized cartilage flakes were not observed. The expression of major histocompatibility complex (MHC)-I and II antigens was not identified in the decellularized cartilage flakes after treatment with detergent. DNA content was removed almost entirely from the decellularized cartilage flakes.

Conclusion: Treatment with 2% SDS or 1% Triton X-100 for 1 hour appears to be a promising method for decellularization of human nasal septal cartilage for vocal fold augmentation.
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http://dx.doi.org/10.1016/j.jvoice.2015.12.013DOI Listing
January 2017

Isolation and Localization of Mesenchymal Stem Cells in Human Palatine Tonsil by W5C5 (SUSD2).

Cell Physiol Biochem 2016 8;38(1):83-93. Epub 2016 Jan 8.

Department of Otorhinolaryngology-Head and Neck Surgery, Pusan National University School of Medicine and Biomedical Research Institute, Pusan National University, Busan, Korea.

Background/aims: Although tonsil-mesenchymal stem cells (T-MSCs) have been studied as a new autologous or homologous source of MSCs, research on specific markers of MSCs and localization for purified T-MSC isolation has not yet been reported. This study investigates the expression of W5C5 (SUSD2) in tonsil stromal cells and the colony-forming ability and differentiation potential of W5C5+ cells to determine the usefulness of W5C5+ MSCs as a marker that can be used for the purification of T-MSCs. In addition, the location of W5C5+ cells expressed in the tonsil tissues is examined.

Methods: T-MSCs were isolated from the tonsillar tissues of 12 patients undergoing tonsillectomy. The colony-forming ability, surface markers, proliferation potential, and differentiation capacities of purified W5C5+ MSCs, W5C5- MSCs, and unselected T-MSCs were evaluated. The location of the W5C5+ cells in the tonsillar tissues was also investigated by immunohistochemistry.

Results: W5C5 was expressed in 2.5±0.4% of fresh human tonsil stromal cells. W5C5+ cells formed many colonies, but W5C5- cells did not form any colonies. The colony-forming number of W5C5+ cells (74.4 ± 9.8) was significantly higher than that of unselected tonsil stromal cells (23.6 ± 3.7). However, the differences in proliferation potential, surface marker expression, and differentiation potential between W5C5+ T-MSCs and unselected T-MSCs were not significant. W5C5+ cells were identified in the perivascular area around the blood vessels.

Conclusion: W5C5+ T-MSCs possessed typical MSC properties with high colony-forming efficiency, and niches of W5C5+ T-MSCs were located in the perivascular area of tonsil tissues. These findings suggest that W5C5 is a useful single marker for the isolation of purified T-MSCs.
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http://dx.doi.org/10.1159/000438611DOI Listing
October 2016

Green synthesis of carbon-supported nanoparticle catalysts by physical vapor deposition on soluble powder substrates.

Sci Rep 2015 Sep 18;5:14245. Epub 2015 Sep 18.

Fuel Cell Research Center, Korea Institute of Science and Technology (KIST), Seoul 136-791, Republic of Korea.

Metal and metal oxide nanoparticles (NPs) supported on high surface area carbon (NP/Cs) were prepared by the physical vapor deposition of bulk materials on an α-D-glucose (Glu) substrate, followed by the deposition of the NPs on carbon supports. Using Glu as a carrier for the transport of NPs from the bulk materials to the carbon support surfaces, ultrafine NPs were obtained, exhibiting a stabilizing effect through OH moieties on the Glu surfaces. This stabilizing effect was strong enough to stabilize the NPs, but weak enough to not significantly block the metal surfaces. As only the target materials and Glu are required in our procedure, it can be considered environmentally friendly, with the NPs being devoid of hazardous chemicals. Furthermore, the resulting NP/Cs exhibited an improvement in activity for various electrochemical reactions, mainly attributed to their high surface area.
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http://dx.doi.org/10.1038/srep14245DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4585564PMC
September 2015

Effects of donor age, long-term passage culture, and cryopreservation on tonsil-derived mesenchymal stem cells.

Cell Physiol Biochem 2015 27;36(1):85-99. Epub 2015 Apr 27.

Department of Otorhinolaryngology-Head and Neck Surgery, Pusan National University School of Medicine and Biomedical Research Institute, Pusan National University, Busan, Korea.

Objectives: Human mesenchymal stem cells (MSCs) are efficacious in various cellular therapeutic applications and have been isolated from several tissues. Recent studies have reported that human tonsil tissue contains a new source of progenitor cells, potentially applicable for cell-based therapies. Information about the effects of donor age, long-term passage and cryopreservation are essential for clinical applications and cell-based therapies. Therefore, the authors investigated how the morphology, cell-surface markers, proliferation potential and differentiation capacity of tonsil-derived MSCs (T-MSCs) were affected by donor age, long-term passage, and cryopreservation.

Materials And Methods: T-MSCs were isolated from tonsillar tissue of 20 patients undergoing tonsillectomy. Authors evaluated the effects of donor-age, long-term passage, and cryopreservation on the morphology, surface markers, proliferation potential and differentiation capacities of T-MSCs.

Results: T-MSCs exhibited a fibroblast-like, spindle-shaped appearance. There were no significant morphological differences according to donor age, long-term passage or cryopreservation. T-MSCs isolated from donors of various ages were positive for markers CD90, CD44, and CD73, but negative for CD45, CD31, and HLA-DR. There were no significant differences in the expression of positive and negative surface markers as a function of donor age, long-term passage and cryopreservation. T-MSCs from different donor age groups showed similar proliferation potentials after passage 2. After long-term passage and cryopreservation, there were no significant morphological differences. Cryopreservation did not affect the proliferation potential of T-MSCs, but there was a significant decrease in the proliferation potential in long-term passage T-MSCs (passage 15). The effect of donor age, long-term passage and cryopreservation on the in vitro adipogenic, osteogenic, and chondrogenic differentiation potential of T-MSCs was not significant.

Conclusion: The effect of donor age, long-term passage culture, and cryopreservation on T-MSC properties are negligible, except for the proliferation capacity of long-term cultured T-MSCs. Therefore, T-MSCs are considered to be promising MSCs that can be used as future alternative sources for autologous or allogenic MSCs.
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http://dx.doi.org/10.1159/000374055DOI Listing
February 2016

Third-body effects of native surfactants on Pt nanoparticle electrocatalysts in proton exchange fuel cells.

Chem Commun (Camb) 2015 Feb;51(14):2968-71

Fuel Cell Research Center, Korea Institute of Science and Technology (KIST), Seoul 136-791, Republic of Korea.

The residual surfactant organic molecules on electrocatalysts are expected to enhance the tolerance to specific anion adsorption, whereas the surfactants have been generally regarded as contaminants that block active surfaces. In this study, the Pt nanoparticles with adsorbed surfactants were prepared, and their electrochemical characteristics at various phosphoric acid concentrations were studied by the half-cell test. The third-body effect was experimentally confirmed by the single-cell test with a phosphoric acid-doped polybenzimidazole membrane.
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http://dx.doi.org/10.1039/c4cc09019eDOI Listing
February 2015

Differential expression levels of plasma-derived miR-146b and miR-155 in papillary thyroid cancer.

Oral Oncol 2015 Jan 23;51(1):77-83. Epub 2014 Oct 23.

Department of Otorhinolaryngology-Head and Neck Surgery, Pusan National University School of Medicine and Medical Research Institute, Busan 602-739, Republic of Korea. Electronic address:

Background: Specific circulating microRNAs (miRNAs) in each organ may contribute to the diagnosis and prognosis in some cancers. miRNA from papillary thyroid cancer (PTC) may be released into the bloodstream. This study was performed to detect miRNAs in the plasma and estimate their diagnostic usefulness for discriminating between benign and malignant lesions.

Methods: Patients who underwent thyroidectomy for benign thyroid nodules or PTC were enrolled in this study. The patients were divided into three groups: benign, PTC without lymph node metastasis (LNM), and PTC with LNM. The levels of miR-146b, miR-221, miR-222, and miR-155miRNA expression in blood samples before surgery were evaluated.

Results: Of 89 patients enrolled in this study, 19 and 70 had benign lesions (21.3%) and PTC (78.7%), respectively. The mean levels of miR-146b and miR-155 expression were higher in the PTC group than the benign group. For discrimination between benign and PTC lesions, the area under the ROC curve (AUC) for miR-146b was 0.649 with 61.4% sensitivity and 57.9% specificity. The AUC for miR-155 was 0.695 with 74.3% sensitivity and 63.2% specificity (P<0.05). The levels of miR-146b, miR-221, and miR-222 were slightly higher in the N1 group than the N0 group. The levels of miR-146b, miR-155, and miR-222 increased in proportion to tumor size.

Conclusions: miR-146b and miR-155 helped to discriminate between benign and malignant lesions. Circulating miRNA is likely a useful alternate serological marker for PTC. This preliminary study suggested that circulating miRNAs may be useful as follow-up tools as well as diagnostic tools.
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http://dx.doi.org/10.1016/j.oraloncology.2014.10.006DOI Listing
January 2015

Adipose-derived stem cells ameliorate allergic airway inflammation by inducing regulatory T cells in a mouse model of asthma.

Mediators Inflamm 2014 26;2014:436476. Epub 2014 Aug 26.

Department of Otorhinolaryngology and Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Beom-eo li, Mul-geum eup, Yang-san si, Gyeongsangnam-do, Yangsan 626-770, Republic of Korea.

Although several studies have demonstrated that mesenchymal stem cells derived from adipose tissue (ASCs) can ameliorate allergic airway inflammation, the immunomodulatory mechanism of ASCs remains unclear. In this study, we investigated whether regulatory T cells (Tregs) induction is a potential mechanism in immunomodulatory effects of ASCs on allergic airway disease and how these induced Tregs orchestrate allergic inflammation. Intravenous administration of ASCs significantly reduced allergic symptoms and inhibited eosinophilic inflammation. Airway hyperresponsiveness, total immune cell and eosinophils in the bronchoalveolar lavage fluid, mucus production, and serum allergen-specific IgE and IgG1 were significantly reduced after ASCs administration. ASCs significantly inhibited Th2 cytokines (IL-4, IL-5, and IL-13) and enhanced Th1 cytokine (IFN-γ) and regulatory cytokines (IL-10 and TGF-β) in the bronchoalveolar lavage fluid and lung draining lymph nodes. Furthermore, levels of IDO, TGF-β, and PGE2 were significantly increased after ASCs administration. Interestingly, this upregulation was accompanied by increased Treg populations. In conclusion, ASCs ameliorated allergic airway inflammation and improved lung function through the induction of Treg expansion. The induction of Treg by ASCs involves the secretion of soluble factors such as IDO, TGF-β, and PGE2 and Treg might be involved in the downregulation of Th2 cytokines and upregulation of Th1 cytokines production.
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http://dx.doi.org/10.1155/2014/436476DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4160627PMC
June 2015

Metformin: a potential drug to treat hyperpigmentation disorders.

J Invest Dermatol 2014 Oct;134(10):2488-2491

Division of Graduate Medical Sciences, Department of Dermatology, Boston University School of Medicine, Boston, Massachusetts, USA. Electronic address:

Hyperpigmentation disorders are generally difficult to treat because of the limited availability of effective therapeutics with minimal side effects. In this issue, Lehraiki et al. report that metformin, an antidiabetic drug, inhibited melanogenesis, in vitro and in vivo, and they suggest that metformin may be used to treat hyperpigmentation disorders. This commentary reviews the molecular mechanisms through which metformin inhibits melanogenesis and examines metformin as a potential drug to treat hyperpigmentation.
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http://dx.doi.org/10.1038/jid.2014.245DOI Listing
October 2014

Correlation of chemokine receptor CXCR4 mRNA in primary cutaneous melanoma with established histopathologic prognosticators and the BRAF status.

Melanoma Res 2014 Dec;24(6):621-5

aDivision of Graduate Medical Sciences bSchool of Public Health cBoston University School of Medicine dDepartment of Pathology eDepartment of Dermatology, Dermatopathology Section, Boston University School of Medicine, Boston, Massachusetts, USA.

Dysregulation of the chemokine receptor CXCR4 is relevant in melanoma progression, and the CXCR4/CXCL12 axis has been shown to activate cell cycle progression and malignant cell migration through stimulation of the mitogen-activated protein kinase pathway. Studies ascertaining the potential utility of CXCR4 mRNA as a prognosticator in melanoma have focused mainly on metastatic melanoma with conflicting results. In the light of this, we sought to explore the potential relationship between CXCR4 mRNA expression with established histopathologic prognosticators and BRAF status in melanoma. Archived consecutive samples (n=107) of primary cutaneous melanoma were retrieved and assessed for the following: CXCR4 mRNA (semiquantitative RT-PCR) and BRAF exon 15 status (DNA Sanger sequencing). Statistical analyses included correlation between CXCR4 mRNA levels and established histopathologic prognosticators as well as the BRAF status using univariate and multiple linear methods. Multivariable analyses revealed a significant correlation between elevated CXCR4 mRNA (low ΔCt value) and the presence of BRAF mutation (P=0.02). Absence of a brisk host response was associated with elevated CXCR4 mRNA expression (P=0.04). CXCR4 mRNA was significantly lower in AJCC stage 2 compared with stage 1 after controlling for significant clinical prognosticators (P=0.02). The association between elevated CXCR4 mRNA and absence of a brisk host response suggests that CXCR4 may be involved in regulation of the host immune response in melanoma and is a molecule of potential utility as a biomarker for recruiting melanoma patients for immunotherapy. Higher CXCR4 mRNA in patients with a BRAF mutation suggests its utility as a putative therapeutic target.
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http://dx.doi.org/10.1097/CMR.0000000000000120DOI Listing
December 2014

Protein expression of the chemokine receptor CXCR4 and its ligand CXCL12 in primary cutaneous melanoma--biomarkers of potential utility?

Hum Pathol 2014 Oct 2;45(10):2094-100. Epub 2014 Jul 2.

Dermatopathology section, Department of Dermatology, Boston University School of Medicine, Boston, MA 02118. Electronic address:

Dysregulation of the CXCR4/CXCL12 axis, relevant in melanoma progression, activates cell cycle progression and migration via stimulation of the MAPK pathway. We sought to ascertain the cooperativity of the CXCR4/CXCL12 axis with established prognosticators and BRAF status in melanoma. Samples (n = 107) of primary cutaneous melanoma were assessed for protein expression of CXCR4 and CXCL12, and molecular analyses were performed to ascertain BRAF status. Univariate analyses of CXCR4 protein showed that the proportion of CXCR4 positives was greater in melanomas with absence of mitoses (P < .0001), absence of ulceration (P = .0008), and absence of regression (P = .02). Patients presenting at shallower stages (American Joint Committee on Cancer [AJCC] 1-2) exhibited a larger proportion of CXCR4 positives (76.9%, P < .0001 and 69.0%, P = .008), whereas those at deeper stages (AJCC 3-4) exhibited a larger proportion of negatives (75.0%, P = .004 and 66.7%, P = .22). In a multivariate analysis, lower odds of CXCR4 protein expression were associated with AJCC stage 3 (odds ratio [OR]=0.16, P = .01), AJCC stage 4 (OR=0.17, P = .04), and mitoses (OR=0.21, P = .01). Univariate analyses of CXCL12 protein showed that the proportion of CXCL12 negatives was significantly smaller in melanomas with depth of at least 1 mm, absence of ulceration, and absence of vascular invasion (P < .0001 for all). CXCR4 and CXCL12 appear to be biomarkers associated with established prognosticators of good and poor clinical outcome, respectively, in primary cutaneous melanoma. A BRAF mutation does not appear to be associated with CXCR4/CXCL12 axis upregulation in primary cutaneous melanoma.
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http://dx.doi.org/10.1016/j.humpath.2014.06.018DOI Listing
October 2014

Immunomodulatory Effect of Mesenchymal Stem Cells on T Lymphocyte and Cytokine Expression in Nasal Polyps.

Otolaryngol Head Neck Surg 2014 06 13;150(6):1062-70. Epub 2014 Mar 13.

Department of Otorhinolaryngology and Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, South Korea

Objectives: Adipose tissue-derived stem cells (ASCs) have been reported to have immunomodulatory effects in various inflammatory diseases, including asthma and allergic rhinitis, through the induction of T cell anergy. Nasal polyps (NPs) are a chronic inflammatory disease in the nose and paranasal sinus characterized histologically by the infiltration of inflammatory cells, such as eosinophils or lymphocytes. This study was performed to investigate whether ASCs have immunomodulatory effects on T lymphocyte and cytokine expression in eosinophilic NPs.

Study Design: Basic science experimental study.

Setting: University tertiary care facility.

Subjects And Methods: NP specimens were obtained from 20 patients with chronic rhinosinusitis and eosinophilic NPs. ASCs were isolated and cultured from the abdominal fat of 15 subjects undergoing intra-abdominal surgery. Infiltrating cells (1 × 10(6)) were isolated from NP tissue and co-cultured with 1 × 10(5) ASCs. To determine whether ASCs affect infiltrating T lymphocyte and cytokine expression in eosinophilic NP, T lymphocyte subsets and cytokine expression were analyzed before and after ASC treatment.

Results: ASC treatment significantly decreased the proportions of CD4(+) and CD8(+) T cells. After ASC treatment, Th2 cytokine (interleukin [IL]-4 and IL-5) levels decreased significantly. In contrast, levels of Th1 (interferon-γ and IL-2) and regulatory cytokines (transforming growth factor-β and IL-10) increased significantly after ASC treatment.

Conclusions: ASCs have immunomodulatory effects in the eosinophilic inflammation of NPs, characterized by down-regulation of activated T lymphocytes and a Th2 immune response. These effects would be expected, over time, to significantly contribute to the control of eosinophilic inflammation and, possibly, growth of eosinophilic NPs.
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http://dx.doi.org/10.1177/0194599814525751DOI Listing
June 2014

Human ethmoid sinus mucosa: a promising novel tissue source of mesenchymal progenitor cells.

Stem Cell Res Ther 2014 Jan 24;5(1):15. Epub 2014 Jan 24.

Introduction: The identification of new progenitor cell sources is important for cell-based tissue engineering strategies, understanding regional tissue regeneration, and modulating local microenvironments and immune response. However, there are no reports that describe the identification and isolation of mesenchymal progenitor cells (MPCs) from paranasal sinus mucosa, and compare the properties of MPCs between tissue sources within the sinonasal cavity. We report here the identification of MPCs in the maxillary sinus (MS) and ethmoid sinus (ES). Furthermore, we contrast these MPCs in the same individuals with MPCs from two additional head and neck tissue sources of the inferior turbinate (IT) and tonsil (T).

Methods: These four MPC sources were exhaustively compared for morphology, colony-forming potential, proliferation capability, immunophenotype, multilineage differentiation potential, and ability to produce soluble factors.

Results: MS-, ES, IT-, and T-MPCs showed similar morphologies and surface phenotypes, as well as adipogenic, osteogenic, and chondrogenic differentiation capacity by immunohistochemistry and qRT-PCR for defined lineage-specific genes. However, we noted that the colony-forming potential and proliferation capability of ES-MPCs were distinctly higher than other MPCs. All MPCs constitutively, or upon stimulation, secrete large amounts of IL-6, IL-8, IL-10, IFN-γ, and TGF-β. After stimulation with TNF-α and IFN-γ, ES-MPCs notably demonstrated significantly higher secretion of IL-6 and IL-10 than other MPCs.

Conclusions: ES-MPCs may be a uniquely promising source of MPCs due to their high proliferation ability and superior capacity toward secretion of immunomodulatory cytokines.
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http://dx.doi.org/10.1186/scrt404DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4055077PMC
January 2014
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