Anti-chitinase-3-like 1 antibody attenuated atopic dermatitis-like skin inflammation through inhibition of STAT3-dependent CXCL8 expression.

BACKGROUND AND PURPOSE: Chitinase-3-like 1 (CHI3L1) causes skin inflammation in the progression of atopic dermatitis. We investigated if anti-CHI3L1 antibody could prevent the development of atopic dermatitis and its mechanisms of action. EXPERIMENTAL APPROACH: The effect of CHI3L1 antibody on phthalic anhydride-induced atopic dermatitis animal model and in vitro reconstructed human skin (RHS) model were investigated. Expression and release of atopic dermatitis-related cytokines were determined using an enzyme-linked immunosorbent assay, and RT-qPCR, STAT3 and CXCL8 signalling were measured by western blotting. KEY RESULTS: Anti-CHI3L1 antibody suppressed phthalic anhydride-induced epidermal thickening, clinical score, IgE level and infiltration of inflammatory cells, and reduced phthalic anhydride-induced inflammatory cytokines concentration. In addition, CHI3L1 antibody treatment inhibited the expression of STAT3 activity in phthalic anhydride-treated skin. It was also confirmed that CHI3L1 antibody treatment alleviated atopic dermatitis-related inflammation in the RHS model. The inhibitory effects of CHI3L1 antibody was similar or more effective compared with that of the IL-4 antibody. We further found that CHI3L1 is associated with CXCL8 by protein-association network analysis. siRNA of CHI3L1 blocked the mRNA levels of CHI3L1, IL-1ß, IL-4, CXCL8, TSLP, and the expression of CHI3L1 and p-STAT, and the level of CXCL8, whereas recombinant level of CXCL8 was elevated. Moreover, siRNA of STAT3 reduced the mRNA level of these cytokines. CHI3L1 and p-STAT3 expression correlated with the reduced CXCL8 level in the RHS in vitro model. CONCLUSION AND IMPLICATIONS: Our data demonstrated that CHI3L1 antibody could be a promising effective therapeutic drug for atopic dermatitis.

mTOR Plays an Important Role in the Stemness of Human Fetal Cartilage Progenitor Cells (hFCPCs).

BACKGROUND: Mammalian target of rapamycin (mTOR) is known to regulate self-renewal ability and potency of embryonic stem cells (ESCs) and adult stem cells in opposite manners. However, its effects vary even among adult stem cells and are not reported in fetal stem/progenitor cells. This study investigated the role of mTOR in the function of human fetal cartilage-derived progenitor cells (hFCPCs). METHODS: mTOR activity in hFCPCs was first examined via the level of phosphor-mTOR until passage 19, together with doubling time of cells and senescence-associated b-galactosidase (SA-bGal). Then, the effect of 100 nM rapamycin, the inhibitor of mTOR, was investigated on self-renewal ability, proliferation rate and osteogenic/adipogenic potential of hFCPCs in vitro. Expression of stemness genes (Oct-4, Sox2 and Nanog) and cell cycle regulators (CDK4 and Cyclin D1) was measured at mRNA or protein levels. RESULTS: mTOR activity was maintained constantly at high levels in hFCPCs until passage 19, while their proliferation rate was decreasing from 48 h at passage 13 to 70 h at passage 9 and senescent cells were observed at passage 18 (8.3 ± 1.2%) and 19 (15.6 ± 1.9%). Inhibition of mTOR in hFCPCs impaired their colony forming frequency (CFU-F) by 4 folds, while showing no change in their doubling time and expression of CDK4 and Cyclin D1. Upon mTOR inhibition, Oct4 expression decreased by 2 folds and 4 folds at the mRNA and protein levels, respectively, while that of Sox2 and Nanog did not change significantly. Finally, mTOR inhibition reduced osteogenic and adipogenic differentiation of hFCPCs in vitro. CONCLUSION: This study has shown that mTOR plays an important role in the self-renewal ability of hFCPCS but not in their proliferation, The effect of mTOR appears to be associated with Oct-4 expression and important in the osteogenic and adipogenic differentiation ability of hFCPCs.

Immunogenicity and Safety of Vaccines against Coronavirus Disease in Actively Treated Patients with Solid Tumors: A Prospective Cohort Study.

PURPOSE: We aimed to assess the humoral response to and reactogenicity of coronavirus disease 2019 (COVID-19) vaccination according to the vaccine type and to analyze factors associated with immunogenicity in actively treated solid cancer patients (CPs). Materials and Methods: Prospective cohorts of CPs, undergoing anticancer treatment, and healthcare workers (HCWs) were established. The participants had no history of previous COVID-19 and received either mRNA-based or adenovirus vector-based (AdV) vaccines as the primary series. Blood samples were collected before the first vaccination and after 2 weeks for each dose vaccination. Spike-specific binding antibodies (bAbs) in all participants and neutralizing antibodies (nAbs) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) wild-type, Delta, and Omicron variants in CPs were analyzed and presented as the geometric mean titer. RESULTS: Age-matched 20 HCWs and 118 CPs were included in the analysis. The bAb seroconversion rate and antibody concentrations after the first vaccination were significantly lower in CPs than in HCWs. After the third vaccination, antibody levels in CPs with a primary series of AdV were comparable to those in HCWs, but nAb titers against the Omicron variant did not quantitatively increase in CPs with AdV vaccine as the primary series. The incidence and severity of adverse reactions post-vaccination were similar between CPs and HCWs. CONCLUSION: CPs displayed delayed humoral immune response after SARS-CoV-2 vaccination. The booster dose elicited comparable bAb concentrations between CPs and HCWs, regardless of the primary vaccine type. Neutralization against the Omicron variant was not robustly elicited following the booster dose in some CPs, implying the need for additional interventions to protect them from COVID-19.

Granulocyte-macrophage colony-stimulating factor (GM-CSF) shows therapeutic effect on dimethylnitrosamine (DMN)-induced liver fibrosis in rats.

This study was undertaken to investigate the inhibitory effects of granulocyte-macrophage colony-stimulating factor (GM-CSF) on dimethylnitrosamine (DMN)-induced liver fibrosis in rats. Liver fibrosis was induced in Sprague-Dawley rats by injecting DMN intraperitoneally (at 10 mg/kg of body weight) daily for three consecutive days per week for 4 weeks. To investigate the effect of GM-CSF on disease onset, GM-CSF (50 µg/kg of body weight) was co-treated with DMN for 2 consecutive days per week for 4 weeks (4-week groups). To observe the effect of GM-CSF on the progression of liver fibrosis, GM-CSF was post-treated alone at 5-8 weeks after the 4 weeks of DMN injection (8-week groups). We found that DMN administration for 4 weeks produced molecular and pathological manifestations of liver fibrosis, that is, it increased the expressions of collagen type I, alpha-smooth muscle actin (α-SMA), and transforming growth factor-ß1 (TGF-ß1), and decreased peroxisome proliferator-activated receptor gamma (PPAR-γ) expression. In addition, elevated serum levels of aspartate aminotransferase (AST), total bilirubin level (TBIL), and decreased albumin level (ALB) were observed. In both the 4-week and 8-week groups, GM-CSF clearly improved the pathological liver conditions in the gross and histological observations, and significantly recovered DMN-induced increases in AST and TBIL and decreases in ALB serum levels to normal. GM-CSF also significantly decreased DMN-induced increases in collagen type I, α-SMA, and TGF-ß1 and increased DMN-induced decreases in PPAR-γ expression. In the DMN groups, survival decreased continuously for 8 weeks after DMN treatment for the first 4 weeks. GM-CSF showed a survival benefit when co-treated for the first 4 weeks but a marginal effect when post-treated for 5-8 weeks. In conclusion, co-treatment of GM-CSF showed therapeutic effects on DMN-induced liver fibrosis and survival rates in rats, while post-treatment efficiently blocked liver fibrosis.

Human Fetal Cartilage-Derived Progenitor Cells Exhibit Anti-Inflammatory Effect on IL-1ß-Mediated Osteoarthritis Phenotypes In Vitro.

BACKGROUND: In this study, we have investigated whether human fetal cartilage progenitor cells (hFCPCs) have anti-inflammatory activity and can alleviate osteoarthritis (OA) phenotypes in vitro. METHODS: hFCPCs were stimulated with various cytokines and their combinations and expression of paracrine factors was examined to find an optimal priming factor. Human chondrocytes or SW982 synoviocytes were treated with interleukin-1ß (IL-1ß) to produce OA phenotype, and co-cultured with polyinosinic-polycytidylic acid (poly(I-C))-primed hFCPCs to address their anti-inflammatory effect by measuring the expression of OA-related genes. The effect of poly(I-C) on the surface marker expression and differentiation of hFCPCs into 3 mesodermal lineages was also examined. RESULTS: Among the priming factors tested, poly(I-C) (1 µg/mL) most significantly induced the expression of paracrine factors such as indoleamine 2,3-dioxygenase, histocompatibility antigen, class I, G, tumor necrosis factor- stimulated gene-6, leukemia inhibitory factor, transforming growth factor-ß1 and hepatocyte growth factor from hFCPCs. In the OA model in vitro, co-treatment of poly(I-C)-primed hFCPCs significantly alleviated IL-1ß-induced expression of inflammatory factors such as IL-6, monocyte chemoattractant protein-1 and IL-1ß, and matrix metalloproteinases in SW982, while it increased the expression of cartilage extracellular matrix such as aggrecan and collagen type II in human chondrocytes. We also found that treatment of poly(I-C) did not cause significant changes in the surface marker profile of hFCPCs, while showed some changes in the 3 lineages differentiation. CONCLUSION: These results suggest that poly(I-C)-primed hFCPCs have an ability to modulate inflammatory response and OA phenotypes in vitro and encourage further studies to apply them in animal models of OA in the future.

Integration of ESG Information Into Individual Investors' Corporate Investment Decisions: Utilizing the UTAUT Framework.

Environmental, Social, and Governance (ESG) criteria are now considered significant, global non-financial evaluating factors of corporate value. However, no attention is given to what influences the integration of ESG information by individual investors in their investment decisions. This study first identifies different types of information investors use to make investment decisions. Risks identified in information integration in investment decision making is reviewed. Next, the Unified Theory of Acceptance and Use of Technology (UTAUT) model is used to identify individual investors' investment tendencies and the factors affecting integration of ESG information into investment decisions. Each of four categories for UTAUT innovation adoption factors (performance expectancy, effort expectancy, social influences, and facilitating conditions) are discussed in relation to how they affect individual investors' integration of ESG information. Standardization of ESG reporting and evaluation frameworks would reduce efforts to adopt ESG information and could build a strong foundation for facilitating ESG information integration. Corporates' efforts to further communicate their ESG management through their investor relations and active governmental well as non-governmental organizations' participation are recommended.

Anti-adhesive effect of chondrocyte-derived extracellular matrix surface-modified with poly-L-lysine.

After an injury, soft tissue structures in the body undergo a natural healing process through specific phases of healing. Adhesions occur as abnormal attachments between tissues and organs through the formation of blood vessels and/or fibrinous adhesions during the regenerative repair process. In this study, we developed an adhesion-preventing membrane with an improved physical protection function by modifying the surface of chondrocyte-derived extracellular matrices (CECM) with anti-adhesion function. We attempted to change the negative charge of the CECM surface to neutral using poly-L-lysine (PLL) and investigated whether it blocked fibroblast adhesion to it and showed an improved anti-adhesion effect in animal models of tissue adhesion. The surface of the membrane was modified with PLL coating (PLL 10), which neutralized the surface charge. We confirmed that the surface characteristics except for the potential difference were maintained after the modification and tested cell attachment in vitro. Adhesion inhibition was identified in a peritoneal adhesion animal model at 1 week and in a subcutaneous adhesion model for 4 weeks. Neutralized CECM (N-CECM) suppressed fibroblast and endothelial cell adhesion in vitro and inhibited abdominal adhesions in vivo. The CECM appeared to actively inhibit the infiltration of endothelial cells into the injured site, thereby suppressing adhesion formation, which differed from conventional adhesion barriers in the mode of action. Furthermore, the N-CECM remained intact without degradation for more than 4 weeks in vivo and exerted anti-adhesion effects for a long time. This study demonstrated that PLL10 surface modification rendered a neutral charge to the polymer on the extracellular matrix surface, thereby inhibiting cell and tissue adhesion. Furthermore, this study suggests a means to modify extracellular matrix surfaces to meet the specific requirements of the target tissue in preventing post-surgical adhesions.

Patient discomfort levels during instrumentation procedure using nickel-titanium files with different kinetic movements.

This study evaluated the perceived vibration, noise and discomfort levels associated with two nickel-titanium file systems with different kinetics; reciprocating motion (REC) using WaveOne Gold and continuous rotation motion (CON) using ProTaper NEXT. Forty roots with two canals from maxillary premolar and molar of 40 patients were included. Root canals were instrumented using each system for each canal. Patients were surveyed about the vibration, noise and discomfort experienced using visual analogue scale, and their preference. The responses were statistically analysed using Wilcoxon Signed-Rank test, Mann-Whitney U test and Spearman's rank correlation test at the 95% of significance level. The vibration, noise and discomfort experienced were significantly greater in REC than CON (P < 0.05). In REC, male subjects reported significantly higher vibration than female (P < 0.05). Majority respondents (72.5%) preferred the CON method. The perceived vibration, noise and discomfort were less apparent from the CON than the REC.

Low-intensity ultrasound (LIUS) differentially modulates mitochondrial reactive oxygen species (mtROS) generation by three different chemicals in PC12 cells.

We have previously shown that low-intensity ultrasound (LIUS) can modulate mitochondrial complex I activity and the generation of mitochondrial reactive oxygen species (mtROS) in PC12 cells. This study investigated the mechanism of LIUS by comparing its effect on mitochondrial dysfunction by three different pathways. LIUS was shown to reverse the effects of rotenone, a Q-site blocker, on the complex I inhibition, mtROS generation, and drop of mitochondrial membrane potential (Δψm). In contrast, common antioxidants, N-acetyl cysteine (NAC), and uric acid (UA) blocked rotenone-induced mtROS generation and Δψm drop without recovering the complex I activity, which suggested that Δψm drop is correlated with mtROS generation rather than complex I inhibition itself. Ionomycin, an ionophore for Ca2+, and L-buthionine-S,R-sulfoximine (BSO), an inhibitor of glutathione (GSH) biosynthesis, induced mtROS generation and Δψm drop without inhibiting complex I activity via different mechanisms. LIUS showed no effect on ionomycin-induced Δψm drop but showed partial inhibition on the other effects of ionomycin and BSO. These results suggest that LIUS might have redundant mechanisms but acted mainly on the complex I activity thereby modulating mtROS and Δψm levels. LIUS appeared to act on the Q-module of complex I because it showed no inhibitory effect on Zn2+, an inhibitor of the proton transporting P-module of complex I. Interestingly, pretreatment of LIUS for up to an hour in advance blocked the rotenone effect as efficiently as the co-treatment. Further studies are needed to reveal the exact mechanism of LIUS to inhibit complex I activity.

Comparative Analysis of the Expression of Chondroitin Sulfate Subtypes and Their Inhibitory Effect on Axonal Growth in the Embryonic, Adult, and Injured Rat Brains.

BACKGROUND: Chondroitin sulfate glycosaminoglycans (CS-GAGs) are the primary inhibitory GAGs for neuronal growth after central nervous system (CNS) injury. However, the inhibitory or permissive activity of CS-GAG subtypes is controversial and depends on the physiological needs of CNS tissues. In this study, we investigated the characteristics and effects of CS-GAGs on axonal growth, which was isolated from the brain cortices of normal rat embryo at E18, normal adult rat brain and injured adult rat brain. METHODS: Isolated CS-GAGs from embryo, normal adult, and injured adult rat brains were used for analyzing their effect on attachment and axonal growth using modified spot assay with dorsal root ganglion (DRG) explants and cerebellar granule neurons (CGNs). CS-GAGs were separated using high performance liquid chromatography (HPLC), and the subtypes of CS-GAGs were analyzed. RESULTS: CS-GAGs of all three groups inhibited CGN attachment and axonal growth of DRGs. However, CS-GAGs of normal adult rat brain exhibited higher inhibitory activity than those of the other groups in both assays. When subtypes of CS-GAGs were analyzed using HPLC, CS-A (4S) was the most abundant in all three groups and found in largest amount in normal adult rat brain. In contrast, unsulfated CS (CS0) and CS-C (6S) were more abundant by 3-4-folds in E18 group than in the two adult groups. CONCLUSION: When compared with the normal adult rat brain, injured rat brain showed relatively similar patterns to that of embryonic rat brain at E18 in the expression of CS subtypes and their inhibitory effect on axonal growth. This phenomenon could be due to differential expression of CS-GAGs subtypes causing decrease in the amount of CS-A and mature-type CS proteoglycan core proteins.

Engineered cartilage utilizing fetal cartilage-derived progenitor cells for cartilage repair.

The aim of this study was to develop a fetal cartilage-derived progenitor cell (FCPC) based cartilage gel through self-assembly for cartilage repair surgery, with clinically useful properties including adhesiveness, plasticity, and continued chondrogenic remodeling after transplantation. Characterization of the gels according to in vitro self-assembly period resulted in increased chondrogenic features over time. Adhesion strength of the cartilage gels were significantly higher compared to alginate gel, with the 2-wk group showing a near 20-fold higher strength (1.8 ± 0.15 kPa vs. 0.09 ± 0.01 kPa, p < 0.001). The in vivo remodeling process analysis of the 2 wk cultured gels showed increased cartilage repair characteristics and stiffness over time, with higher integration-failure stress compared to osteochondral autograft controls at 4 weeks (p < 0.01). In the nonhuman primate investigation, cartilage repair scores were significantly better in the gel group compared to defects alone after 24 weeks (p < 0.001). Cell distribution analysis at 24 weeks showed that human cells remained within the transplanted defects only. A self-assembled, FCPC-based cartilage gel showed chondrogenic repair potential as well as adhesive properties, beneficial for cartilage repair.

Low-intensity ultrasound attenuates paw edema formation and decreases vascular permeability induced by carrageenan injection in rats.

BACKGROUND: Therapeutic potential of low-intensity ultrasound (LIUS) has become evident in various musculoskeletal diseases. We have previously shown that LIUS has an inhibitory effect on local edema in various diseases including the arthritis and brain injury. In this study, we examined whether LIUS can attenuate paw edema formation vis-à-vis vascular permeability and inflammation in rats induced by carrageenan. LIUS with a frequency of 1 MHz and the intensities of 50, 100, or 200 mW/cm2 were exposed on rat paws for 10 min immediately after carrageenan injection. RESULTS: Carrageenan injection induced paw edema which was peaked at 6 h and gradually decreased nearly to the initial baseline value after 72 h. LIUS showed a significant reduction of paw edema formation at 2 and 6 h at all intensities tested. The highest reduction was observed at the intensity of 50 mW/cm2. Histological analyses confirmed that LIUS clearly decreased the carrageenan-induced swelling of interstitial space under the paw skin and infiltration of polymorphonuclear leukocytes. Moreover, Evans Blue extravasation analyses exhibited a significant decreases of vascular permeability by LIUS. Finally, immunohistochemical staining showed that expression of pro-inflammatory proteins, namely, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) induced by carrageenan injection was reduced back to the normal level after LIUS stimulation. CONCLUSIONS: These results provide a new supporting evidence for LIUS as a therapeutic alternative for the treatment of edema in inflammatory diseases such as cellulitis.

Novel short peptide tag from a bacterial toxin for versatile applications.

The specific recognition between a monoclonal antibody (mAb) and its epitope can be used in a tag system that has proved valuable in a wide range of biological applications. Herein, we describe a novel tag called RA-tag that is composed of a seven amino acid sequence (DIDLSRI) and recognized by a highly specific mAb, 47RA, against the bacterial toxin Vibrio vulnificus RtxA1/MARTXVv. By using recombinant proteins with the RA-tag at the N-terminal, C-terminal, or an internal site, we demonstrated that the tag system could be an excellent biological system for both protein purification and protein detection in enzyme-linked immunosorbent, Western blot, flow cytometry, and immunofluorescence staining analyses in Escherichia coli, mammalian cell lines, yeast, and plant. In addition, our RA-tag/47RA mAb combination showed high sensitivity and reliable affinity (KD = 5.90 × 10-8 M) when compared with conventional tags. Overall, our results suggest that the RA-tag system could facilitate the development of a broadly applicable tag system for biological research.

New staining method using methionyl-tRNA synthetase 1 antibody for brushing cytology of bile duct cancer.

BACKGROUND AND AIMS: Identifying malignant biliary strictures using endobiliary brushing cytology specimens is important for treatment decision-making and prognosis prediction. The sensitivity of brushing cytology specimens based on Papanicolaou (Pap) staining is low, which hampers accurate diagnosis of indeterminate strictures. Here, we assessed the diagnostic value of immunohistochemical (IHC) and immunofluorescence (IF) staining for methionyl-tRNA synthetase 1 (MARS1). METHODS: Endobiliary brushing cytology specimens were obtained during ERCP from 80 patients with an extrahepatic biliary stricture. Pap and MARS1 IF staining were performed on liquid-based cytology slides derived from these specimens. Sections of bile duct adenocarcinoma and normal bile duct tissue were obtained from 45 patients who underwent surgery for malignant biliary stricture, and MARS1 levels were evaluated by IHC staining. RESULTS: MARS1 IF staining was applied to brushing cytology specimens, and the results showed strong signals in malignant biliary structures but not in the negative for malignancy specimens. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 70.4%, 96.2%, 97.4%, 56.8%, and 78.8%, respectively, for conventional Pap staining and 98.1%, 96.1%, 98.1%, 96.2%, and 97.5%, respectively, for MARS1 IF (P < .0001). When IHC staining was used, MARS1 was detected in 45 bile duct adenocarcinoma sections but not in 15 normal bile duct sections. Moreover, MARS1 mRNA and protein levels were significantly higher in bile duct adenocarcinoma sections according to polymerase chain reaction and Western blot, respectively. CONCLUSIONS: The high sensitivity and accuracy of MARS1 IF staining enabled detection of malignancy in patients with indeterminate biliary stricture. Further prospective studies are needed to validate our findings. (Clinical trial registration number: KCT 0003285.).

Effects of non-paretic arm movements during bridge exercises on trunk muscle activity in stroke patients.

[Purpose] The purpose of this study was to determine the effects of non-paretic arm movement during the bridge exercise on trunk muscle activity in stroke patients. [Participants and Methods] In total, 18 stroke patients were recruited. Surface EMG electrodes were attached over the trunk muscles (rectus abdominis, RA; internal oblique, IO; erector spinae, ES), and three kinds of bridge exercises were performed: 1) 'standard' bridge, 2) bridge with unilateral isometric arm flexion, and 3) bridge with unilateral isometric arm horizontal abduction. [Results] According to the activity of the trunk muscles measured during bridge exercises, only the IO and ES showed significantly greater muscle activity during bridges with isometric arm horizontal abduction and flexion than during the standard bridge. Additionally, comparison of the paretic and non-paretic sides showed that muscle activity was higher on the paretic side. [Conclusion] This study showed that, as an exercise to heighten the activity of the trunk muscles in stroke patients, bridge exercises with accompanying non-paretic arm flexion and horizontal abduction were more effective clinically than a standard bridge.

Immunophenotype and Immune-Modulatory Activities of Human Fetal Cartilage-Derived Progenitor Cells.

We have previously reported human fetal cartilage progenitor cells (hFCPCs) as a novel source of therapeutic cells showing high proliferation and stem cell properties superior to those of adult mesenchymal stem cells (MSCs). In this study, we investigated the immunophenotype and immune-modulatory activities of hFCPCs. With institutional review board approval, hFCPCs were isolated from fetuses at 11-13 weeks of gestation. hFCPCs showed strong expression of HLA class I molecules but low or no expression of HLA class II and co-stimulatory molecules, which was not changed significantly after 4 days of IFN-γ treatment. In a mixed lymphocyte reaction (MLR), hFCPCs showed no allogeneic immune response to peripheral blood lymphocytes (PBLs) and suppressed concanavalin A (Con A)-mediated proliferation of PBLs in a dose-dependent manner. In addition, hFCPCs inhibited Con A-induced secretion of pro-inflammatory cytokines TNF-α and IFN-γ from PBLs but showed no significant decrease of secretion of IL-10, anti-inflammatory cytokine. Co-culture of hFCPCs with stimulated PBLs for 4 days resulted in a significant increase in CD4+CD25+FoxP3+ T regulatory cells (Tregs). hFCPCs expressed LIF, TGF-ß1, TSG-6, and sHLA-G5 but did not express IDO and HGF. Stimulation of hFCPCs with TNF-α for 12 h showed slight induction in the expression of LIF, TSG-6, IDO, and HGF, whereas stimulation with IFN-γ did not affect expression of any of these factors. These results suggest that hFCPCs have low allogeneic immunogenicity and immune-modulatory activity in vitro, comparable to those of MSCs. However, compared with MSCs, hFCPCs were less responsive to TNF-α and IFN-γ, and the mechanisms underlying responses to these two cell types appeared distinct.

GM-CSF Enhances Mobilization of Bone Marrow Mesenchymal Stem Cells via a CXCR4-Medicated Mechanism.

BACKGROUND: This study was conducted to investigate the effect of granulocyte-macrophage colony-stimulating factor (GM-CSF) on the mobilization of mesenchymal stem cells (MSCs) from the bone marrow (BM) into the peripheral blood (PB) in rats. METHODS: GM-CSF was administered subcutaneously to rats at 50 µg/kg body weight for 5 consecutive days. The BM and PB of rats were collected at 1, 3, and 5 days during the administration for analysis. RESULTS: Upon GM-CSF administration, the number of mononuclear cells increased rapidly at day 1 both in the BM and PB. This number decreased gradually over time in the BM to below the initial amount by day 5, but was maintained at a high level in the PB until day 5. The colony-forming unit-fibroblasts were increased in the PB by 10.3-fold at day 5 of GM-CSF administration, but decreased in the BM. Compared to GM-CSF, granulocyte-colony stimulating factor (G-CSF) stimulated lower levels of MSC mobilization from the BM to the PB. Immunohistochemical analysis revealed that GM-CSF induced a hypoxic and proteolytic microenvironment and increased C-X-C chemokine receptor type 4 (CXCR4) expression in the BM. GM-CSF added to BM MSCs in vitro dose-dependently increased CXCR4 expression and cell migration. G-CSF and stromal cell derived factor-1 (SDF-1) showed similar results in these in vitro assays. Know-down of CXCR4 expression with siRNA significantly abolished GM-CSF- and G-CSF-induced MSC migration in vitro, indicating the involvement of the SDF-1-CXCR4 interaction in the mechanism. CONCLUSION: These results suggest that GM-CSF is a useful tool for mobilizing BM MSCs into the PB.

Migration of lead and arsenic from food contact paper into a food simulant and assessment of their consumer exposure safety.

Paper is one of the most commonly used food packaging materials. During the production of packaging paper, it is possible for trace amounts of heavy metals to be incorporated as contaminants. These could migrate into food when packaging paper (food contact paper) is used for cooking, storing and eating. The aim of this study was to determine the migration of lead (Pb) and arsenic (As) from food contact paper into a food simulant and then to assess human safety through the estimated daily intake (EDI) with consumption factor. Migration tests were conducted for 310 samples using 4% acetic acid as a food simulant at 25°C for 10 min and at 95°C for 30 min. Concentrations of Pb and As in a food simulant were quantified by inductively coupled plasma mass spectrometry. LODs for Pb and As were 0.002 and 0.005 µg L-1, respectively. The migration of Pb from food contact paper ranged from not detected (ND) to 17.5 µg L-1 at 25°C for 10 min and from 0.10 to 25.6 µg L-1 at 95°C for 30 min while As ranged from ND to 0.44 µg L-1 at 25°C for 10 min and from ND to 0.87 µg L-1 at 95°C for 30 min. The migration of Pb and As determined in this study confirm that the human exposure was within safe levels based on the EDI of food contact paper compared with the provisional tolerable weekly intake for Pb of 25 µg kg-1 bw and for As of 15 µg kg-1 bw.

Release of N-nitrosamines and N-nitrosatable substances from baby bottle teats and rubber kitchen tools in Korea.

Ensuring the safety of baby bottle teats and kitchen tools made from rubber is critical. Therefore, the migration of N-nitrosamines and N-nitrosatable substances from 30 teats and 45 kitchen tools to artificial saliva was analyzed by liquid chromatography-tandem mass spectrometry. The method was validated by assessing the limits of detection (0.46-3.87 µg/kg), limits of quantification (1.38-11.73 µg/kg), and recoveries (86.3-108.6%) of seven compounds. Nitrosodimethylamine (NDMA), N-nitrosopiperidine, and N-nitrosomorpholine (NMOR) migrated from baby bottle teats at concentrations of not detected (ND) to 3.67 µg/kg. NDMA and NMOR concentrations ranged from ND to 1.72 µg/kg after migration from 45 rubber kitchen tools. N-nitrosatable substances ranged from ND to 42.16 µg/kg after migration from baby bottle teats but did not migrate from rubber kitchen tools. All tested products were considered safe for use, as N-nitrosamine and N-nitrosatable substance levels did not exceed the permitted management specifications.

Effect of joint mimicking loading system on zonal organization into tissue-engineered cartilage.

Cartilage tissue engineering typically involves the combination of a biodegradable polymeric support material with chondrocytes. The culture environment in which cell-material constructs are created and stored is an important factor. The aim of the present study was to investigate the effects of combined stimuli on cartilage zonal organization which is important to maintain cartilage functions such as lubrication and cushion. For that purpose, we developed a joint mimicking loading system which was composed of compression and shear stress. To mimic the joint loading condition, we manufactured a stimuli system that has a device similar to the shape of a femoral condyle in human knee. The fibrin/hyaluronic acid mixture with chondrocytes were dropped into support made of silicon, and placed under the device. The cartilage explants were stimulated with the joint mimicking loading system for 1 hour per day over the course of 4 weeks. The amounts of GAG and collagen in the stimulated tissue were more than that of the static cultured tissue. Cells and collagen were arranged horizontally paralleled to the surface by stimuli, while it did not happen in the control group. The results of this study suggests that mechanical load exerting in the joint play a crucial role in stimulation of extracellular matrix (ECM) production as well as its functional rearrangement.