• Molecules and Cells
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• v.41 no.11
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• pp.971-978
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• 2018

The stem cell factor (SCF)/c-KIT axis plays an important role in the hematopoietic differentiation of human pluripotent stem cells (hPSCs), but its regulatory mechanisms involving microRNAs (miRs) are not fully elucidated. Here, we demonstrated that supplementation with SCF increases the hematopoietic differentiation of hPSCs via the interaction with its receptor tyrosine kinase c-KIT, which is modulated by miR-221 and miR-222. c-KIT is comparably expressed in undifferentiated human embryonic and induced pluripotent stem cells. The inhibition of SCF signaling via treatment with a c-KIT antagonist (imatinib) during hPSC-derived hematopoiesis resulted in reductions in the yield and multi-lineage potential of hematopoietic progenitors. We found that the transcript levels of miR-221 and miR-222 targeting c-KIT were significantly lower in the pluripotent state than they were in terminally differentiated somatic cells. Furthermore, suppression of miR-221 and miR-222 in undifferentiated hPSC cultures induced more hematopoiesis by increasing c-KIT expression. Collectively, our data implied that the modulation of c-KIT by miRs may provide further potential strategies to expedite the generation of functional blood cells for therapeutic approaches and the study of the cellular machinery related to hematologic malignant diseases such as leukemia.

• Journal of Life Science
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• v.18 no.10
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• pp.1348-1354
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• 2008

mi transcription factor (MITF) is important in regulating the differentiation of mast cells. In particular, MITF regulates the transcription of the mouse mast cell-specific serine protease (mMCP)-6 gene, which is generally expressed by the connective tissue-type of mast cells. In this study, we investigated alternative isoforms of MITF that regulate transcription of the mMCP-6 gene in bone marrow-derived cultured mast cells in mice. The expression of MITF isoforms was examined by RT-PCR. We observed that MITF-A, -E, -H and -Mc were expressed by mucosal-type mast cells cultured in the presence of IL-3, whereas the connective tissue-type mast cells cultured in the presence of stem cell factor (SCF) expressed MITF-A. Overexpression of MITF isoforms increased luciferase activity through the mMCP-6 promoter in NIH-3T3 cells and elevated the level of mMCP-6 expression in the MC/9 mast cell line. Moreover, mMCP-6 expression in mast cells was significantly inhibited by the depletion of MITF. The transcriptional activity and DNA binding of MITF-A was comparable to that of MITF isoforms, including MITF-E, -H, and -Mc. Our results therefore suggest that MITF-A may be an important isoform of MITF in regulating the transcription of mMCP-6 in mouse connective tissue mast cells.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.2
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• pp.453-461
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• 2007

Drynariae Rhizoma has been used for promotes mending of the sinews and bone, tonifies the kidney for such symptoms as weak low back and knees, and stimulates the growth of hair as a tinctute for alopecia in oriental medicine. This experiment examined the effect of an acetone extracts of Drynariae Rhizomas(GSB-1), its EtoAc fraction(GB-2) and n-buOH fraction(GSB-3), on hair growth activity of the C57BL/6L mice after topical application to skin. First, We examined on hair growth activity of extracts of Drynariae Rhizomas compare to control and 1 % minoxidil groups. Second, We investigated on the number of hair follicle and mast cells after topical application of extracts of the Drynariae Rhizomas to skin for 16 day. Third, We investigated immunoreactive density of vascular endothelial growth factor(VEGF), protein kinase C-${\alpha}$(PKC-${\alpha}$) and stem(mast) cell factor(SCF) in skin of C57BL/6N mice by immunohistochemical methods. The results were as follows : Hair growth effect of acetone extracts of Drynariae Rhizomas, its EtoAc fraction and n-BuOH fraction was observed in 98 %, 96 % and 60 % in hair removed skin area in 16 day respectively, Immunoreactive density of VEGF in skin of GSB-1 group was weakly stained compare to control group in 10 day, But GSB-2 and GSB-3 groups were mildy stained in bulge and root sheath of skin. Immunolocalization of SCF antigens was observed weakly stained density in epidermis, bulge, stem cells and dermal papilla of control gruop. but in experimental group, immunoreactivity of SCF antigens was observed mildly stained density in bulge, epidermis and root sheath of GSB-1 gruop, heavily stained density in epidermis, bulge and root sheath of GSB-2 and GSB-3 groups to the hair removal skin of C57BL/6N mice on day 10. These experiment suggest that acetone extracts of Drynariae Rhizomas and its EtoAc fraction may be used for topical treatment of alopecia areata.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2001.11a
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• pp.40-46
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• 2001

The use of pluripotent stem cells has tremendous advantages for various purposes but these cell lines with proven germ-line transmission have been completely established only in the mouse. Embryonic germ (EG) cell lines are also pluripotent and undifferentiated stem cells established from primordial germ cells (PGCs). This study was conducted to establish and characterize the chicken EG cells derived from gonadal primordial germ cells. We isolated gonadal PGCs from 5.5-day-old (stage 28) White leghorn (WL) embryos and established chicken EG cells lines with EG culture medium supplemented with human stem cell factor (hSCF), murine leukemia inhibitory factor (mLIF), bovine basic fibroblast growth factor (bFGF), human interleukin-11 (hIL-11), and human insulin-like growth factor-I (hIGF-I). These cells grew continuously for 4 months (10 passages) on a feeder layer of mitotically active chicken embryonic fibroblasts. These cells were characterized by screening with the Periodic acid-Shiff＇s reaction, anti-SSEA-1 antibody, and a proliferation assay after several passages. As the results, the chicken EG cells maintained characteristics of undifferentiated stem cells as well as that of gonadal PGCs. When cultured in suspension, the chicken EG cells successfully formed an embryoid body and differentiated into a variety of cell types when re-seeded onto culture dish. The chicken EG cells were injected into blastodermal layer at stage X and dorsal aorta of recipient embryo at stage 14 (incubation of 53hrs) and produced chimeric chickens with various differentiated tissues derived from the EG cells. The germline chimeras were also successfully induced by using EG cells. Thus, Chicken EG cells will be useful for the production of transgenic chickena and for studies of germ cell differentiation and genomic imprinting.

• Proceedings of the Korean Society of Food Science and Nutrition Conference
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• 2004.11a
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• pp.110-115
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• 2004

The immature fruits of Poncirus trifoliata L. or Ponciri fructus (PF), well known as 'Jisil' in Korea, have been used against allergic diseases for generations, and still occupy an important place in traditional Oriental medicine. Anti-allergic effects of this fruit have been investigated in a few experimental models. Immunoglobulin E (IgE) is the principal immunoglobulin involved in immediate hypersensitivities and chronic allergic diseases. The effect of an aqueous extract of PF on in vivo and in vitro IgE production was investigated. PF dose-dependently inhibited the active systemic anaphylaxis and serum IgE production induced by immunization with ovalbumin, Bordetelia pertussis toxin and aluminum hydroxide gel. PF strongly inhibited interleukin 4 (IL-4)-dependent IgE production by lipopolysaccharide-stimulated murine whole spleen cells. In the case of U266 human IgE-bearing B cells, Ponciri fructus also showed an inhibitory effect on the IgE production. On the other hand, mast cell hyperplasia can be causally related with chronic inflammation. Stem cell factor (SCF), the ligand of the c-kit protooncogene product, is a major regulator and ohernoattractant of mast cells. Ponciri fiuctus (1 mg/mL) significantly inhibited the SCF-induced migration of rat peritoneal mast cells (RPMCs). RPMCs exposed to SCF (50 ng/mL) resulted in a drastic shape change with a polarized morphology while the cells exposed to Ponciri fructus (1 mg/mL) remained resting, with little or no shape alteration. The drastic morphological alteration and distribution of polymerized actin were blocked by pretreatment with Ponciri fructus. In addition, Ponciri fructus inhibited both TNF-alpha and IL-6 secretion from RPMCs stimulated with SCF. These results suggest that Ponciri fructus has an anti-allergic activity by inhibition of IgE production from B cells. These findings also provide evidence that Ponciri fructu inhibits chemotactic response and inflammatory cytokines secretion to SCF in mast cells.

• Biomedical Science Letters
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• v.13 no.2
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• pp.149-152
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• 2007

Mast cells play important roles in immune-related diseases, in particular, allergic diseases. Although 9-cis retinoic acid (9CRA) has been known as an immune regulator, its function in mast cells is not characterized well. In a previous paper, we demonstrated that 9CRA differentially decreases both CCR2 expression and the MCP-1-induced chemotactic activity of the human mast cell line, HMC-1 cells. In the present study, we examined the effects of 9CRA on the migration and expressions of inflammatory cytokines in HMC-1 cells. It was found that 9CRA significantly inhibited the migration of HMC-1 cells in response to stem cell factor (P<0.01), and it had no effect on the mRNA and protein expression of c-kit, a receptor binding to SCF. We further investigated the alternation of inflammatory cytokine expression and identified that 9CRA blocked the mRNA and protein expressions of Th2 cytokines such as interleukin (IL)-4 and IL-5. Taken together, our results demonstrate that 9CRA blocks SCF-induced cell movement and the protein secretion of IL-4 and IL-5, and this indicates that 9CRA may have anti-inflammatory effects on mast cells.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.8
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• pp.1102-1107
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• 2003

The ES cell can provide a useful system for studying differentiation and development in vitro and a powerful tool for producing transgenic animalds. To investigate the culture condition of chicken embryonic stem (CES) cells which can retain their multipotentiality or totipotency, three kinds of feeder layer cells, SNL cells, primary mice embryonic fibroblasts (PMEF) cells and primary chicken embryonic fibroblasts (PCEF) cells, were used as the feeder cells in media of DMEM supplemented with leukemia inhibitory factor (LIF), basic fibroblast growth factor (bFGF) and stem cell factor (SCF) for co-culture with blastoderm cells from stage X embryos of chicken. The alkaline phosphatase (AKP) test, differentiation experiment in vitro and chimeric chicken production were carried out. The results showed that culture on feeder layer of PMEF yielded high quality CES cell colonies. The typical CES cells clone shape revealed as follows: nested aggregation (clone) with clear edge and round surface as well as close arrangement within the clone. Strong alkaline phosphatase (AKP) reactive cells were observed in the fourth passage cells. On the other hand, the fourth passage CES cells could differentiate into various cells in the absence of feeder layer cells and LIF in vitro. The third and fourth passage cells were injected into the subgerminal cavity of recipient embryos at stage X. Of 269 Hailan embryos injected with CES cells of Shouguang Chickens, 8.2% (22/269) survived to hatching, 5 feather chimeras had been produced. This suggests that an effective culture system established in this study can promote the growth of CES cells and maintain them in the state of undifferentiated and development, which lays a solid foundation for the application of CES cells and may provide an alternative tool for genetic modification of chickens.

• Journal of Microbiology and Biotechnology
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• v.13 no.3
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• pp.422-428
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• 2003

Umbilical cord blood (UCB), a rich source of hematopoietic stem/progenitor cells, has been proposed as an alternative to bone marrow and peripheral blood for transplantation treatment. Ex vivo expansion of cord blood stem cells could make the use of cord blood transplant feasible even for adult patients. However, the optimal cytokine cocktail for expansion of stem cells is yet to be established. This study compares proliferation, apoptosis, and telomerase activities in human cord blood stem cells cultured ex vivo with FLT3 ligand (FL)/thrombopoietin (TPO) or FL/TPO/stem cell factor (SCF), with a view to determine optimal combination of cytokines. CD34+ cells were cultured in DMEM containing either FL (50 ng/ml) and TPO (10 ng/ml) (FT group) or FL (50 ng/ml), TPO (10 ng/ml) and SCF (50 ng/ml) (FTS group). The cell proliferation rate was ten times higher in the FTS group. Although cells cultured with the two different combinations of cytokines were maintained for a long term (up to 8 weeks), a large number of cells underwent differentiation during this period. Cells cultured in FTS displayed lower levels of apoptosis compared to those of the FT group during the Initial 7 days of culture. The CD34+ fraction in both groups was markedly decreased to $21-30\%$ , and only $5-6\%$ was detected at 14 days of culture. Telomerase activity detected in human CD34+ cord blood at low levels was upregulated during the early phase of culture and decreased to baseline levels in the later phase. The telomerase activity of cord blood cultured in FT was lower than that of the FTS group. Our results suggest that, on adding stem cell factors to the FT cytokines, cultured CD34+ cord blood cells display a greater degree of cell proliferation and decreased apoptosis. However, during CD34+ cord blood cell culture, a Barge number of cells undergo differentiation, indicating that more potent novel cytokines or new culture conditioning methods should be developed to maintain their ability to engraft and sustain long-term hematopoiesis.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.78-78
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• 2003

Adult stem cells can make identical copies of themselves for long periods of time. They also give rise to many differentiated mature cell types that have characteristic morphology and specialized function. Human adult stem cells are the attractive raw materials for the cell/tissue therapy, however, it is not easy to get from the adult tissues. In the present study, we tried to isolate a cell population derived from human umbilical cord vein which has been discarded after birth. The cells were isolated after treatment of the umbilical vein with collagenase or trypsin. After 3 days of culture, two kinds of cell populations were found consisting of adherent cells with endothelial cell-like and fibroblast-like morphology, respectively. When these cells were subcultured 12 times over a period of 3 months, almost cells appeared uniformly to exhibit fibroblastoid morphology which was different from that of mesenchymal stem cells obtained from human bone marrow The results of RT-PCR analyses showed distinct expression of BMP-4, oct-4, and SCF genes but not of GATA, PAX-6 and Brachyury genes. On immunohistochemical staining, the cells were negative for the von Willebrand factor(vWF), alpha-smooth muscle actin and placental alkaline phosphatase. From these observations, it is suggested that stem-like cells might be present in human umbilical cord vein.

• Preventive Nutrition and Food Science
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• v.19 no.3
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• pp.136-144
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• 2014

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. This study was conducted to evaluate the effects of Platycarya strobilacea S. et Z. (PSE) extract on mouse hair growth and to determine the mechanism of action of PSE. PSE was purchased and its antioxidant activities, such as electron donating ability, total polyphenol content, and flavonoid content were tested. Toxicity during topical treatment was determined by the CCK-8 assay, a cell viability test. Fifteen 4-week-old male C57BL/6 mice were assigned to receive one of three treatments: dimethyl sulfoxide (negative control), minoxidil (positive control) or PSE. Test materials were topically applied to the shaved dorsal skin of each mouse daily for 3 weeks. After 21 days, we observed skin tissue hair follicle morphology and length, mast cell number, and stem cell factor (SCF) expression using hematoxylin and eosin (H&E), toluidine blue, and immunohistochemical staining, respectively. Furthermore, the expression of cytokines involved in hair growth [i.e., insulin-like growth factor (IGF)-1, keratinocyte growth factor (KGF), and transforming growth factor (TGF)-${\beta}1$] was determined by PCR. PSE was found to have very high antioxidant activity. The cell viability rate of PSE-treated mice was markedly higher than that of mice in the control group. We also observed an increase in hair follicle length, strong SCF staining, and a decrease in mast cell number in the PSE group. In addition, PSE-treated mice had higher IGF-1 and KGF expression and lower TGF-${\beta}1$ expression than mice in the minoxidil-treated group. These results suggest that topical application of PSE promotes hair growth by intensifying SCF, suppressing mast cell production, and increasing hair growth-promoting cytokine expression.