- Characterization of Preadipocyte factor-1 (Pref-1) Expressing Pancreatic Cells.
-
Marie Rhee, Sun Hee Suh, Youn Joo Yang, Ji Won Kim, Sung Yoon Jeon, Oak Kee Hong, Seung Hyun Ko, Yoon Hee Choi, Bong Yun Cha, Ho Yong Son, Kun Ho Yoon
-
Korean Diabetes J. 2005;29(6):507-516. Published online November 1, 2005
-
-
-
Abstract
PDF
- BACKGROUND
Preadipocyte factor-1/Delta-like 1(Pref-1/Dlk1) is a type I membrane protein that has six epidermal growth factor (EGF)-like repeats in its extracellular and a short cytoplasmic domain. It is widely expressed in embryonic tissues, whereas its expressions were limited in adult and postnatal stage. To characterize the Pref-1 expressing cells during pancreas development and regeneration after birth, we analyzed Pref-1 expression in embryonic and adult partial pancreatectomized rat pancreas, and primary cultured neonatal pig pancreatic cells. METHODS: Whole fetuses or pieces of rat pancreas were obtained at E20. 90% partial pancreatectomy (Px) and sham operation were done using 5 week-old Sprague-Dawley rats. Experimental animals were divided into 11 groups by time of killing after surgery; 0, 1, 3, 6 and 12 hours, 1, 2, 3, 5, 7, and 14 days. All tissues were immunostained with Pref-1 and analysed by reverse transcriptase (RT)-PCR. Porcine neonatal pancreas cell clusters (NPCCs) were prepared from neonatal pigs aged 1-2 days. Cells were harvested on day 0, 3, 4, 5, 6, and 7 after dispersion. All cells were immunostained with Pref-1 and other specific cell markers such as Pan-cytokeratin (Pan-CK), vimentin (VT) and islet hormones, and confirmed by Western blot, RT-PCR and fluorescence activated cell sorting (FACS) analysis. RESULTS: In the rat embryonic pancreas at E20, Pref-1 expression was restricted only in the small branching ductules. In adult rat pancreas, Pref-1 was not expressed at all. Whereas, Pref-1 transiently expressed in the small regenerating duct cells located in foci of regeneration in Px model, then completely disappeared at day 7. The Pref-1 mRNA measured by RT-PCR was peaked at day 3 after Px and then gradually disappeared. Pref-1 expression pattern was also reproduced in monolayer cultured NPCCs. In NPCCs, protein levels of Pref-1 were peaked at day 0 to day 4 then gradually disappeared until day 7 by western blot. Most of Pref-1 expressing cells were co-stained with cytokeratin. The proportion of Pref-1 expressing cells in dispersed NPCCs were counted and isolated by FACS at 3 days after culture were 25% and then decreased over time during 7 days culture period. CONCLUSIONS: Pref-1 expression was regained in adult pancreatic cells during regeneration in vivo and in vitro and Pref-1 might be a useful marker for the pancreatic protodifferentiated cells.
- Induction of Immune Tolerance by Macrochimerism: Preliminary Study for Overcome of Islet Allograft Rejection.
-
Oak Kee Hong, Sung Joo Kim, Chung Gyu Park, Chul Woo Chung, Hyuk Sang Kwon, Yoon Hee Choi, Bong Yun Cha, Ho Yong Son, Kun Ho Yoon
-
Korean Diabetes J. 2005;29(2):112-121. Published online March 1, 2005
-
-
-
Abstract
PDF
- BACKGROUND
Recently islet transplantation(TPx) has achieved remarkable results while it is not the ultimate solution yet because of a serious shortage of human pancreases, immune rejection and recurrence of autoimmunity. Immune tolerance induction is one of the ideal way for overcome the immune rejection and recurrence of autoimmunity after islet TPx. In this study, we tested the efficacy of the mixed chimerism conducted by minimally invasive regimens on induction of immune tolerance in allogenic skin transplantation model. METHODS: Busulfan(600microgram/mouse) was administered on day -1, and 0.1 mg monoclonal antibody against CD45RB and 0.5 mg monoclonal antibody against CD154 were administered intraperitoneally on days 0, 2, 4, and 6. We gave the C57BL/6 recipients either a standard-dose(2x107 bone marrow cells/mouse; SBMT-Ig) or a high-dose(20x107 bone marrow cells/mouse; HBMT-Ig) of bone marrow from BALB/c donors. After transplantation the, C57BL/ 6 recipients received BALB/c donor skin grafting on day 0. Untreated control animals in each group, both the SBMT and HBMT mice(without busulfan) were treated with marrow cells only, and they received transplanted skin grafts from the BALB/c donor on day 0. We monitored chimerism by flow cytometry and we monitored tolerance by skin grafting. RESULTS: Chimerism was significantly increased in all the groups and it peaked on day 56 after bone marrow transplantation. On day 56, chimerism in the peripheral blood did not significantly differ between the SBMT(15.0+/-3.6%) mice and the HBMT+Ig(15.3+/-6.5%) mice. Allogenic skin transplanted on the untreated mice was invariably lost within 20 days, with a mean survival time of 10.0+/-2.5 days for the SBMT mice and 13.3+/-4.9 days for HBMT mice. The skin survival rates were significantly greater for the SBMT+Ig mice(39.0+/-36.6days) and for the HBMT+Ig mice(79.9+/-43.6 days)(HBMT+Ig vs. SBMT P=0.006: HBMT+Ig vs. SBMT+Ig P=0.0087: HBMT+Ig vs. HBMT P=0.0093). Although three of the eight(37.5%) HBMT+Ig mice showed a high skin graft survival rate >120 days, the chimerism was 3.4+/-1.3% in the peripheral blood. In the HBMT+Ig mice, chimerism was higher in the thymus(8.05+/-9.7%) than in the peripheral blood and it was significantly higher than in the thymus of the HBMT mice(0.36+/-0.5%)(P< 0.05). CONCLUSIONS: These data shows that chimerism created by minimally invasive method with high-dose bone marrow and anti-CD45RB/CD154 antibody seems promissing way for prolongation of islet allograft survival
- The Effects of High Glucose, Insulin and TGF-beta 1 on Proliferation and Differentiation of the Pancreatic Stellate Cells.
-
Oak Kee Hong, Hyuk Sang Kwon, Kyu Hyun Yeom, Marie Lee, Ji Hun Yang, Seung Hyeon Ko, Soon Jib Yoo, Hyun Sik Son, Kun Ho Yoon, Bong Yeon Cha, Kwang Woo Lee, Ho Yong Son, Sung Koo Kang
-
Korean Diabetes J. 2003;27(3):228-240. Published online June 1, 2003
-
-
-
Abstract
PDF
- BACKGROUND
Although chronic pancreatitis gives rise to fibrosis of pancreatic exocrine tissue, and type 2 diabetes is accompanied by pancreatic fibrosis, the mechanisms of fibrogenesis in the pancreas have been insufficiently studied. The activated Pancreatic stellate cells (PSC) have recently been identified in human and experimental fibrotic areas from chronic panceatitis tissues. As PSC are similar in their morphology and biochemistry to hepatic stellate cells, they are suspected to play the same role in pancreatic fibrogenesis as the hepatic stellate cells in liver fibrosis. The PSC were isolated from the rat pancreata, and mediators stimulating the proliferation and differentiation identified. METHODS: The pancreatic stellate shaped cells were isolated by a minor modification to the method described by Apte et al (ref), using a Nycodenz gradient. The isolated PSCs were confirmed by phase-contrast and by the immunofluorescence of vimentin, desmin and smooth muscle a-actin (a-SMA). The level of alpha-SMA was quantified by Western blot in the PSCs in the culture, over time, and the cell proliferation was measured by 3[H]-Thymidine incorporation. The effect of the proliferation and differentiation of the PSC were assessed in relation to D-glucose (500 mg/dL), Insulin (10 IU/mL) and TGF-beta (10 ng/mL) treatment of the culture medium. RESULTS: The stellate shaped cells from the rat pancreata grew readily in the culture. Unactivated PSCs, cultured for 3 days, had an angular appearance, contained lipid droplets, manifesting positive vitamin A autofliuorescence, and stained positively for vimentin and desmin, but negatively for alpha-SMA. Within 4~8 days of primary culturing, the PSCs were activated, the sizes and numbers of the fat droplets decreased, the cells flattened, developed long cytoplasmic extensions and expressed alpha-SMA. After 3 passages, almost 100% of the cells were positive for alpha-SMA expression, indicating a myofibroblast type of differentiation in vitro. The addition of high-glucose concentrations and insulin to the activated PSCs significantly stimulated cell proliferation (194.4+/-8.3, 175.0+/-31.0 vs. control), and when the combination of high- glucose and insulin was applied, the cell proliferation was increased to an even greater extent (247.0+/-21.8 vs. control). CONCLUSIONS: Pancreata stellate cells can be isolated, and cultured in vitro, from normal SD rats. High concentrations of glucose and insulin in culture medium activated the PSC proliferation.
|