• 대한임상검사과학회지
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• 제50권3호
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• pp.304-312
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• 2018

본 연구에서는 면역 억제 역할을 하는 것으로 알려져 있는 조절 T 세포 (regulatory T cell, Treg)의 새로운 생리학적 기능 대하여 확인해보고자 하였다. 시험관내나 동물실험에서 조절 T 세포가 분비하는 transforming growth factor ${\beta}1$ ($TGF-{\beta}1$)에 의하여 이식 직전까지 췌장섬세포의 생존률을 향상시키면서 동시에 혈당조절 기능이 향상될 수 있을 것이라는 가설이다. 이를 증명하기 위하여 마우스를 이용한 1형 당뇨병 모델을 제작한 뒤, 180 IEQ (islet equivalents)의 췌장섬세포를 동종간 이식하였다. 췌장섬세포는 이식 수술 시행 전까지 48시간 동안 $4{\times}10^6$의 Treg 세포와 함께 배양하여 Treg 유래 $TGF-{\beta}1$에 충분히 노출시킨 뒤 사용하였다. Treg 단독군, 췌장섬세포 단독군 및 Treg/islet 동시 배양군에서 각각 $TGF-{\beta}1$, IL-6 및 인슐린 분비 수준의 변화를 측정하였다. Treg/islet 동시 배양군에서 IL-6와 인슐린 분비는 증가하였고 (P<0.0005, P<0.005), 췌장섬세포 단독군과 비교하여 생존율이 향상되었다(P<0.005). 또한, 이식 후, 동시 배양된 췌장섬세포는 1형 당뇨병 마우스 모델에서 혈당 수치를 보다 효율적으로 조절하였다. 이러한 결과는 Treg 세포가 $TGF-{\beta}1$ 분비를 통하여 췌장섬세포의 기능과 생존력을 향상시킬 수 있음을 시사한다.

• 대한수의학회지
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• 제31권1호
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• pp.27-32
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• 1991

두툴상어의 췌장 내분비세포를 면역조직화학적으로 관찰하였던바, 5종의 면역반응세포들이 동정되었다. glucagon 면역반응세포는 도관의 상피간 및 췌장외분비선의 선포주위에서 한개 또는 다수의 집단으로 출현하였으며, insulin 면역반응세포는 islet의 주변부 또는 도관의 상피간에 각각 관찰되었다. somatostatin 면역반응세포는 도관의 상피간 또는 췌장외분비선의 주위에 한개 또는 집단으로 분포하였으며, 소수의 5-HT 연역반응세포는 islet의 주변부 및 췌장 외분비선의 선세포간에서 관찰되었다. BPP 면역반응세포는 극소수로 관찰되었으며, GAS/CCK외 chromogranin 면역반응세포들은 관찰되지 않았다.

• Asian-Australasian Journal of Animal Sciences
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• 제20권5호
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• pp.795-801
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• 2007

Patients with Type I diabetes mellitus have been treated with porcine insulin for several decades and pigs have recently been deemed an ideal source of microencapsulated islet cells for clinical xenotransplantation. In this study, neonatal pigs were anesthetized and sacrificed prior to a pancreatectomy. Islet cells were isolated from pancreas via collagenase digestion. Islet cells were separated and collected by hand under microscopic guidance. These cells were suspended in 1.4% sodium alginate solution and encapsulated by dropping them into 1.1% calcium chloride solution and in which the round gel in size was 250-400 ${\mu}m$ in diameter. Viability of the microencapsulated islet cells cultured in medium at $37^{\circ}C$ was assessed by MTT assay. Furthermore, insulin released in response to glucose challenge was investigated using an enzyme-linked immunosorbent assay. Secretion of insulin was low in response to the basal glucose solution (4.4 mM) in medium and was significantly higher in response to the high glucose solution (16.7 mM). The viability of microencapsulated islet cells did not differ significantly over a period of 7 days; that is, the increasing pattern of insulin concentration in the culture medium after glucose stimulation interval day was similar throughout the 7 days cultivation. In summary, experimental evidences indicated that the effects of alginate-microencapsulation prolonged survival of the neonatal porcine islets in vitro cultures and the insulin response to glucose of the islets was maintained.

• Journal of Microbiology and Biotechnology
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• 제9권2호
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• pp.150-156
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• 1999

The induction of proliferation of adult rat islets was investigated under various culture conditions. The islets were isolated from male Sprague-Dawley rats and subsequently embedded in collagen gels, which mimic the in vivo three-dimensional surroundings. During the culture period, the effects of heterologous serum (fetal bovine serum, FBS), epidermal growth factor (EGF), and retinoic acid (RA) on islet growth were examined with respect to the morphological and total DNA content changes. To investigate these changes at the cellular level, whole mount immunocytochemistry using specific antibodies for insulin and glucagon was performed. The results showed that (i) collagen gels as an extracellular matrix can maintain islets in a similar way to that in vivo, (ii) heterologous serum (FBS) had stimulatory effects on islet proliferation in a dose-dependent manner, (iii) RA had inhibitory effects on islet proliferation induced by the serum in a dose-dependent manner, (iv) EGF had weak inhibitory effects on islet proliferation induced by the serum except at the concentration of 10 nM where its effect was not significant, and (v) whole mount immunocytochemistry revealed that newly proliferated islet cells were mainly $\beta$-and $\alpha$-cells.

• 한국수의병리학회지
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• 제2권1호
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• pp.17-24
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• 1998

This is the first report of c-Jun protein expression and mRNA in a pancreatic islet in a nonobese diabetic(NOD) state mice. In this experiment NOD mice with insulin-dependent diabetes mellitus type I at age 16 weeks(n=7) just before death(n=4) were used. The control group consist of prediabetic NOD(8 weeks n=7) and ICR(8 weeks n=7 and 16 weeks n=7) mice. c-Jun positive cells in the pancreatic islet of NOD mice were localized in the same positions as a-glucagon producing cells. immunoreactivity was negative in the prediabetic NOD(8 weeks) and ICR(8 weeks and 16 weeks) mice. The number of c-Jun positive cells in mice with severe diabetic state just before death were significantly decreased when compared to NOD(16 weeks) mice. Expression of c-Jun in mRNA level was assessed by RT-PCR method. The levels of mRNA in NOD(16 weeks) mice group were elevated in total pancreatic tissues. The present results suggest that the induction of proto-oncogene protein may be of significance in assessing cell specific injury and may play a functional role between pancretic islet $\alpha$-cells and $\beta$-cells in the diabetic state.

• Archives of Plastic Surgery
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• 제48권1호
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• pp.133-143
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• 2021

Background Extensive research has been conducted on islet transplantation as a possible cure for diabetes. Islet transplantation in the liver via the portal vein has shown remarkable results, but numerous other recipient sites are currently being investigated. We aimed to show the effectiveness of using a muscle flap as a recipient site for islet transplantation. Methods Islet cells were harvested from 12 isogenic Lewis rats, and then diabetes was induced in another 12 isogenic Lewis rats by streptozotocin injection. In six rats, 3,000 islets were transplanted into gastrocnemius muscle flaps, and in the other six rats, the same number of islets were transplanted into the gastrocnemius muscle. The transplanted islet cell function between the two groups was compared by means of blood glucose tests, glucose tolerance tests, immunohistochemistry, and real-time reverse transcription polymerase chain reaction. Results In the muscle flap group, blood glucose levels significantly decreased after islet transplantation. Blood glucose levels were significantly different between the two groups at 3 weeks after transplantation. The muscle flap group showed nearly normoglycemic results upon the glucose tolerance test, whereas the muscle group was hyperglycemic. Immunohistochemical evaluation showed positive results against insulin and glucagon in biopsies of both groups, and the islet cell density was higher in the muscle flap group. There were no statistically significant differences between the two groups in real-time reverse transcription polymerase chain reaction results. Conclusions Our results suggest that muscle flaps are promising candidates for islet cell transplantation.

• IMMUNE NETWORK
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• 제12권3호
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• pp.113-117
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• 2012

FasL, perforin, $TNF{\alpha}$, IL-1 and NO have been considered as effector molecule(s) leading to ${\beta}$-cell death in autoimmune diabetes. However, the real culprit(s) of ${\beta}$-cell destruction have long been elusive despite intense investigation. Previously we have suggested $IFN{\gamma}/TNF{\alpha}$ synergism as the final effector molecules in autoimmune diabetes of NOD mice. A combination of $IFN{\gamma}$ and $TNF{\alpha}$ but neither cytokine alone, induced classical caspase-dependent apoptosis in murine insulinoma and pancreatic islet cells. $IFN{\gamma}$ treatment conferred susceptibility to $TNF{\alpha}$-induced apoptosis on otherwise resistant murine insulinoma cells by STAT1 activation followed by IRF-1 induction. Here we report that $IFN{\gamma}/TNF{\alpha}$ synergism induces apoptosis of human pancreatic islet cells. We also observed STAT1 activation followed by IRF-1 induction by $IFN{\gamma}$ treatment in human islet cells. Taken together, we suggest that $IFN{\gamma}/TNF{\alpha}$ synergism could be involved in human islet cell death in type 1 diabetes, similar to murine type 1 diabetes.

• The Korean Journal of Physiology and Pharmacology
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• 제7권4호
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• pp.211-215
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• 2003

To examine the localization pattern of phospholipase D2 (PLD2) in the pancreatic islet (the islet of Langerhans) depending on species, we conducted a morphological experiment in the rat and guinea pig. Since individual islets display a typical topography with a central core of B cell mass and a peripheral boundary of A, D, and PP cells, double immunofluorescent staining with a panel of antibodies was performed to identify PLD2-immunoreactive cells in the islets PLD2 immunoreactivity was mainly present in A and PP cells of the rat pancreatic islets. And yet, in the guinea pig, PLD2 immunoreactivity was exclusively localized in A cells, and not in PP cells. These findings suggest a possibility that PLD2 is mainly located in A cells of rodent pancreatic islets, and that the existence of PLD2 in PP cells is not universal in all species. Based on these results, it is suggested that PLD2 may play a significant role in the function of A and/or PP cells via a PLD-mediated signaling pathway.

• 생명과학회지
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• 제19권7호
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• pp.923-927
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• 2009

STZ(Streptozotocin)를 이용하여 제 1형 당뇨를 유발시킨 생쥐에게 해양심층수를 음용시켜, 혈당치의 변화 및 파괴된 췌도에 미치는 영향에 대하여 연구하였다. 그 결과 수돗물을 음용시킨 생쥐에 비해서 해양심층수를 음용시킨 생쥐의 혈당이 낮아지고, 파괴되었던 췌도의 면적이 넓어졌으며, 췌도 내에 정상적인 $\beta$-세포의 수도 많아진 점으로부터, 해양심층수의 음용이 당뇨병의 증상완화에 효과가 있음이 밝혀졌다. 이러한 효과는 해양심층수에 포함된 $Mg^{2+}$의 효과인 것으로 생각되었다.

• Journal of Microbiology and Biotechnology
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• 제10권1호
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• pp.86-90
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• 2000

We have earlier reported on the cloning and identification of bft-k from an enterotoxigenic strain of Bacteroides fragilis 419, which was isolated from the blood of a Korean patient who suffered from systemic infections [4,5]. The bft-k gene encodes a 397-amino-acids metalloprotease enterotoxin, and the protein has been identified as a new isoform of B. fragilis enterotoxins (BFTs), which are cytopathic to intestinal epithelial cells to induce fluid secretion and tissue damage in ligated intestinal loops [4, 6, 18, 20]. This report describes the cloning and sequencing of the enterotoxin pahogenicity islet of B. fragilis 419 which contains the bft-k gene. the cloned enterotoxin pathogenicity islet was found to have 6,045 bp in length and to contain 120bp direct repeats near its end. In the pathogenicity islet, in addition to the BFR-K, two putative open reading frames (ORFs) were identified; (1) the t-3 gene encoding a 396-amino-acids protein of a putative metalloprotease; (2) the third gene encoding an ORF of a 59-amino-acids protein, whose function has not yet beenn characterized. The expression of the t-3 gene in B. fragilis 419 was verified by western blot analysis.