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Use of Culture to Reach Metabolically Adequate Beta-cell Dose by Combining Donor Islet Cell Isolates for Transplantation in Type 1 Diabetes Patients. Transplantation 2021; 104:e295-e302. [PMID: 32433237 DOI: 10.1097/tp.0000000000003321] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Clinical islet transplantation is generally conducted within 72 hours after isolating sufficient beta-cell mass. A preparation that does not meet the sufficient dose can be cultured until this is reached after combination with subsequent ones. This retrospective study examines whether metabolic outcome is influenced by culture duration. METHODS Forty type 1 diabetes recipients of intraportal islet cell grafts under antithymocyte globulin induction and mycophenolate mofetil-tacrolimus maintenance immunosuppression were analyzed. One subgroup (n = 10) was transplanted with preparations cultured for ≥96 hours; in the other subgroup (n = 30) grafts contained similar beta-cell numbers but included isolates that were cultured for a shorter duration. Both subgroups were compared by numbers with plasma C-peptide ≥0.5 ng/mL, low glycemic variability associated with C-peptide ≥1.0 ng/mL, and with insulin independence. RESULTS The subgroup with all cells cultured ≥96 hours exhibited longer C-peptide ≥0.5 ng/mL (103 versus 48 mo; P = 0.006), and more patients with low glycemic variability and C-peptide ≥1.0 ng/mL, at month 12 (9/10 versus 12/30; P = 0.005) and 24 (7/10 versus 6/30; P = 0.007). In addition, 9/10 became insulin-independent versus 15/30 (P = 0.03). Grafts with all cells cultured ≥96 hours did not contain more beta cells but a higher endocrine purity (49% versus 36%; P = 0.03). In multivariate analysis, longer culture duration and older recipient age were independently associated with longer graft function. CONCLUSIONS Human islet isolates with insufficient beta-cell mass for implantation within 72 hours can be cultured for 96 hours and longer to combine multiple preparations in order to reach the desired beta-cell dose and therefore result in a better metabolic benefit.
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Mueller KR, Martins KV, Murtaugh MP, Schuurman HJ, Papas KK. Manufacturing porcine islets: culture at 22 °C has no advantage above culture at 37 °C: a gene expression evaluation. Xenotransplantation 2013; 20:418-28. [PMID: 23941232 DOI: 10.1111/xen.12048] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2013] [Accepted: 07/16/2013] [Indexed: 11/28/2022]
Abstract
BACKGROUND The manufacturing process of islets includes a culture step which was originally introduced to ease the logistics of procedures in preparing the graft and transplant recipient. It has been suggested that culture at room temperature has an advantage over culture at 37 °C, in part by reducing immunogenicity via preferential elimination of contaminating cells (such as passenger leukocytes) within islets. We investigated this using islets isolated from pancreata of adult pigs. METHODS Porcine islets were isolated from three donors and cultured at 37 °C for 1 day, and then under three different conditions: 37 °C for 6 days (condition A); 22 °C for 6 days (condition B); or 22 °C for 5 days followed by 37 °C for 1 day (condition C). Recovery was assessed by DNA measurement, viability by oxygen consumption rate normalized for DNA (OCR/DNA), and gene expression by RT-PCR for a series of 9 lymphocyte markers, 11 lymphokines and chemokines, and 14 apoptotic and stress markers. RESULTS Post-culture islet recoveries were similar for the three culture conditions. Average OCR/DNA values were 129-159 nmol/min·mgDNA before culture, and 259-291, 204-212, and 207-228 nmol/min·mgDNA, respectively, for culture under conditions A, B, and C, respectively. Irrespective of culture condition, examined gene expression in all three series of lymphocyte markers, lymphokines and chemokines, and apoptotic and stress markers manifested a statistically significant decrease upon culture for 7 days. This decrease was most dramatic for condition A: in particular, most of lymphocyte markers showed a >10-fold reduction and also six markers in the lymphokine and chemokine series; these reductions are consistent with the elimination of immune cells present within islets during culture. The reduction was less for apoptotic and stress markers. For culture under condition B, the reduction in gene expression was less, and culture under condition C resulted in gene expression levels similar to those under condition A: this indicates that 24 h at 37 °C is sufficient to re-equilibrate gene expression levels from those in islets cultured at 22 °C to those in islets cultured at 37 °C. Results were consistent among the preparations from the three donors. CONCLUSIONS Culture of porcine islets at 37 °C provides benefits over culture at 22 °C with respect to OCR/DNA outcomes and reduced expression of genes encoding lymphocyte markers, lymphokines and chemokines, and markers for apoptosis and stress.
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Affiliation(s)
- Kate R Mueller
- Department of Surgery, Schulze Diabetes Institute, University of Minnesota, Minneapolis, MN, USA
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3
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Simulated microgravity combined with polyglycolic acid scaffold culture conditions improves the function of pancreatic islets. BIOMED RESEARCH INTERNATIONAL 2013; 2013:150739. [PMID: 24024182 PMCID: PMC3758870 DOI: 10.1155/2013/150739] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 06/01/2013] [Accepted: 06/16/2013] [Indexed: 01/13/2023]
Abstract
The in vitro culture of pancreatic islets reduces their immunogenicity and prolongs their availability for transplantation. Both simulated microgravity (sMG) and a polyglycolic acid scaffold (PGA) are believed to confer advantages to cell culture. Here, we evaluated the effects of sMG combined with a PGA on the viability, insulin-producing activity and morphological alterations of pancreatic islets. Under PGA-sMG conditions, the purity of the islets was ≥85%, and the islets had a higher survival rate and an increased ability to secrete insulin compared with islets cultured alone in the static, sMG, or PGA conditions. In addition, morphological analysis under scanning electron microscopy (SEM) revealed that the PGA-sMG treatment preserved the integral structure of the islets and facilitated islet adhesion to the scaffolds. These results suggest that PGA-sMG coculture has the potential to improve the viability and function of islets in vitro and provides a promising method for islet transplantation.
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Watanabe M, Yamashita K, Suzuki T, Kamachi H, Kuraya D, Koshizuka Y, Ogura M, Yoshida T, Aoyagi T, Fukumori D, Shimamura T, Okimura K, Maeta K, Miura T, Sakai F, Todo S. ASKP1240, a fully human anti-CD40 monoclonal antibody, prolongs pancreatic islet allograft survival in nonhuman primates. Am J Transplant 2013; 13:1976-88. [PMID: 23841873 DOI: 10.1111/ajt.12330] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Revised: 05/08/2013] [Accepted: 05/10/2013] [Indexed: 01/25/2023]
Abstract
A strategy for inhibiting CD40 has been considered as an alternative approach for immunosuppression because of undesirable effects of anti-CD154 monoclonal antibodies (mAbs). Previously, we demonstrated that ASKP1240, which is a fully human anti-CD40 mAb, significantly prolonged kidney and liver allograft survival in cynomolgus monkeys without causing thromboembolic complications. Herein, we evaluated the effect of ASKP1240 on pancreatic islet transplantation (PITx) in cynomolgus monkeys. Diabetes was induced by total pancreatectomy, and islet allografts were transplanted into the liver. Following PITx (8201-12 438 IEQ/kg), blood glucose levels normalized promptly in all animals. Control islet allografts were rejected within 9 days (n = 3), whereas ASKP1240 (10 mg/kg) given on postoperative days 0, 4, 7, 11 and 14 (induction treatment, n = 5) significantly prolonged graft survival time (GST) to >15, >23, 210, 250 and >608 days, respectively. When ASKP1240 (5 mg/kg) was administered weekly thereafter up to post-PITx 6 months (maintenance treatment, n = 4), GST was markedly prolonged to >96, >115, 523 and >607 days. During the ASKP1240 treatment period, both anti-donor cellular responses and development of anti-donor antibodies were abolished, and no serious adverse events were noted. ASKP1240 appears to be a promising candidate for immunosuppression in clinical PITx.
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Affiliation(s)
- M Watanabe
- First Department of Surgery, Graduate School of Medicine, Hokkaido University, Sapporo, Japan
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Avgoustiniatos ES, Scott WE, Suszynski TM, Schuurman HJ, Nelson RA, Rozak PR, Mueller KR, Balamurugan AN, Ansite JD, Fraga DW, Friberg AS, Wildey GM, Tanaka T, Lyons CA, Sutherland DER, Hering BJ, Papas KK. Supplements in human islet culture: human serum albumin is inferior to fetal bovine serum. Cell Transplant 2012; 21:2805-14. [PMID: 22863057 DOI: 10.3727/096368912x653138] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Culture of human islets before clinical transplantation or distribution for research purposes is standard practice. At the time the Edmonton protocol was introduced, clinical islet manufacturing did not include culture, and human serum albumin (HSA), instead of fetal bovine serum (FBS), was used during other steps of the process to avoid the introduction of xenogeneic material. When culture was subsequently introduced, HSA was also used for medium supplementation instead of FBS, which was typically used for research islet culture. The use of HSA as culture supplement was not evaluated before this implementation. We performed a retrospective analysis of 103 high-purity islet preparations (76 research preparations, all with FBS culture supplementation, and 27 clinical preparations, all with HSA supplementation) for oxygen consumption rate per DNA content (OCR/DNA; a measure of viability) and diabetes reversal rate in diabetic nude mice (a measure of potency). After 2-day culture, research preparations exhibited an average OCR/DNA 51% higher (p < 0.001) and an average diabetes reversal rate 54% higher (p < 0.05) than clinical preparations, despite 87% of the research islet preparations having been derived from research-grade pancreata that are considered of lower quality. In a prospective paired study on islets from eight research preparations, OCR/DNA was, on average, 27% higher with FBS supplementation than that with HSA supplementation (p < 0.05). We conclude that the quality of clinical islet preparations can be improved when culture is performed in media supplemented with serum instead of albumin.
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Jahansouz C, Jahansouz C, Kumer SC, Brayman KL. Evolution of β-Cell Replacement Therapy in Diabetes Mellitus: Islet Cell Transplantation. J Transplant 2011; 2011:247959. [PMID: 22013505 PMCID: PMC3195999 DOI: 10.1155/2011/247959] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2011] [Accepted: 08/08/2011] [Indexed: 12/12/2022] Open
Abstract
Diabetes mellitus remains one of the leading causes of morbidity and mortality worldwide. According to the Centers for Disease Control and Prevention, approximately 23.6 million people in the United States are affected. Of these individuals, 5 to 10% have been diagnosed with Type 1 diabetes mellitus (T1DM), an autoimmune disease. Although it often appears in childhood, T1DM may manifest at any age, leading to significant morbidity and decreased quality of life. Since the 1960s, the surgical treatment for diabetes mellitus has evolved to become a viable alternative to insulin administration, beginning with pancreatic transplantation. While islet cell transplantation has emerged as another potential alternative, its role in the treatment of T1DM remains to be solidified as research continues to establish it as a truly viable alternative for achieving insulin independence. In this paper, the historical evolution, procurement, current status, benefits, risks, and ongoing research of islet cell transplantation are explored.
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Affiliation(s)
- Cyrus Jahansouz
- School of Medicine, University of Virginia, Charlottesville, VA 22102, USA
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Zhao M, Song C, Zhang W, Hou Y, Huang R, Song Y, Xie W, Shi Y, Song C. The three-dimensional nanofiber scaffold culture condition improves viability and function of islets. J Biomed Mater Res A 2010; 94:667-72. [PMID: 20336763 DOI: 10.1002/jbm.a.32624] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Significant problems existing in the islet transplantation include a poor survival ability of the islet cells cultured under static conditions in vitro, decreased secretion function, and limited transplantation efficiency. In this study, we cocultured the three-dimensional (3D) self-assembling peptide nanofiber hydrogel scaffold with the islets from adult Wistar rats. The nanofiber scaffold constructed a 3D environment for the islets culture. The results of DTZ staining showed that the purity of the islets in the scaffold was >80%. The result of the fluorescent staining with AO-PI demonstrated that the viability of the islets in the 3D culture environment (within scaffold) was greater than those in the two-dimensional (2D) culture environment (without scaffold). The islets encapsulated in the 3D peptide nanofiber scaffold exhibited better secretion function. The insulin releasing index in the 3D group was remarkably higher than that in the 2D group. By scanning electron microscopy, it was observed that the 3D self-assembling peptide nanofiber hydrogel scaffold formed a nano scale fiber with a geometric form and the islets were encapsulated in this scaffold. Our research demonstrated that this nanofiber scaffold provided a favorable 3D environment for the islets to be cultured in vitro and then improve the secretion function and prolong the survival time of the islet in vitro.
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Affiliation(s)
- Ming Zhao
- The Key Laboratory of Cell Transplantation of Ministry of Health and Department of General Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin, China
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Ståhle MU, Brandhorst D, Korsgren O, Knutson F. Pathogen inactivation of human serum facilitates its clinical use for islet cell culture and subsequent transplantation. Cell Transplant 2010; 20:775-81. [PMID: 21054939 DOI: 10.3727/096368910x539056] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Serum is regarded as an essential supplement to promote survival and growth of cells during culture. However, the potential risk of transmitting diseases disqualifies the use of serum for clinical cell therapy in most countries. Hence, most clinical cell therapy programs have replaced human serum with human serum albumin, which can result in inferior quality of released cell products. Photochemical treatment of different blood products utilizing Intercept® technology has been shown to inactivate a broad variety of pathogens of RNA and DNA origin. The present study assesses the feasibility of using pathogen-inactivated, blood group-compatible serum for use in human pancreatic islet culture. Isolated human islets were cultured at 37°C for 3-4 days in CMRL 1066 supplemented with 10% of either pathogen-inactivated or nontreated human serum. Islet quality assessment included glucose-stimulated insulin release (perifusion), ADP/ATP ratio, cytokine expression, and posttransplant function in diabetic nude mice. No differences were found between islets cultured in pathogen-inactivated or control serum regarding stimulated insulin release, intracellular insulin content, and ADP/ATP ratio. Whether media was supplemented with treated or nontreated serum, islet expression of IL-6, IL-8, MCP-1, or tissue factor was not affected. The final diabetes-reversal rate of mice receiving islets cultured in pathogen-inactivated or nontreated serum was 78% and 87%, respectively (NS). As reported here, pathogen-inactivated human serum does not affect viability or functional integrity of cultured human islets. The implementation of this technology for RNA- and DNA-based pathogen inactivation should enable reintroduction of human serum for clinical cell therapy.
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Affiliation(s)
- Magnus U Ståhle
- Department of Immunology, Genetics and Pathology, Uppsala University, Sweden.
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Boyd AS, Wood KJ. Characteristics of the early immune response following transplantation of mouse ES cell derived insulin-producing cell clusters. PLoS One 2010; 5:e10965. [PMID: 20532031 PMCID: PMC2881030 DOI: 10.1371/journal.pone.0010965] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2009] [Accepted: 02/22/2010] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND The fully differentiated progeny of ES cells (ESC) may eventually be used for cell replacement therapy (CRT). However, elements of the innate immune system may contribute to damage or destruction of these tissues when transplanted. METHODOLOGY/PRINCIPAL FINDINGS Herein, we assessed the hitherto ill-defined contribution of the early innate immune response in CRT after transplantation of either ESC derived insulin producing cell clusters (IPCCs) or adult pancreatic islets. Ingress of neutrophil or macrophage cells was noted immediately at the site of IPCC transplantation, but this infiltration was attenuated by day three. Gene profiling identified specific inflammatory cytokines and chemokines that were either absent or sharply reduced by three days after IPCC transplantation. Thus, IPCC transplantation provoked less of an early immune response than pancreatic islet transplantation. CONCLUSIONS/SIGNIFICANCE Our study offers insights into the characteristics of the immune response of an ESC derived tissue in the incipient stages following transplantation and suggests potential strategies to inhibit cell damage to ensure their long-term perpetuation and functionality in CRT.
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Affiliation(s)
- Ashleigh S. Boyd
- Transplantation Research Immunology Group, Nuffield Department of Surgery, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
- NIH Center of Biomedical Research Excellence (COBRE) in Tissue Repair and Stem Cell Biology, Roger Williams Hospital, Boston University School of Medicine, Providence, Rhode Island, United States of America
| | - Kathryn J. Wood
- Transplantation Research Immunology Group, Nuffield Department of Surgery, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
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Hou Y, Song C, Xie WJ, Wei Z, Huang RP, Liu W, Zhang ZL, Shi YB. Excellent effect of three-dimensional culture condition on pancreatic islets. Diabetes Res Clin Pract 2009; 86:11-5. [PMID: 19679368 DOI: 10.1016/j.diabres.2009.07.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2009] [Revised: 07/13/2009] [Accepted: 07/16/2009] [Indexed: 11/24/2022]
Abstract
AIM Culture of cells in simulated microgravity may be potentially beneficial to the fields of cell biology and somatic cell therapy. We aimed to examine three-dimensional culture condition on pancreatic islets. METHODS Islets of Langerhans were cultured in conditions of stasis, microgravity, and microgravity with a polyglycolic acid (PGA) fibrous scaffold. After 5 days in culture, islets were transplanted into the leg muscles of streptozotocin-treated diabetic Wistar rats. The blood glucose and insulin content were determined from the tail vein blood of recipients. The grafts were then frozen, dried, and coated for analysis by scanning electron microscopy. RESULTS Grafts cultured in the three-dimensional conditions (simulated microgravity in the presence or absence of a PGA fibrous scaffold) were capable of significantly normalizing insulin production and blood glucose concentration when compared to control grafts (p<0.017). Scanning electron microscopy showed that the transplanted islets from three-dimensional culture groups demonstrated normal morphology with extracellular matrix on the surface. Islets in the PGA group exhibited well adhesion to PGA scaffolds. CONCLUSIONS The three-dimensional culture conditions significantly improved the function and morphology of the grafts. The function and morphology of the grafts in the microgravity with a scaffold group was the excellent one.
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Affiliation(s)
- Yan Hou
- Department of Biostatistics, Harbin Medical University, Harbin 150086, China
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Song C, Huang YD, Wei Z, Hou Y, Xie WJ, Huang RP, Song YM, Lv HG, Song CF. Polyglycolic Acid-islet grafts improve blood glucose and insulin concentrations in rats with induced diabetes. Transplant Proc 2009; 41:1789-93. [PMID: 19545729 DOI: 10.1016/j.transproceed.2009.01.079] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2008] [Revised: 10/25/2008] [Accepted: 01/08/2009] [Indexed: 12/01/2022]
Abstract
Pancreatic islet transplantation is a promising therapeutic treatment for type 1 diabetes mellitus. In the present study, we cocultured islets with or without a polyglycolic acid (PGA) fibrous scaffold for 5 days and transplanted the PGA-islet grafts into the leg muscles of Wistar rats with streptozotocin-induced diabetes; controls were injected with saline. The results showed that the blood glucose concentrations of the group given islets embedded with the PGA scaffold were lower than those without the scaffold or controls. On the other hand, the insulin content of the PGA-islet group was higher at all 5 time points compared with the insulin contents of the other 2 groups. After transplantation, many islets in the PGA-islet grafts showed normal morphology (as seen under the scanning electron microscope) and were surrounded by red blood cells. A fibrous extracellular matrix was visible around the PGA-islet grafts. These results demonstrated that PGA-islet grafts improved blood glucose and insulin concentrations in rats with induced diabetes.
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Affiliation(s)
- C Song
- Department of Applied Chemistry, Harbin Institute of Technology, Harbin, China
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Zhang S, Zhu C, Wu Y, Zhai W, Shi J, Song Y, Li J, Li Z, Zhang G. Brain death affects the hepatic immunogenicity of pigs. Transplant Proc 2008; 40:2159-62. [PMID: 18790180 DOI: 10.1016/j.transproceed.2008.06.053] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE The purpose of this study was to observe how the brain-death state affects the hepatic immunogenicity of pigs. MATERIALS AND METHODS Twelve healthy ChangBai pigs were allocated randomly to 2 groups: control group (n = 6) with Foley catheter balloon placed intracalvarium for 24 hours only versus brain-death group (n = 6) with brain death for 24 hours. The serum and hepatic tissues were obtained at 6, 12, and 24 hours after the initial confirmation of brain death. Tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 were determined by enzyme-linked immunosorbent assay (ELISA). The major histocompatibility complex class II (MHC-II) was determined by immunohistochemistry, and the intercellular adhesion molecule-1 (ICAM-1) mRNA and monocyte chemotactic protein-1 (MCP-1) mRNA by real-time polymerase chain reaction (PCR). RESULTS The serum TNF-alpha and IL-6, MHC-II, ICAM-1 mRNA, and MCP-1 mRNA in hepatic tissues in the brain-death group were higher than in the control group; they all increased with time. CONCLUSION Brain death increased liver immunogenicity, which may increase the immune lesion and rejection after transplantation.
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Affiliation(s)
- S Zhang
- The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
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Ihm SH, Matsumoto I, Zhang HJ, Ansite JD, Hering BJ. Effect of short-term culture on functional and stress-related parameters in isolated human islets. Transpl Int 2008; 22:207-16. [DOI: 10.1111/j.1432-2277.2008.00769.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Zhang KZ, Liu YF, Zhang JL. Protective effects of taurine on the islet viability and function in rats. Shijie Huaren Xiaohua Zazhi 2008; 16:1388-1395. [DOI: 10.11569/wcjd.v16.i13.1388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the protective effect of taurine on the islets during culturing and its mechanism in rats.
METHODS: Wistar rats were divided into 2 groups: RPMI-1640 group and taurine group. The percentage of active Caspase-9-positive cells or phospho-Akt 473-positive cells was determined by flow cytometry. The mRNA levels of tumor necrosis factor (TNF-α), interleukin-1β (IL-1β), nuclear factor-κB (NF-κB), and heme oxygenase-1 (HO-1) were evaluated by reverse transcription-polymerase chain reaction (RT-PCR) in the isolated rat islets of both groups.
RESULTS: After 1-wk culture, the percentage of Caspase-9-positive cells was significantly higher in the taurine group than that in the RPMI-1640 group (41.03% ± 4.46% vs 23.85% ± 3.09%, P < 0.05). The mRNAs of TNF-α, IL-1β, NF-κB and HO-1 were significantly expressed after the islets were isolated and purified. However, the mRNAs of TNF-α, IL-1β, NF-κB expression were decreased gradually while HO-1 expression was increased with the culturing time. After 6-h, 72-h and 1-wk culture, the mRNA levels of TNF-α, IL-1β, and NF-κB were significantly lower in the taurine group (TNF-α: 0.34 ± 0.02, 0.24 ± 0.01, 0.19 ± 0.02; IL-1β: 0.24 ± 0.09, 0.09 ± 0.01, 0.05 ± 0.01; NF-κB: 1.76 ± 0.30, 0.93 ± 0.15, 0.37 ± 0.02) than those in the RPMI-1640 group (TNF-α: 0.57 ± 0.1, 0.39 ± 0.02, 0.29 ± 0.02; IL-1β: 0.34 ± 0.02, 0.24 ± 0.01, 0.19 ± 0.02; NF-κB: 2.52 ± 0.24, 1.21 ± 0.14, 0.76 ± 0.07) (all P < 0.05), but the HO-1 mRNA level was markedly higher in the taurine group (3.74 ± 0.10, 4.33 ± 0.29, 5.28 ± 0.29 vs 2.46±0.30, 3.13 ± 0.07, 3.59 ± 0.22; all P < 0.05).
CONCLUSION: Taurine can protect the islet cells from apoptosis by inhibiting the transcription of TNF-α, IL-1β and NF-κB gene or by increasing phospho-Akt activity.
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Barbaro B, Kuechle J, Salehi P, Rodriguez L, Qi M, Gangemi A, Benedetti E, Oberholzer J. Increased albumin concentration reduces apoptosis and improves functionality of human islets. ACTA ACUST UNITED AC 2008; 36:74-81. [PMID: 18293163 DOI: 10.1080/10731190701857819] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Providing sufficient islet mass is important for successful islet transplantation. Apoptosis plays a major role in post-isolation islet cell death, and prevention of apoptosis could improve transplant outcomes. The purpose of this study was to determine whether increased concentration of human albumin (HA) in pre-transplantation culture of human islets would reduce apoptosis. Human islets were cultured in CMRL with 1.5 or 5% of HA for 24 h and apoptosis was evaluated indirectly by measuring caspase 3 activity and tetramethylrhodamine-ethyl-ester (TMRE) in dissociated islets. Islet function and viability were evaluated. Islets cultured in higher albumin concentration presented with lower caspase 3 activity (43.9 +/- 3.9 vs. 67.4 +/- 11.1, p = 0.011), and had increased insulin secretory capacity (Stimulation index 3.76 +/- 0.91 vs 1.23 +/- 0.21, p = 0.023). We conclude that an increase in albumin concentration can prevent apoptosis in isolated human islets. These findings may have implications for islet transplant outcomes.
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Affiliation(s)
- Barbara Barbaro
- Division of Transplantation, Department of Surgery, University of Illinois at Chicago, Chicago, IL 60612, USA
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Kuttler B, Wanka H, Klöting N, Gerstmayer B, Volk HD, Sawitzki B, Ritter T. Ex vivo gene transfer of viral interleukin-10 to BB rat islets: no protection after transplantation to diabetic BB rats. J Cell Mol Med 2007; 11:868-80. [PMID: 17760846 PMCID: PMC3823263 DOI: 10.1111/j.1582-4934.2007.00059.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Allogeneic and autoimmune islet destruction limits the success of islet transplantation in autoimmune diabetic patients. This study was designed to investigate whether ex vivo gene transfer of viral interleukin-10 (vIL-10) protects BioBreeding (BB) rat islets from autoimmune destruction after transplantation into diabetic BB recipients. Islets were transduced with adenoviral constructs (Ad) expressing the enhanced green fluorescent protein (eGFP), α-1 antitrypsin (AAT) or vIL-10. Transduction efficiency was demonstrated by eGFP-positive cells and vIL-10 production. Islet function was determined in vitro by measuring insulin content and insulin secretion and in vivo by grafting AdvIL-10-transduced islets into syngeneic streptozotocin (SZ)-diabetic, congenic Lewis (LEW.1 W) rats. Finally, gene-modified BB rat islets were grafted into autoimmune diabetic BB rats. Ad-transduction efficiency of islets increased with virus titre and did not interfere with insulin content and insulin secretion. Ad-transduction did not induce Fas on islet cells. AdvIL-10-transduced LEW.1 W rat islets survived permanently in SZ-diabetic LEW.1 W rats. In diabetic BB rats AdvIL-10-transduced BB rat islets were rapidly destroyed. Prolongation of islet culture prior to transplantation improved the survival of gene-modified islets in BB rats. Several genes including those coding for chemokines and other peptides associated with inflammation were down-regulated in islets after prolonged culture, possibly contributing to improved islet graft function in vivo. Islets transduced ex vivo with vIL-10 are principally able to cure SZ-diabetic rats. Autoimmune islet destruction in diabetic BB rats is not prevented by ex vivo vIL-10 gene transfer to grafted islets. Graft survival in autoimmune diabetic rats may be enhanced by improvements in culture conditions prior to transplantation.
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Affiliation(s)
- Beate Kuttler
- Institute of Physiology, Medical School, Ernst-Moritz-Arndt-University of Greifswald, Greifswalderstrasse 11c, D-17495 Karlsburg, Germany.
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Pileggi A, Cobianchi L, Inverardi L, Ricordi C. Overcoming the Challenges Now Limiting Islet Transplantation: A Sequential, Integrated Approach. Ann N Y Acad Sci 2006; 1079:383-98. [PMID: 17130583 DOI: 10.1196/annals.1375.059] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Steady improvements in islet cell processing technology and immunosuppressive protocols have made pancreatic islet transplantation a clinical reality for the treatment of patients with Type 1 diabetes mellitus (T1DM). Recent trials are showing that improved glycemic metabolic control, prevention of severe hypoglycemia, and better quality of life can be reproducibly achieved after transplantation of allogeneic islets in patients with unstable T1DM. Despite these encouraging results, challenges ahead comprise obtaining adequate islet cells for transplant, enhancing islets engraftment, sustaining beta cell mass and function over time, and defining effective immune interventions, among others. In order to overcome the current hurdles to the widespread application of islet transplantation there is a need for implementation of integrated, sequential therapeutic approaches.
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Affiliation(s)
- Antonello Pileggi
- Cell Transplant Center, Diabetes Research Institute, Miller School of Medicine, University of Miami, 1450 NW 10th Avenue (R-134), Miami, FL 33136, USA
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Xiaohui T, Wujun X, Xiaoming D, Xinlu P, Yan T, Puxun T, Xinshun F. Small Intestinal Submucosa Improves Islet Survival and Function in Vitro Culture. Transplant Proc 2006; 38:1552-8. [PMID: 16797356 DOI: 10.1016/j.transproceed.2006.02.134] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2005] [Indexed: 11/17/2022]
Abstract
INTRODUCTION Most centers maintain isolated human islet preparations in tissue culture to improve the safety as well as the practicality of islet transplantation. However, maintaining viability and recovery of islets remains a challenge. Extracellular matrix (ECM) is one of the most important components of the islet microenvironment. Reconstruction of the cell-matrix relationship seems to be necessary to sustain the structure and function of differentiated islets. Small intestinal submucosa (SIS), a natural ECM, is well known to promote wound healing, tissue remodeling, and cell growth. The purpose of this study was to evaluate recovery and function of isolated rat pancreatic islets during in vitro culture with SIS. METHODS Pancreatic islets isolated from Wistar rats following intraductal collagenase distension, mechanical dissociation, and EuroFicoll purification were cultured in plates coated with multilayer SIS (SIS-treated group) or without (standard cultured group) for 7 or 14 days in an islet culture media of RPMI 1640 (Gibco). The islets from both experimental groups were stained and counted with dithizone. Islet recovery following culture was determined by the ratio of counts after culture to the yield of islets immediately following islet isolation. The viability of the islets was assessed by a glucose challenge test with low glucose (2.7 mmol/L), high glucose (16.7 mmol/L), and high glucose solution supplemented with 50 micromol/L 3-isobutyl-1-methylxanthine solution. The apoptosis of islet cells was measured by relative quantification of histone-complexed DNA fragments by using enzyme-linked immunosorbent assay. RESULTS After 7 or 14 days of in vitro tissue culture, the recovery in SIS-treated islets group was about double of that cultured in the plates without SIS coating. In the SIS-treated group, there was no significant difference between the short- and the long-term periods of culture (95.8%+/-1.0% vs 90.8%+/-1.5%, P>.05). Following incubation with high glucose (16.7 mmol/L) solution, the insulin secretion in the SIS-treated group showed a greater increase than the control group after 14 days of culture (20.7+/-1.1 mU/L vs 11.8+/-1.1 mU/L, P<.05). When islets were placed in the high glucose solution containing IBMX, the stimulated insulin secretion was more increased in the SIS-treated than in the control group despite the duration of the culture. The calculated stimulation index of SIS-treated group was about two to three times greater than the control group. In addition, the stimulation index of the SIS-treated group remained constant regardless of short-term versus long-term culture (9.5+/-0.2 vs 10.2+/-1.2, P>.05). Much less apoptosis of islet cells occurred in the SIS-treated than in the control group. CONCLUSION Coculture of isolated rat islets with native sheetlike small intestinal submucosa seemed to build an ECM for islets providing possible biotrophic and growth factors that promote the recovery and subsequent function of islets.
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Affiliation(s)
- T Xiaohui
- Department of Renal Transplantation, First Hospital of the Xi'an Jiao Tong University, Xi'an, ShannXi, China, People's Republic of China
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Tian XH, Xue WJ, Ding XM, Pang XL, Teng Y, Tian PX, Feng XS. Small intestinal submucosa improves islet survival and function during in vitro culture. World J Gastroenterol 2006; 11:7378-83. [PMID: 16437647 PMCID: PMC4725150 DOI: 10.3748/wjg.v11.i46.7378] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM To evaluate the recovery and function of isolated rat pancreatic islets during in vitro culture with small intestinal submucosa (SIS). METHODS Pancreatic islets were isolated from Wistar rats by standard surgical procurement followed by intraductal collagenase distension, mechanical dissociation and Euroficoll purification. Purified islets were cultured in plates coated with multilayer SIS (SIS-treated group) or without multilayer SIS (standard cultured group) for 7 and 14 d in standard islet culture media of RPMI 1640. After isolation and culture, islets from both experimental groups were stained with dithizone and counted. Recovery of islets was determined by the ratio of counts after the culture to the yield of islets immediately following islet isolation. Viability of islets after the culture was assessed by the glucose challenge test with low (2.7 mmol/L) and high glucose (16.7 mmol/L) solution supplemented with 50 mmol/L 3-isobutyl-1-methylxanthine (IBMX) solution. Apoptosis of islet cells after the culture was measured by relative quantification of histone-complexed DNA fragments using ELISA. RESULTS After 7 or 14 d of in vitro tissue culture, the recovery of islets in SIS-treated group was significantly higher than that cultured in plates without SIS coating. The recovery of islets in SIS-treated group was about twice more than that of in the control group. In SIS-treated group, there was no significant difference in the recovery of islets between short- and long-term periods of culture (95.8+/-1.0% vs 90.8+/-1.5%, P>0.05). When incubated with high glucose (16.7 mmol/L) solution, insulin secretion in SIS-treated group showed a higher increase than that in control group after 14 d of culture (20.7+/-1.1 mU/L vs 11.8+/-1.1 mU/L, P<0.05). When islets were placed in high glucose solution containing IBMX, stimulated insulin secretion was higher in SIS-treated group than in control group. Calculated stimulation index of SIS-treated group was about 23 times of control group. In addition, the stimulation index of SIS-treated group remained constant regardless of short- and long-term periods of culture (9.5+/-0.2 vs 10.2+/-1.2, P>0.05). Much less apoptosis of islet cells occurred in SIS-treated group than in control group after the culture. CONCLUSION Co-culture of isolated rat islets with native sheet-like SIS might build an extracellular matrix for islets and provide possible biotrophic and growth factors that promote the recovery and subsequent function of islets.
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Affiliation(s)
- Xiao-Hui Tian
- Center of Renal Transplantation, The First Hospital of Xioan Jiaotong University, Xioan 710061, Shaanxi Province, China
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Murdoch TB, McGhee-Wilson D, Shapiro AMJ, Lakey JRT. Methods of human islet culture for transplantation. Cell Transplant 2005; 13:605-618. [PMID: 15648731 DOI: 10.3727/000000004783983602] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The ability to maintain isolated human islet preparations in tissue culture has recently been adopted by most islet transplant centers, and improves the safety as well as the practicality of islet transplantation. Maintaining islet viability and recovery, however, remains challenging in a clinical setting, due to stringent conditions required for culture. Islet culture is further complicated by the fact that islets do not form a monolayer. This review aims to clarify media, supplementation, and conditions that have been shown to be relevant to human islets, as well as to offer avenues of future research. Factors examined that may influence islet survival include base medium, glucose concentration, vitamin, inorganic ion, lipid, hormone, growth factor, amino acid, and binding protein composition and concentration, as well as culture temperature and seeding density. In addition, this article reviews novel techniques, such as coculture and matrices, that have been employed in an attempt to improve islet survival and functional viability.
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Affiliation(s)
- T B Murdoch
- Clinical Islet Transplant Program, University of Alberta, Edmonton, Alberta, Canada
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Edamura K, Nasu K, Iwami Y, Nishimura R, Ogawa H, Sasaki N, Ohgawara H. Effect of long-term culture on the expression of antigens and adhesion molecule in single porcine pancreatic endocrine cells. Xenotransplantation 2005; 12:327-32. [PMID: 15943783 DOI: 10.1111/j.1399-3089.2005.00232.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Changes in the expression of galactose (Gal) alpha1-3Gal, swine lymphocyte antigen (SLA) class II and intracellular adhesion molecule (ICAM)-1 of single porcine pancreatic endocrine (PE) cells during the culture period were investigated. METHODS Cultured porcine PE-cells were fixed in 10% buffered formalin for histological evaluation. At 1, 3, 6, 9 and 12 weeks of culture, mRNA was obtained from porcine PE-cells so that the expression of SLA class II and ICAM-1 genes could be examined by reverse transcriptase-polymerase chain reaction. RESULTS The rates of Galalpha1-3Gal and SLA class II-positive cells did not decrease during the culture period, but the rates of Galalpha1-3Gal and SLA class II strongly positive cells significantly decreased. ICAM-1-positive cells were scarcely observed during the culture period. SLA class II and ICAM-1 mRNAs were detected at 1 and 3 weeks of culture, but were not detected after 6 weeks of culture. CONCLUSIONS These results suggest that partial reduction in the expression of these antigens could be obtained by a long-term culture.
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Affiliation(s)
- Kazuya Edamura
- Laboratory of Veterinary Emergency Medicine, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan.
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Young HY, Zucker P, Flavell RA, Jevnikar AM, Singh B. Characterization of the Role of Major Histocompatibility Complex in Type 1 Diabetes Recurrence after Islet Transplantation. Transplantation 2004; 78:509-15. [PMID: 15446308 DOI: 10.1097/01.tp.0000128907.83111.c6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Major histocompatibility complex (MHC) molecules are essential determinants of beta-cell destruction in type 1 diabetes (T1D). MHC class I- or class II-null nonobese diabetic (NOD) mice do not spontaneously develop autoimmune diabetes and are resistant to adoptive transfer of disease. Both CD4+ and CD8+ T cells are associated with graft destruction after syngeneic islet transplantation. MHC molecules within the graft (i.e., on beta-cells or donor lymphocytes) may influence the interactions between antigen presenting cells and effector T cells and, therefore, the survival outcome of the graft. METHODS Donor islets from NOD mice deficient in one or both of beta2-microglobulin and class II transactivator genes were transplanted into diabetic NOD mice. Immunohistochemistry was performed to identify the phenotype of infiltrating cells and to assess graft insulin production. The presence of cytokines in the grafts was assayed by reverse transcription polymerase chain reaction. RESULTS MHC class II-null islets demonstrated rates of rejection comparable with control wild-type (wt) islets. In contrast, MHC class I- and II-null islets demonstrated indefinite survival (over 100 days). Infiltrates of both failed and surviving grafts were comprised of cytotoxic lymphocytes (CTL), helper T cells, and macrophages. Grafts also showed the presence of both Th1- and Th2-type cytokines (interleukin [IL]-2, IL-4, IL-10, and interferon-gamma), independent of graft status. CONCLUSIONS These results demonstrate the primary importance of MHC class I molecules in the pathogenesis of diabetes recurrence postislet transplantation. Conversely, MHC class II expression is not a necessary mechanistic component of transplant destruction. In addition, these results implicate MHC class I-restricted CTLs but not MHC class II-restricted T cells in disease recurrence.
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Affiliation(s)
- Holly Y Young
- Department of Microbiology and Immunology, University of Western Ontario, London, ON, Canada
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Kuttler B, Steveling A, Klöting N, Morgenstern O, Wanka H. Aminoguanidine downregulates expression of cytokine-induced Fas and inducible nitric oxide synthase but not cytokine-enhanced surface antigens of rat islet cells. Biochem Pharmacol 2003; 66:2437-48. [PMID: 14637201 DOI: 10.1016/j.bcp.2003.09.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Autoimmune beta-cell destruction occurs directly by cell-mediated cytotoxicity or indirectly by cytokines released from infiltrating lymphocytes. Cytokines (IL-1beta/IFN-gamma) modify or induce expression of MHC antigens and ICAM-1 on beta-cells which can lead to an improved binding of T-lymphocytes to beta-cells and finally to an enhanced cell-mediated cytotoxicity. Cytokines also induce Fas-expression and inducible nitric oxide synthase (iNOS) causing generation of nitric oxide (NO) which is toxic for beta-cells. The iNOS inhibitor aminoguanidine (AG) delays diabetes onset, but does not reduce diabetes incidence. We wanted to know whether AG inhibits cytokine-induced expression of Fas, MHC antigens and ICAM-1 on beta-cells of LEW.1W and BB/OK rat islets after culture with IL-1beta/IFN-gamma. NO was completely inhibited by 5.0 mmol/L AG while 0.5 mmol/L had no inhibitory effect. AG downregulated Fas-expression on the surface of beta-cells. Cytokine-induced/enhanced expression of MHC class-II and ICAM-1 was not affected by any AG concentration. AG syngergistically increased cytokine-induced enhancement of MHC class-I antigen density. AG possibly blocks the indirect pathway of beta-cell damage in vivo due to inhibition of Fas and iNOS and improves direct cell-mediated cytotoxicity due to drastic increased MHC class-I expression. Inhibition of only one pathway of beta-cell destruction is not sufficient to prevent diabetes.
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Affiliation(s)
- Beate Kuttler
- Institute of Pathophysiology, Ernst-Moritz-Arndt-University, Greifswald, Greifswalder Str. 11c, D-17495 Karlsburg, Germany.
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Augstein P, Dunger A, Heinke P, Wachlin G, Berg S, Hehmke B, Salzsieder E. Prevention of autoimmune diabetes in NOD mice by troglitazone is associated with modulation of ICAM-1 expression on pancreatic islet cells and IFN-gamma expression in splenic T cells. Biochem Biophys Res Commun 2003; 304:378-84. [PMID: 12711326 DOI: 10.1016/s0006-291x(03)00590-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Thiazolidinediones acting as PPAR-gamma agonists are a new generation of oral antidiabetics addressing insulin resistance as a main feature of type-2 diabetes. In accordance to our results, pre-clinical studies have demonstrated that the thiazolinedione troglitazone prevents the development of insulin-dependent autoimmune type-1 diabetes. To investigate whether TGZ acts by affecting the ICAM-1/LFA-1 pathway and/or the Th1/Th2 cytokine balance in NOD mice, we analysed the IL-1beta-induced ICAM-1 expression on islet-cells and the LFA-1, CD25, IL-2, IFN-gamma, IL-4, and IL-10 expression on splenocytes. After 200 days of oral TGZ administration, islet cells from TGZ-treated NOD mice showed a reduced ICAM-1 expression in response to the pro-inflammatory cytokine IL-1beta. The expression of the ligand LFA-1 on CD4(+) and CD8(+) T-cells was comparable to that of placebo- and untreated controls. Also, the expression of Th1/Th2 cytokines was comparable in groups receiving TGZ or Placebo. Nevertheless, the investigated NOD mice segregated into IFN-gamma low- and IFN-gamma high producers as revealed by cluster analysis. Interestingly, the majority of TGZ-treated mice belonged to the cluster of IFN-gamma low producers. Thus, the prevention of autoimmune diabetes in NOD mice by TGZ seems to be associated with suppression of IL-1beta-induced ICAM-1 expression leading to a reduced vulnerability of pancreatic beta-cells during the effector stage of beta-cell destruction. In addition, IFN-gamma production was modulated, implicating that alteration of the Th1/Th2 cytokine balance might have contributed to diabetes prevention. The findings of this study suggest that TGZ exerts its effects by influencing both the beta-cells as the target of autoimmune beta-cell destruction and the T-cells as major effectors of the autoimmune process.
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Affiliation(s)
- Petra Augstein
- Institute of Diabetes "Gerhardt Katsch" Karlsburg e.V., Greifswalder Str.11e, 17495, Karlsburg, Germany.
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