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Moroni-González D, Sarmiento-Ortega VE, Diaz A, Brambila E, Treviño S. Pancreatic Antioxidative Defense and Heat Shock Proteins Prevent Islet of Langerhans Cell Death After Chronic Oral Exposure to Cadmium LOAEL Dose. Biol Trace Elem Res 2024; 202:3714-3730. [PMID: 37955768 DOI: 10.1007/s12011-023-03955-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2023] [Accepted: 11/06/2023] [Indexed: 11/14/2023]
Abstract
Cadmium, a hazardous environmental contaminant, is associated with metabolic disease development. The dose with the lowest observable adverse effect level (LOAEL) has not been studied, focusing on its effect on the pancreas. We aimed to evaluate the pancreatic redox balance and heat shock protein (HSP) expression in islets of Langerhans of male Wistar rats chronically exposed to Cd LOAEL doses, linked to their survival. Male Wistar rats were separated into control and cadmium groups (drinking water with 32.5 ppm CdCl2). At 2, 3, and 4 months, glucose, insulin, and cadmium were measured in serum; cadmium and insulin were quantified in isolated islets of Langerhans; and redox balance was analyzed in the pancreas. Immunoreactivity analysis of p-HSF1, HSP70, HSP90, caspase 3 and 9, and cell survival was performed. The results showed that cadmium exposure causes a serum increase and accumulation of the metal in the pancreas and islets of Langerhans, hyperglycemia, and hyperinsulinemia, associated with high insulin production. Cd-exposed groups presented high levels of reactive oxygen species and lipid peroxidation. An augment in MT and GSH concentrations with the increased enzymatic activity of the glutathione system, catalase, and superoxide dismutase maintained a favorable redox environment. Additionally, islets of Langerhans showed a high immunoreactivity of HSPs and minimal immunoreactivity to caspase associated with a high survival rate of Langerhans islet cells. In conclusion, antioxidative and HSP pancreatic defense avoids cell death associated with Cd accumulation in chronic conditions; however, this could provoke oversynthesis and insulin release, which is a sign of insulin resistance.
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Affiliation(s)
- Diana Moroni-González
- Laboratory of Chemical-Clinical Investigations, Department of Clinical Chemistry, Chemistry Department, Meritorious Autonomous University of Puebla, 14 Sur. FCQ1, Ciudad Universitaria, 72560, Puebla, C.P, Mexico
| | - Victor Enrique Sarmiento-Ortega
- Laboratory of Chemical-Clinical Investigations, Department of Clinical Chemistry, Chemistry Department, Meritorious Autonomous University of Puebla, 14 Sur. FCQ1, Ciudad Universitaria, 72560, Puebla, C.P, Mexico
| | - Alfonso Diaz
- Department of Pharmacy, Faculty of Chemistry Science, Meritorious Autonomous University of Puebla, 22 South, FCQ9, Ciudad Universitaria, 72560, Puebla, C.P, Mexico
| | - Eduardo Brambila
- Laboratory of Chemical-Clinical Investigations, Department of Clinical Chemistry, Chemistry Department, Meritorious Autonomous University of Puebla, 14 Sur. FCQ1, Ciudad Universitaria, 72560, Puebla, C.P, Mexico
| | - Samuel Treviño
- Laboratory of Chemical-Clinical Investigations, Department of Clinical Chemistry, Chemistry Department, Meritorious Autonomous University of Puebla, 14 Sur. FCQ1, Ciudad Universitaria, 72560, Puebla, C.P, Mexico.
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Pomeranz L, Li R, Yu X, Kelly L, Hassanzadeh G, Molina H, Gross D, Brier M, Vaisey G, Wang P, Jimenez-Gonzalez M, Garcia-Ocana A, Dordick J, Friedman J, Stanley S. Magnetogenetic cell activation using endogenous ferritin. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.06.20.545120. [PMID: 37786709 PMCID: PMC10541561 DOI: 10.1101/2023.06.20.545120] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
The ability to precisely control the activity of defined cell populations enables studies of their physiological roles and may provide therapeutic applications. While prior studies have shown that magnetic activation of ferritin-tagged ion channels allows cell-specific modulation of cellular activity, the large size of the constructs made the use of adeno-associated virus, AAV, the vector of choice for gene therapy, impractical. In addition, simple means for generating magnetic fields of sufficient strength have been lacking. Toward these ends, we first generated a novel anti-ferritin nanobody that when fused to transient receptor potential cation channel subfamily V member 1, TRPV1, enables direct binding of the channel to endogenous ferritin in mouse and human cells. This smaller construct can be delivered in a single AAV and we validated that it robustly enables magnetically induced cell activation in vitro . In parallel, we developed a simple benchtop electromagnet capable of gating the nanobody-tagged channel in vivo . Finally, we showed that delivering these new constructs by AAV to pancreatic beta cells in combination with the benchtop magnetic field delivery stimulates glucose-stimulated insulin release to improve glucose tolerance in mice in vivo . Together, the novel anti-ferritin nanobody, nanobody-TRPV1 construct and new hardware advance the utility of magnetogenetics in animals and potentially humans.
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Teratani T, Kasahara N, Fujimoto Y, Sakuma Y, Miki A, Goto M, Sata N, Kitayama J. Mesenchymal Stem Cells Secretions Enhanced ATP Generation on Isolated Islets during Transplantation. Islets 2022; 14:69-81. [PMID: 35034568 PMCID: PMC8765074 DOI: 10.1080/19382014.2021.2022423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The success of islet transplantation in both basic research and clinical settings has proven that cell therapy has the potential to cure diabetes. Islets intended for transplantation are inevitably subjected to damage from a number of sources, including ischemic injury during removal and delivery of the donor pancreas, enzymatic digestion during islet isolation, and reperfusion injury after transplantation in the recipient. Here, we found that protein factors secreted by porcine adipose-tissue mesenchymal stem cells (AT-MSCs) were capable of activating preserved porcine islets. A conditioned medium was prepared from the supernatant obtained by culturing porcine AT-MSCs for 2 days in serum-free medium. Islets were preserved at 4°C in University of Wisconsin solution during transportation and then incubated at 37°C in RPMI-1620 medium with fractions of various molecular weights prepared from the conditioned medium. After treatment with certain fractions of the AT-MSC secretions, the intracellular ATP levels of the activated islets had increased to over 160% of their initial values after 4 days of incubation. Our novel system may be able to restore the condition of isolated islets after transportation or preservation and may help to improve the long-term outcome of islet transplantation.Abbreviations: AT-MSC, adipose-tissue mesenchymal stem cell; Cas-3, caspase-3; DAPI, 4,6-diamidino-2-phenylindole; DTZ, dithizone; ES cell, embryonic stem cell; FITC, fluorescein isothiocyanate; IEQ, islet equivalent; INS, insulin; iPS cell, induced pluripotent stem cell; Luc-Tg rat, luciferase-transgenic rat; PCNA, proliferating cell nuclear antigen; PDX1, pancreatic and duodenal homeobox protein-1; UW, University of Wisconsin; ZO1, zona occludens 1.
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Affiliation(s)
- Takumi Teratani
- Division of Translational Research, Jichi Medical University, Tochigi, Japan
- Department of Surgery, Jichi Medical University, Tochigi, Japan
- CONTACT Takumi Teratani Division of Clinical Investigation, Jichi Medical University, 3311-1, Yakushiji, Shimotsukeshi, Tochigi329-0498, Japan
| | - Naoya Kasahara
- Department of Surgery, Jichi Medical University, Tochigi, Japan
| | | | - Yasunaru Sakuma
- Department of Surgery, Jichi Medical University, Tochigi, Japan
| | - Atsushi Miki
- Department of Surgery, Jichi Medical University, Tochigi, Japan
| | - Masafumi Goto
- New Industry Creation Hatchery Center, Tohoku University, Miyagi, Japan
| | - Naohiro Sata
- Department of Surgery, Jichi Medical University, Tochigi, Japan
| | - Joji Kitayama
- Division of Translational Research, Jichi Medical University, Tochigi, Japan
- Department of Surgery, Jichi Medical University, Tochigi, Japan
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Zhang L, Turan A, Shirwan H, Yolcu ES. A modified surgical procedure using minimally invasive ileocolic vein perfusion in a mouse intrahepatic islet transplant model. STAR Protoc 2022; 3:101416. [PMID: 35620067 PMCID: PMC9127695 DOI: 10.1016/j.xpro.2022.101416] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Murine intrahepatic islet transplantation is a clinically relevant but technically challenging surgical procedure because of frequent lethal postoperative bleeding. Here, we describe a protocol for mouse pancreatic islet isolation, purification, and culture. Besides, we also describe a protocol for intrahepatic islet transplantation through the ileocolic vein. Intrahepatic islet transplantation through the ileocolic vein, as opposed to traditional islet perfusion via the main portal vein, has the advantage of improving recovery after surgery and may facilitate islet survival and function in preclinical settings. For complete details on the use and execution of this protocol, please refer to Shrestha et al. (2020).
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Affiliation(s)
- Lei Zhang
- Department of Child Health, University of Missouri, Columbia, MO 65211, USA
| | - Ali Turan
- Department of Molecular Microbiology and Immunology, University of Missouri, Columbia, MO 65211, USA
| | - Haval Shirwan
- Department of Child Health, University of Missouri, Columbia, MO 65211, USA
- Department of Molecular Microbiology and Immunology, University of Missouri, Columbia, MO 65211, USA
| | - Esma S. Yolcu
- Department of Child Health, University of Missouri, Columbia, MO 65211, USA
- Department of Molecular Microbiology and Immunology, University of Missouri, Columbia, MO 65211, USA
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Wang J, Wang D, Chen X, Yuan S, Bai L, Liu C, Zeng YA. Isolation of mouse pancreatic islet Procr + progenitors and long-term expansion of islet organoids in vitro. Nat Protoc 2022; 17:1359-1384. [PMID: 35396545 DOI: 10.1038/s41596-022-00683-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 12/22/2021] [Indexed: 12/22/2022]
Abstract
Insulin production is required for glucose homeostasis. Pancreatic islet β cells are the only cells that produce insulin in humans; however, generation of functional β cells in vitro from embryonic or adult tissues has been challenging. Here, we describe isolation of pancreatic islet progenitors from adult mice, which enables the efficient generation and long-term expansion of functional islet organoids in vitro. This protocol starts with purification of protein C receptor (Procr)-expressing islet progenitors. Coculture with endothelial cells generates islet organoids in vitro that can be expanded by passage. Functional maturation is achieved as a consequence of a prolonged culture period and cyclic glucose stimulation. Primary islet organoids form in 7-10 days. Subsequently, each passage takes 1 week, with the final maturation step requiring 3 weeks of additional culture. The resulting organoids are predominantly composed of β cells but also contain small proportions of α, δ and pancreatic polypeptide cells. The organoids sense glucose and secrete insulin. This approach thus provides a strategy for β cell generation in vitro and an organoid system to study islet regeneration and diseases.
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Affiliation(s)
- Jingqiang Wang
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Daisong Wang
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
- Hubrecht Institute and Oncode Institute, Royal Netherlands Academy of Arts and Sciences (KNAW) and University Medical Centre Utrecht, Netherlands, Utrecht University and Princess Maxima Center, Utrecht, Netherlands
| | - Xinyi Chen
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Shubo Yuan
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Lanyue Bai
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Chunye Liu
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Yi Arial Zeng
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China.
- School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Hangzhou, China.
- Bio-Research Innovation Center, Institute of Biochemistry and Cell Biology, Suzhou, China.
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A Practical Guide to Rodent Islet Isolation and Assessment Revisited. Biol Proced Online 2021; 23:7. [PMID: 33641671 PMCID: PMC7919091 DOI: 10.1186/s12575-021-00143-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 01/26/2021] [Indexed: 02/06/2023] Open
Abstract
Insufficient insulin secretion is a key component of both type 1 and type 2 diabetes. Since insulin is released by the islets of Langerhans, obtaining viable and functional islets is critical for research and transplantation. The effective and efficient isolation of these small islands of endocrine cells from the sea of exocrine tissue that is the rest of the pancreas is not necessarily simple or quick. Choosing and administering the digestive enzyme, separation of the islets from acinar tissue, and culture of islets are all things that must be considered. The purpose of this review is to provide a history of the development of islet isolation procedures and to serve as a practical guide to rodent islet research for newcomers to islet biology. We discuss key elements of mouse islet isolation including choosing collagenase, the digestion process, purification of islets using a density gradient, and islet culture conditions. In addition, this paper reviews techniques for assessing islet viability and function such as visual assessment, glucose-stimulated insulin secretion and intracellular calcium measurements. A detailed protocol is provided that describes a common method our laboratory uses to obtain viable and functional mouse islets for in vitro study. This review thus provides a strong foundation for successful procurement and purification of high-quality mouse islets for research purposes.
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Preparing Highly Viable Single-Cell Suspensions from Mouse Pancreatic Islets for Single-Cell RNA Sequencing. STAR Protoc 2020; 1:100144. [PMID: 33377038 PMCID: PMC7757316 DOI: 10.1016/j.xpro.2020.100144] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Pancreatic islets consist of several cell types, including alpha, beta, delta, epsilon, and PP cells. Due to cellular heterogeneity, it is challenging to interpret whole-islet transcriptome data. Single-cell transcriptomics offers a powerful method for investigating gene expression at the single-cell level and identifying cellular heterogeneity and subpopulations. Here, we describe a protocol for mouse pancreatic islet isolation, culturing, and dissociation into a single-cell suspension. This protocol yields highly viable cells for successful library preparation and single-cell RNA sequencing. For complete details on the use and execution of this protocol, please refer to Lee et al. (2020). A detailed protocol for the isolation and culture of pancreatic islets from mice A procedure for dissociation of mouse islets into a single-cell suspension Method consistently yields optimal cell viability (90%) for scRNA sequencing
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Injury factors alter miRNAs profiles of exosomes derived from islets and circulation. Aging (Albany NY) 2019; 10:3986-3999. [PMID: 30552311 PMCID: PMC6326691 DOI: 10.18632/aging.101689] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 11/26/2018] [Indexed: 12/31/2022]
Abstract
Islets damage is a major abnormality underling diabetes. Recent studies suggested the value of exosomes in diagnosis. This study aimed to investigate the impact of injury factors on the miRNA profiles of islet exosomes and determine whether circulating exosomal miRNAs is suitable as biomarkers of islets damage. Islets were isolated from ICR mice and induced injury in vitro by mixed cytokines (Tumor Necrosis Factor-α, Interleukin -1β and Interferon-γ) or streptozotocin (STZ), and exosomes were derived from the cultural supernatant. Using miRNA microarray analysis, we found 22 and 11 differentially expressed miRNAs in islet exosomes of STZ and cytokines treatment, respectively, including 6 miRNAs as the intersection of two injured conditions. Thereinto, mmu-miR-375-3p and mmu-miR-129-5p could be validated by qRT-PCR. Then, Serum exosomes were isolated from STZ injected mice and subjects with various glucose metabolism states and diabetic duration. qRT-PCR demonstrated exosomal mmu-miR-375-3p dramatically increased in serum of STZ treated mouse prior to the disturbance of blood glucose and insulin. In human serum exosomes, hsa-miR-375-3p was elevated in new-onset diabetes patients. Overall, our results suggest that injury factors changed miRNA profiles of exosomes derived from islets and exosomal miR-375-3p showed promising potential as a biomarker of islets damage.
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Wang Z, Rui X, Qiu J, Yan Y, Gan J, Liu S, Wang L, Zhang J, Wang C, Dong L. Growing Trans-Species Islets in Tumor Extract-Remodeled Testicles. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2019; 6:1801694. [PMID: 30937263 PMCID: PMC6425427 DOI: 10.1002/advs.201801694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 12/12/2018] [Indexed: 06/09/2023]
Abstract
Although pancreatic islet transplantation holds promise for the treatment of type I diabetes, its application has been significantly hampered by transplant rejection. Here, an approach is demonstrated to support trans-species islet beta cells from a rat to grow and function in the body of a mouse host while overcoming graft rejection. This approach, which builds on remodeling of the mouse testicle by local injection of a tumor homogenate, establishes an immunosuppressive and proregenerative niche in the testicle. This remodeling proves necessary and effective in shaping the testicle into a unique site to accommodate xenograft cells. Rat pancreatic beta cells-from both the insulinoma (cancer cells) and pancreatic islet (normal tissue)-survive, grow, and form a desirable morphology in the remodeled mouse testicle. Notably, when hyperglycemia is induced in the host body, these xenografts secrete insulin to regulate the blood glucose level in mice for as long as 72 days. Furthermore, no graft rejection, acute inflammation, or safety risks are observed throughout the study. In summary, it is demonstrated that the growth of xenogeneic insulinoma cells in a mouse testicle might serve as an alternative approach for islet transplantation.
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Affiliation(s)
- Zhenzhen Wang
- Nanjing Drum Tower Hospitalthe Affiliated Hospital of Nanjing University Medical SchoolNanjingJiangsu210093China
- State Key Laboratory of Pharmaceutical BiotechnologySchool of Life SciencesNanjing UniversityNanjingJiangsu210023China
- State Key Laboratory of Quality Research in Chinese MedicineInstitute of Chinese Medical SciencesUniversity of MacauTaipa999078MacauSAR
| | - Xiaying Rui
- State Key Laboratory of Pharmaceutical BiotechnologySchool of Life SciencesNanjing UniversityNanjingJiangsu210023China
| | - Junni Qiu
- State Key Laboratory of Pharmaceutical BiotechnologySchool of Life SciencesNanjing UniversityNanjingJiangsu210023China
| | - Yiqing Yan
- State Key Laboratory of Pharmaceutical BiotechnologySchool of Life SciencesNanjing UniversityNanjingJiangsu210023China
| | - Jingjing Gan
- State Key Laboratory of Pharmaceutical BiotechnologySchool of Life SciencesNanjing UniversityNanjingJiangsu210023China
| | - Shang Liu
- State Key Laboratory of Pharmaceutical BiotechnologySchool of Life SciencesNanjing UniversityNanjingJiangsu210023China
| | - Lintao Wang
- State Key Laboratory of Pharmaceutical BiotechnologySchool of Life SciencesNanjing UniversityNanjingJiangsu210023China
- State Key Laboratory of Quality Research in Chinese MedicineInstitute of Chinese Medical SciencesUniversity of MacauTaipa999078MacauSAR
| | - Junfeng Zhang
- Nanjing Drum Tower Hospitalthe Affiliated Hospital of Nanjing University Medical SchoolNanjingJiangsu210093China
- State Key Laboratory of Pharmaceutical BiotechnologySchool of Life SciencesNanjing UniversityNanjingJiangsu210023China
| | - Chunming Wang
- State Key Laboratory of Quality Research in Chinese MedicineInstitute of Chinese Medical SciencesUniversity of MacauTaipa999078MacauSAR
| | - Lei Dong
- State Key Laboratory of Pharmaceutical BiotechnologySchool of Life SciencesNanjing UniversityNanjingJiangsu210023China
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Saliba Y, Farès N. Isolation, Purification, and Culture of Mouse Pancreatic Islets of Langerhans. Methods Mol Biol 2019; 1940:255-265. [PMID: 30788831 DOI: 10.1007/978-1-4939-9086-3_18] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Pancreatic islets constitute an important tool for research and clinical applications in the field of diabetes. They are used for transplantation, unraveling new mechanisms in insulin secretion, studying pathophysiological pathways in diseased cells, and pharmacological research aimed at developing improved therapeutic strategies. Therefore, fine-tuning islet isolation protocols remains an important objective for reliable investigations. Here we describe a relatively simple mouse islet isolation protocol that relies on enzymatic digestion using low-activity collagenase and several sedimentation and Percoll gradient steps.
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Affiliation(s)
- Youakim Saliba
- Laboratoire de Recherche en Physiologie et Physiopathologie LRPP, Pôle Technologie Santé, Faculté de Médecine, Université Saint Joseph, Beirut, Lebanon
| | - Nassim Farès
- Laboratoire de Recherche en Physiologie et Physiopathologie LRPP, Pôle Technologie Santé, Faculté de Médecine, Université Saint Joseph, Beirut, Lebanon.
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Montoya-Ruiz C, Rodas JD. Epidemiological Surveillance of Viral Hemorrhagic Fevers With Emphasis on Clinical Virology. Methods Mol Biol 2018; 1604:55-78. [PMID: 28986825 DOI: 10.1007/978-1-4939-6981-4_4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
Abstract
This article will outline surveillance approaches for viral hemorrhagic fevers. Specific methods for surveillance of clinical samples will be emphasized. Separate articles will describe methods for surveillance of rodent-borne viruses (roboviruses) and arthropod-borne viruses (arboviruses). Since the appearance of hantaviruses and arenaviruses in the Americas, more than 30 different species in each group have been established, and therefore they have become the most frequently emerging viruses. Flaviviruses such as yellow fever and dengue viruses, although easier to recognize, are also more widely spread and therefore considered a very important public health issue, particularly for under-developed countries. On the other hand, marburgviruses and ebolaviruses, previously thought to be restricted to the African continent, have recently been shown to be more global. For many of these agents virus isolation has been a challenging task: trapping the specific vectors (mosquitoes and ticks), and reservoirs (rodents and bats), or obtaining the samples from suspected clinical human cases demands special protective gear, uncommon devices (respirators), special facilities (BSL-3 and 4), and particular skills to recognize the slow and inapparent cytopathic effects in cell culture. Alternatively, serological and molecular approaches have been very helpful in discovering and describing newly emerging viruses in many areas where the previous resources are unavailable. Unfortunately, in many cases, detailed studies have been performed only after outbreaks occur, and then active surveillance is needed to prevent viral dissemination in human populations.
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Affiliation(s)
- Carolina Montoya-Ruiz
- Linea de Zoonosis Emergentes y Re-emergentes, Grupo Centauro, Facultad de Ciencias Agrarias, Universidad de Antioquia, Calle 70 No. 52-21, Medellín, Colombia
| | - Juan David Rodas
- Linea de Zoonosis Emergentes y Re-emergentes, Grupo Centauro, Facultad de Ciencias Agrarias, Universidad de Antioquia, Calle 70 No. 52-21, Medellín, Colombia.
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Shiota C, Prasadan K, Guo P, Fusco J, Xiao X, Gittes GK. Gcg CreERT2 knockin mice as a tool for genetic manipulation in pancreatic alpha cells. Diabetologia 2017; 60:2399-2408. [PMID: 28884202 PMCID: PMC5671347 DOI: 10.1007/s00125-017-4425-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 07/19/2017] [Indexed: 01/05/2023]
Abstract
AIMS/HYPOTHESIS The Cre/loxP system, which enables tissue-specific manipulation of genes, is widely used in mice for diabetes research. Our aim was to develop a new Cre-driver mouse line for the specific and efficient manipulation of genes in pancreatic alpha cells. METHODS A Gcg CreERT2 knockin mouse, which expresses a tamoxifen-inducible form of Cre from the endogenous preproglucagon (Gcg) gene locus, was generated by homologous recombination. The new Gcg CreERT2 mouse line was crossed to the Rosa26 tdTomato (R26 tdTomato ) Cre reporter mouse line in order to evaluate the tissue specificity, efficiency and tamoxifen dependency of Gcg CreERT2 -mediated recombination. Cell types of pancreatic islets were identified using immunohistochemistry. Biochemical and physiological data, including blood glucose levels, plasma glucagon and glucagon-like peptide (GLP)-1 levels, and pancreatic glucagon content, were collected and used to assess the overall effect of Gcg gene targeting on Gcg CreERT2/w heterozygous mice. RESULTS Tamoxifen-treated Gcg CreERT2/w ;R26 tdTomato/w mice displayed Cre reporter activity, i.e. expression of tdTomato red fluorescent protein (RFP) in all known cells that produce proglucagon-derived peptides. In the adult pancreas, RFP was detected in 94-97% of alpha cells, whereas it was detected in a negligible (~ 0.2%) proportion of beta cells. While more than 98% of cells labelled with tamoxifen-induced RFP were glucagon-positive cells, 14-25% of pancreatic polypeptide (PP)-positive cells were also positive for RFP, indicating the presence of glucagon/PP bihormonal cell population. Tamoxifen-independent expression of RFP occurred in approximately 6% of alpha cells. In contrast to alpha cells and GLP-1-producing neurons, in which RFP expression persisted for at least 5 months after tamoxifen administration (presumably due to rare neogenesis in these cell types in adulthood), nearly half of RFP-positive intestinal L cells were replaced with RFP-negative L cells over the first 2 weeks after tamoxifen administration. Heterozygous Gcg CreERT2/w mice showed reduced Gcg mRNA levels in islets, but maintained normal levels of pancreatic and plasma glucagon. The mice did not exhibit any detectable baseline physiological abnormalities, at least in young adulthood. CONCLUSIONS/INTERPRETATION The newly developed Gcg CreERT2 knockin mouse shows faithful expression of CreERT2 in pancreatic alpha cells, intestinal L cells and GLP-1-producing neurons. This mouse line will be particularly useful for manipulating genes in alpha cells, due to highly specific and efficient CreERT2-mediated recombination in this cell type in the pancreas.
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Affiliation(s)
- Chiyo Shiota
- Division of Pediatric Surgery, Department of Surgery, Children's Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, 4401 Penn Ave, Pittsburgh, PA, 15224, USA.
- Department of Molecular Physiology and Biophysics, Vanderbilt University, 2215 Garland Ave, Nashville, TN, 37232, USA.
| | - Krishna Prasadan
- Division of Pediatric Surgery, Department of Surgery, Children's Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, 4401 Penn Ave, Pittsburgh, PA, 15224, USA
| | - Ping Guo
- Division of Pediatric Surgery, Department of Surgery, Children's Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, 4401 Penn Ave, Pittsburgh, PA, 15224, USA
| | - Joseph Fusco
- Division of Pediatric Surgery, Department of Surgery, Children's Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, 4401 Penn Ave, Pittsburgh, PA, 15224, USA
| | - Xiangwei Xiao
- Division of Pediatric Surgery, Department of Surgery, Children's Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, 4401 Penn Ave, Pittsburgh, PA, 15224, USA
| | - George K Gittes
- Division of Pediatric Surgery, Department of Surgery, Children's Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, 4401 Penn Ave, Pittsburgh, PA, 15224, USA.
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Ayenehdeh JM, Niknam B, Hashemi SM, Rahavi H, Rezaei N, Soleimani M, Tajik N. Introducing a New Experimental Islet Transplantation Model using Biomimetic Hydrogel and a Simple High Yield Islet Isolation Technique. IRANIAN BIOMEDICAL JOURNAL 2017; 21:218-27. [PMID: 27752182 PMCID: PMC5459937 DOI: 10.18869/acadpub.ibj.21.4.218] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Revised: 02/15/2016] [Accepted: 02/20/2016] [Indexed: 01/26/2023]
Abstract
BACKGROUND Islet transplantation could be an ideal alternative treatment to insulin therapy for type 1 diabetes Mellitus (T1DM). This clinical and experimental field requires a model that covers problems such as requiring a large number of functional and viable islets, the optimal transplantation site, and the prevention of islet dispersion. Hence, the methods of choice for isolation of functional islets and transplantation are crucial. METHODS The present study has introduced an experimental model that overcomes some critical issues in islet transplantation, including in situ pancreas perfusion by digestive enzymes through common bile duct. In comparison with conventional methods, we inflated the pancreas in Petri dishes with only 1 ml collagenase type XI solution, which was followed by hand-picking isolation or Ficoll gradient separation to purify the islets. Then we used a hydrogel composite in which the islets were embedded and transplanted into the peritoneal cavity of the streptozotocin-induced diabetic C57BL/6 mice. RESULTS As compared to the yield of the classical methods, in our modified technique, the mean yield of isolation was about 130-200 viable islets/mouse pancreas. In vitro glucose-mediated insulin secretion assay indicated an appropriate response in isolated islets. In addition, data from in vivo experiments revealed that the allograft remarkably maintained blood glucose levels under 400 mg/dl and hydrogel composite prevents the passage of immune cells. CONCLUSION In the model presented here, the rapid islet isolation technique and the application of biomimetic hydrogel wrapping of islets could facilitate islet transplantation procedures.
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Affiliation(s)
- Jamal Mohammadi Ayenehdeh
- Department of Immunology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
- Immunology Research Center (IRC), Iran University of Medical Sciences, Tehran, Iran
| | - Bahareh Niknam
- Immunology Research Center (IRC), Iran University of Medical Sciences, Tehran, Iran
- Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Seyed Mahmoud Hashemi
- Department of Immunology, School of Medicine, Tehran, Shahid Beheshti University of Medical Sciences, Iran
| | - Hossein Rahavi
- Immunology Research Center (IRC), Iran University of Medical Sciences, Tehran, Iran
| | - Nima Rezaei
- Department of Immunology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
- Research Center for Immunodeficiencies, Tehran University of Medical Sciences, Children’s Medical Center, Tehran, Iran
- Universal Scientific Education and Research Network (USERN), Tehran, Iran
| | - Masoud Soleimani
- Department of Stem Cell Biology, Stem Cell Technology Research Center, Tehran, Iran
| | - Nader Tajik
- Immunology Research Center (IRC), Iran University of Medical Sciences, Tehran, Iran
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Xu J, Peng B, Zhang C, Xu J, Ma Y, Lu X. A modified method for isolating mouse islets of an adequate quality, quantity, and purity. Biochem Cell Biol 2017; 95:455-458. [PMID: 28257581 DOI: 10.1139/bcb-2016-0204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Mouse islets are widely used in diabetes research. Thus an adequate quality, quantity, and purity of islets are needed for high-quality investigations. We performed a combination of filtration and density gradient separation and optimized many steps in the islet isolation procedure, including perfusion, digestion, and purification. Our results show that an increased quality, quantity, and purity of isolated islets can be achieved using these modifications. Moreover, this method can guarantee maximal recovery and purity of the isolated islets and is easy to perform with practice.
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Affiliation(s)
- Jiejie Xu
- a Department of Hepatic Surgery, the First Affiliated Hospital, Sun Yat-Sen University, No. 58 Zhongshan 2nd Road, Guangzhou 510080, P.R. China
| | - Baogang Peng
- a Department of Hepatic Surgery, the First Affiliated Hospital, Sun Yat-Sen University, No. 58 Zhongshan 2nd Road, Guangzhou 510080, P.R. China
| | - Caiyun Zhang
- b Department of Hepatobiliary Surgery, Meizhou People's Hospital, No. 63 Huangtang Road, Meizhou 514000, P.R. China
| | - Jiwei Xu
- b Department of Hepatobiliary Surgery, Meizhou People's Hospital, No. 63 Huangtang Road, Meizhou 514000, P.R. China
| | - Yi Ma
- c Organ Transplant Center, the First Affiliated Hospital, Sun Yat-Sen University, No. 58 Zhongshan 2nd Road, Guangzhou 510080, P.R. China
| | - Xinjun Lu
- b Department of Hepatobiliary Surgery, Meizhou People's Hospital, No. 63 Huangtang Road, Meizhou 514000, P.R. China
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15
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An optimized protocol for purification of functional islets of Langerhans. J Transl Med 2017; 97:70-83. [PMID: 27892930 DOI: 10.1038/labinvest.2016.123] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Accepted: 10/21/2016] [Indexed: 12/31/2022] Open
Abstract
Islets of Langerhans and β-cell isolation constitute routinely used cell models for diabetic research, and refining islet isolation protocols and cell quality assessment is a high priority. Numerous protocols have been published describing isolate of islets, but often rigorous and systematic assessment of their integrity is lacking. Herein, we propose a new protocol for optimal generation of islets. Pancreases from mice and rats were excised and digested using a low-activity collagenase solution and islets were then purified by a series of sedimentations and a Percoll gradient. Islets were maintained in culture for 5 days, during which viability, pro/antiapoptotic, and islet-specific genes, glucose-stimulated calcium entry, glucose uptake, and insulin secretion were assessed. The commonly used islet isolation technique by collagenase injection through the common bile duct (CBD) was also performed and compared with the present approach. This new protocol produced islets that retained a healthy status as demonstrated by the yield of stable living cells. Furthermore, calcium oscillation, glucose uptake, and insulin secretion remained intact in the islet cultures. This was reproducible when many rodent species were used, and neither sex nor age affected the cells behavior. When compared with the CBD technique, islet physiology was similar. Finally, this approach was used to uncover new ion channel candidates implicated in insulin secretion. In conclusion, this study outlines an efficient protocol for islet preparation that may support research into new therapeutic targets in diabetes research.
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Ramírez-Domínguez M. Isolation of Mouse Pancreatic Islets of Langerhans. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 938:25-34. [DOI: 10.1007/978-3-319-39824-2_3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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17
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Improved Islet Purity by the Hypertonic-Hypotonic Method. Int J Artif Organs 2014; 37:477-85. [DOI: 10.5301/ijao.5000335] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/29/2014] [Indexed: 12/30/2022]
Abstract
Introduction Islet purification is usually performed using the density gradient separation method, but the purity of islets is low because exocrine cells and the embedded islets are hard to remove by using only the density gradient method. The aim of this study was to establish a new islet purification process comprising a hypertonic-hypotonic treatment step followed by a density gradient centrifugation step to improve the purity of islets. Methods The Plackett-Burman method was used to determine which factors had a significant influence on the purity of islets obtained after the hypertonic-hypotonic treatment step. Results The hypertonic solution concentration and the incubation time were both found to have a significant effect on islet purity. The purity of islets obtained using the modified purification process was significantly higher than that of islets obtained by density gradient alone (97% vs. 87.23%). Importantly, good cell viability and normal insulin secretion ability of islets were maintained following the modified purification. Conclusions The new purification process allows isolation of islets with improved purity and does not compromise the viability or function of the islets.
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18
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Filtration is a time-efficient option to Histopaque, providing good-quality islets in mouse islet isolation. Cytotechnology 2014; 67:199-206. [PMID: 24443076 DOI: 10.1007/s10616-014-9690-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Accepted: 01/06/2014] [Indexed: 12/16/2022] Open
Abstract
Pancreatic islet transplantation is a promising therapy for Type I Diabetes. For many years the method used worldwide for islet purification in both rodent and human islet isolation has been Ficoll-based density gradients, such as Histopaque. However, it is difficult to purify islets in laboratories with staff limitations when large scale isolations are required. We hypothesized that filtration could be a more simple and fast alternative to obtain good quality islets. Four separate islet isolations were performed per method, comparing filtration and Histopaque purification with handpicking as the gold standard method for islet purity. Different parameters of quality were assessed: yield in number of islets per pancreas, purity by dithizone staining, viability by Fluorescein Diacetate/Propidium Iodide vital staining and in vitro functionality assessed by Glucose Stimulated Insulin Secretion. Time efficiency and cost were also analyzed. The overall quality of the islets obtained both by Histopaque and filtration was good. Filtration saved almost 90 % of the time consumed by Histopaque purification, and was also cheaper. However, one-third of the islets were lost. Since human and rodent islets share similar size but different density, filtration appears as a purification method with potential interest in translation to clinic.
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Raposo do Amaral AS, Pawlick RL, Rodrigues E, Costal F, Pepper A, Ferreira Galvão FH, Correa-Giannella ML, Shapiro AM. Glutathione ethyl ester supplementation during pancreatic islet isolation improves viability and transplant outcomes in a murine marginal islet mass model. PLoS One 2013; 8:e55288. [PMID: 23424628 PMCID: PMC3570543 DOI: 10.1371/journal.pone.0055288] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Accepted: 12/19/2012] [Indexed: 12/28/2022] Open
Abstract
Background The success of pancreatic islet transplantation still faces many challenges, mainly related to cell damage during islet isolation and early post-transplant. The increased generation of reactive oxygen species (ROS) during islet isolation and the consumption of antioxidant defenses appear to be an important pathway related to islet damage. Methodology/Principal Findings In the present study we evaluated whether supplementation of glutathione-ethyl-ester (GEE) during islet isolation could improve islet viability and transplant outcomes in a murine marginal islet mass model. We also cultured human islets for 24 hours in standard CMRL media with or without GEE supplementation. Supplementation of GEE decreased the content of ROS in isolated islets, leading to a decrease in apoptosis and maintenance of islet viability. A higher percentage of mice transplanted with a marginal mass of GEE treated islets became euglycemic after transplant. The supplementation of 20 mM GEE in cultured human islets significantly reduced the apoptosis rate in comparison to untreated islets. Conclusions/Significance GEE supplementation was able to decrease the apoptosis rate and intracellular content of ROS in isolated islets and might be considered a potential intervention to improve islet viability during the isolation process and maintenance in culture before islet transplantation.
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Affiliation(s)
- Alexandre S. Raposo do Amaral
- Alberta Diabetes Institute, University of Alberta, Edmonton AB, Canada
- Laboratório de Endocrinologia Celular e Molecular (LIM-25) do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Rena L. Pawlick
- Alberta Diabetes Institute, University of Alberta, Edmonton AB, Canada
| | - Erika Rodrigues
- Laboratório de Endocrinologia Celular e Molecular (LIM-25) do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Flavia Costal
- Laboratório de Endocrinologia Celular e Molecular (LIM-25) do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Andrew Pepper
- Alberta Diabetes Institute, University of Alberta, Edmonton AB, Canada
| | - Flávio H. Ferreira Galvão
- Unidade de Transplante e Cirurgia de Fígado (LIM37), Departamento de Gastroenterologia da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Maria Lucia Correa-Giannella
- Laboratório de Endocrinologia Celular e Molecular (LIM-25) do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - A. M.James Shapiro
- Alberta Diabetes Institute, University of Alberta, Edmonton AB, Canada
- * E-mail:
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20
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Increased yield and improved transplantation outcome of mouse islets with bovine serum albumin. J Transplant 2012; 2012:856386. [PMID: 23304445 PMCID: PMC3523609 DOI: 10.1155/2012/856386] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Accepted: 11/11/2012] [Indexed: 11/18/2022] Open
Abstract
Isolation and transplantation of rodent islets are frequently used as a tool for predicting the behavior of new protocols for islet allotransplants in type 1 diabetes patients. Bovine serum albumin (BSA) is recognized as a protease inhibitor possibly protecting function and viability in islets. For this study, the addition of 0.2% BSA to the isolation protocol resulted in a 30% increase in islet yields while other parameters, such as viability and function, retained high islet quality. In vivo, a minimal mass of 70 BSA treated islets showed their ability to control glycemia levels in diabetic mice by bringing the average blood glucose to 153 ± 13.2 mg/dL compared to 288 ± 22.6 mg/dL without BSA. Our results show that the simple addition of BSA to the isolation protocol constitutes a reliable and reproducible method for increasing islet yield. Also adding BSA to the transplantation medium improves islet function in vivo. The method outlined here can reduce the overall number of animals needed per experiment and also reduce the time and resources needed for islet preparation.
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21
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Stull ND, Breite A, McCarthy R, Tersey SA, Mirmira RG. Mouse islet of Langerhans isolation using a combination of purified collagenase and neutral protease. J Vis Exp 2012:4137. [PMID: 22987198 PMCID: PMC3490250 DOI: 10.3791/4137] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The interrogation of beta cell gene expression and function in vitro has squarely shifted over the years from the study of rodent tumorigenic cell lines to the study of isolated rodent islets. Primary islets offer the distinct advantage that they more faithfully reflect the biology of intracellular signaling pathways and secretory responses. Whereas the method of islet isolation using tissue dissociating enzyme (TDE) preparations has been well established in many laboratories1-4, variations in the consistency of islet yield and quality from any given rodent strain limit the extent and feasibility of primary islet studies. These variations often occur as a result of the crude partially purified TDEs used in the islet isolation procedure; TDEs frequently exhibit lot-to-lot variations in activity and often require adjustments to the dose of enzyme used. A small number of reports have used purified TDEs for rodent cell isolations5, 6, but the practice is not widespread despite the routine use and advantages of purified TDEs for human islet isolations. In collaboration with VitaCyte, LLC (Indianapolis, IN), we developed a modified mouse islet isolation protocol based on that described by Gotoh7, 8, in which the TDEs are perfused directly into the pancreatic duct of mice, followed by crude tissue fractionation through a Histopaque gradient9, and isolation of purified islets. A significant difference in our protocol is the use of purified collagenase (CIzyme MA) and neutral protease (CIzyme BP) combination. The collagenase was characterized by the use of a6 fluorescence collagen degrading activity (CDA) assay that utilized fluorescently labeled soluble calf skin fibrils as substrate6. This substrate is more predictive of the kinetics of collagen degradation in the tissue matrix because it relies on native collagen as the substrate. The protease was characterized with a sensitive fluorescent kinetic assay10. Utilizing these improved assays along with more traditional biochemical analysis enable the TDE to be manufactured more consistently, leading to improved performance consistency between lots. The protocol described in here was optimized for maximal islet yield and optimal islet morphology using C57BL/6 mice. During the development of this protocol, several combinations of collagenase and neutral proteases were evaluated at different concentrations, and the final ratio of collagenase:neutral protease of 35:10 represents enzyme performance comparable to Sigma Type XI. Because significant variability in average islet yields from different strains of rats and mice have been reported, additional modifications of the TDE composition should be made to improve the yield and quality of islets recovered from different species and strains.
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Affiliation(s)
- Natalie D Stull
- Department of Pediatrics and the Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indiana, USA
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Advances and challenges in islet transplantation: islet procurement rates and lessons learned from suboptimal islet transplantation. J Transplant 2011; 2011:979527. [PMID: 22235361 PMCID: PMC3253477 DOI: 10.1155/2011/979527] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2011] [Accepted: 10/04/2011] [Indexed: 01/22/2023] Open
Abstract
The initial step in successful islet transplantation is procurement of healthy donor islets. Given the limited number of donor pancreata selected for islet isolation and that islets from multiple donors are typically required to obtain insulin independence, it is critical to improve pancreas procurement rates and yield of islets for transplantation. Islets are delicate microorgans that are susceptible to apoptosis, hypoxia, and ischemia during isolation, culture, and the peritransplant period. Once the islets are engrafted, both prompt revascularization and protection from beta-cell death and graft rejection are key to secure long-term survival and function. To facilitate the engraftment of more robust islets suitable for combating the challenging isolation period and proinflammatory transplantation milieu, numerous approaches have been employed to prevent beta-cell dysfunction and death including immune modulation, prevention of apoptosis and hypoxia, as well as stimulation of growth factors, angiogenesis, and reinnervation. In addition to briefly discussing islet isolation procedures, procurement rates, and islet transplantation, the relevant literature pertaining to successful suboptimal islet transplantation is reviewed to provide insight into potential approaches to balance the limited supply of available donor islets.
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