Improved recovery of human islets from young donor pancreases utilizing increased protease dose to collagenase for digesting peri‐islet extracellular matrix

Daniel Brandhorst,1,2 Limor Baruch,3 Heide Brandhorst,1,2 Stasia Krishtul,3 Marcelle Machluf,3 Paul R.V. Johnson1,2 1Research Group for Islet Transplantation, Nuffield Department of Surgical Sciences, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom 2Oxford Consortium for Islet Transplantation, Oxford Centre for Diabetes, Endocrinology, and Metabolism (OCDEM), Churchill Hospital, University of Oxford, Oxford, United Kingdom 3Laboratory for Cancer Drug Delivery and Cell Based Technologies, Faculty of Biotechnology and Food Engineering, Technion, Israel Institute of Technology, Haifa, Israel Aim Islet isolation essentially requires dissociation of islet basement membranes by collagenolytic enzymes. This is associated with reduced islet function and increased cell death. Previous ex-vivo and in-vivo studies demonstrated that individual extracellular matrix proteins (ECMPs) can increase islet survival. As the natural ECM is a tissue-defined complex network we propose a novel concept for creating a specific islet matrix by using the whole pancreatic ECM (WPM). In contrast to previous studies, ECMPs were dissolved in media rather than coating of culture vessel surfaces. Methods Islets, isolated from pancreases of 6 human DBD donors (52±3 years, 28.5±1.5 BMI, 6.4±0.7 hours CIT), were cultured for 4–5 days in hypoxic atmosphere (2% oxygen). Islets were suspended in CMRL 1066 supplemented with 2% FCS and WPM-gel (200 µg/mL) extracted and purified from porcine pancreases. The WPM-gel was compared with a pre-tested combination of human ECMPs composed of 80 µg/mL collagen-IV, 10 µg/mL laminin-521, and 10 µg/mL nidogen-1. Sham-treated islets (STIs) cultured without ECMPs or WPM-gel served as controls. Post-culture characterisation included IEQ yield or islet number (IN), viability (FDA-PI), early plus late apoptosis (annexin V-PI), glucose stimulation index (SI: 2 vs 20 vs 2 mM) and reactive oxygen species production. All parameters were normalised to IEQ, related to pre-culture data if appropriate and presented as mean ± SEM. Statistical analysis was performed by Friedman test and Dunn’s multiple comparison. Results Post-culture recovery was highest when hypoxic human islets were cultured in WPM-gel and compared with STIs (65±10% vs 38±10%, p<0.01). Although fragmentation (IN/IEQ ratio) increased after all treatments, this increase was lowest in the presence of WPM-gel (0.62±0.05 vs 0.80±0.14 vs 0.93±0.27, NS). Pre-culture viability was nearly completely preserved when human ECMPs (99±10% vs 79±10%, p<0.01) or WPM-gel (92±8%, p<0.05) were administered. Reactive oxygen species production in STIs increased nearly three-fold (127±15 AU/IEQ) but was halved in the presence of ECMPs (61±14 AU/IEQ, p<0.01) or WPM-gel (65±18 AU/IEQ, p<0.05). While initial early apoptosis remained stable when human islets were treated with human ECMPs (90±13% vs 136±14%, p<0.01) or WPM-gel (84±10%, p<0.01), apo-necrosis increased substantially in the presence of human ECMPs (172±33%, NS) or WPM-gel (154±195 vs 214±24%, p<0.05). Glucose-stimulated islets did not respond adequately after sham-treatment (SI 0.85±0.14). In contrast, supplementation with human ECMPs (1.29±0.09, p<0.05) or WPM-gel (1.34±0.09, p<0.01) preserved the physiological insulin response during hypoxia. Overall survival, considering the recovery of viable cells only, was increased by human ECMPs (56±8% vs 34±8%, p<0.01) or WPM-gel (58±8%, p<0.01). Conclusion This initial study presents a new approach to protect human islets from hypoxia-induced damage by supplementing culture media with selected ECMPs or with the whole pancreatic ECM. We assume, that the outcome of our approach will be further improved when the ECM is extracted from human pancreases. These promising findings can be used to develop advanced culture media and innovative encapsulation techniques to protect transplanted islets.

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WHOLE PORCINE PANCREATIC EXTRACELLULAR MATRIX-BASED HYDROGEL INCREASES SURVIVAL OF HUMAN ISLETS EXPOSED TO HYPOXIA

Transplantation Journal ◽

10.1097/01.tp.0000701572.74050.f7 ◽

2020 ◽

Vol 104 (S3) ◽

pp. S560-S560

Author(s):

Daniel Brandhorst ◽

Limor Baruch ◽

Heide Brandhorst ◽

Stasia Krishtul ◽

Marcelle Machluf ◽

...

Keyword(s):

Extracellular Matrix ◽

Human Islets

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Mesenchymal stromal cells improve human islet function through released products and extracellular matrix

Clinical Science ◽

10.1042/cs20171251 ◽

2017 ◽

Vol 131 (23) ◽

pp. 2835-2845 ◽

Cited By ~ 36

Author(s):

Ahmed A. Arzouni ◽

Andreia Vargas-Seymour ◽

Chloe L. Rackham ◽

Paramjeet Dhadda ◽

Guo-Cai Huang ◽

...

Keyword(s):

Extracellular Matrix ◽

Mesenchymal Stromal Cells ◽

Stromal Cells ◽

Human Islets ◽

Human Islet ◽

Human Mscs ◽

Islet Function ◽

Secretory Function ◽

Beneficial Effects

Aims: The aims of the present study were (i) to determine whether the reported beneficial effects of mesenchymal stromal cells (MSCs) on mouse islet function extend to clinically relevant human tissues (islets and MSCs), enabling translation into improved protocols for clinical human islet transplantation; and (ii) to identify possible mechanisms through which human MSCs influence human islet function. Materials and methods: Human islets were co-cultured with human adipose tissue-derived MSCs (hASCs) or pre-treated with its products – extracellular matrix (ECM) and annexin A1 (ANXA1). Mouse islets were pre-treated with mouse MSC-derived ECM. Islet insulin secretory function was assessed in vitro by radioimmunoassay. Quantitative RT-PCR was used to screen human adipMSCs for potential ligands of human islet G-protein-coupled receptors. Results: We show that co-culture with hASCs improves human islet secretory function in vitro, as measured by glucose-stimulated insulin secretion, confirming previous reports using rodent tissues. Furthermore, we demonstrate that these beneficial effects on islet function can be partly attributed to the MSC-derived products ECM and ANXA1. Conclusions: Our results suggest that hASCs have the potential to improve the quality of human islets isolated for transplantation therapy of Type 1 diabetes. Furthermore, it may be possible to achieve improvements in human islet quality in a cell-free culture system by using the MSC-derived products ANXA1 and ECM.

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Cardiac myocytes cultured on a basement membrane extract of the ehs tumor

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100142979 ◽

1986 ◽

Vol 44 ◽

pp. 270-271

Author(s):

L. Terracio ◽

A. Dewey ◽

K. Rubin ◽

T.K. Borg

Keyword(s):

Extracellular Matrix ◽

Basement Membrane ◽

Cardiac Myocytes ◽

Normal Tissue ◽

Cell Spreading ◽

Collagen Iv ◽

Basement Membrane Extract ◽

Membrane Extract ◽

Growth Development ◽

Multicellular Organisms

The recognition and interaction of cells with the extracellular matrix (ECM) effects the normal physiology as well as the pathology of all multicellular organisms. These interactions have been shown to influence the growth, development, and maintenance of normal tissue function. In previous studies, we have shown that neonatal cardiac myocytes specifically interacts with a variety of ECM components including fibronectin, laminin, and collagens I, III and IV. Culturing neonatal myocytes on laminin and collagen IV induces an increased rate of both cell spreading and sarcomerogenesis.

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Neutrophil migration through in vitro interstitial matrix

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100124872 ◽

1992 ◽

Vol 50 (1) ◽

pp. 894-895

Author(s):

J. Roemer ◽

S.R. Simon

Keyword(s):

Extracellular Matrix ◽

Smooth Muscle ◽

Cell Migration ◽

Smooth Muscle Cells ◽

Inflammatory Cell ◽

Neutrophil Migration ◽

Culture Conditions ◽

Aortic Smooth Muscle ◽

Specific Culture

We are developing an in vitro interstitial extracellular matrix (ECM) system for study of inflammatory cell migration. Falcon brand Cyclopore membrane inserts of various pore sizes are used as a support substrate for production of ECM by R22 rat aortic smooth muscle cells. Under specific culture conditions these cells produce a highly insoluble matrix consisting of typical interstitial ECM components, i.e.: types I and III collagen, elastin, proteoglycans and fibronectin.

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The extracellular matrix of echinoderm and amphibian eggs: Visualization in quick-frozen, deep-etched, and rotary-shadowed specimens

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010015784x ◽

1990 ◽

Vol 48 (3) ◽

pp. 60-61

Author(s):

Barry Bonnell ◽

Carolyn Larabell ◽

Douglas Chandler

Keyword(s):

Extracellular Matrix ◽

Plasma Membrane ◽

Sea Urchin ◽

Crystalline Structure ◽

Cortical Granule ◽

Two Dimensional ◽

Small Peptides ◽

Deep Etching ◽

Quick Freezing ◽

Acrosomal Reaction

Eggs of many species including those of echinoderms, amphibians and mammals exhibit an extensive extracellular matrix (ECM) that is important both in the reception of sperm and in providing a block to polyspermy after fertilization.In sea urchin eggs there are two distinctive coats, the vitelline layer which contains glycoprotein sperm receptors and the jelly layer that contains fucose sulfate glycoconjugates which trigger the acrosomal reaction and small peptides which act as chemoattractants for sperm. The vitelline layer (VL), as visualized by quick-freezing, deep-etching, and rotary-shadowing (QFDE-RS), is a fishnet-like structure, anchored to the plasma membrane by short posts. Orbiting above the VL are horizontal filaments which are thought to anchor the thicker jelly layer to the egg. Upon fertilization, the VL elevates and is transformed by cortical granule secretions into the fertilization envelope (FE). The rounded casts of microvilli in the VL are transformed into angular peaks and the envelope becomes coated inside and out with sheets of paracrystalline protein having a quasi-two dimensional crystalline structure.

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Extracellular matrix: the gatekeeper of tumor angiogenesis

Biochemical Society Transactions ◽

10.1042/bst20190653 ◽

2019 ◽

Vol 47 (5) ◽

pp. 1543-1555 ◽

Cited By ~ 10

Author(s):

Maurizio Mongiat ◽

Simone Buraschi ◽

Eva Andreuzzi ◽

Thomas Neill ◽

Renato V. Iozzo

Keyword(s):

Extracellular Matrix ◽

Tumor Angiogenesis ◽

Signaling Cascades ◽

Cancer Growth ◽

Cell Behavior ◽

Metastatic Progression ◽

Surface Receptors ◽

The Matrix ◽

Multiple Signaling

Abstract The extracellular matrix is a network of secreted macromolecules that provides a harmonious meshwork for the growth and homeostatic development of organisms. It conveys multiple signaling cascades affecting specific surface receptors that impact cell behavior. During cancer growth, this bioactive meshwork is remodeled and enriched in newly formed blood vessels, which provide nutrients and oxygen to the growing tumor cells. Remodeling of the tumor microenvironment leads to the formation of bioactive fragments that may have a distinct function from their parent molecules, and the balance among these factors directly influence cell viability and metastatic progression. Indeed, the matrix acts as a gatekeeper by regulating the access of cancer cells to nutrients. Here, we will critically evaluate the role of selected matrix constituents in regulating tumor angiogenesis and provide up-to-date information concerning their primary mechanisms of action.

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