1
|
Lee AL, Lee SH, Nguyen H, Cahill M, Kappel E, Pomerantz WCK, Haynes CL. Investigation of the Post-Synthetic Confinement of Fluorous Liquids Inside Mesoporous Silica Nanoparticles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:5222-5231. [PMID: 33886317 PMCID: PMC9682517 DOI: 10.1021/acs.langmuir.1c00167] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Perfluorocarbon (PFC) filled nanoparticles are increasingly being investigated for various biomedical applications. Common approaches for PFC liquid entrapment involve surfactant-based emulsification and Pickering emulsions. Alternatively, PFC liquids are capable of being entrapped inside hollow nanoparticles via a postsynthetic loading method (PSLM). While the methodology for the PSLM is straightforward, the effect each loading parameter has on the PFC entrapment has yet to be investigated. Previous work revealed incomplete filling of the hollow nanoparticles. Changing the loading parameters was expected to influence the ability of the PFC to fill the core of the nanoparticles. Hence, it would be possible to model the loading mechanism and determine the influence each factor has on PFC entrapment by tracking the change in loading yield and efficiency of PFC-filled nanoparticles. Herein, neat PFC liquid was loaded into silica nanoparticles and extracted into aqueous phases while varying the sonication time, concentration of nanoparticles, volume ratio between aqueous and fluorous phases, and pH of the extraction water. Loading yields and efficiency were determined via 19F nuclear magnetic resonance and N2 physisorption isotherms. Sonication time was indicated to have the strongest correlation to loading yield and efficiency; however, method validation revealed that the current model does not fully explain the loading capabilities of the PSLM. Confounding variables and more finely controlled parameters need to be considered to better predict the behavior and loading capacity by the PSLM and warrants further study.
Collapse
Affiliation(s)
- Amani L Lee
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Sang-Hyuk Lee
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Huan Nguyen
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Meghan Cahill
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Elaine Kappel
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - William C K Pomerantz
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Christy L Haynes
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| |
Collapse
|
2
|
Mitchelson F, Safley SA, Gordon K, Weber CJ, Sambanis A. Peritoneal dissolved oxygen and function of encapsulated adult porcine islets transplanted in streptozotocin diabetic mice. Xenotransplantation 2021; 28:e12673. [PMID: 33522023 DOI: 10.1111/xen.12673] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 12/06/2020] [Accepted: 12/24/2020] [Indexed: 01/02/2023]
Abstract
BACKGROUND Alginate-encapsulated islet xenografts have restored normoglycemia in diabetic animals for various periods of time. Plausible mechanisms of graft failure in vivo include immune rejection and hypoxia. We sought to understand the effects of encapsulated adult porcine islet (API) dosage on the peritoneal dissolved oxygen (DO) level in correlation to the achieved glycemic regulation in diabetic mice. METHODS Adult porcine islets encapsulated in barium alginate were transplanted intraperitoneally in streptozotocin diabetic BALB/c mice at 6000 and 4000 islet equivalents (IEQ) and in normal mice at 500 IEQ; APIs encapsulated in calcium alginate were transplanted at 6000 IEQ in diabetic mice. In all cases, cell-free barium alginate capsules containing a perfluorocarbon emulsion were co-implanted for DO measurements using 19 F NMR spectroscopy. Blood glucose levels and peritoneal DO were measured over 60 days or until graft failure. Explanted capsules were evaluated microscopically and histologically. RESULTS Both barium and calcium alginate-encapsulated APIs at 6000 IEQ reversed diabetes until day 60; barium alginate-encapsulated APIs at 4000 IEQ also reversed diabetes but with a higher failure rate. Transplanted APIs significantly reduced the peritoneal DO, approximately in a dose-dependent manner. The number of viable islets and the insulin content per capsule decreased over time. Capsules retrieved from normoglycemic mice exhibited minimal host cell adherence. CONCLUSIONS Transplantation of encapsulated APIs can reduce peritoneal DO to severely hypoxic levels. Although normoglycemia could be maintained within the study period, the DO levels suggest that hypoxia is a factor contributing to loss of islet viability and insulin secretion with time in mice.
Collapse
Affiliation(s)
- Fernie Mitchelson
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Susan A Safley
- Department of General Surgery, Emory University, Atlanta, GA, USA
| | - Kereen Gordon
- Department of General Surgery, Emory University, Atlanta, GA, USA
| | - Collin J Weber
- Department of General Surgery, Emory University, Atlanta, GA, USA
| | - Athanassios Sambanis
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, USA.,Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, Atlanta, GA, USA.,W.M. Keck Foundation, Los Angeles, CA, USA
| |
Collapse
|
3
|
Safley SA, Graham ML, Weegman BP, Einstein SA, Barber GF, Janecek JJ, Mutch LA, Singh A, Ramachandran S, Garwood M, Sambanis A, Papas KK, Hering BJ, Weber CJ. Noninvasive Fluorine-19 Magnetic Resonance Relaxometry Measurement of the Partial Pressure of Oxygen in Acellular Perfluorochemical-loaded Alginate Microcapsules Implanted in the Peritoneal Cavity of Nonhuman Primates. Transplantation 2020; 104:259-269. [PMID: 31385927 PMCID: PMC6994361 DOI: 10.1097/tp.0000000000002896] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND We have utilized a noninvasive technique for measuring the partial pressure of oxygen (pO2) in alginate microcapsules implanted intraperitoneally in healthy nonhuman primates (NHPs). Average pO2 is important for determining if a transplant site and capsules with certain passive diffusion characteristics can support the islet viability, metabolic activity, and dose necessary to reverse diabetes. METHODS Perfluoro-15-crown-5-ether alginate capsules were infused intraperitoneally into 3 healthy NHPs. Peritoneal pO2 levels were measured on days 0 and 7 using fluorine-19 magnetic resonance relaxometry and a fiber-optic probe. Fluorine-19 MRI was used to determine the locations of capsules within the peritoneal space on days 0 and 7. Gross and histologic evaluations of the capsules were used to assess their biocompatibility postmortem. RESULTS At day 0 immediately after infusion of capsules equilibrated to room air, capsules were concentrated near the infusion site, and the pO2 measurement using magnetic resonance relaxometry was 147 ± 9 mm Hg. On day 7 after capsules were dispersed throughout the peritoneal cavity, the pO2 level was 61 ± 11 mm Hg. Measurements using the fiber-optic oxygen sensor were 132 ± 7.5 mm Hg (day 0) and 89 ± 6.1 mm Hg (day 7). Perfluoro-15-crown-5-ether capsules retrieved on day 7 were intact and free-floating without host cell attachment, although the numbers of peritoneal CD20 B cells, CD4 and CD8 T cells, and CD14 macrophages increased consistent with a mild foreign body reaction. CONCLUSIONS The peritoneal pO2 of normal NHPs is relatively low and we predict would decrease further when encapsulated islets are transplanted intraperitoneally.
Collapse
Affiliation(s)
| | - Melanie L. Graham
- Preclinical Research Center, Department of Surgery, University of Minnesota, St. Paul, MN
| | - Bradley P. Weegman
- Sylvatica Biotech, Inc., Charleston, SC
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, MN
| | - Samuel A. Einstein
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, MN
- Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, TX
| | | | - Jody J. Janecek
- Preclinical Research Center, Department of Surgery, University of Minnesota, St. Paul, MN
| | - Lucas A. Mutch
- Preclinical Research Center, Department of Surgery, University of Minnesota, St. Paul, MN
| | - Amar Singh
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota, Minneapolis, MN
| | | | - Michael Garwood
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, MN
| | | | | | - Bernhard J. Hering
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota, Minneapolis, MN
| | | |
Collapse
|
4
|
Simultaneous spatiotemporal tracking and oxygen sensing of transient implants in vivo using hot-spot MRI and machine learning. Proc Natl Acad Sci U S A 2019; 116:4861-4870. [PMID: 30808810 DOI: 10.1073/pnas.1815909116] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
A varying oxygen environment is known to affect cellular function in disease as well as activity of various therapeutics. For transient structures, whether they are unconstrained therapeutic transplants, migrating cells during tumor metastasis, or cell populations induced by an immunological response, the role of oxygen in their fate and function is known to be pivotal albeit not well understood in vivo. To address such a challenge in the case of generation of a bioartificial pancreas, we have combined fluorine magnetic resonance imaging and unsupervised machine learning to monitor over time the spatial arrangement and the oxygen content of implants encapsulating pancreatic islets that are unconstrained in the intraperitoneal (IP) space of healthy and diabetic mice. Statistically significant trends in the postimplantation temporal dependence of oxygen content between aggregates of 0.5-mm or 1.5-mm alginate microcapsules were identified in vivo by looking at their dispersity as well as arrangement in clusters of different size and estimating oxygen content on a pixel-by-pixel basis from thousands of 2D images. Ultimately, we found that this dependence is stronger for decreased implant capsule size consistent with their tendency to also induce a larger immunological response. Beyond the bioartificial pancreas, this work provides a framework for the simultaneous spatiotemporal tracking and oxygen sensing of other cell populations and biomaterials that change over time to better understand and improve therapeutic design across diverse applications such as cellular transplant therapy, treatments preventing metastatic formation, and modulators for improving immunologic response, for all of which oxygen is a major mechanistic component.
Collapse
|
5
|
Bochenek MA, Veiseh O, Vegas AJ, McGarrigle JJ, Qi M, Marchese E, Omami M, Doloff JC, Mendoza-Elias J, Nourmohammadzadeh M, Khan A, Yeh CC, Xing Y, Isa D, Ghani S, Li J, Landry C, Bader AR, Olejnik K, Chen M, Hollister-Lock J, Wang Y, Greiner DL, Weir GC, Strand BL, Rokstad AMA, Lacik I, Langer R, Anderson DG, Oberholzer J. Alginate encapsulation as long-term immune protection of allogeneic pancreatic islet cells transplanted into the omental bursa of macaques. Nat Biomed Eng 2018; 2:810-821. [PMID: 30873298 PMCID: PMC6413527 DOI: 10.1038/s41551-018-0275-1] [Citation(s) in RCA: 206] [Impact Index Per Article: 34.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Accepted: 07/12/2018] [Indexed: 12/29/2022]
Abstract
The transplantation of pancreatic islet cells could restore glycaemic control in patients with type-I diabetes. Microspheres for islet encapsulation have enabled long-term glycaemic control in diabetic rodent models; yet human patients transplanted with equivalent microsphere formulations have experienced only transient islet-graft function, owing to a vigorous foreign-body reaction (FBR), to pericapsular fibrotic overgrowth (PFO) and, in upright bipedal species, to the sedimentation of the microspheres within the peritoneal cavity. Here, we report the results of the testing, in non-human primate (NHP) models, of seven alginate formulations that were efficacious in rodents, including three that led to transient islet-graft function in clinical trials. Although one month post-implantation all formulations elicited significant FBR and PFO, three chemically modified, immune-modulating alginate formulations elicited reduced FBR. In conjunction with a minimally invasive transplantation technique into the bursa omentalis of NHPs, the most promising chemically modified alginate derivative (Z1-Y15) protected viable and glucose-responsive allogeneic islets for 4 months without the need for immunosuppression. Chemically modified alginate formulations may enable the long-term transplantation of islets for the correction of insulin deficiency.
Collapse
Affiliation(s)
- Matthew A Bochenek
- Division of Transplantation, Department of Surgery, University of Illinois at Chicago, Chicago, IL, USA
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, USA
- David H Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Anesthesiology, Boston Children's Hospital, Boston, MA, USA
| | - Omid Veiseh
- David H Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Anesthesiology, Boston Children's Hospital, Boston, MA, USA
- Sigilon Therapeutics, Inc., Cambridge, MA, USA
- Department of Bioengineering, Rice University, Houston, TX, USA
| | - Arturo J Vegas
- David H Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Anesthesiology, Boston Children's Hospital, Boston, MA, USA
- Chemistry Department, Boston University, Boston, MA, USA
| | - James J McGarrigle
- Division of Transplantation, Department of Surgery, University of Illinois at Chicago, Chicago, IL, USA
- CellTrans Inc., Chicago, IL, USA
| | - Meirigeng Qi
- Division of Transplantation, Department of Surgery, University of Illinois at Chicago, Chicago, IL, USA
| | - Enza Marchese
- Division of Transplantation, Department of Surgery, University of Illinois at Chicago, Chicago, IL, USA
| | - Mustafa Omami
- Division of Transplantation, Department of Surgery, University of Illinois at Chicago, Chicago, IL, USA
| | - Joshua C Doloff
- David H Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Anesthesiology, Boston Children's Hospital, Boston, MA, USA
| | - Joshua Mendoza-Elias
- Division of Transplantation, Department of Surgery, University of Illinois at Chicago, Chicago, IL, USA
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, USA
| | - Mohammad Nourmohammadzadeh
- Division of Transplantation, Department of Surgery, University of Illinois at Chicago, Chicago, IL, USA
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, USA
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA
| | - Arshad Khan
- Division of Transplantation, Department of Surgery, University of Illinois at Chicago, Chicago, IL, USA
| | - Chun-Chieh Yeh
- Division of Transplantation, Department of Surgery, University of Illinois at Chicago, Chicago, IL, USA
| | - Yuan Xing
- Division of Transplantation, Department of Surgery, University of Illinois at Chicago, Chicago, IL, USA
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, USA
- Department of Surgery and Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Douglas Isa
- Division of Transplantation, Department of Surgery, University of Illinois at Chicago, Chicago, IL, USA
- CellTrans Inc., Chicago, IL, USA
| | - Sofia Ghani
- Division of Transplantation, Department of Surgery, University of Illinois at Chicago, Chicago, IL, USA
- CellTrans Inc., Chicago, IL, USA
| | - Jie Li
- David H Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Anesthesiology, Boston Children's Hospital, Boston, MA, USA
- Sigilon Therapeutics, Inc., Cambridge, MA, USA
- Department of Bioengineering, Rice University, Houston, TX, USA
| | - Casey Landry
- David H Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Anesthesiology, Boston Children's Hospital, Boston, MA, USA
| | - Andrew R Bader
- David H Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Anesthesiology, Boston Children's Hospital, Boston, MA, USA
| | - Karsten Olejnik
- David H Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Anesthesiology, Boston Children's Hospital, Boston, MA, USA
- Sigilon Therapeutics, Inc., Cambridge, MA, USA
- Department of Bioengineering, Rice University, Houston, TX, USA
| | - Michael Chen
- David H Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Anesthesiology, Boston Children's Hospital, Boston, MA, USA
| | - Jennifer Hollister-Lock
- Section on Islet Cell and Regenerative Biology, Research Division, Joslin Diabetes Center, Boston, MA, USA
| | - Yong Wang
- Division of Transplantation, Department of Surgery, University of Illinois at Chicago, Chicago, IL, USA
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, USA
- Department of Surgery and Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Dale L Greiner
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Gordon C Weir
- Section on Islet Cell and Regenerative Biology, Research Division, Joslin Diabetes Center, Boston, MA, USA
| | - Berit Løkensgard Strand
- Department of Biotechnology and Food Sciences, Norwegian University of Science and Technology, Trondheim, Norway
| | - Anne Mari A Rokstad
- Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
- Centre of Obesity, Clinic of Surgery, St. Olavs University Hospital, Trondheim, Norway
| | - Igor Lacik
- Polymer Institute, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Robert Langer
- David H Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Anesthesiology, Boston Children's Hospital, Boston, MA, USA
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA
- Division of Health Science Technology, Massachusetts Institute of Technology, Cambridge, MA, USA
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Daniel G Anderson
- David H Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Department of Anesthesiology, Boston Children's Hospital, Boston, MA, USA.
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA.
- Division of Health Science Technology, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA.
| | - Jose Oberholzer
- Division of Transplantation, Department of Surgery, University of Illinois at Chicago, Chicago, IL, USA.
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, USA.
- Department of Surgery and Biomedical Engineering, University of Virginia, Charlottesville, VA, USA.
| |
Collapse
|
6
|
Safley SA, Kenyon NS, Berman DM, Barber GF, Willman M, Duncanson S, Iwakoshi N, Holdcraft R, Gazda L, Thompson P, Badell IR, Sambanis A, Ricordi C, Weber CJ. Microencapsulated adult porcine islets transplanted intraperitoneally in streptozotocin-diabetic non-human primates. Xenotransplantation 2018; 25:e12450. [PMID: 30117193 DOI: 10.1111/xen.12450] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 05/18/2018] [Accepted: 06/26/2018] [Indexed: 12/21/2022]
Abstract
BACKGROUND Xenogeneic donors would provide an unlimited source of islets for the treatment of type 1 diabetes (T1D). The goal of this study was to assess the function of microencapsulated adult porcine islets (APIs) transplanted ip in streptozotocin (STZ)-diabetic non-human primates (NHPs) given targeted immunosuppression. METHODS APIs were encapsulated in: (a) single barium-gelled alginate capsules or (b) double alginate capsules with an inner, islet-containing compartment and a durable, biocompatible outer alginate layer. Immunosuppressed, streptozotocin-diabetic NHPs were transplanted ip with encapsulated APIs, and graft function was monitored by measuring blood glucose, %HbA1c, and porcine C-peptide. At graft failure, explanted capsules were assessed for biocompatibility and durability plus islet viability and functionality. Host immune responses were evaluated by phenotyping peritoneal cell populations, quantitation of peritoneal cytokines and chemokines, and measurement of anti-porcine IgG and IgM plus anti-Gal IgG. RESULTS NHP recipients had reduced hyperglycemia, decreased exogenous insulin requirements, and lower percent hemoglobin A1c (%HbA1c) levels. Porcine C-peptide was detected in plasma of all recipients, but these levels diminished with time. However, relatively high levels of porcine C-peptide were detected locally in the peritoneal graft site of some recipients at sacrifice. IV glucose tolerance tests demonstrated metabolic function, but the grafts eventually failed in all diabetic NHPs regardless of the type of encapsulation or the host immunosuppression regimen. Explanted microcapsules were intact, "clean," and free-floating without evidence of fibrosis at graft failure, and some reversed diabetes when re-implanted ip in diabetic immunoincompetent mice. Histology of explanted capsules showed scant evidence of a host cellular response, and viable islets could be found. Flow cytometric analyses of peritoneal cells and peripheral blood showed similarly minimal evidence of a host immune response. Preformed anti-porcine IgG and IgM antibodies were present in recipient plasma, but these levels did not rise post-transplant. Peritoneal graft site cytokine or chemokine levels were equivalent to normal controls, with the exception of minimal elevation observed for IL-6 or IL-1β, GRO-α, I-309, IP-10, and MCP-1. However, we found central necrosis in many of the encapsulated islets after graft failure, and explanted islets expressed endogenous markers of hypoxia (HIF-1α, osteopontin, and GLUT-1), suggesting a role for non-immunologic factors, likely hypoxia, in graft failure. CONCLUSIONS With donor xenoislet microencapsulation and host immunosuppression, APIs corrected hyperglycemia after ip transplantation in STZ-diabetic NHPs in the short term. The islet xenografts lost efficacy gradually, but at graft failure, some viable islets remained, substantial porcine C-peptide was detected in the peritoneal graft site, and there was very little evidence of a host immune response. We postulate that chronic effects of non-immunologic factors, such as in vivo hypoxic and hyperglycemic conditions, damaged the encapsulated islet xenografts. To achieve long-term function, new approaches must be developed to prevent this damage, for example, by increasing the oxygen supply to microencapsulated islets in the ip space.
Collapse
Affiliation(s)
- Susan A Safley
- Department of Surgery, Emory University, Atlanta, Georgia
| | - Norma S Kenyon
- Diabetes Research Institute, Miami, Florida.,Department of Surgery, Miller School of Medicine, University of Miami, Miami, Florida.,Department of Microbiology & Immunology, Miller School of Medicine, University of Miami, Miami, Florida.,Department of Pathology, Miller School of Medicine, University of Miami, Miami, Florida
| | - Dora M Berman
- Diabetes Research Institute, Miami, Florida.,Department of Surgery, Miller School of Medicine, University of Miami, Miami, Florida.,Department of Microbiology & Immunology, Miller School of Medicine, University of Miami, Miami, Florida.,Department of Pathology, Miller School of Medicine, University of Miami, Miami, Florida
| | | | | | - Stephanie Duncanson
- Department of Biomedical Engineering, School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia
| | - Neal Iwakoshi
- Department of Surgery, Emory University, Atlanta, Georgia
| | | | | | - Peter Thompson
- Department of Surgery, Emory University, Atlanta, Georgia
| | - I Raul Badell
- Department of Surgery, Emory University, Atlanta, Georgia
| | - Athanassios Sambanis
- Department of Biomedical Engineering, School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia
| | - Camillo Ricordi
- Diabetes Research Institute, Miami, Florida.,Department of Surgery, Miller School of Medicine, University of Miami, Miami, Florida.,Department of Microbiology & Immunology, Miller School of Medicine, University of Miami, Miami, Florida.,Department of Pathology, Miller School of Medicine, University of Miami, Miami, Florida.,Department of Medicine, Miller School of Medicine, University of Miami, Miami, Florida
| | - Collin J Weber
- Department of Surgery, Emory University, Atlanta, Georgia
| |
Collapse
|
7
|
Current advanced therapy cell-based medicinal products for type-1-diabetes treatment. Int J Pharm 2018; 543:107-120. [PMID: 29597032 DOI: 10.1016/j.ijpharm.2018.03.041] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 03/19/2018] [Accepted: 03/24/2018] [Indexed: 12/11/2022]
Abstract
In the XXI century diabetes mellitus has become one of the main threats to human health with higher incidence in regions such as Europe and North America. Type 1 diabetes mellitus (T1DM) occurs as a consequence of the immune-mediated destruction of insulin producing β-cells located in the endocrine part of the pancreas, the islets of Langerhans. The administration of exogenous insulin through daily injections is the most prominent treatment for T1DM but its administration is frequently associated to failure in glucose metabolism control, finally leading to hyperglycemia episodes. Other approaches have been developed in the past decades, such as whole pancreas and islet allotransplantation, but they are restricted to patients who exhibit frequent episodes of hypoglycemia or renal failure because the lack of donors and islet survival. Moreover, patients transplanted with either whole pancreas or islets require of immune suppression to avoid the rejection of the transplant. Currently, advanced therapy medicinal products (ATMP), such as implantable devices, have been developed in order to reduce immune rejection response while increasing cell survival. To overcome these issues, ATMPs must promote vascularization, guaranteeing the nutritional contribution, while providing O2 until vasculature can surround the device. Moreover, it should help in the immune-protection to avoid acute and chronic rejection. The transplanted cells or islets should be embedded within biomaterials with tunable properties like injectability, stiffness and porosity mimicking natural ECM structural characteristics. And finally, an infinitive cell source that solves the donor scarcity should be found such as insulin producing cells derived from mesenchymal stem cells (MSCs), embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs). Several companies have registered their ATMPs and future studies envision new prototypes. In this review, we will discuss the mechanisms and etiology of diabetes, comparing the clinical trials in the last decades in order to define the main characteristics for future ATMPs.
Collapse
|
8
|
Einstein SA, Weegman BP, Firpo MT, Papas KK, Garwood M. Development and Validation of Noninvasive Magnetic Resonance Relaxometry for the In Vivo Assessment of Tissue-Engineered Graft Oxygenation. Tissue Eng Part C Methods 2016; 22:1009-1017. [PMID: 27758135 PMCID: PMC5116663 DOI: 10.1089/ten.tec.2016.0106] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 09/26/2016] [Indexed: 11/12/2022] Open
Abstract
Techniques to monitor the oxygen partial pressure (pO2) within implanted tissue-engineered grafts (TEGs) are critically necessary for TEG development, but current methods are invasive and inaccurate. In this study, we developed an accurate and noninvasive technique to monitor TEG pO2 utilizing proton (1H) or fluorine (19F) magnetic resonance spectroscopy (MRS) relaxometry. The value of the spin-lattice relaxation rate constant (R1) of some biocompatible compounds is sensitive to dissolved oxygen (and temperature), while insensitive to other external factors. Through this physical mechanism, MRS can measure the pO2 of implanted TEGs. We evaluated six potential MRS pO2 probes and measured their oxygen and temperature sensitivities and their intrinsic R1 values at 16.4 T. Acellular TEGs were constructed by emulsifying porcine plasma with perfluoro-15-crown-5-ether, injecting the emulsion into a macroencapsulation device, and cross-linking the plasma with a thrombin solution. A multiparametric calibration equation containing R1, pO2, and temperature was empirically generated from MRS data and validated with fiber optic (FO) probes in vitro. TEGs were then implanted in a dorsal subcutaneous pocket in a murine model and evaluated with MRS up to 29 days postimplantation. R1 measurements from the TEGs were converted to pO2 values using the established calibration equation and these in vivo pO2 measurements were simultaneously validated with FO probes. Additionally, MRS was used to detect increased pO2 within implanted TEGs that received supplemental oxygen delivery. Finally, based on a comparison of our MRS data with previously reported data, ultra-high-field (16.4 T) is shown to have an advantage for measuring hypoxia with 19F MRS. Results from this study show MRS relaxometry to be a precise, accurate, and noninvasive technique to monitor TEG pO2 in vitro and in vivo.
Collapse
Affiliation(s)
- Samuel A. Einstein
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, Minnesota
| | - Bradley P. Weegman
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, Minnesota
| | - Meri T. Firpo
- Department of Medicine, Stem Cell Institute, University of Minnesota, Minneapolis, Minnesota
| | | | - Michael Garwood
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, Minnesota
| |
Collapse
|
9
|
Schmieder AH, Caruthers SD, Keupp J, Wickline SA, Lanza GM. Recent Advances in 19Fluorine Magnetic Resonance Imaging with Perfluorocarbon Emulsions. ENGINEERING (BEIJING, CHINA) 2015; 1:475-489. [PMID: 27110430 PMCID: PMC4841681 DOI: 10.15302/j-eng-2015103] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The research roots of 19fluorine (19F) magnetic resonance imaging (MRI) date back over 35 years. Over that time span, 1H imaging flourished and was adopted worldwide with an endless array of applications and imaging approaches, making magnetic resonance an indispensable pillar of biomedical diagnostic imaging. For many years during this timeframe, 19F imaging research continued at a slow pace as the various attributes of the technique were explored. However, over the last decade and particularly the last several years, the pace and clinical relevance of 19F imaging has exploded. In part, this is due to advances in MRI instrumentation, 19F/1H coil designs, and ultrafast pulse sequence development for both preclinical and clinical scanners. These achievements, coupled with interest in the molecular imaging of anatomy and physiology, and combined with a cadre of innovative agents, have brought the concept of 19F into early clinical evaluation. In this review, we attempt to provide a slice of this rich history of research and development, with a particular focus on liquid perfluorocarbon compound-based agents.
Collapse
Affiliation(s)
- Anne H. Schmieder
- Division of Cardiology, Washington University School of Medical, St. Louis, MO 63110, USA
| | - Shelton D. Caruthers
- Toshiba Medical Research Institute USA, Inc., Cleveland, OH 44143, USA
- Department of Biomedical Engineering, Washington University, St. Louis, MO 63130, USA
| | - Jochen Keupp
- Philips Research Hamburg, Hamburg 22335, Germany
| | - Samuel A. Wickline
- Division of Cardiology, Washington University School of Medical, St. Louis, MO 63110, USA
| | - Gregory M. Lanza
- Division of Cardiology, Washington University School of Medical, St. Louis, MO 63110, USA
- Correspondence author.
| |
Collapse
|
10
|
Abstract
BACKGROUND Cell-based insulin therapies can potentially improve glycemic regulation in insulin-dependent diabetic patients. Enteroendocrine cells engineered to secrete recombinant insulin have exhibited glycemic efficacy, but have been primarily studied as uncontrollable growth systems in immune incompetent mice. Furthermore, reports suggest that suboptimal insulin secretion remains a barrier to expanded application. METHODS Genetic and tissue engineering strategies were applied to improve recombinant insulin secretion from intestinal L-cells on both a per-cell and per-graft basis. Transduction of insulin-expressing GLUTag L-cells with lentivirus carrying an additional human insulin gene-enhanced secretion twofold. We infected cells with lentivirus expressing a luciferase reporter gene to track cell survival in vivo. To provide a growth-controlled and immune protective environment without affecting secretory capacity, cells were microencapsulated in barium alginate. Approximately 9×10(7) microencapsulated cells were injected intraperitoneally in immune competent streptozotocin-induced diabetic mice for therapeutic efficacy evaluation. RESULTS Graft insulin secretion was increased to 16 to 24 mU insulin per day. Transient normoglycemia was achieved in treated mice two days after transplantation, and endogenous insulin was sufficient to sustain body weights of treated mice receiving minimal supplementation. CONCLUSION Glycemic efficacy of a bioartificial pancreas based on insulin-secreting enteroendocrine cells is insufficient as a standalone therapy, despite enhancement of graft insulin secretion capacity. Supplemental strategies to alleviate secretion limitations should be pursued.
Collapse
|
11
|
Tiernan AR, Sambanis A. Bioluminescence tracking of alginate micro-encapsulated cell transplants. J Tissue Eng Regen Med 2014; 11:501-508. [PMID: 25047413 DOI: 10.1002/term.1946] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 05/08/2014] [Accepted: 06/16/2014] [Indexed: 01/07/2023]
Abstract
Cell-based therapies to treat loss-of-function hormonal disorders such as diabetes and Parkinson's disease are routinely coupled with encapsulation strategies, but an understanding of when and why grafts fail in vivo is lacking. Consequently, investigators cannot clearly define the key factors that influence graft success. Although bioluminescence is a popular method to track the survival of free cells transplanted in preclinical models, little is known of the ability to use bioluminescence for real-time tracking of microencapsulated cells. Furthermore, the impact that dynamic imaging distances may have, due to freely-floating microcapsules in vivo, on cell survival monitoring is unknown. This work addresses these questions by applying bioluminescence to a pancreatic substitute based on microencapsulated cells. Recombinant insulin-secreting cells were transduced with a luciferase lentivirus and microencapsulated in Ba2+ crosslinked alginate for in vitro and in vivo studies. In vitro quantitative bioluminescence monitoring was possible and viable microencapsulated cells were followed in real time under both normoxic and anoxic conditions. Although in vivo dispersion of freely-floating microcapsules in the peritoneal cavity limited the analysis to a qualitative bioluminescence evaluation, signals consistently four orders of magnitude above background were clear indicators of temporal cell survival. Strong agreement between in vivo and in vitro cell proliferation over time was discovered by making direct bioluminescence comparisons between explanted microcapsules and parallel in vitro cultures. Broader application of this bioluminescence approach to retrievable transplants, in supplement to currently used end-point physiological tests, could improve understanding and accelerate development of cell-based therapies for critical clinical applications. Copyright © 2014 John Wiley & Sons, Ltd.
Collapse
Affiliation(s)
- Aubrey R Tiernan
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Athanassios Sambanis
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| |
Collapse
|
12
|
Colton CK. Oxygen supply to encapsulated therapeutic cells. Adv Drug Deliv Rev 2014; 67-68:93-110. [PMID: 24582600 DOI: 10.1016/j.addr.2014.02.007] [Citation(s) in RCA: 100] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Revised: 01/06/2014] [Accepted: 02/19/2014] [Indexed: 02/07/2023]
Abstract
Therapeutic cells encapsulated in immunobarrier devices have promise for treatment of a variety of human diseases without immunosuppression. The absence of sufficient oxygen supply to maintain viability and function of encapsulated tissue has been the most critical impediment to progress. Within the framework of oxygen supply limitations, we review the major issues related to development of these devices, primarily in the context of encapsulated islets of Langerhans for treating diabetes, including device designs and materials, supply of tissue, protection from immune rejection, and maintenance of cell viability and function. We describe various defensive measures investigated to enhance survival of transplanted tissue, and we review the diverse approaches to enhancement of oxygen transport to encapsulated tissue, including manipulation of diffusion distances and oxygen permeability of materials, induction of neovascularization with angiogenic factors and vascularizing membranes, and methods for increasing the oxygen concentration adjacent to encapsulated tissue so as to exceed that in the microvasculature. Recent developments, particularly in this latter area, suggest that the field is ready for clinical trials of encapsulated therapeutic cells to treat diabetes.
Collapse
|
13
|
Yu JX, Hallac RR, Chiguru S, Mason RP. New frontiers and developing applications in 19F NMR. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2013; 70:25-49. [PMID: 23540575 PMCID: PMC3613763 DOI: 10.1016/j.pnmrs.2012.10.001] [Citation(s) in RCA: 142] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Accepted: 10/23/2012] [Indexed: 05/06/2023]
Affiliation(s)
- Jian-Xin Yu
- Laboratory of Prognostic Radiology, Division of Advanced Radiological Sciences, Department of Radiology, UT Southwestern Medical Center, Dallas, Texas
| | - Rami R. Hallac
- Laboratory of Prognostic Radiology, Division of Advanced Radiological Sciences, Department of Radiology, UT Southwestern Medical Center, Dallas, Texas
| | - Srinivas Chiguru
- Laboratory of Prognostic Radiology, Division of Advanced Radiological Sciences, Department of Radiology, UT Southwestern Medical Center, Dallas, Texas
| | - Ralph P. Mason
- Laboratory of Prognostic Radiology, Division of Advanced Radiological Sciences, Department of Radiology, UT Southwestern Medical Center, Dallas, Texas
| |
Collapse
|
14
|
Duncanson S, Sambanis A. Dual factor delivery of CXCL12 and Exendin-4 for improved survival and function of encapsulated beta cells under hypoxic conditions. Biotechnol Bioeng 2013; 110:2292-300. [DOI: 10.1002/bit.24872] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Revised: 02/06/2013] [Accepted: 02/08/2013] [Indexed: 12/16/2022]
|
15
|
Yeatts AB, Choquette DT, Fisher JP. Bioreactors to influence stem cell fate: augmentation of mesenchymal stem cell signaling pathways via dynamic culture systems. Biochim Biophys Acta Gen Subj 2012; 1830:2470-80. [PMID: 22705676 DOI: 10.1016/j.bbagen.2012.06.007] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2012] [Revised: 05/03/2012] [Accepted: 06/07/2012] [Indexed: 01/09/2023]
Abstract
BACKGROUND Mesenchymal stem cells (MSCs) are a promising cell source for bone and cartilage tissue engineering as they can be easily isolated from the body and differentiated into osteoblasts and chondrocytes. A cell based tissue engineering strategy using MSCs often involves the culture of these cells on three-dimensional scaffolds; however the size of these scaffolds and the cell population they can support can be restricted in traditional static culture. Thus dynamic culture in bioreactor systems provides a promising means to culture and differentiate MSCs in vitro. SCOPE OF REVIEW This review seeks to characterize key MSC differentiation signaling pathways and provides evidence as to how dynamic culture is augmenting these pathways. Following an overview of dynamic culture systems, discussion will be provided on how these systems can effectively modify and maintain important culture parameters including oxygen content and shear stress. Literature is reviewed for both a highlight of key signaling pathways and evidence for regulation of these signaling pathways via dynamic culture systems. MAJOR CONCLUSIONS The ability to understand how these culture systems are affecting MSC signaling pathways could lead to a shear or oxygen regime to direct stem cell differentiation. In this way the efficacy of in vitro culture and differentiation of MSCs on three-dimensional scaffolds could be greatly increased. GENERAL SIGNIFICANCE Bioreactor systems have the ability to control many key differentiation stimuli including mechanical stress and oxygen content. The further integration of cell signaling investigations within dynamic culture systems will lead to a quicker realization of the promise of tissue engineering and regenerative medicine. This article is part of a Special Issue entitled Biochemistry of Stem Cells.
Collapse
Affiliation(s)
- Andrew B Yeatts
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA
| | | | | |
Collapse
|
16
|
Goh F, Sambanis A. In vivo noninvasive monitoring of dissolved oxygen concentration within an implanted tissue-engineered pancreatic construct. Tissue Eng Part C Methods 2011; 17:887-94. [PMID: 21486202 DOI: 10.1089/ten.tec.2011.0098] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The function of an implanted tissue-engineered pancreatic construct is influenced by many in vivo factors; however, assessing its function is based primarily on end physiologic effects. As oxygen significantly affects cell function, we established a dual perfluorocarbon method that utilizes (19)F nuclear magnetic resonance spectroscopy, with perfluorocarbons as oxygen concentration markers, to noninvasively monitor dissolved oxygen concentration (DO) in βTC-tet cell-containing alginate beads and at the implantation milieu. Beads were implanted in the peritoneal cavity of normal and streptozotocin-induced diabetic mice. Using this method, the feasibility of acquiring real-time in vivo DO measurements was demonstrated. Results showed that the mouse peritoneal environment is hypoxic and the DO is further reduced when βTC-tet cell constructs were implanted. The DO within cell-containing beads decreased considerably over time and could be correlated with the relative changes in the number of viable encapsulated cells. The reduction of construct DO due to the metabolic activity of the βTC-tet cells was also compatible with the implant therapeutic function, as observed in the reversal of hyperglycemia in diabetic mice. The importance of these findings in assessing implant functionality and host animal physiology is discussed.
Collapse
Affiliation(s)
- Fernie Goh
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | | |
Collapse
|