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Kesserwan S, Sadagurski M, Mao L, Klueh U. Mast Cell Deficiency in Mice Attenuates Insulin Phenolic Preservative-Induced Inflammation. Biomedicines 2023; 11:2258. [PMID: 37626754 PMCID: PMC10452641 DOI: 10.3390/biomedicines11082258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 08/04/2023] [Accepted: 08/08/2023] [Indexed: 08/27/2023] Open
Abstract
One major obstacle that limits the lifespan of insulin infusion pumps is surmounting the tissue site reaction at the device implantation site. All commercial insulin formulations contain insulin phenolic preservatives (IPPs) designed to ensure insulin protein stability and prolong shelf-life. However, our laboratory demonstrated that these preservatives are cytotoxic and induce inflammation. Mature mast cells (MCs) reside in cutaneous tissue and are one of the first responders to an epidermal breach. Upon activation, MCs release proinflammatory and immunomodulatory prepacked mediators that exacerbate these inflammatory reactions. Thus, we hypothesized that once the epidermis is breached, cutaneous MCs are triggered inciting the inflammatory response to IPP-induced inflammation. This hypothesis was pursued utilizing our modified in vivo mouse air pouch model, including a c-kit dependent (C57BL/6J-kitW-sh/W-sh) and a c-kit independent (Cpa3-Cre; Mcl-1fl/fl) MC-deficient mouse model. Leukocytes were quantified in the mouse air pouch lavage fluid following flow cytometry analysis for IPP infusion under three different states, insulin-containing phenolic preservatives (Humalog®), insulin preservatives alone, and normal saline as a control. The air pouch wall was assessed using histopathological evaluations. Flow cytometry analysis demonstrated a statistically significant difference in inflammatory cell recruitment for both MC-deficient mouse models when compared to the control strain including infused control saline. Significantly less inflammation was observed at the site of infusion for the MC-deficient strains compared to the control strain. Overall, concordant results were obtained in both mouse types, C57Bl6-kitW-sh/W-sh and Cpa3-Cre; Mcl-1fl/fl. These findings in multiple model systems support the conclusion that MCs have important or possible unique roles in IPP-induced inflammation.
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Affiliation(s)
| | | | | | - Ulrike Klueh
- Integrative Biosciences Center (IBio), Wayne State University, Detroit, MI 48202, USA; (S.K.); (M.S.)
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2
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de Almeida SA, Orellano LAA, Pereira LX, Viana CTR, Andrade SP, Campos PP, Ferreira MAND. The intensity of the foreign body response to polyether-polyurethane implant in diabetic mice is strain-dependent. Int J Exp Pathol 2021; 102:182-191. [PMID: 34747080 PMCID: PMC8576635 DOI: 10.1111/iep.12397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 03/12/2021] [Accepted: 03/18/2021] [Indexed: 11/27/2022] Open
Abstract
A number of genetic factors have been linked to the development of diabetes, a condition that often requires implantable devices such as glucose sensors. In normoglycaemic individuals, this procedure induces a foreign body reaction (FBR) that is detrimental to bioimplant functionality. However, the influence of the genetic background on this reaction in diabetes has not been investigated. We examined the components of FBR (capsule thickness, collagen deposition, mast cell and foreign body giant cell number) in subcutaneous implants of polyether polyurethane (SIPP) in streptozotocin (STZ)-induced diabetes in Swiss, C57BL/6 and Balb/c mice. The fasting blood glucose levels before STZ injections were 133.5 ± 5.1 mg/dL, after the treatment increased 68.4% in Swiss mice, 62.4% in C57BL/6 and 30.9% in Balb/c mice. All FBR features were higher in implants of Swiss and C57BL/6 mice compared with those in implants of Balb/c. Likewise, the apoptotic index was higher in implants of diabetic Swiss and C57BL/6 mice whose glycaemic levels were the highest. Our findings show an association between the severity of hyperglycaemic levels and the intensity of the FBR to SIPP. These important strain-related differences in susceptibility to diabetes and the intensity of the FBR must be considered in management using implantable devices in diabetic individuals.
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Affiliation(s)
- Simone A. de Almeida
- Departamento de Patologia GeralInstituto de Ciências BiológicasUniversidade Federal de Minas GeraisBelo HorizonteBrazil
| | - Laura A. A. Orellano
- Departamento de Patologia GeralInstituto de Ciências BiológicasUniversidade Federal de Minas GeraisBelo HorizonteBrazil
- Present address:
Department of PathologyUniversity of Massachusetts Medical School368 Plantation StWorcesterMAUSA
| | - Luciana X. Pereira
- Departamento de EnfermagemUniversidade Federal de Alagoas Av. Manoel Severino Barbosa Bom Sucesso – Campus ArapiracaArapiracaBrazil
| | - Celso T. R. Viana
- Departamento de Patologia GeralInstituto de Ciências BiológicasUniversidade Federal de Minas GeraisBelo HorizonteBrazil
| | - Silvia P. Andrade
- Departamento de Fisiologia e BiofisicaUniversidade Federal de Minas GeraisInstituto de Ciências BiológicasBelo HorizonteBrazil
| | - Paula P. Campos
- Departamento de Patologia GeralInstituto de Ciências BiológicasUniversidade Federal de Minas GeraisBelo HorizonteBrazil
| | - Mônica A. N. D. Ferreira
- Departamento de Patologia GeralInstituto de Ciências BiológicasUniversidade Federal de Minas GeraisBelo HorizonteBrazil
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3
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Didyuk O, Econom N, Guardia A, Livingston K, Klueh U. Continuous Glucose Monitoring Devices: Past, Present, and Future Focus on the History and Evolution of Technological Innovation. J Diabetes Sci Technol 2021; 15:676-683. [PMID: 31931614 PMCID: PMC8120065 DOI: 10.1177/1932296819899394] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The concept of implantable glucose sensors has been promulgated for more than 40 years. It is now accepted that continuous glucose monitoring (CGM) increases quality of life by allowing informed diabetes management decisions as a result of more optimized glucose control. The focus of this article is to provide a brief overview of the CGM market history, emerging technologies, and the foreseeable challenges for the next CGM generations as well as proposing possible solutions in an effort to advance the next generation of implantable sensor.
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Affiliation(s)
- Olesya Didyuk
- Department of Biological Sciences, IBio
(Integrative Biosciences Center), Wayne State University, Detroit, MI, USA
| | - Nicolas Econom
- Biomedical Engineering, IBio
(Integrative Biosciences Center), Wayne State University, Detroit, MI, USA
| | - Angelica Guardia
- Biomedical Engineering, IBio
(Integrative Biosciences Center), Wayne State University, Detroit, MI, USA
| | - Kelsey Livingston
- Biomedical Engineering, IBio
(Integrative Biosciences Center), Wayne State University, Detroit, MI, USA
| | - Ulrike Klueh
- Biomedical Engineering, IBio
(Integrative Biosciences Center), Wayne State University, Detroit, MI, USA
- Ulrike Klueh, PhD, Department of Biomedical
Engineering, Wayne State University, 263 Farmington Avenue, Detroit, MI 48202,
USA.
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4
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Mulka A, Lewis BE, Mao L, Sharafieh R, Kesserwan S, Wu R, Kreutzer DL, Klueh U. Phenolic Preservative Removal from Commercial Insulin Formulations Reduces Tissue Inflammation while Maintaining Euglycemia. ACS Pharmacol Transl Sci 2021; 4:1161-1174. [PMID: 34151206 DOI: 10.1021/acsptsci.1c00047] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Indexed: 11/28/2022]
Abstract
Background: Exogenous insulin therapy requires stabilization of the insulin molecule, which is achieved through the use of excipients (e.g., phenolic preservatives (PP)) that provide protein stability, sterility and prolong insulin shelf life. However, our laboratory recently reported that PP, (e.g., m-creosol and phenol) are also cytotoxic, inducing inflammation and fibrosis. Optimizing PP levels through filtration would balance the need for insulin preservation with PP-induced inflammation. Method: Zeolite Y (Z-Y), a size-exclusion-based resin, was employed to remove PP from commercial insulin formulations (Humalog) before infusion. Results: PP removal significantly decreased cell toxicity in vitro and inflammation in vivo. Infusion site histological analysis after a 3 day study demonstrated that leukocyte accumulation increased with nonfiltered preparations but decreased after filtration. Additional studies demonstrated that a Z-Y fabricated filter effectively removed excess PP such that the filtered insulin solution achieved equivalent glycemic control in diabetic mice when compared to nonfiltered insulin. Conclusion: This approach represents the proof of concept that using Z-Y for in-line PP removal assists in lowering inflammation at the site of insulin infusion and thus could lead to extending the functional lifespan of insulin infusion sets in vivo.
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Affiliation(s)
- Adam Mulka
- Department of Biomedical Engineering, Integrative Biosciences Center, Wayne State University, Detroit, Michigan 48202,United States
| | - Brianne E Lewis
- Department of Biomedical Engineering, Integrative Biosciences Center, Wayne State University, Detroit, Michigan 48202,United States
| | - Li Mao
- Department of Biomedical Engineering, Integrative Biosciences Center, Wayne State University, Detroit, Michigan 48202,United States
| | - Roshanak Sharafieh
- Department of Surgery, School of Medicine, University of Connecticut, Farmington, Connecticut 06030-2100, United States
| | - Shereen Kesserwan
- Department of Biomedical Engineering, Integrative Biosciences Center, Wayne State University, Detroit, Michigan 48202,United States
| | - Rong Wu
- Connecticut Convergence Institute, School of Medicine, University of Connecticut, Farmington, Connecticut 06030-6022, United States
| | - Donald L Kreutzer
- Department of Surgery, School of Medicine, University of Connecticut, Farmington, Connecticut 06030-2100, United States
| | - Ulrike Klueh
- Department of Biomedical Engineering, Integrative Biosciences Center, Wayne State University, Detroit, Michigan 48202,United States
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5
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Kesserwan S, Mulka A, Sharafieh R, Qiao Y, Wu R, Kreutzer DL, Klueh U. Advancing continuous subcutaneous insulin infusion in vivo: New insights into tissue challenges. J Biomed Mater Res A 2020; 109:1065-1079. [PMID: 32896081 DOI: 10.1002/jbm.a.37097] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 09/02/2020] [Accepted: 09/03/2020] [Indexed: 01/13/2023]
Abstract
Continuous Subcutaneous Insulin Infusion (CSII) is superior to conventional insulin therapy as it improves glycemic control thus reducing the probability of diabetic complications. Notwithstanding CSII's benefits, insulin dependent diabetic patients rarely achieve optimal glucose control. Moreover, CSII is only FDA approved for 3 days and often fails prematurely for reasons that have not been fully elucidated. We hypothesize that phenolic compounds, such as m-cresol and phenol, which are present in all commercial insulin formulations are responsible for the tissue reaction occurring at the insulin infusion site. This hypothesis was examined with in vitro cell cultures and a mouse air-pouch model to determine cellular and tissue reactions following infusions with saline, phenolic compounds, (i.e., commercial diluent), and insulin. We demonstrated that diluent and insulin were cytotoxic to cells in culture at sub-clinical concentrations (e.g., >1:10 of commercial insulin). Air pouch studies demonstrated that infusion of either diluted insulin or diluent itself induced three to five-fold level of recruited leukocytes as compared to saline. At both 3- and 7-days post infusion, these were predominantly neutrophils and macrophages. We conclude that phenolic compounds in commercial insulin preparations are cell and tissue toxic, which contributes to the failure of effective insulin infusion therapy.
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Affiliation(s)
- Shereen Kesserwan
- Integrative Biosciences Center (IBio), Department of Biomedical Engineering, Wayne State University, Detroit, Michigan, USA
| | - Adam Mulka
- Integrative Biosciences Center (IBio), Department of Biomedical Engineering, Wayne State University, Detroit, Michigan, USA
| | - Roshanak Sharafieh
- Department of Surgery, UConn Health, School of Medicine, Farmington, Connecticut, USA
| | - Yi Qiao
- Department of Surgery, UConn Health, School of Medicine, Farmington, Connecticut, USA
| | - Rong Wu
- Connecticut Convergence Institute for Translation in Regenerative Engineering, UConn Health, Farmington, Connecticut, USA
| | - Donald L Kreutzer
- Department of Surgery, UConn Health, School of Medicine, Farmington, Connecticut, USA
| | - Ulrike Klueh
- Integrative Biosciences Center (IBio), Department of Biomedical Engineering, Wayne State University, Detroit, Michigan, USA.,Department of Surgery, UConn Health, School of Medicine, Farmington, Connecticut, USA
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6
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de Lazari MGT, Pereira LX, Orellano LAA, Scheuermann K, Machado CT, Vasconcelos AC, Andrade SP, Campos PP. Sodium Butyrate Downregulates Implant-Induced Inflammation in Mice. Inflammation 2020; 43:1259-1268. [DOI: 10.1007/s10753-020-01205-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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7
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Carcinogenesis: the cancer cell–mast cell connection. Inflamm Res 2018; 68:103-116. [DOI: 10.1007/s00011-018-1201-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 11/14/2018] [Accepted: 11/14/2018] [Indexed: 12/20/2022] Open
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9
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Reduction of measurement noise in a continuous glucose monitor by coating the sensor with a zwitterionic polymer. Nat Biomed Eng 2018; 2:894-906. [PMID: 30931173 PMCID: PMC6436621 DOI: 10.1038/s41551-018-0273-3] [Citation(s) in RCA: 97] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Continuous glucose monitors (CGMs), used by patients with diabetes mellitus, can autonomously track fluctuations in blood glucose over time. However, the signal produced by CGMs during the initial recording period following sensor implantation contains substantial noise, requiring frequent recalibration via fingerprick tests. Here, we show that coating the sensor with a zwitterionic polymer, found via a combinatorial-chemistry approach, significantly reduces signal noise and improves CGM performance. We evaluated the polymer-coated sensors in mice as well as in healthy and diabetic non-human primates, and show that the sensors accurately record glucose levels without the need for recalibration. We also show that the polymer-coated sensors significantly abrogated immune responses to the sensor, as indicated by histology, fluorescent whole-body imaging of inflammation-associated protease activity, and gene expression of inflammation markers. The polymer coating may allow CGMs to become standalone measuring devices.
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10
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Ajjan RA, Cummings MH, Jennings P, Leelarathna L, Rayman G, Wilmot EG. Accuracy of flash glucose monitoring and continuous glucose monitoring technologies: Implications for clinical practice. Diab Vasc Dis Res 2018; 15:175-184. [PMID: 29446646 DOI: 10.1177/1479164118756240] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Continuous glucose monitoring and flash glucose monitoring technologies measure glucose in the interstitial fluid and are increasingly used in diabetes care. Their accuracy, key to effective glycaemic management, is usually measured using the mean absolute relative difference of the interstitial fluid sensor compared to reference blood glucose readings. However, mean absolute relative difference is not standardised and has limitations. This review aims to provide a consensus opinion on assessing accuracy of interstitial fluid glucose sensing technologies. Mean absolute relative difference is influenced by glucose distribution and rate of change; hence, we express caution on the reliability of comparing mean absolute relative difference data from different study systems and conditions. We also review the pitfalls associated with mean absolute relative difference at different glucose levels and explore additional ways of assessing accuracy of interstitial fluid devices. Importantly, much data indicate that current practice of assessing accuracy of different systems based on individualised mean absolute relative difference results has limitations, which have potential clinical implications. Healthcare professionals must understand the factors that influence mean absolute relative difference as a metric for accuracy and look at additional assessments, such as consensus error grid analysis, when evaluating continuous glucose monitoring and flash glucose monitoring systems in diabetes care. This in turn will ensure that management decisions based on interstitial fluid sensor data are both effective and safe.
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Affiliation(s)
- Ramzi A Ajjan
- 1 St. James's University Hospital, Leeds Teaching Hospitals NHS Trust and LIGHT Laboratories, University of Leeds, Leeds, UK
| | - Michael H Cummings
- 2 Academic Department of Diabetes & Endocrinology, Queen Alexandra Hospital, Portsmouth, UK
| | | | - Lalantha Leelarathna
- 4 Manchester Diabetes Centre, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK
- 5 Division of Diabetes, Endocrinology and Gastroenterology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Gerry Rayman
- 6 The Diabetes Centre, Ipswich Hospital NHS Trust, Ipswich, UK
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11
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Rigla M, Pons B, Rebasa P, Luna A, Pozo FJ, Caixàs A, Villaplana M, Subías D, Bella MR, Combalia N. Human Subcutaneous Tissue Response to Glucose Sensors: Macrophages Accumulation Impact on Sensor Accuracy. Diabetes Technol Ther 2018; 20:296-302. [PMID: 29470128 DOI: 10.1089/dia.2017.0321] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND Subcutaneous (s.c.) glucose sensors have become a key component in type 1 diabetes management. However, their usability is limited by the impact of foreign body response (FBR) on their duration, reliability, and accuracy. Our study gives the first description of human acute and subacute s.c. response to glucose sensors, showing the changes observed in the sensor surface, the inflammatory cells involved in the FBR and their relationship with sensor performance. METHODS Twelve obese patients (seven type 2 diabetes) underwent two abdominal biopsies comprising the surrounding area where they had worn two glucose sensors: the first one inserted 7 days before and the second one 24 h before biopsy procedure. Samples were processed and studied to describe tissue changes by two independent pathologists (blind regarding sensor duration). Macrophages quantification was studied by immunohistochemistry methods in the area surrounding the sensor (CD68, CD163). Sensor surface changes were studied by scanning electron microscopy. Seven-day continuous glucose monitoring records were considered inaccurate when mean absolute relative difference was higher than 10%. RESULTS Pathologists were able to correctly classify all the biopsies regarding sensor duration. Acute response (24 h) was characterized by the presence of neutrophils while macrophages were the main cell involved in subacute inflammation. The number of macrophages around the insertion hole was higher for less accurate sensors compared with those performing more accurately (32.6 ± 14 vs. 10.6 ± 1 cells/0.01 mm2; P < 0.05). CONCLUSION The accumulation of macrophages at the sensor-tissue interface is related with decrease in accuracy of the glucose measure.
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Affiliation(s)
- Mercedes Rigla
- 1 Endocrinology Department, Parc Taulí Sabadell University Hospital, Institut d'Investigacio i Innovació Parc Taulí, Autonomous University of Barcelona , Barcelona, Spain
| | - Belén Pons
- 1 Endocrinology Department, Parc Taulí Sabadell University Hospital, Institut d'Investigacio i Innovació Parc Taulí, Autonomous University of Barcelona , Barcelona, Spain
| | - Pere Rebasa
- 2 General Surgery Department, Parc Taulí Sabadell University Hospital, Institut d'Investigacio i Innovació Parc Taulí, Autonomous University of Barcelona , Barcelona, Spain
| | - Alexis Luna
- 2 General Surgery Department, Parc Taulí Sabadell University Hospital, Institut d'Investigacio i Innovació Parc Taulí, Autonomous University of Barcelona , Barcelona, Spain
| | - Francisco Javier Pozo
- 3 Pathology Department, Parc Taulí Sabadell University Hospital, Institut d'Investigacio i Innovació Parc Taulí, Autonomous University of Barcelona , Barcelona, Spain
| | - Assumpta Caixàs
- 1 Endocrinology Department, Parc Taulí Sabadell University Hospital, Institut d'Investigacio i Innovació Parc Taulí, Autonomous University of Barcelona , Barcelona, Spain
| | - Maria Villaplana
- 1 Endocrinology Department, Parc Taulí Sabadell University Hospital, Institut d'Investigacio i Innovació Parc Taulí, Autonomous University of Barcelona , Barcelona, Spain
| | - David Subías
- 1 Endocrinology Department, Parc Taulí Sabadell University Hospital, Institut d'Investigacio i Innovació Parc Taulí, Autonomous University of Barcelona , Barcelona, Spain
| | - Maria Rosa Bella
- 3 Pathology Department, Parc Taulí Sabadell University Hospital, Institut d'Investigacio i Innovació Parc Taulí, Autonomous University of Barcelona , Barcelona, Spain
| | - Neus Combalia
- 3 Pathology Department, Parc Taulí Sabadell University Hospital, Institut d'Investigacio i Innovació Parc Taulí, Autonomous University of Barcelona , Barcelona, Spain
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12
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Orellano LAA, de Almeida SA, Pereira LX, Couto LC, de Lazari MGT, Viana CTR, Andrade SP, Campos PP. Upregulation of Foreign Body Response in Obese Mice. Obesity (Silver Spring) 2018; 26:531-539. [PMID: 29377630 DOI: 10.1002/oby.22102] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 11/14/2017] [Accepted: 11/27/2017] [Indexed: 11/09/2022]
Abstract
OBJECTIVE Obesity is a highly prevalent multifactorial metabolic condition in which the need for functional bioengineered substitutes (e.g., scaffolds for tissue engineering) is likely to occur. However, the adverse foreign body response (FBR) that invariably takes place adjacent to implant devices impairing their function is poorly characterized in this condition. This study investigated the influence of obesity on the host response to a synthetic matrix implanted subcutaneously in high-fat-fed obese mice. METHODS Histological analysis of 14-day-old implants was performed to identify collagen deposition, capsule thickness, fibroblast-like cells, foreign body giant cells, and mast cells. In addition, transforming growth factor β1 (TGF-β1) levels in the implants and serum were determined. RESULTS All fibrogenic markers (and TGF-β1 levels) increased in the implants of obese mice compared with their nonobese counterparts. Particularly relevant was the fibrous capsule thickness in implants of obese mice (234.2 ± 22.1 µm vs. 109.2 ± 13.4 µm in implants of nonobese animals). CONCLUSIONS The study results showing that obesity upregulates the main features of the FBR induced by subcutaneous implants in mice may be relevant in understanding biomaterial integration and performance in this condition. This is crucial to the development of strategies to maintain the integrity and function of implantable devices.
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Affiliation(s)
- Laura Alejandra Ariza Orellano
- Department of General Pathology, Federal University of Minas Gerais, Institute of Biological Sciences, Belo Horizonte, Minas Gerais, Brazil
| | - Simone Aparecida de Almeida
- Department of General Pathology, Federal University of Minas Gerais, Institute of Biological Sciences, Belo Horizonte, Minas Gerais, Brazil
| | - Luciana Xavier Pereira
- Department of General Pathology, Federal University of Minas Gerais, Institute of Biological Sciences, Belo Horizonte, Minas Gerais, Brazil
| | - Letícia Chinait Couto
- Department of General Pathology, Federal University of Minas Gerais, Institute of Biological Sciences, Belo Horizonte, Minas Gerais, Brazil
| | | | - Celso Tarso Rodrigues Viana
- Department of General Pathology, Federal University of Minas Gerais, Institute of Biological Sciences, Belo Horizonte, Minas Gerais, Brazil
| | - Silvia Passos Andrade
- Department of Physiology and Biophysics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Paula Peixoto Campos
- Department of General Pathology, Federal University of Minas Gerais, Institute of Biological Sciences, Belo Horizonte, Minas Gerais, Brazil
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13
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Soto RJ, Hall JR, Brown MD, Taylor JB, Schoenfisch MH. In Vivo Chemical Sensors: Role of Biocompatibility on Performance and Utility. Anal Chem 2017; 89:276-299. [PMID: 28105839 PMCID: PMC6773264 DOI: 10.1021/acs.analchem.6b04251] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Robert J. Soto
- Department of Chemistry, University of North Carolina at Chapel Hill, CB 3290, Chapel Hill, NC 27599
| | - Jackson R. Hall
- Department of Chemistry, University of North Carolina at Chapel Hill, CB 3290, Chapel Hill, NC 27599
| | - Micah D. Brown
- Department of Chemistry, University of North Carolina at Chapel Hill, CB 3290, Chapel Hill, NC 27599
| | - James B. Taylor
- Department of Chemistry, University of North Carolina at Chapel Hill, CB 3290, Chapel Hill, NC 27599
| | - Mark H. Schoenfisch
- Department of Chemistry, University of North Carolina at Chapel Hill, CB 3290, Chapel Hill, NC 27599
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14
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Klueh U, Czajkowski C, Ludzinska I, Qiao Y, Frailey J, Kreutzer DL. Impact of CCL2 and CCR2 chemokine/receptor deficiencies on macrophage recruitment and continuous glucose monitoring in vivo. Biosens Bioelectron 2016; 86:262-269. [PMID: 27376197 DOI: 10.1016/j.bios.2016.06.026] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 05/26/2016] [Accepted: 06/10/2016] [Indexed: 01/11/2023]
Abstract
The accumulation of macrophages (MΦ) at the sensor-tissue interface is thought to be a major player in controlling tissue reactions and sensor performance in vivo. Nevertheless until recently no direct demonstration of the causal relationship between MΦ aggregation and loss of sensor function existed. Using a Continuous Glucose Monitoring (CGM) murine model we previously demonstrated that genetic deficiencies of MΦ or depletion of MΦ decreased MΦ accumulation at sensor implantation sites, which led to significantly enhanced CGM performance, when compared to normal mice. Additional studies in our laboratories have also demonstrated that MΦ can act as "metabolic sinks" by depleting glucose levels at the implanted sensors in vitro and in vivo. In the present study we extended these observations by demonstrating that MΦ chemokine (CCL2) and receptor (CCR2) knockout mice displayed a decrease in inflammation and MΦ recruitment at sensor implantation sites, when compared to normal mice. This decreased MΦ recruitment significantly enhanced CGM performance when compared to control mice. These studies demonstrated the importance of the CCL2 family of chemokines and related receptors in MΦ recruitment and sensor performance and suggest chemokine targets for enhancing CGM in vivo.
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Affiliation(s)
- Ulrike Klueh
- Center for Molecular Tissue Engineering, University of Connecticut, School of Medicine, Farmington, CT 06030, USA; Department of Surgery, University of Connecticut, School of Medicine, Farmington, CT 06030, USA.
| | - Caroline Czajkowski
- Center for Molecular Tissue Engineering, University of Connecticut, School of Medicine, Farmington, CT 06030, USA; Department of Surgery, University of Connecticut, School of Medicine, Farmington, CT 06030, USA
| | - Izabela Ludzinska
- Center for Molecular Tissue Engineering, University of Connecticut, School of Medicine, Farmington, CT 06030, USA; Department of Surgery, University of Connecticut, School of Medicine, Farmington, CT 06030, USA
| | - Yi Qiao
- Center for Molecular Tissue Engineering, University of Connecticut, School of Medicine, Farmington, CT 06030, USA; Department of Surgery, University of Connecticut, School of Medicine, Farmington, CT 06030, USA
| | - Jackman Frailey
- Center for Molecular Tissue Engineering, University of Connecticut, School of Medicine, Farmington, CT 06030, USA; Department of Surgery, University of Connecticut, School of Medicine, Farmington, CT 06030, USA
| | - Donald L Kreutzer
- Center for Molecular Tissue Engineering, University of Connecticut, School of Medicine, Farmington, CT 06030, USA; Department of Surgery, University of Connecticut, School of Medicine, Farmington, CT 06030, USA
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15
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Bachhuka A, Hayball J, Smith LE, Vasilev K. Effect of Surface Chemical Functionalities on Collagen Deposition by Primary Human Dermal Fibroblasts. ACS APPLIED MATERIALS & INTERFACES 2015; 7:23767-23775. [PMID: 26457649 DOI: 10.1021/acsami.5b08249] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Surface modification has been identified as an important technique that could improve the response of the body to implanted medical devices. Collagen production by fibroblasts is known to play a vital role in wound healing and device fibrous encapsulation. However, how surface chemistry affects collagen I and III deposition by these cells has not been systematically studied. Here, we report how surface chemistry influences the deposition of collagen I and III by primary human dermal fibroblasts. Amine (NH3), carboxyl acid (COOH), and hydrocarbon (CH3) surfaces were generated by plasma deposition. This is a practically relevant tool to deposit a functional coating on any type of substrate material. We show that fibroblasts adhere better and proliferate faster on amine-rich surfaces. In addition, the initial collagen I and III production is greater on this type of coating. These data indicates that surface modification can be a promising route for modulating the rate and level of fibrous encapsulation and may be useful in informing the design of implantable biomedical devices to produce more predictable clinical outcomes.
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Affiliation(s)
| | - John Hayball
- Experimental Therapeutics Laboratory, Sansom Institute and Hanson Institute, School of Pharmacy and Medical Science, University of South Australia , Adelaide, South Australia 5000, Australia
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Avula M, Jones D, Rao AN, McClain D, McGill LD, Grainger DW, Solzbacher F. Local release of masitinib alters in vivo implantable continuous glucose sensor performance. Biosens Bioelectron 2015; 77:149-56. [PMID: 26402593 DOI: 10.1016/j.bios.2015.08.059] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2015] [Revised: 08/24/2015] [Accepted: 08/25/2015] [Indexed: 11/25/2022]
Abstract
Continuous glucose monitoring (CGM) sensors are often advocated as a clinical solution to improve long-term glycemic control in the context of diabetes. Subcutaneous sensor inflammatory response, fouling and fibrous encapsulation resulting from the host foreign body response (FBR) reduce sensor sensitivity to glucose, eventually resulting in sensor performance compromise and device failure. Several combination device strategies load CGM sensors with drug payloads that release locally to tissue sites to mitigate FBR-mediated sensor failure. In this study, the mast cell-targeting tyrosine kinase inhibitor, masitinib, was released from degradable polymer microspheres delivered from the surfaces of FDA-approved human commercial CGM needle-type implanted sensors in a rodent subcutaneous test bed. By targeting the mast cell c-Kit receptor and inhibiting mast cell activation and degranulation, local masitinib penetration around the CGM to several hundred microns sought to reduce sensor fibrosis to extend CGM functional lifetimes in subcutaneous sites. Drug-releasing and control CGM implants were compared in murine percutaneous implant sites for 21 days using direct-wire continuous glucose reporting. Drug-releasing implants exhibited no significant difference in CGM fibrosis at implant sites but showed relatively stable continuous sensor responses over the study period compared to blank microsphere control CGM implants.
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Affiliation(s)
- M Avula
- Department of Bioengineering, University of Utah, Salt Lake City, UT 84112, USA
| | - D Jones
- Department of Internal Medicine, University of Utah, Salt Lake City, UT 84112, USA
| | - A N Rao
- Department of Pharmaceutics and Pharmaceutical Chemistry, University of Utah, Salt Lake City, UT 84112, USA
| | - D McClain
- Department of Internal Medicine, University of Utah, Salt Lake City, UT 84112, USA
| | - L D McGill
- Associated Regional and University Pathologist Laboratories, University of Utah, Salt Lake City, UT 84112, USA
| | - D W Grainger
- Department of Bioengineering, University of Utah, Salt Lake City, UT 84112, USA; Department of Pharmaceutics and Pharmaceutical Chemistry, University of Utah, Salt Lake City, UT 84112, USA.
| | - F Solzbacher
- Department of Bioengineering, University of Utah, Salt Lake City, UT 84112, USA; Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, UT 84112, USA
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17
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Brockway R, Tiesma S, Bogie H, White K, Fine M, O'Farrell L, Michael M, Cox A, Coskun T. Fully Implantable Arterial Blood Glucose Device for Metabolic Research Applications in Rats for Two Months. J Diabetes Sci Technol 2015; 9:771-81. [PMID: 26021562 PMCID: PMC4525668 DOI: 10.1177/1932296815586424] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND Chronic continuous glucose monitoring options for animal research have been very limited due to various technical and biological challenges. We provide an evaluation of a novel telemetry device for continuous monitoring of temperature, activity, and plasma glucose levels in the arterial blood of rats for up to 2 months. METHODS In vivo testing in rats including oral glucose tolerance tests (OGTTs) and intraperitoneal glucose tolerance tests (IPGTTs) and ex vivo waterbath testing were performed to evaluate acute and chronic sensor performance. Animal studies were in accordance with the guidelines for the care and use of laboratory animals and approved by the corresponding animal care and use committees (Data Sciences International, Eli Lilly). RESULTS Results demonstrated the ability to record continuous measurements for 75 days or longer. Bench testing demonstrated a high degree of linearity over a range of 20-850 mg/dL with R(2) = .998 for linear fit and .999 for second order fit (n = 8 sensors). Evaluation of 6 rats over 28 days with 52 daily and OGTT test strip measurements each resulted in mean error of 3.8% and mean absolute relative difference of 16.6%. CONCLUSIONS This device provides significant advantages in the quality and quantity of data that can be obtained relative to existing alternatives such as intermittent blood sampling. These devices provide the opportunity to expand the understanding of both glucose metabolism and homeostasis and to work toward improved therapies and cures for diabetes.
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Affiliation(s)
| | - Scott Tiesma
- Data Sciences International, Inc (DSI), Saint Paul, MN, USA
| | - Heather Bogie
- Data Sciences International, Inc (DSI), Saint Paul, MN, USA
| | - Kimberly White
- Data Sciences International, Inc (DSI), Saint Paul, MN, USA
| | - Megan Fine
- Data Sciences International, Inc (DSI), Saint Paul, MN, USA
| | | | | | - Amy Cox
- Lilly Research Laboratories, Indianapolis, IN, USA
| | - Tamer Coskun
- Lilly Research Laboratories, Indianapolis, IN, USA
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18
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Klueh U, Antar O, Qiao Y, Kreutzer DL. Role of vascular networks in extending glucose sensor function: Impact of angiogenesis and lymphangiogenesis on continuous glucose monitoring in vivo. J Biomed Mater Res A 2014; 102:3512-22. [PMID: 24243850 PMCID: PMC4012020 DOI: 10.1002/jbm.a.35031] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Revised: 10/22/2013] [Accepted: 10/31/2013] [Indexed: 01/10/2023]
Abstract
The concept of increased blood vessel (BV) density proximal to glucose sensors implanted in the interstitial tissue increases the accuracy and lifespan of sensors is accepted, despite limited existing experimental data. Interestingly, there is no previous data or even conjecture in the literature on the role of lymphatic vessels (LV) alone, or in combination with BV, in enhancing continuous glucose monitoring (CGM) in vivo. To investigate the impact of inducing vascular networks (BV and LV) at sites of glucose sensor implantation, we utilized adenovirus based local gene therapy of vascular endothelial cell growth factor-A (VEGF-A) to induce vessels at sensor implantation sites. The results of these studies demonstrated that (1) VEGF-A based local gene therapy increases vascular networks (blood vessels and lymphatic vessels) at sites of glucose sensor implantation; and (2) this local increase of vascular networks enhances glucose sensor function in vivo from 7 days to greater than 28 days postsensor implantation. This data provides "proof of concept" for the effective usage of local angiogenic factor (AF) gene therapy in mammalian models in an effort to extend CGM in vivo. It also supports the practice of a variety of viral and nonviral vectors as well as gene products (e.g. anti-inflammatory and anti-fibrosis genes) to engineer "implant friendly tissues" for the usage with implantable glucose sensors as well as other implantable devices.
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Affiliation(s)
- Ulrike Klueh
- Center for Molecular Tissue Engineering, University of Connecticut, School of Medicine, Farmington, Connecticut 06030
- Department of Surgery, University of Connecticut, School of Medicine, Farmington, Connecticut 06030
| | - Omar Antar
- Center for Molecular Tissue Engineering, University of Connecticut, School of Medicine, Farmington, Connecticut 06030
- Department of Surgery, University of Connecticut, School of Medicine, Farmington, Connecticut 06030
| | - Yi Qiao
- Center for Molecular Tissue Engineering, University of Connecticut, School of Medicine, Farmington, Connecticut 06030
- Department of Surgery, University of Connecticut, School of Medicine, Farmington, Connecticut 06030
| | - Donald L. Kreutzer
- Center for Molecular Tissue Engineering, University of Connecticut, School of Medicine, Farmington, Connecticut 06030
- Department of Surgery, University of Connecticut, School of Medicine, Farmington, Connecticut 06030
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19
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Avula MN, Rao AN, McGill LD, Grainger DW, Solzbacher F. Foreign body response to subcutaneous biomaterial implants in a mast cell-deficient Kit(w-Sh) murine model. Acta Biomater 2014; 10:1856-63. [PMID: 24406200 DOI: 10.1016/j.actbio.2013.12.056] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2013] [Revised: 12/11/2013] [Accepted: 12/26/2013] [Indexed: 12/17/2022]
Abstract
Mast cells (MCs)_are recognized for their functional role in wound-healing and allergic and inflammatory responses - host responses that are frequently detrimental to implanted biomaterials if extended beyond acute reactivity. These tissue reactions impact especially on the performance of sensing implants such as continuous glucose monitoring (CGM) devices. Our hypothesis that effective blockade of MC activity around implants could alter the host foreign body response (FBR) and enhance the in vivo lifetime of these implantable devices motivated this study. Stem cell factor and its ligand c-KIT receptor are critically important for MC survival, differentiation and degranulation. Therefore, an MC-deficient sash mouse model was used to assess MC relationships to the in vivo performance of CGM implants. Additionally, local delivery of a tyrosine kinase inhibitor (TKI) that inhibits c-KIT activity was also used to evaluate the role of MCs in modulating the FBR. Model sensor implants comprising polyester fibers coated with a rapidly dissolving polymer coating containing drug-releasing degradable microspheres were implanted subcutaneously in sash mice for various time points, and the FBR was evaluated for chronic inflammation and fibrous capsule formation around the implants. No significant differences were observed in the foreign body capsule formation between control and drug-releasing implant groups in MC-deficient mice. However, fibrous encapsulation was significantly greater around the drug-releasing implants in sash mice compared to drug-releasing implants in wild-type (e.g. MC-competent) mice. These results provide insights into the role of MCs in the FBR, suggesting that MC deficiency provides alternative pathways for host inflammatory responses to implanted biomaterials.
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Affiliation(s)
- M N Avula
- Department of Bioengineering, University of Utah, Salt Lake City, UT 84112, USA
| | - A N Rao
- Department of Pharmaceutics and Pharmaceutical Chemistry, University of Utah, Salt Lake City, UT 84112, USA
| | - L D McGill
- Associated Regional and University Pathologist Laboratories, University of Utah, Salt Lake City, UT 84112, USA
| | - D W Grainger
- Department of Bioengineering, University of Utah, Salt Lake City, UT 84112, USA; Department of Pharmaceutics and Pharmaceutical Chemistry, University of Utah, Salt Lake City, UT 84112, USA.
| | - F Solzbacher
- Department of Bioengineering, University of Utah, Salt Lake City, UT 84112, USA; Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, UT 84112, USA
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20
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Scuffi C. Interstitium versus Blood Equilibrium in Glucose Concentration and its Impact on Subcutaneous Continuous Glucose Monitoring Systems. EUROPEAN ENDOCRINOLOGY 2014; 10:36-42. [PMID: 29872462 PMCID: PMC5983095 DOI: 10.17925/ee.2014.10.01.36] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Accepted: 02/13/2014] [Indexed: 12/18/2022]
Abstract
The relationship between both interstitial and blood glucose remains a debated topic, on which there is still no consensus. The experimental evidence suggests that blood and interstitial fluid glucose levels are correlated by a kinetic equilibrium, which as a consequence has a time and magnitude gradient in glucose concentration between blood and interstitium. Furthermore, this equilibrium can be perturbed by several physiological effects (such as foreign body response, wound-healing effect, etc.), with a consequent reduction of interstitial fluid glucose versus blood glucose correlation. In the present study, the impact of operating in the interstitium on continuous glucose monitoring systems (CGMs) will be discussed in depth, both for the application of CGMs in the management of diabetes and in other critical areas, such as tight glycaemic control in critically ill patients.
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Affiliation(s)
- Cosimo Scuffi
- Scientist, Scientific and Technology Affairs Department, A. Menarini Diagnostics, Florence, Italy
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21
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Klueh U, Antar O, Qiao Y, Kreutzer DL. Role of interleukin-1/interleukin-1 receptor antagonist family of cytokines in long-term continuous glucose monitoring in vivo. J Diabetes Sci Technol 2013; 7:1538-46. [PMID: 24351180 PMCID: PMC3876332 DOI: 10.1177/193229681300700614] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Glucose-sensor-induced tissue reactions (e.g., inflammation and wound healing) are known to negatively impact sensor function in vivo. The roles of cytokine networks in controlling these tissue reactions (i.e., sensor biofouling) is not understood. In the present study, we investigated the role of interleukin-1 receptor antagonist (IL-1Ra), a key anti-inflammatory antagonist of the proinflammatory interleukin-1 cytokines [i.e. interleukin-1 (IL-1) alpha and IL-1 beta] in controlling continuous glucose monitoring (CGM). METHODS To investigate the role of IL-1Ra in long-term CGM in vivo, we compared CGM in transgenic mice that overexpress IL-1Ra [interleukin-1 receptor antagonist overexpresser (IL-1Ra~OE), B6.Cg-Tg(IL1rn)1Dih/J] or are deficient in IL-1Ra [interleukin-1 receptor antagonist knockout (IL-1Ra~KO), B6.129S-IL1rn(tm1Dih)/J] with mice that have normal levels of IL-1Ra (C57BL/6) over a 28-day time period. RESULTS Mean absolute relative difference (MARD) analysis of CGM results among the mice of varying IL-1Ra levels demonstrated that during the first 21 days, IL-1~KO mice had the greatest tissue inflammation and the poorest sensor performance (i.e., higher MARD values) when compared with normal or IL-1Ra~OE mice. By 28 days post-sensor implantation, the inflammatory reactions had subsided and were replaced by varying degrees of fibrosis. CONCLUSIONS These data support our hypothesis on the importance of the IL-1 family of agonists and antagonists in controlling tissue reactions and sensor function in vivo. These data also suggest that local delivery of IL-1Ra genes or recombinant proteins (anakinra) or other IL-1 antagonists such as antibodies or soluble IL-1 receptors would suppress sensor-induced tissue reactions and likely enhance glucose sensor function by inhibiting inflammation and wound healing at sensor implantation sites.
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Affiliation(s)
- Ulrike Klueh
- Center for Molecular Tissue Engineering, University of Connecticut School of Medicine, Farmington, CT.
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22
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Abstract
Continuous glucose monitoring (CGM) is an emerging technology that provides a continuous measure of interstitial glucose levels. In addition to providing a more complete pattern of glucose excursions, CGMs utilize real-time alarms for thresholds and predictions of hypo- and hyperglycemia, as well as rate of change alarms for rapid glycemic excursions. CGM users have been able to improve glycemic control without increasing their risk of hypoglycemia. Sensor accuracy, reliability, and wearability are important challenges to CGM success and are critical to the development of an artificial pancreas (or closed-loop system).
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Affiliation(s)
- Daniel DeSalvo
- Department of Pediatric Endocrinology and Diabetes, Stanford Medical Center, G-313, 300 Pasteur Drive, Stanford, CA, 94305, USA
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23
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Avula MN, Rao AN, McGill LD, Grainger DW, Solzbacher F. Modulation of the foreign body response to implanted sensor models through device-based delivery of the tyrosine kinase inhibitor, masitinib. Biomaterials 2013; 34:9737-46. [PMID: 24060424 DOI: 10.1016/j.biomaterials.2013.08.090] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Accepted: 08/30/2013] [Indexed: 11/30/2022]
Abstract
The host foreign body response (FBR) adversely effects the performance of numerous implanted biomaterials especially biosensors, including clinically popular glucose-monitoring sensors. Reactive formation of a fibrous capsule around implanted sensors hinders the transport of essential analytes to the sensor from the surrounding tissue, resulting in loss of glucose response sensitivity and eventual sensor failure. Several strategies have sought to mitigate the foreign body response's effects on CGM sensors through the use of local delivery of pharmaceuticals and biomolecules with limited success. This study describes release of a tyrosine kinase inhibitor - masitinib - from the sensor implant to target tissue resident mast cells as key mediators of the FBR. Model implants are coated with a composite polymer hydrophilic matrix that rapidly dissolves upon tissue implantation to deposit slower-degrading polymer microparticles containing masitinib. Matrix dissolution limits coating interference with sensor function while establishing a local controlled-release delivery depot formulation to alter implant tissue pharmacology and addressing the FBR. Drug efficacy was evaluated in a murine subcutaneous pocket implant model. Drug release extends to more than 30 days in vitro. The resulting FBR in vivo, evaluated by implant capsule thickness and inflammatory cell densities at 14, 21, and 28 days, displays statistically significant reduction in capsule thickness around masitinib-releasing implant sites compared to control implant sites.
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Affiliation(s)
- Mahender Nath Avula
- Department of Bioengineering, University of Utah, Salt Lake City, UT 84112, USA
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24
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Poljakova I, Elsikova E, Chlup R, Kalabus S, Hasala P, Zapletalova J. Glucose sensing module - is it time to integrate it into real-time perioperative monitoring? An observational pilot study with subcutaneous sensors. Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub 2013; 157:346-57. [PMID: 23887609 DOI: 10.5507/bp.2013.049] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Accepted: 06/17/2013] [Indexed: 11/23/2022] Open
Abstract
AIMS To explore the feasibility of subcutaneous continuous glucose monitoring (CGM) in perioperative settings and to evaluate the perioperative development of glycaemia in persons with diabetes mellitus or impaired glucose tolerance by means of CGM. METHODS Monitoring by means of Guardian REAL-Time CGMS (Medtronic, Nortridge, USA) in 20 perioperative periods. Sensor was inserted on the day before surgery and continued for 3 days with some exceptions. RESULTS Full implementation of the method was successful in the intensive care unit setting only. No electromagnetic interference and no side effects were found. The Wilcoxon signed-rank test revealed no significant difference between sensor and laboratory analyser values. Pearson's correlation coefficients of the values obtained by sensor and the Wellion Linus glucometer were 0.875 for the whole perioperative period, 0.866 for the intraoperative period and 0.903 for the first perioperative day. A decline in sensor accuracy on the 6(th) day was registered in one case. 16 monitored cases (80%) did not meet the criteria for safe plasma glucose range. Hypoglycaemia was found in 4 (20%) cases. There was an association between grade of the perioperative dysglycaemia and need for reoperation within the next 3 months. The most frequent perioperative glycaemic patterns are demonstrated. CONCLUSION Subcutaneous CGM is safe offering detailed insight into glucose homeostasis in the dynamic perioperative period. Laboratory confirmation of sensor plasma glucose concentration by approved laboratory analyser is still necessary. The potentional benefits of maintaining patients within a safe glucose range should be comfirmed by future studies.
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Affiliation(s)
- Iveta Poljakova
- Department of Physiology, Faculty of Medicine and Dentistry, Palacky University Olomouc, Czech Republic
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25
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Nichols SP, Koh A, Storm WL, Shin JH, Schoenfisch MH. Biocompatible materials for continuous glucose monitoring devices. Chem Rev 2013; 113:2528-49. [PMID: 23387395 PMCID: PMC3624030 DOI: 10.1021/cr300387j] [Citation(s) in RCA: 188] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Scott P. Nichols
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Ahyeon Koh
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Wesley L. Storm
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Jae Ho Shin
- Department of Chemistry, Kwangwoon University, Seoul, Korea
| | - Mark H. Schoenfisch
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
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26
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Fathabadie FF, Bayat M, Amini A, Bayat M, Rezaie F. Effects of pulsed infra-red low level-laser irradiation on mast cells number and degranulation in open skin wound healing of healthy and streptozotocin-induced diabetic rats. J COSMET LASER THER 2013; 15:294-304. [DOI: 10.3109/14764172.2013.764435] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Abstract
It is generally accepted that unreliable in vivo performance of implantable glucose sensors originates, in large part, from tissue reactions to the implanted sensor, including foreign body reactions (i.e., inflammation, fibrosis, and vessel regression). Development of glucose sensor coatings with increased biocompatibility would contribute to the development of a reliable long-term glucose sensor. In this issue of Journal of Diabetes Science and Technology, Van den Bosch and coauthors report on their initial in vitro results on a candidate biocompatibility coating for sensors (silica nanoparticle- polyethylene-glycol-based coating). Although the initial standard testing is encouraging, it is important that sensor-specific testing protocol be utilized to more accurately predict sensor performance in vivo. The development and application of sensor-specific testing standards will likely speed the development of biocompatible coatings that will increase sensor accuracy and lifespan in the future.
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Affiliation(s)
- Ulrike Klueh
- Center for Molecular Tissue Engineering, Department of Surgery, University of Connecticut, School of Medicine, Farmington, CT 06030, USA.
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28
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Nichols SP, Koh A, Brown NL, Rose MB, Sun B, Slomberg DL, Riccio DA, Klitzman B, Schoenfisch MH. The effect of nitric oxide surface flux on the foreign body response to subcutaneous implants. Biomaterials 2012; 33:6305-12. [PMID: 22748919 PMCID: PMC3667553 DOI: 10.1016/j.biomaterials.2012.05.053] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Accepted: 05/20/2012] [Indexed: 01/09/2023]
Abstract
Although the release of nitric oxide (NO) from biomaterials has been shown to reduce the foreign body response (FBR), the optimal NO release kinetics and doses remain unknown. Herein, polyurethane-coated wire substrates with varying NO release properties were implanted into porcine subcutaneous tissue for 3, 7, 21 and 42 d. Histological analysis revealed that materials with short NO release durations (i.e., 24 h) were insufficient to reduce the collagen capsule thickness at 3 and 6 weeks, whereas implants with longer release durations (i.e., 3 and 14 d) and greater NO payloads significantly reduced the collagen encapsulation at both 3 and 6 weeks. The acute inflammatory response was mitigated most notably by systems with the longest duration and greatest dose of NO release, supporting the notion that these properties are most critical in circumventing the FBR for subcutaneous biomedical applications (e.g., glucose sensors).
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Affiliation(s)
- Scott P. Nichols
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Ahyeon Koh
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Nga L. Brown
- Kenan Plastic Surgery Research Laboratories, Department of Biomedical Engineering, Duke University Medical Center, Durham, NC 27710, USA
| | - Michael B. Rose
- Kenan Plastic Surgery Research Laboratories, Department of Biomedical Engineering, Duke University Medical Center, Durham, NC 27710, USA
| | - Bin Sun
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Danielle L. Slomberg
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Daniel A. Riccio
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Bruce Klitzman
- Kenan Plastic Surgery Research Laboratories, Department of Biomedical Engineering, Duke University Medical Center, Durham, NC 27710, USA
| | - Mark H. Schoenfisch
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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29
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Sokolov A, Hellerud BC, Lambris JD, Johannessen EA, Mollnes TE. Activation of polymorphonuclear leukocytes by candidate biomaterials for an implantable glucose sensor. J Diabetes Sci Technol 2011; 5:1490-8. [PMID: 22226271 PMCID: PMC3262720 DOI: 10.1177/193229681100500625] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Continuous monitoring of glucose by implantable microfabricated devices offers key advantages over current transcutaneous glucose sensors that limit usability due to their obtrusive nature and risk of infection. A successful sensory implant should be biocompatible and retain long-lasting function. Polymorphonuclear leukocytes (PMN) play a key role in the inflammatory system by releasing enzymes, cytokines, and reactive oxygen species, typically as a response to complement activation. The aim of this study was to perform an in vitro analysis of PMN activation as a marker for biocompatibility of materials and to evaluate the role of complement in the activation of PMN. METHODS Fifteen candidate materials of an implantable glucose sensor were incubated in lepirudin-anticoagulated whole blood. The cluster of differentiation molecule 11b (CD11b) expression on PMN was analyzed with flow cytometry and the myeloperoxidase (MPO) concentration in plasma was analyzed with enzyme-linked immunosorbent assay. Complement activation was prevented by the C3 inhibitor compstatin or the C5 inhibitor eculizumab. RESULTS Three of the biomaterials (cellulose ester, polyamide reverse osmosis membrane, and polyamide thin film membrane), all belonging to the membrane group, induced a substantial and significant increase in CD11b expression and MPO release. The changes were virtually identical for these two markers. Inhibition of complement with compstatin or eculizumab reduced the CD11b expression and MPO release dose dependently and in most cases back to baseline. The other 12 materials did not induce significant PMN activation. CONCLUSION Three of the 15 candidate materials triggered PMN activation in a complement-dependent manner and should therefore be avoided for implementation in implantable microsensors.
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Affiliation(s)
- Andrey Sokolov
- Institute of Immunology, University of Oslo and Oslo University Hospital Rikshospitalet, Oslo, Norway.
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30
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The Amazing Power of Cancer Cells to Recapitulate Extraembryonic Functions: The Cuckoo's Tricks. JOURNAL OF ONCOLOGY 2011; 2012:521284. [PMID: 21969829 PMCID: PMC3182376 DOI: 10.1155/2012/521284] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/14/2011] [Revised: 07/06/2011] [Accepted: 07/07/2011] [Indexed: 12/14/2022]
Abstract
Inflammation is implicated in tumor development, invasion, and metastasis. Hence, it has been suggested that common cellular and molecular mechanisms are activated in wound repair and in cancer development. In addition, it has been previously proposed that the inflammatory response, which is associated with the wound healing process, could recapitulate ontogeny through the reexpression of the extraembryonic, that is, amniotic and vitelline, functions in the interstitial space of the injured tissue. If so, the use of inflammation by the cancer-initiating cell can also be supported in the ability to reacquire extraembryonic functional axes for tumor development, invasion, and metastasis. Thus, the diverse components of the tumor microenvironment could represent the overlapping reexpression of amniotic and vitelline functions. These functions would favor a gastrulation-like process, that is, the creation of a reactive stroma in which fibrogenesis and angiogenesis stand out.
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Abstract
Continuous glucose monitoring devices remain limited in their duration of use due to difficulties presented by the foreign body response (FBR), which impairs sensor functionality immediately following implantation via biofouling and leukocyte infiltration. The FBR persists through the life of the implant, culminating with fibrous encapsulation and isolation from normal tissue. These issues have led researchers to develop strategies to mitigate the FBR and improve tissue integration. Studies have often focused on abating the FBR using various outer coatings, thereby changing the chemical or physical characteristics of the sensor surface. While such strategies have led to some success, they have failed to fully integrate the sensor into surrounding tissue. To further address biocompatibility, researchers have designed coatings capable of actively releasing biological agents (e.g., vascular endothelial growth factor, dexamethasone, and nitric oxide) to direct the FBR to induce tissue integration. Active release approaches have proven promising and, when combined with biocompatible coating materials, may ultimately improve the in vivo lifetime of subcutaneous glucose biosensors. This article focuses on strategies currently under development for mitigating the FBR.
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Affiliation(s)
- Ahyeon Koh
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
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Klueh U, Liu Z, Feldman B, Henning TP, Cho B, Ouyang T, Kreutzer D. Metabolic biofouling of glucose sensors in vivo: role of tissue microhemorrhages. J Diabetes Sci Technol 2011; 5:583-95. [PMID: 21722574 PMCID: PMC3192625 DOI: 10.1177/193229681100500313] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Based on our in vitro study that demonstrated the adverse effects of blood clots on glucose sensor function, we hypothesized that in vivo local tissue hemorrhages, induced as a consequence of sensor implantation or sensor movement post-implantation, are responsible for unreliable readings or an unexplained loss of functionality shortly after implantation. RESEARCH DESIGN AND METHODS To investigate this issue, we utilized real-time continuous monitoring of blood glucose levels in a mouse model. Direct injection of blood at the tissue site of sensor implantation was utilized to mimic sensor-induced local tissue hemorrhages. RESULTS It was found that blood injections, proximal to the sensor, consistently caused lowered sensor glucose readings, designated temporary signal reduction, in vivo in our mouse model, while injections of plasma or saline did not have this effect. CONCLUSION These results support our hypothesis that tissue hemorrhage and resulting blood clots near the sensor can result in lowered local blood glucose concentrations due to metabolism of glucose by the clot. The lowered local blood glucose concentration led to low glucose readings from the still functioning sensor that did not reflect the systemic glucose level.
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Affiliation(s)
- Ulrike Klueh
- Center for Molecular Tissue Engineering, School of Medicine, University of Connecticut, Farmington, Connecticut, USA.
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Helton KL, Ratner BD, Wisniewski NA. Biomechanics of the sensor-tissue interface-effects of motion, pressure, and design on sensor performance and the foreign body response-part I: theoretical framework. J Diabetes Sci Technol 2011; 5:632-46. [PMID: 21722578 PMCID: PMC3192629 DOI: 10.1177/193229681100500317] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The importance of biomechanics in glucose sensor function has been largely overlooked. This article is the first part of a two-part review in which we look beyond commonly recognized chemical biocompatibility to explore the biomechanics of the sensor-tissue interface as an important aspect of continuous glucose sensor biocompatibility. Part I provides a theoretical framework to describe how biomechanical factors such as motion and pressure (typically micromotion and micropressure) give rise to interfacial stresses, which affect tissue physiology around a sensor and, in turn, impact sensor performance. Three main contributors to sensor motion and pressure are explored: applied forces, sensor design, and subject/patient considerations. We describe how acute forces can temporarily impact sensor signal and how chronic forces can alter the foreign body response and inflammation around an implanted sensor, and thus impact sensor performance. The importance of sensor design (e.g., size, shape, modulus, texture) and specific implant location on the tissue response are also explored. In Part II: Examples and Application (a sister publication), examples from the literature are reviewed, and the application of biomechanical concepts to sensor design are described. We believe that adding biomechanical strategies to the arsenal of material compositions, surface modifications, drug elution, and other chemical strategies will lead to improvements in sensor biocompatibility and performance.
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Klueh U, Liu Z, Feldman B, Kreutzer D. Importance of interleukin-1 and interleukin-1 receptor antagonist in short-term glucose sensor function in vivo. J Diabetes Sci Technol 2010; 4:1073-86. [PMID: 20920427 PMCID: PMC2956811 DOI: 10.1177/193229681000400506] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND The importance of the interleukin (IL)-1 cytokine family in inflammation and immunity is well established as a result of extensive in vitro and in vivo studies. In fact, much of our understanding of the in vivo importance of interleukin-1beta (IL-1B) is the result of research utilizing transgenic mice, such as overexpression or deficiencies of the naturally occurring inhibitor of IL-1 known as interleukin-1 receptor antagonist (IL-1RA). For the present studies, we utilized these transgenic mice to determine the role of IL-1B in glucose sensor function in vivo. METHODS To investigate the role of IL-1B in glucose sensor function in vivo, we compared glucose sensor function in trans-genic mice that (1) overexpressed IL-1RA [B6.Cg-Tg(II1rn)1Dih/J] and (2) are deficient in IL-1RA (B6.129S-Il1rn(tm1Dih)/J), with mice that have normal levels of IL-1RA (C57BL/6). RESULTS Our studies demonstrated that, during the first 7 days post-sensor implantation (PSI), mice deficient in IL-1RA had extensive inflammation and decreased sensor function when compared to normal or IL-1RA-overexpressing mice. CONCLUSION These data directly support our hypothesis that the IL-1 family of cytokines and antagonists play a critical role in controlling tissue reactions and thereby sensor function in vivo during the first 7 days PSI.
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Affiliation(s)
- Ulrike Klueh
- Center for Molecular Tissue Engineering, School of Medicine, University of Connecticut, Farmington, Connecticut 06030, USA.
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Ekberg NR, Brismar K, Malmstedt J, Hedblad MA, Adamson U, Ungerstedt U, Wisniewski N. Analyte flux at a biomaterial-tissue interface over time: implications for sensors for type 1 and 2 diabetes mellitus. J Diabetes Sci Technol 2010; 4:1063-72. [PMID: 20920426 PMCID: PMC2956810 DOI: 10.1177/193229681000400505] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE The very presence of an implanted sensor (a foreign body) causes changes in the adjacent tissue that may alter the analytes being sensed. The objective of this study was to investigate changes in glucose availability and local tissue metabolism at the sensor-tissue interface in patients with type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM). METHOD Microdialysis was used to model implanted sensors. Capillary glucose and subcutaneous (sc) microdialysate analytes were monitored in five T1DM and five T2DM patients. Analytes included glucose, glycolysis metabolites (lactate, pyruvate), a lipolysis metabolite (glycerol), and a protein degradation byproduct (urea). On eight consecutive days, four measurements were taken during a period of steady state blood glucose. RESULTS Microdialysate glucose and microdialysate-to-blood-glucose ratio increased over the first several days in all patients. Although glucose recovery eventually stabilized, the lactate levels continued to rise. These trends were explained by local inflammatory and microvascular changes observed in histological analysis of biopsy samples. Urea concentrations mirrored glucose trends. Urea is neither produced nor consumed in sc tissue, and so the initially increasing urea trend is explained by increased local capillary presence during the inflammatory process. Pyruvate in T2DM microdialysate was significantly higher than in T1DM, an observation that is possibly explained by mitochondrial dysfunction in T2DM. Glycerol in T2DM microdialysate (but not in T1DM) was higher than in healthy volunteers, which is likely explained by sc insulin resistance (insulin is a potent antilipolytic hormone). Urea was also higher in microdialysate of patients with diabetes mellitus compared to healthy volunteers. Urea is a byproduct of protein degradation, which is known to be inhibited by insulin. Therefore, insulin deficiency or resistance may explain the higher urea levels. To our knowledge, this is the first histological evaluation of a human tissue biopsy containing an implanted glucose monitoring device. CONCLUSIONS Monitoring metabolic changes at a material-tissue interface combined with biopsy histology helped to formulate an understanding of physiological changes adjacent to implanted glucose sensors. Microdialysate glucose trends were similar over 1-week in T1DM and T2DM; however, differences in other analytes indicated wound healing and metabolic activities in the two patient groups differ. We propose explanations for the specific observed differences based on differential insulin insufficiency/resistance and mitochondrial dysfunction in T1DM versus T2DM.
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Affiliation(s)
- Neda Rajamand Ekberg
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.
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Liao KC, Chang SC, Chiu CY, Chou YH. Acute response in vivo of a fiber-optic sensor for continuous glucose monitoring from canine studies on point accuracy. SENSORS 2010; 10:7789-802. [PMID: 22163627 PMCID: PMC3231153 DOI: 10.3390/s100807789] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2010] [Revised: 07/26/2010] [Accepted: 08/05/2010] [Indexed: 11/16/2022]
Abstract
The objective of this study was to evaluate the acute response of Sencil(™), a fiber-optic sensor, in point accuracy for glucose monitoring in vivo on healthy dogs under anesthesia. A total of four dogs with clinically normal glycemia were implanted with one sensor each in the chest region to measure the interstitial glucose concentration during the ovariohysterectomy procedure. The data was acquired every 10 seconds after initiation, and was compared to the concentration of venous plasma glucose sampled during the surgery procedures for accuracy of agreement analysis. In the four trials with a range of 71-297 mg/dL plasma glucose, the collected 21 pairs of ISF readings from the Sencil™ and the plasma reference showed superior dispersion of residue values than the conventional system, and a linear correlation (the Pearson correlation coefficient is 0.9288 and the y-intercept is 14.22 mg/dL). The MAD (17.6 mg/dL) and RMAD (16.16%) of Sencil™ measurements were in the comparable range of the conventional system. The Clarke error grid analysis indicated that 100% of the paired points were in the clinically acceptable zone A (61.9%) and B (38.1%).
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Affiliation(s)
- Kuo-Chih Liao
- Graduate Institute of Biomedical Engineering, National Chung-Hsing University, 250 Kuo-Kuang Rd., Taichung City, 40227, Taiwan; E-Mail: (Y.-H.C.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +886-4-22840734-28; Fax: +886-4-222852422
| | - Shih-Chieh Chang
- Department of Veterinary Medicine / Veterinary Medical Teaching Hospital, National Chung-Hsing University, 250 Kuo-Kuang Rd., Taichung City, 40227, Taiwan; E-Mails: (S.-C.C.); (C.-Y.C.)
| | - Cheng-Yang Chiu
- Department of Veterinary Medicine / Veterinary Medical Teaching Hospital, National Chung-Hsing University, 250 Kuo-Kuang Rd., Taichung City, 40227, Taiwan; E-Mails: (S.-C.C.); (C.-Y.C.)
| | - Yu-Hsiang Chou
- Graduate Institute of Biomedical Engineering, National Chung-Hsing University, 250 Kuo-Kuang Rd., Taichung City, 40227, Taiwan; E-Mail: (Y.-H.C.)
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