1
|
Swan SL, Mehta N, Ilich E, Shen SH, Wilkinson DS, Anderson AR, Segura T, Sanchez-Perez L, Sampson JH, Bellamkonda RV. IL7 and IL7 Flt3L co-expressing CAR T cells improve therapeutic efficacy in mouse EGFRvIII heterogeneous glioblastoma. Front Immunol 2023; 14:1085547. [PMID: 36817432 PMCID: PMC9936235 DOI: 10.3389/fimmu.2023.1085547] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Accepted: 01/04/2023] [Indexed: 02/05/2023] Open
Abstract
Chimeric antigen receptor (CAR) T cell therapy in glioblastoma faces many challenges including insufficient CAR T cell abundance and antigen-negative tumor cells evading targeting. Unfortunately, preclinical studies evaluating CAR T cells in glioblastoma focus on tumor models that express a single antigen, use immunocompromised animals, and/or pre-treat with lymphodepleting agents. While lymphodepletion enhances CAR T cell efficacy, it diminishes the endogenous immune system that has the potential for tumor eradication. Here, we engineered CAR T cells to express IL7 and/or Flt3L in 50% EGFRvIII-positive and -negative orthotopic tumors pre-conditioned with non-lymphodepleting irradiation. IL7 and IL7 Flt3L CAR T cells increased intratumoral CAR T cell abundance seven days after treatment. IL7 co-expression with Flt3L modestly increased conventional dendritic cells as well as the CD103+XCR1+ population known to have migratory and antigen cross-presenting capabilities. Treatment with IL7 or IL7 Flt3L CAR T cells improved overall survival to 67% and 50%, respectively, compared to 9% survival with conventional or Flt3L CAR T cells. We concluded that CAR T cells modified to express IL7 enhanced CAR T cell abundance and improved overall survival in EGFRvIII heterogeneous tumors pre-conditioned with non-lymphodepleting irradiation. Potentially IL7 or IL7 Flt3L CAR T cells can provide new opportunities to combine CAR T cells with other immunotherapies for the treatment of glioblastoma.
Collapse
Affiliation(s)
- Sheridan L Swan
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
| | - Nalini Mehta
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
| | - Ekaterina Ilich
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
| | - Steven H Shen
- Duke Brain Tumor Immunotherapy Program, Department of Neurosurgery, Duke University Medical Center, Durham, NC, United States.,The Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, NC, United States.,Department of Pathology, Duke University Medical Center, Durham, NC, United States
| | - Daniel S Wilkinson
- Duke Brain Tumor Immunotherapy Program, Department of Neurosurgery, Duke University Medical Center, Durham, NC, United States
| | - Alexa R Anderson
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
| | - Tatiana Segura
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States.,Clinical Science Departments of Neurology and Dermatology, Duke University, Durham, NC, United States
| | - Luis Sanchez-Perez
- Duke Brain Tumor Immunotherapy Program, Department of Neurosurgery, Duke University Medical Center, Durham, NC, United States.,The Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, NC, United States.,Department of Neurosurgery, Duke University Medical Center, Durham, NC, United States
| | - John H Sampson
- Duke Brain Tumor Immunotherapy Program, Department of Neurosurgery, Duke University Medical Center, Durham, NC, United States.,The Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, NC, United States.,Department of Pathology, Duke University Medical Center, Durham, NC, United States.,Department of Neurosurgery, Duke University Medical Center, Durham, NC, United States
| | - Ravi V Bellamkonda
- Department of Biology, Emory University, Atlanta, GA, United States.,Wallace H. Coulter Department of Biomedical Engineering, Emory University, Atlanta, GA, United States
| |
Collapse
|
2
|
Enam SF, Kilic CY, Huang J, Kang BJ, Chen R, Tribble CS, Ilich E, Betancur MI, Blocker SJ, Owen SJ, Buckley AF, Lyon JG, Bellamkonda RV. Cytostatic hypothermia and its impact on glioblastoma and survival. Sci Adv 2022; 8:eabq4882. [PMID: 36427309 PMCID: PMC9699673 DOI: 10.1126/sciadv.abq4882] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Accepted: 10/27/2022] [Indexed: 06/16/2023]
Abstract
Patients with glioblastoma (GBM) have limited options and require novel approaches to treatment. Here, we studied and deployed nonfreezing "cytostatic" hypothermia to stunt GBM growth. This growth-halting method contrasts with ablative, cryogenic hypothermia that kills both neoplastic and infiltrated healthy tissue. We investigated degrees of hypothermia in vitro and identified a cytostatic window of 20° to 25°C. For some lines, 18 hours/day of cytostatic hypothermia was sufficient to halt division in vitro. Next, we fabricated an experimental tool to test local cytostatic hypothermia in two rodent GBM models. Hypothermia more than doubled median survival, and all rats that successfully received cytostatic hypothermia survived their study period. Unlike targeted therapeutics that are successful in preclinical models but fail in clinical trials, cytostatic hypothermia leverages fundamental physics that influences biology broadly. It is a previously unexplored approach that could provide an additional option to patients with GBM by halting tumor growth.
Collapse
Affiliation(s)
- Syed Faaiz Enam
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27705, USA
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX 75235, USA
| | - Cem Y. Kilic
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27705, USA
| | - Jianxi Huang
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27705, USA
| | - Brian J. Kang
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27705, USA
| | - Reed Chen
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27705, USA
| | - Connor S. Tribble
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27705, USA
| | - Ekaterina Ilich
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27705, USA
| | - Martha I. Betancur
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27705, USA
| | - Stephanie J. Blocker
- Department of Radiology, Center for In Vivo Microscopy, Duke University, Durham, NC 27705, USA
| | - Steven J. Owen
- Bio-medical Machine Shop, Pratt School of Engineering, Duke University, Durham, NC 27705, USA
| | - Anne F. Buckley
- Department of Pathology, School of Medicine, Duke University, Durham, NC 27705, USA
| | - Johnathan G. Lyon
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27705, USA
- Department of Biology, Emory University, Atlanta, GA 30332, USA
| | - Ravi V. Bellamkonda
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27705, USA
- Department of Biology, Emory University, Atlanta, GA 30332, USA
| |
Collapse
|
3
|
Motz CT, Kabat V, Saxena T, Bellamkonda RV, Zhu C. Neuromechanobiology: An Expanding Field Driven by the Force of Greater Focus. Adv Healthc Mater 2021; 10:e2100102. [PMID: 34342167 PMCID: PMC8497434 DOI: 10.1002/adhm.202100102] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 07/06/2021] [Indexed: 12/14/2022]
Abstract
The brain processes information by transmitting signals through highly connected and dynamic networks of neurons. Neurons use specific cellular structures, including axons, dendrites and synapses, and specific molecules, including cell adhesion molecules, ion channels and chemical receptors to form, maintain and communicate among cells in the networks. These cellular and molecular processes take place in environments rich of mechanical cues, thus offering ample opportunities for mechanical regulation of neural development and function. Recent studies have suggested the importance of mechanical cues and their potential regulatory roles in the development and maintenance of these neuronal structures. Also suggested are the importance of mechanical cues and their potential regulatory roles in the interaction and function of molecules mediating the interneuronal communications. In this review, the current understanding is integrated and promising future directions of neuromechanobiology are suggested at the cellular and molecular levels. Several neuronal processes where mechanics likely plays a role are examined and how forces affect ligand binding, conformational change, and signal induction of molecules key to these neuronal processes are indicated, especially at the synapse. The disease relevance of neuromechanobiology as well as therapies and engineering solutions to neurological disorders stemmed from this emergent field of study are also discussed.
Collapse
Affiliation(s)
- Cara T Motz
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332-0363, USA
- Parker H. Petit Institute for Bioengineering and Biosciences, Georgia Institute of Technology, Atlanta, GA, 30332-0363, USA
| | - Victoria Kabat
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332-0363, USA
| | - Tarun Saxena
- Department of Biomedical Engineering, Duke University, Durham, NC, 27709, USA
| | - Ravi V Bellamkonda
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, 27708, USA
| | - Cheng Zhu
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332-0363, USA
- Parker H. Petit Institute for Bioengineering and Biosciences, Georgia Institute of Technology, Atlanta, GA, 30332-0363, USA
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332-0363, USA
| |
Collapse
|
4
|
Park E, Lyon JG, Alvarado-Velez M, Betancur MI, Mokarram N, Shin JH, Bellamkonda RV. Enriching neural stem cell and anti-inflammatory glial phenotypes with electrical stimulation after traumatic brain injury in male rats. J Neurosci Res 2021; 99:1864-1884. [PMID: 33772860 PMCID: PMC8360147 DOI: 10.1002/jnr.24834] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 03/08/2021] [Indexed: 12/26/2022]
Abstract
Traumatic brain injury (TBI) by an external physical impact results in compromised brain function via undesired neuronal death. Following the injury, resident and peripheral immune cells, astrocytes, and neural stem cells (NSCs) cooperatively contribute to the recovery of the neuronal function after TBI. However, excessive pro‐inflammatory responses of immune cells, and the disappearance of endogenous NSCs at the injury site during the acute phase of TBI, can exacerbate TBI progression leading to incomplete healing. Therefore, positive outcomes may depend on early interventions to control the injury‐associated cellular milieu in the early phase of injury. Here, we explore electrical stimulation (ES) of the injury site in a rodent model (male Sprague–Dawley rats) to investigate its overall effect on the constituent brain cell phenotype and composition during the acute phase of TBI. Our data showed that a brief ES for 1 hr on day 2 of TBI promoted anti‐inflammatory phenotypes of microglia as assessed by CD206 expression and increased the population of NSCs and Nestin+ astrocytes at 7 days post‐TBI. Also, ES effectively increased the number of viable neurons when compared to the unstimulated control group. Given the salience of microglia and neural stem cells for healing after TBI, our results strongly support the potential benefit of the therapeutic use of ES during the acute phase of TBI to regulate neuroinflammation and to enhance neuroregeneration.
Collapse
Affiliation(s)
- Eunyoung Park
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Johnathan G Lyon
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, USA
| | - Melissa Alvarado-Velez
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Martha I Betancur
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, USA
| | - Nassir Mokarram
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, USA
| | - Jennifer H Shin
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Ravi V Bellamkonda
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, USA
| |
Collapse
|
5
|
Latchoumane CFV, Betancur MI, Simchick GA, Sun MK, Forghani R, Lenear CE, Ahmed A, Mohankumar R, Balaji N, Mason HD, Archer-Hartmann SA, Azadi P, Holmes PV, Zhao Q, Bellamkonda RV, Karumbaiah L. Engineered glycomaterial implants orchestrate large-scale functional repair of brain tissue chronically after severe traumatic brain injury. Sci Adv 2021; 7:7/10/eabe0207. [PMID: 33674306 PMCID: PMC7935369 DOI: 10.1126/sciadv.abe0207] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 01/21/2021] [Indexed: 05/14/2023]
Abstract
Severe traumatic brain injury (sTBI) survivors experience permanent functional disabilities due to significant volume loss and the brain's poor capacity to regenerate. Chondroitin sulfate glycosaminoglycans (CS-GAGs) are key regulators of growth factor signaling and neural stem cell homeostasis in the brain. However, the efficacy of engineered CS (eCS) matrices in mediating structural and functional recovery chronically after sTBI has not been investigated. We report that neurotrophic factor functionalized acellular eCS matrices implanted into the rat M1 region acutely after sTBI significantly enhanced cellular repair and gross motor function recovery when compared to controls 20 weeks after sTBI. Animals subjected to M2 region injuries followed by eCS matrix implantations demonstrated the significant recovery of "reach-to-grasp" function. This was attributed to enhanced volumetric vascularization, activity-regulated cytoskeleton (Arc) protein expression, and perilesional sensorimotor connectivity. These findings indicate that eCS matrices implanted acutely after sTBI can support complex cellular, vascular, and neuronal circuit repair chronically after sTBI.
Collapse
Affiliation(s)
- Charles-Francois V Latchoumane
- Regenerative Bioscience Center, University of Georgia, Athens, GA 30602, USA
- Edgar L. Rhodes Center for ADS, College of Agriculture and Environmental Sciences, University of Georgia, Athens, GA 30602, USA
| | - Martha I Betancur
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, 101 Science Drive, Durham, NC 27705, USA
| | - Gregory A Simchick
- Department of Physics and Astronomy, University of Georgia, Athens, GA 30602, USA
- Bio-Imaging Research Center, University of Georgia, Athens, GA 30602, USA
| | - Min Kyoung Sun
- Regenerative Bioscience Center, University of Georgia, Athens, GA 30602, USA
- Division of Neuroscience, Biomedical & Health Sciences Institute, University of Georgia, Athens, GA 30602, USA
| | - Rameen Forghani
- Regenerative Bioscience Center, University of Georgia, Athens, GA 30602, USA
| | - Christopher E Lenear
- Regenerative Bioscience Center, University of Georgia, Athens, GA 30602, USA
- Edgar L. Rhodes Center for ADS, College of Agriculture and Environmental Sciences, University of Georgia, Athens, GA 30602, USA
| | - Aws Ahmed
- Regenerative Bioscience Center, University of Georgia, Athens, GA 30602, USA
- Edgar L. Rhodes Center for ADS, College of Agriculture and Environmental Sciences, University of Georgia, Athens, GA 30602, USA
| | - Ramya Mohankumar
- Regenerative Bioscience Center, University of Georgia, Athens, GA 30602, USA
| | - Nivedha Balaji
- Regenerative Bioscience Center, University of Georgia, Athens, GA 30602, USA
| | - Hannah D Mason
- Regenerative Bioscience Center, University of Georgia, Athens, GA 30602, USA
| | | | - Parastoo Azadi
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA
| | - Philip V Holmes
- Division of Neuroscience, Biomedical & Health Sciences Institute, University of Georgia, Athens, GA 30602, USA
- Psychology Department, University of Georgia, Athens, GA 30602, USA
| | - Qun Zhao
- Regenerative Bioscience Center, University of Georgia, Athens, GA 30602, USA
- Department of Physics and Astronomy, University of Georgia, Athens, GA 30602, USA
- Bio-Imaging Research Center, University of Georgia, Athens, GA 30602, USA
| | - Ravi V Bellamkonda
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, 101 Science Drive, Durham, NC 27705, USA
| | - Lohitash Karumbaiah
- Regenerative Bioscience Center, University of Georgia, Athens, GA 30602, USA.
- Edgar L. Rhodes Center for ADS, College of Agriculture and Environmental Sciences, University of Georgia, Athens, GA 30602, USA
- Division of Neuroscience, Biomedical & Health Sciences Institute, University of Georgia, Athens, GA 30602, USA
| |
Collapse
|
6
|
Alvarado-Velez M, Enam SF, Mehta N, Lyon JG, LaPlaca MC, Bellamkonda RV. Immuno-suppressive hydrogels enhance allogeneic MSC survival after transplantation in the injured brain. Biomaterials 2020; 266:120419. [PMID: 33038594 DOI: 10.1016/j.biomaterials.2020.120419] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 09/15/2020] [Accepted: 09/20/2020] [Indexed: 12/20/2022]
Abstract
Traumatic brain injury (TBI) triggers multiple biochemical and cellular processes that exacerbate brain tissue damage through a secondary injury. Therapies that prevent or limit the evolution of secondary injury could significantly reduce the neurological deficits associated with TBI. Mesenchymal stem cell (MSC) transplantation after TBI can ameliorate neurological deficits by modulating inflammation and enhancing the expression of neurotrophic factors. However, transplanted MSCs can be actively rejected by host immune responses, such as those mediated by cytotoxic CD8+ T cells, thereby limiting their therapeutic efficacy. Here, we designed an agarose hydrogel that releases Fas ligand (FasL), a protein that can induce apoptosis of cytotoxic CD8+ T cells. We studied the immunosuppressive effect of this hydrogel near the allogeneic MSC transplantation site and its impact on the survival of transplanted MSCs in the injured brain. Agarose-FasL hydrogels locally reduced the host cytotoxic CD8+ T cell population and enhanced the survival of allogeneic MSCs transplanted near the injury site. Furthermore, the expression of crucial neurotrophic factors was elevated in the injury penumbra, suggesting an enhanced therapeutic effect of MSCs. These results suggest that the development of immunosuppressive hydrogels for stem cell delivery can enhance the benefits of stem cell therapy for TBI.
Collapse
Affiliation(s)
- Melissa Alvarado-Velez
- Dept. of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Syed Faaiz Enam
- Dept. of Biomedical Engineering, Duke University, Durham, NC, 27708, USA
| | - Nalini Mehta
- Dept. of Biomedical Engineering, Duke University, Durham, NC, 27708, USA
| | - Johnathan G Lyon
- Dept. of Biomedical Engineering, Duke University, Durham, NC, 27708, USA
| | - Michelle C LaPlaca
- Dept. of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Ravi V Bellamkonda
- Dept. of Biomedical Engineering, Duke University, Durham, NC, 27708, USA.
| |
Collapse
|
7
|
Hu HZ, Granger N, Pai SB, Bellamkonda RV, Jeffery ND. Therapeutic efficacy of microtube-embedded chondroitinase ABC in a canine clinical model of spinal cord injury. Brain 2019; 141:1017-1027. [PMID: 29444239 DOI: 10.1093/brain/awy007] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 11/28/2017] [Indexed: 01/26/2023] Open
Abstract
See Moon and Bradbury (doi:10.1093/brain/awy067) for a scientific commentary on this article.Many hundreds of thousands of people around the world are living with the long-term consequences of spinal cord injury and they need effective new therapies. Laboratory research in experimental animals has identified a large number of potentially translatable interventions but transition to the clinic is not straightforward. Further evidence of efficacy in more clinically-relevant lesions is required to gain sufficient confidence to commence human clinical trials. Of the many therapeutic candidates currently available, intraspinally applied chondroitinase ABC has particularly well documented efficacy in experimental animals. In this study we measured the effects of this intervention in a double-blinded randomized controlled trial in a cohort of dogs with naturally-occurring severe chronic spinal cord injuries that model the condition in humans. First, we collected baseline data on a series of outcomes: forelimb-hindlimb coordination (the prespecified primary outcome measure), skin sensitivity along the back, somatosensory evoked and transcranial magnetic motor evoked potentials and cystometry in 60 dogs with thoracolumbar lesions. Dogs were then randomized 1:1 to receive intraspinal injections of heat-stabilized, lipid microtube-embedded chondroitinase ABC or sham injections consisting of needle puncture of the skin. Outcome data were measured at 1, 3 and 6 months after intervention; skin sensitivity was also measured 24 h after injection (or sham). Forelimb-hindlimb coordination was affected by neither time nor chondroitinase treatment alone but there was a significant interaction between these variables such that coordination between forelimb and hindlimb stepping improved during the 6-month follow-up period in the chondroitinase-treated animals by a mean of 23%, but did not change in controls. Three dogs (10%) in the chondroitinase group also recovered the ability to ambulate without assistance. Sensitivity of the dorsal skin increased at 24 h after intervention in both groups but subsequently decreased to normal levels. Cystometry identified a non-significant improvement of bladder compliance at 1 month in the chondroitinase-injected dogs but this did not persist. There were no overall differences between groups in detection of sensory evoked potentials. Our results strongly support a beneficial effect of intraspinal injection of chondroitinase ABC on spinal cord function in this highly clinically-relevant model of chronic severe spinal cord injury. There was no evidence of long-term adverse effects associated with this intervention. We therefore conclude that this study provides strong evidence in support of initiation of clinical trials of chondroitinase ABC in humans with chronic spinal cord injury.
Collapse
Affiliation(s)
- Hilary Z Hu
- 1 College of Veterinary Medicine, Iowa State University, 1800 Christensen Drive, Ames IA 50011, USA
| | - Nicolas Granger
- 2 Royal Veterinary College, Hawkshead Lane, Hatfield, Hertfordshire, AL9 7TA, UK
| | - S Balakrishna Pai
- 3 Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, 313 Ferst Drive, Atlanta, GA 30332, USA
| | - Ravi V Bellamkonda
- 4 Department of Biomedical Engineering, Duke University Pratt School of Engineering, 101 Science Drive, Campus Box 90281, Durham NC 27708, USA
| | - Nick D Jeffery
- 1 College of Veterinary Medicine, Iowa State University, 1800 Christensen Drive, Ames IA 50011, USA
| |
Collapse
|
8
|
Falcone JD, Sohal HS, Kyriakides TR, Bellamkonda RV. The impact of modulating the blood-brain barrier on the electrophysiological and histological outcomes of intracortical electrodes. J Neural Eng 2019; 16:046005. [PMID: 31048574 DOI: 10.1088/1741-2552/ab1ef9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
OBJECTIVE Successful application of chronic intracortical electrodes remains highly variable. The biological mechanisms leading to electrode failure are still being explored. Recent work has shown a correlation between blood-brain barrier (BBB) integrity and long-term recordings. Here we proposed to modulate the BBB healing after intracortical electrode implantation, while evaluating the functional electrophysiology. The CCL2/CCR2 pathway was chosen based on previous work demonstrating the positive histological effects in an intracortical electrode model, as well as in other neurodegenerative models. By disrupting this pathway, recruitment of pro-inflammatory monocytes (a result of a breached BBB) is potentially reduced at the electrode interface. APPROACH Michigan electrodes were implanted for 2 and 12 weeks in rats, and a CCR2 antagonist (RS 102895) was administered daily to the treatment group. Functional electrodes were used for the 12 week cohort, and weekly electrophysiological recordings were taken. At 2 and 12 weeks, histology was analyzed. MAIN RESULTS At 12 weeks, the CCR2-antagonist group had significantly higher signal-to-noise ratios (SNRs) than control. CCR2-antagonism at 2 weeks significantly increased the neural population and decreased BBB breach. At 12 weeks, CCR2-antagonism significantly increased number of neurons and BBB + vasculature within 100 µm of the electrode interface. SIGNIFICANCE This work demonstrates that for intracortical electrodes, disruption of the CCL2/CCR2 pathway improves chronic outcomes in electrophysiology and histology.
Collapse
Affiliation(s)
- Jessica D Falcone
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA, United States of America
| | | | | | | |
Collapse
|
9
|
Saxena T, Lyon JG, Pai SB, Pare D, Amero J, Karumbaiah L, Carroll SL, Gaupp E, Bellamkonda RV. Engineering Controlled Peritumoral Inflammation to Constrain Brain Tumor Growth. Adv Healthc Mater 2019; 8:e1801076. [PMID: 30537355 DOI: 10.1002/adhm.201801076] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 10/23/2018] [Indexed: 02/06/2023]
Abstract
Brain tumors remain a great clinical challenge, in part due to their capacity to invade into eloquent, inoperable regions of the brain. In contrast, inflammation in the central nervous system (CNS) due to injuries activates microglia and astrocytes culminating in an astroglial scar that typically "walls-off" the injury site. Here, the hypothesis is tested that targeting peritumoral cells surrounding tumors to activate them via an inflammatory stimulus that recapitulates the sequelae of a traumatic CNS injury, could generate an environment that would wall-off and contain invasive tumors in the brain. Gold nanoparticles coated with inflammatory polypeptides to target stromal cells in close vicinity to glioblastoma (GBM) tumors, in order to activate these cells and stimulate stromal CNS inflammation, are engineered. It is reported that this approach significantly contains tumors in rodent models of GBM relative to control treatments (reduction in tumor volume by over 300% in comparison to controls), by the activation of the innate and adaptive immune response, and by triggering pathways related to cell clustering. Overall, this report outlines an approach to contain invasive tumors that can complement adjuvant interventions for invasive GBM such as radiation and chemotherapy.
Collapse
Affiliation(s)
- Tarun Saxena
- Department of Biomedical EngineeringPratt School of EngineeringDuke University 101 Science Drive Durham NC 27705 USA
| | - Johnathan G. Lyon
- Department of Biomedical EngineeringPratt School of EngineeringDuke University 101 Science Drive Durham NC 27705 USA
| | - S. Balakrishna Pai
- Wallace H. Coulter Department of Biomedical EngineeringGeorgia Institute of Technology & Emory School of MedicineUA Whitaker Building 313 Ferst Drive Atlanta GA 30332 USA
| | - Daniel Pare
- Wallace H. Coulter Department of Biomedical EngineeringGeorgia Institute of Technology & Emory School of MedicineUA Whitaker Building 313 Ferst Drive Atlanta GA 30332 USA
| | - Jessica Amero
- Wallace H. Coulter Department of Biomedical EngineeringGeorgia Institute of Technology & Emory School of MedicineUA Whitaker Building 313 Ferst Drive Atlanta GA 30332 USA
| | - Lohitash Karumbaiah
- Regenerative Bioscience CenterThe University of Georgia 425 River Road, ADS Complex Athens GA 30602 USA
| | - Sheridan L. Carroll
- Department of Biomedical EngineeringPratt School of EngineeringDuke University 101 Science Drive Durham NC 27705 USA
| | - Eric Gaupp
- Wallace H. Coulter Department of Biomedical EngineeringGeorgia Institute of Technology & Emory School of MedicineUA Whitaker Building 313 Ferst Drive Atlanta GA 30332 USA
| | - Ravi V. Bellamkonda
- Department of Biomedical EngineeringPratt School of EngineeringDuke University 101 Science Drive Durham NC 27705 USA
| |
Collapse
|
10
|
Loomis KH, Lindsay KE, Zurla C, Bhosle SM, Vanover DA, Blanchard EL, Kirschman JL, Bellamkonda RV, Santangelo PJ. In Vitro Transcribed mRNA Vaccines with Programmable Stimulation of Innate Immunity. Bioconjug Chem 2018; 29:3072-3083. [PMID: 30067354 DOI: 10.1021/acs.bioconjchem.8b00443] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
In vitro transcribed (IVT) mRNA is an appealing platform for next generation vaccines, as it can be manufactured rapidly at large scale to meet emerging pathogens. However, its performance as a robust vaccine is strengthened by supplemental immune stimulation, which is typically provided by adjuvant formulations that facilitate delivery and stimulate immune responses. Here, we present a strategy for increasing translation of a model IVT mRNA vaccine while simultaneously modulating its immune-stimulatory properties in a programmable fashion, without relying on delivery vehicle formulations. Substitution of uridine with the modified base N1-methylpseudouridine reduces the intrinsic immune stimulation of the IVT mRNA and enhances antigen translation. Tethering adjuvants to naked IVT mRNA through antisense nucleotides boosts the immunostimulatory properties of adjuvants in vitro, without impairing transgene production or adjuvant activity. In vivo, intramuscular injection of tethered IVT mRNA-TLR7 agonists leads to enhanced local immune responses, and to antigen-specific cell-mediated and humoral responses. We believe this system represents a potential platform compatible with any adjuvant of interest to enable specific programmable stimulation of immune responses.
Collapse
Affiliation(s)
- Kristin H Loomis
- Wallace H. Coulter Department of Biomedical Engineering , Georgia Institute of Technology and Emory University , Krone Engineering Biosystems Building, 950 Atlantic Drive , Atlanta , Georgia 30332 , United States
| | - Kevin E Lindsay
- Wallace H. Coulter Department of Biomedical Engineering , Georgia Institute of Technology and Emory University , Krone Engineering Biosystems Building, 950 Atlantic Drive , Atlanta , Georgia 30332 , United States
| | - Chiara Zurla
- Wallace H. Coulter Department of Biomedical Engineering , Georgia Institute of Technology and Emory University , Krone Engineering Biosystems Building, 950 Atlantic Drive , Atlanta , Georgia 30332 , United States
| | - Sushma M Bhosle
- Wallace H. Coulter Department of Biomedical Engineering , Georgia Institute of Technology and Emory University , Krone Engineering Biosystems Building, 950 Atlantic Drive , Atlanta , Georgia 30332 , United States
| | - Daryll A Vanover
- Wallace H. Coulter Department of Biomedical Engineering , Georgia Institute of Technology and Emory University , Krone Engineering Biosystems Building, 950 Atlantic Drive , Atlanta , Georgia 30332 , United States
| | - Emmeline L Blanchard
- Wallace H. Coulter Department of Biomedical Engineering , Georgia Institute of Technology and Emory University , Krone Engineering Biosystems Building, 950 Atlantic Drive , Atlanta , Georgia 30332 , United States
| | - Jonathan L Kirschman
- Wallace H. Coulter Department of Biomedical Engineering , Georgia Institute of Technology and Emory University , Krone Engineering Biosystems Building, 950 Atlantic Drive , Atlanta , Georgia 30332 , United States
| | - Ravi V Bellamkonda
- Wallace H. Coulter Department of Biomedical Engineering , Georgia Institute of Technology and Emory University , Krone Engineering Biosystems Building, 950 Atlantic Drive , Atlanta , Georgia 30332 , United States
| | - Philip J Santangelo
- Wallace H. Coulter Department of Biomedical Engineering , Georgia Institute of Technology and Emory University , Krone Engineering Biosystems Building, 950 Atlantic Drive , Atlanta , Georgia 30332 , United States
| |
Collapse
|
11
|
Hogan SR, Phan JH, Alvarado-Velez M, Wang MD, Bellamkonda RV, Fernández FM, LaPlaca MC. Discovery of Lipidome Alterations Following Traumatic Brain Injury via High-Resolution Metabolomics. J Proteome Res 2018; 17:2131-2143. [PMID: 29671324 DOI: 10.1021/acs.jproteome.8b00068] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Traumatic brain injury (TBI) can occur across wide segments of the population, presenting in a heterogeneous manner that makes diagnosis inconsistent and management challenging. Biomarkers offer the potential to objectively identify injury status, severity, and phenotype by measuring the relative concentrations of endogenous molecules in readily accessible biofluids. Through a data-driven, discovery approach, novel biomarker candidates for TBI were identified in the serum lipidome of adult male Sprague-Dawley rats in the first week following moderate controlled cortical impact (CCI). Serum samples were analyzed in positive and negative modes by ultraperformance liquid chromatography-mass spectrometry (UPLC-MS). A predictive panel for the classification of injured and uninjured sera samples, consisting of 26 dysregulated species belonging to a variety of lipid classes, was developed with a cross-validated accuracy of 85.3% using omniClassifier software to optimize feature selection. Polyunsaturated fatty acids (PUFAs) and PUFA-containing diacylglycerols were found to be upregulated in sera from injured rats, while changes in sphingolipids and other membrane phospholipids were also observed, many of which map to known secondary injury pathways. Overall, the identified biomarker panel offers viable molecular candidates representing lipids that may readily cross the blood-brain barrier (BBB) and aid in the understanding of TBI pathophysiology.
Collapse
Affiliation(s)
- Scott R Hogan
- School of Chemistry and Biochemistry , Georgia Institute of Technology , Atlanta , Georgia 30332 , United States
| | - John H Phan
- Wallace H Coulter Department of Biomedical Engineering , Georgia Institute of Technology , Atlanta , Georgia 30332 , United States
| | - Melissa Alvarado-Velez
- Wallace H Coulter Department of Biomedical Engineering , Georgia Institute of Technology , Atlanta , Georgia 30332 , United States
| | - May Dongmei Wang
- Wallace H Coulter Department of Biomedical Engineering , Georgia Institute of Technology , Atlanta , Georgia 30332 , United States
| | - Ravi V Bellamkonda
- Wallace H Coulter Department of Biomedical Engineering , Georgia Institute of Technology , Atlanta , Georgia 30332 , United States
| | - Facundo M Fernández
- School of Chemistry and Biochemistry , Georgia Institute of Technology , Atlanta , Georgia 30332 , United States
| | - Michelle C LaPlaca
- Wallace H Coulter Department of Biomedical Engineering , Georgia Institute of Technology , Atlanta , Georgia 30332 , United States
| |
Collapse
|
12
|
Lee Y, Pai SB, Bellamkonda RV, Thompson DH, Singh J. Cerivastatin Nanoliposome as a Potential Disease Modifying Approach for the Treatment of Pulmonary Arterial Hypertension. J Pharmacol Exp Ther 2018; 366:66-74. [PMID: 29695410 DOI: 10.1124/jpet.118.247643] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 04/23/2018] [Indexed: 11/22/2022] Open
Abstract
In this study we investigated nanoliposome as an approach to tailoring the pharmacology of cerivastatin as a disease-modifying drug for pulmonary arterial hypertension (PAH). Cerivastatin encapsulated liposomes with an average diameter of 98 ± 27 nm were generated by a thin film and freeze-thaw process. The nanoliposomes demonstrated sustained drug-release kinetics in vitro and inhibited proliferation of pulmonary artery (PA) smooth muscle cells with significantly less cellular cytotoxicity as compared with free cerivastatin. When delivered by inhalation to a rat model of monocrotaline-induced PAH, cerivastatin significantly reduced PA pressure from 55.13 ± 9.82 to 35.56 ± 6.59 mm Hg (P < 0.001) and diminished PA wall thickening. Echocardiography showed that cerivastatin significantly reduced right ventricle thickening (monocrotaline: 0.34 ± 0.02 cm vs. cerivastatin: 0.26 ± 0.02 cm; P < 0.001) and increased PA acceleration time (monocrotaline: 13.98 ± 1.14 milliseconds vs. cerivastatin: 21.07 ± 2.80 milliseconds; P < 0.001). Nanoliposomal cerivastatin was equally effective or slightly better than cerivastatin in reducing PA pressure (monocrotaline: 67.06 ± 13.64 mm Hg; cerivastatin: 46.31 ± 7.64 mm Hg vs. liposomal cerivastatin: 37.32 ± 9.50 mm Hg) and improving parameters of right ventricular function as measured by increasing PA acceleration time (monocrotaline: 24.68 ± 3.92 milliseconds; cerivastatin: 32.59 ± 6.10 milliseconds vs. liposomal cerivastatin: 34.96 ± 7.51 milliseconds). More importantly, the rate and magnitude of toxic cerivastatin metabolite lactone generation from the intratracheally administered nanoliposomes was significantly lower as compared with intravenously administered free cerivastatin. These studies show that nanoliposome encapsulation improved in vitro and in vivo pharmacologic and safety profile of cerivastatin and may represent a safer approach as a disease-modifying therapy for PAH.
Collapse
Affiliation(s)
- Young Lee
- Indiana Center for Biomedical Innovation, School of Medicine, Indiana University, Indianapolis, Indiana (Y.L., J.S.); Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and School of Medicine, Emory University, Atlanta, Georgia (S.B.P., R.V.B.); Department of Biomedical Engineering, Duke University, Durham, North Carolina (R.V.B.); and Department of Chemistry, Purdue University, West Lafayette, Indiana (Y.L., D.H.T.)
| | - S Balakrishna Pai
- Indiana Center for Biomedical Innovation, School of Medicine, Indiana University, Indianapolis, Indiana (Y.L., J.S.); Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and School of Medicine, Emory University, Atlanta, Georgia (S.B.P., R.V.B.); Department of Biomedical Engineering, Duke University, Durham, North Carolina (R.V.B.); and Department of Chemistry, Purdue University, West Lafayette, Indiana (Y.L., D.H.T.)
| | - Ravi V Bellamkonda
- Indiana Center for Biomedical Innovation, School of Medicine, Indiana University, Indianapolis, Indiana (Y.L., J.S.); Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and School of Medicine, Emory University, Atlanta, Georgia (S.B.P., R.V.B.); Department of Biomedical Engineering, Duke University, Durham, North Carolina (R.V.B.); and Department of Chemistry, Purdue University, West Lafayette, Indiana (Y.L., D.H.T.)
| | - David H Thompson
- Indiana Center for Biomedical Innovation, School of Medicine, Indiana University, Indianapolis, Indiana (Y.L., J.S.); Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and School of Medicine, Emory University, Atlanta, Georgia (S.B.P., R.V.B.); Department of Biomedical Engineering, Duke University, Durham, North Carolina (R.V.B.); and Department of Chemistry, Purdue University, West Lafayette, Indiana (Y.L., D.H.T.)
| | - Jaipal Singh
- Indiana Center for Biomedical Innovation, School of Medicine, Indiana University, Indianapolis, Indiana (Y.L., J.S.); Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and School of Medicine, Emory University, Atlanta, Georgia (S.B.P., R.V.B.); Department of Biomedical Engineering, Duke University, Durham, North Carolina (R.V.B.); and Department of Chemistry, Purdue University, West Lafayette, Indiana (Y.L., D.H.T.)
| |
Collapse
|
13
|
Falcone JD, Carroll SL, Saxena T, Mandavia D, Clark A, Yarabarla V, Bellamkonda RV. Correlation of mRNA Expression and Signal Variability in Chronic Intracortical Electrodes. Front Bioeng Biotechnol 2018; 6:26. [PMID: 29637071 PMCID: PMC5880884 DOI: 10.3389/fbioe.2018.00026] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 03/06/2018] [Indexed: 01/08/2023] Open
Abstract
Objective The goal for this research was to identify molecular mechanisms that explain animal-to-animal variability in chronic intracortical recordings. Approach Microwire electrodes were implanted into Sprague Dawley rats at an acute (1 week) and a chronic (14 weeks) time point. Weekly recordings were conducted, and action potentials were evoked in the barrel cortex by deflecting the rat’s whiskers. At 1 and 14 weeks, tissue was collected, and mRNA was extracted. mRNA expression was compared between 1 and 14 weeks using a high throughput multiplexed qRT-PCR. Pearson correlation coefficients were calculated between mRNA expression and signal-to-noise ratios at 14 weeks. Main results At 14 weeks, a positive correlation between signal-to-noise ratio (SNR) and NeuN and GFAP mRNA expression was observed, indicating a relationship between recording strength and neuronal population, as well as reactive astrocyte activity. The inflammatory state around the electrode interface was evaluated using M1-like and M2-like markers. Expression for both M1-like and M2-like mRNA markers remained steady from 1 to 14 weeks. Anti-inflammatory markers, CD206 and CD163, however, demonstrated a significant positive correlation with SNR quality at 14 weeks. VE-cadherin, a marker for adherens junctions, and PDGFR-β, a marker for pericytes, both partial representatives of blood–brain barrier health, had a positive correlation with SNR at 14 weeks. Endothelial adhesion markers revealed a significant increase in expression at 14 weeks, while CD45, a pan-leukocyte marker, significantly decreased at 14 weeks. No significant correlation was found for either the endothelial adhesion or pan-leukocyte markers. Significance A positive correlation between anti-inflammatory and blood–brain barrier health mRNA markers with electrophysiological efficacy of implanted intracortical electrodes has been demonstrated. These data reveal potential mechanisms for further evaluation to determine potential target mechanisms to improve consistency of intracortical electrodes recordings and reduce animal-to-animal/implant-to-implant variability.
Collapse
Affiliation(s)
- Jessica D Falcone
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA, United States
| | - Sheridan L Carroll
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
| | - Tarun Saxena
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
| | - Dev Mandavia
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA, United States
| | - Alexus Clark
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA, United States
| | - Varun Yarabarla
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA, United States
| | - Ravi V Bellamkonda
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
| |
Collapse
|
14
|
Enam SF, Krieger JR, Saxena T, Watts BE, Olingy CE, Botchwey EA, Bellamkonda RV. Enrichment of endogenous fractalkine and anti-inflammatory cells via aptamer-functionalized hydrogels. Biomaterials 2017; 142:52-61. [PMID: 28727998 DOI: 10.1016/j.biomaterials.2017.07.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Revised: 06/27/2017] [Accepted: 07/09/2017] [Indexed: 12/27/2022]
Abstract
Early recruitment of non-classical monocytes and their macrophage derivatives is associated with augmented tissue repair and improved integration of biomaterial constructs. A promising therapeutic approach to recruit these subpopulations is by elevating local concentrations of chemoattractants such as fractalkine (FKN, CX3CL1). However, delivering recombinant or purified proteins is not ideal due to their short half-lives, suboptimal efficacy, immunogenic potential, batch variabilities, and cost. Here we report an approach to enrich endogenous FKN, obviating the need for delivery of exogenous proteins. In this study, modified FKN-binding-aptamers are integrated with poly(ethylene glycol) diacrylate to form aptamer-functionalized hydrogels ("aptagels") that localize, dramatically enrich and passively release FKN in vitro for at least one week. Implantation in a mouse model of excisional skin injury demonstrates that aptagels enrich endogenous FKN and stimulate significant local increases in Ly6CloCX3CR1hi non-classical monocytes and CD206+ M2-like macrophages. The results demonstrate that orchestrators of inflammation can be manipulated without delivery of foreign proteins or cells and FKN-aptamer functionalized biomaterials may be a promising approach to recruit anti-inflammatory subpopulations to sites of injury. Aptagels are readily synthesized, highly customizable and could combine different aptamers to treat complex diseases in which regulation or enrichment of multiple proteins may be therapeutic.
Collapse
Affiliation(s)
- Syed Faaiz Enam
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
| | - Jack R Krieger
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, Atlanta, GA 30332, USA
| | - Tarun Saxena
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
| | - Brian E Watts
- Duke Human Vaccine Institute, Duke University, Durham, NC 27708, USA
| | - Claire E Olingy
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, Atlanta, GA 30332, USA
| | - Edward A Botchwey
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, Atlanta, GA 30332, USA
| | - Ravi V Bellamkonda
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA.
| |
Collapse
|
15
|
Betancur MI, Mason HD, Alvarado-Velez M, Holmes PV, Bellamkonda RV, Karumbaiah L. Chondroitin Sulfate Glycosaminoglycan Matrices Promote Neural Stem Cell Maintenance and Neuroprotection Post-Traumatic Brain Injury. ACS Biomater Sci Eng 2017; 3:420-430. [PMID: 29744379 PMCID: PMC5937277 DOI: 10.1021/acsbiomaterials.6b00805] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
There are currently no effective treatments for moderate-to-severe traumatic brain injuries (TBIs). The paracrine functions of undifferentiated neural stem cells (NSCs) are believed to play a significant role in stimulating the repair and regeneration of injured brain tissue. We therefore hypothesized that fibroblast growth factor (FGF2) enriching chondroitin sulfate glycosaminoglycan (CS-GAG) matrices can maintain the undifferentiated state of neural stem cells (NSCs) and facilitate brain tissue repair subacutely post-TBI. Rats subjected to a controlled cortical impactor (CCI) induced TBI were intraparenchymally injected with CS-GAG matrices alone or with CS-GAG matrices containing PKH26GL labeled allogeneic NSCs. Nissl staining of brain tissue 4 weeks post-TBI demonstrated the significantly enhanced (p < 0.05) tissue protection in CS-GAG treated animals when compared to TBI only control, and NSC only treated animals. CS-GAG-NSC treated animals demonstrated significantly enhanced (p < 0.05) FGF2 retention, and maintenance of PKH26GL labeled NSCs as indicated by enhanced Sox1+ and Ki67+ cell presence over other differentiated cell types. Lastly, all treatment groups and sham controls exhibited a significantly (p < 0.05) attenuated GFAP+ reactive astrocyte presence in the lesion site when compared to TBI only controls.
Collapse
Affiliation(s)
- Martha I. Betancur
- Regenerative Bioscience Center, The University of Georgia, 425 River Road, ADS Complex, Athens, Georgia 30602, United States
| | - Hannah D. Mason
- Regenerative Bioscience Center, The University of Georgia, 425 River Road, ADS Complex, Athens, Georgia 30602, United States
| | - Melissa Alvarado-Velez
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, 313 Ferst Drive, Atlanta, Georgia 30332, United States
| | - Phillip V. Holmes
- Psychology Department, The University of Georgia, 125 Baldwin Street, Athens, Georgia 30602, United States
| | - Ravi V. Bellamkonda
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, 313 Ferst Drive, Atlanta, Georgia 30332, United States
| | - Lohitash Karumbaiah
- Regenerative Bioscience Center, The University of Georgia, 425 River Road, ADS Complex, Athens, Georgia 30602, United States
| |
Collapse
|
16
|
Patel YA, Saxena T, Bellamkonda RV, Butera RJ. Kilohertz frequency nerve block enhances anti-inflammatory effects of vagus nerve stimulation. Sci Rep 2017; 7:39810. [PMID: 28054557 PMCID: PMC5215548 DOI: 10.1038/srep39810] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Accepted: 11/25/2016] [Indexed: 11/29/2022] Open
Abstract
Efferent activation of the cervical vagus nerve (cVN) dampens systemic inflammatory processes, potentially modulating a wide-range of inflammatory pathological conditions. In contrast, afferent cVN activation amplifies systemic inflammatory processes, leading to activation of the hypothalamic-pituitary-adrenal (HPA) axis, the sympathetic nervous system through the greater splanchnic nerve (GSN), and elevation of pro-inflammatory cytokines. Ideally, to clinically implement anti-inflammatory therapy via cervical vagus nerve stimulation (cVNS) one should selectively activate the efferent pathway. Unfortunately, current implementations, in animal and clinical investigations, activate both afferent and efferent pathways. We paired cVNS with kilohertz electrical stimulation (KES) nerve block to preferentially activate efferent pathways while blocking afferent pathways. Selective efferent cVNS enhanced the anti-inflammatory effects of cVNS. Our results demonstrate that: (i) afferent, but not efferent, cVNS synchronously activates the GSN in a dose-dependent manner; (ii) efferent cVNS enabled by complete afferent KES nerve block enhances the anti-inflammatory benefits of cVNS; and (iii) incomplete afferent KES nerve block exacerbates systemic inflammation. Overall, these data demonstrate the utility of paired efferent cVNS and afferent KES nerve block for achieving selective efferent cVNS, specifically as it relates to neuromodulation of systemic inflammation.
Collapse
Affiliation(s)
- Yogi A Patel
- Georgia Institute of Technology, Department of Biomedical Engineering, Atlanta, GA, 30332 USA.,Georgia Institute of Technology, Bioengineering Graduate Program, Atlanta, GA, 30332 USA.,Georgia Institute of Technology, Neural Engineering Center, Atlanta, GA, 30332 USA
| | - Tarun Saxena
- Duke University, Department of Biomedical Engineering, Durham, NC 27708 USA
| | - Ravi V Bellamkonda
- Duke University, Department of Biomedical Engineering, Durham, NC 27708 USA
| | - Robert J Butera
- Georgia Institute of Technology, Department of Biomedical Engineering, Atlanta, GA, 30332 USA.,Georgia Institute of Technology, Bioengineering Graduate Program, Atlanta, GA, 30332 USA.,Georgia Institute of Technology, Neural Engineering Center, Atlanta, GA, 30332 USA.,Georgia Institute of Technology, School of Electrical and Computer Engineering, Atlanta, GA 30332 USA
| |
Collapse
|
17
|
Mehta N, Lyon JG, Patil K, Mokarram N, Kim C, Bellamkonda RV. Bacterial Carriers for Glioblastoma Therapy. Mol Ther Oncolytics 2016; 4:1-17. [PMID: 28345020 PMCID: PMC5363759 DOI: 10.1016/j.omto.2016.12.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 12/04/2016] [Indexed: 01/22/2023]
Abstract
Treatment of aggressive glioblastoma brain tumors is challenging, largely due to diffusion barriers preventing efficient drug dosing to tumors. To overcome these barriers, bacterial carriers that are actively motile and programmed to migrate and localize to tumor zones were designed. These carriers can induce apoptosis via hypoxia-controlled expression of a tumor suppressor protein p53 and a pro-apoptotic drug, Azurin. In a xenograft model of human glioblastoma in rats, bacterial carrier therapy conferred a significant survival benefit with 19% overall long-term survival of >100 days in treated animals relative to a median survival of 26 days in control untreated animals. Histological and proteomic analyses were performed to elucidate the safety and efficacy of these carriers, showing an absence of systemic toxicity and a restored neural environment in treated responders. In the treated non-responders, proteomic analysis revealed competing mechanisms of pro-apoptotic and drug-resistant activity. This bacterial carrier opens a versatile avenue to overcome diffusion barriers in glioblastoma by virtue of its active motility in extracellular space and can lead to tailored therapies via tumor-specific expression of tumoricidal proteins.
Collapse
Affiliation(s)
- Nalini Mehta
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, UA Whitaker Building, 313 Ferst Drive, Atlanta, GA 30332, USA
| | - Johnathan G Lyon
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, UA Whitaker Building, 313 Ferst Drive, Atlanta, GA 30332, USA; Department of Biomedical Engineering, Pratt School of Engineering, Duke University, 101 Science Drive, Durham, NC 27708-0271, USA
| | - Ketki Patil
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, UA Whitaker Building, 313 Ferst Drive, Atlanta, GA 30332, USA
| | - Nassir Mokarram
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, 101 Science Drive, Durham, NC 27708-0271, USA
| | - Christine Kim
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, UA Whitaker Building, 313 Ferst Drive, Atlanta, GA 30332, USA
| | - Ravi V Bellamkonda
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, 101 Science Drive, Durham, NC 27708-0271, USA
| |
Collapse
|
18
|
Gollnick CA, Millard DC, Ortiz AD, Bellamkonda RV, Stanley GB. Response reliability observed with voltage-sensitive dye imaging of cortical layer 2/3: the probability of activation hypothesis. J Neurophysiol 2016; 115:2456-69. [PMID: 26864758 DOI: 10.1152/jn.00547.2015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Accepted: 02/04/2016] [Indexed: 11/22/2022] Open
Abstract
A central assertion in the study of neural processing is that our perception of the environment directly reflects the activity of our sensory neurons. This assertion reinforces the intuition that the strength of a sensory input directly modulates the amount of neural activity observed in response to that sensory feature: an increase in the strength of the input yields a graded increase in the amount of neural activity. However, cortical activity across a range of sensory pathways can be sparse, with individual neurons having remarkably low firing rates, often exhibiting suprathreshold activity on only a fraction of experimental trials. To compensate for this observed apparent unreliability, it is assumed that instead the local population of neurons, although not explicitly measured, does reliably represent the strength of the sensory input. This assumption, however, is largely untested. In this study, using wide-field voltage-sensitive dye (VSD) imaging of the somatosensory cortex in the anesthetized rat, we show that whisker deflection velocity, or stimulus strength, is not encoded by the magnitude of the population response at the level of cortex. Instead, modulation of whisker deflection velocity affects the likelihood of the cortical response, impacting the magnitude, rate of change, and spatial extent of the cortical response. An ideal observer analysis of the cortical response points to a probabilistic code based on repeated sampling across cortical columns and/or time, which we refer to as the probability of activation hypothesis. This hypothesis motivates a range of testable predictions for both future electrophysiological and future behavioral studies.
Collapse
Affiliation(s)
- Clare A Gollnick
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, Georgia
| | - Daniel C Millard
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, Georgia
| | - Alexander D Ortiz
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, Georgia
| | - Ravi V Bellamkonda
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, Georgia
| | - Garrett B Stanley
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, Georgia
| |
Collapse
|
19
|
Affiliation(s)
- Tarun Saxena
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, UA Whitaker Building, 313 Ferst Drive, Atlanta, Georgia 30332, USA
| | - Ravi V Bellamkonda
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, UA Whitaker Building, 313 Ferst Drive, Atlanta, Georgia 30332, USA
| |
Collapse
|
20
|
Srinivasan A, Tipton J, Tahilramani M, Kharbouch A, Gaupp E, Song C, Venkataraman P, Falcone J, Lacour SP, Stanley GB, English AW, Bellamkonda RV. A regenerative microchannel device for recording multiple single-unit action potentials in awake, ambulatory animals. Eur J Neurosci 2015; 43:474-85. [PMID: 26370722 DOI: 10.1111/ejn.13080] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 08/07/2015] [Accepted: 09/08/2015] [Indexed: 12/28/2022]
Abstract
Despite significant advances in robotics, commercially advanced prosthetics provide only a small fraction of the functionality of the amputated limb that they are meant to replace. Peripheral nerve interfacing could provide a rich controlling link between the body and these advanced prosthetics in order to increase their overall utility. Here, we report on the development of a fully integrated regenerative microchannel interface with 30 microelectrodes and signal extraction capabilities enabling evaluation in an awake and ambulatory rat animal model. In vitro functional testing validated the capability of the microelectrodes to record neural signals similar in size and nature to those that occur in vivo. In vitro dorsal root ganglia cultures revealed striking cytocompatibility of the microchannel interface. Finally, in vivo, the microchannel interface was successfully used to record a multitude of single-unit action potentials through 63% of the integrated microelectrodes at the early time point of 3 weeks. This marks a significant advance in microchannel interfacing, demonstrating the capability of microchannels to be used for peripheral nerve interfacing.
Collapse
Affiliation(s)
- Akhil Srinivasan
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, 313 Ferst Drive, Atlanta, GA, 30332, USA
| | - John Tipton
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, 313 Ferst Drive, Atlanta, GA, 30332, USA
| | - Mayank Tahilramani
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, 313 Ferst Drive, Atlanta, GA, 30332, USA
| | - Adel Kharbouch
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, 313 Ferst Drive, Atlanta, GA, 30332, USA
| | - Eric Gaupp
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, 313 Ferst Drive, Atlanta, GA, 30332, USA
| | - Chao Song
- School of Electrical and Computer Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA, USA
| | - Poornima Venkataraman
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, 313 Ferst Drive, Atlanta, GA, 30332, USA
| | - Jessica Falcone
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, 313 Ferst Drive, Atlanta, GA, 30332, USA
| | - Stéphanie P Lacour
- Centre for Neuroprosthetics, School of Engineering, Institute of Microengineering and Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne, Switzerland
| | - Garrett B Stanley
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, 313 Ferst Drive, Atlanta, GA, 30332, USA
| | - Arthur W English
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, USA
| | - Ravi V Bellamkonda
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, 313 Ferst Drive, Atlanta, GA, 30332, USA
| |
Collapse
|
21
|
Karumbaiah L, Enam SF, Brown AC, Saxena T, Betancur MI, Barker TH, Bellamkonda RV. Chondroitin Sulfate Glycosaminoglycan Hydrogels Create Endogenous Niches for Neural Stem Cells. Bioconjug Chem 2015; 26:2336-49. [PMID: 26440046 DOI: 10.1021/acs.bioconjchem.5b00397] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Neural stem cells (NSCs) possess great potential for neural tissue repair after traumatic injuries to the central nervous system (CNS). However, poor survival and self-renewal of NSCs after injury severely limits its therapeutic potential. Sulfated chondroitin sulfate glycosaminoglycans (CS-GAGs) linked to CS proteoglycans (CSPGs) in the brain extracellular matrix (ECM) have the ability to bind and potentiate trophic factor efficacy, and promote NSC self-renewal in vivo. In this study, we investigated the potential of CS-GAG hydrogels composed of monosulfated CS-4 (CS-A), CS-6 (CS-C), and disulfated CS-4,6 (CS-E) CS-GAGs as NSC carriers, and their ability to create endogenous niches by enriching specific trophic factors to support NSC self-renewal. We demonstrate that CS-GAG hydrogel scaffolds showed minimal swelling and degradation over a period of 15 days in vitro, absorbing only 6.5 ± 0.019% of their initial weight, and showing no significant loss of mass during this period. Trophic factors FGF-2, BDNF, and IL10 bound with high affinity to CS-GAGs, and were significantly (p < 0.05) enriched in CS-GAG hydrogels when compared to unsulfated hyaluronic acid (HA) hydrogels. Dissociated rat subventricular zone (SVZ) NSCs when encapsulated in CS-GAG hydrogels demonstrated ∼88.5 ± 6.1% cell viability in vitro. Finally, rat neurospheres in CS-GAG hydrogels conditioned with the mitogen FGF-2 demonstrated significantly (p < 0.05) higher self-renewal when compared to neurospheres cultured in unconditioned hydrogels. Taken together, these findings demonstrate the ability of CS-GAG based hydrogels to regulate NSC self-renewal, and facilitate growth factor enrichment locally.
Collapse
Affiliation(s)
- Lohitash Karumbaiah
- Regenerative Bioscience Center, ADS Complex, The University of Georgia , 425 River Road, Athens, Georgia 30602, United States
| | | | - Ashley C Brown
- Joint Department of Biomedical Engineering NC State University/UNC-Chapel Hill , 4204 B Engineering Building III, Raleigh, North Carolina 27695, United States
| | | | - Martha I Betancur
- Regenerative Bioscience Center, ADS Complex, The University of Georgia , 425 River Road, Athens, Georgia 30602, United States
| | | | | |
Collapse
|
22
|
Loomis KH, Kirschman JL, Bhosle S, Bellamkonda RV, Santangelo PJ. Strategies for modulating innate immune activation and protein production of in vitro transcribed mRNAs. J Mater Chem B 2015; 4:1619-1632. [PMID: 32263015 DOI: 10.1039/c5tb01753j] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Synthetic mRNA has recently shown great potential as a tool for genetic introduction of proteins. Its utility as a gene carrier has been demonstrated in several studies for both the introduction of therapeutic proteins and subunit vaccines. At one point, synthetic mRNA was believed to be too immunogenic and labile for pharmaceutical purposes. However, the development of several strategies have enabled mRNA technology to overcome these challenges, including incorporation of modified nucleotides, codon optimization of the coding region, incorporation of untranslated regions into the mRNA, and the use of delivery vehicles. While these approaches have been shown to enhance performance of some mRNA constructs, gene-to-gene variation and low efficiency of mRNA protein production are still significant hurdles. Further mechanistic understanding of how these strategies affect protein production and innate immune activation is needed for the widespread adoption for both therapeutic and vaccine applications. This review highlights key studies involved in the development of strategies employed to increase protein expression and control the immunogenicity of synthetic mRNA. Areas in the literature where improved understanding is needed will also be discussed.
Collapse
Affiliation(s)
- Kristin H Loomis
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, USA.
| | | | | | | | | |
Collapse
|
23
|
Shen W, Karumbaiah L, Liu X, Saxena T, Chen S, Patkar R, Bellamkonda RV, Allen MG. Extracellular matrix-based intracortical microelectrodes: Toward a microfabricated neural interface based on natural materials. Microsyst Nanoeng 2015; 1:15010. [PMID: 30498620 PMCID: PMC6258041 DOI: 10.1038/micronano.2015.10] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2015] [Revised: 05/10/2015] [Accepted: 05/15/2015] [Indexed: 05/16/2023]
Abstract
Extracellular matrix (ECM)-based implantable neural electrodes (NEs) were achieved using a microfabrication strategy on natural-substrate-based organic materials. The ECM-based design minimized the introduction of non-natural products into the brain. Further, it rendered the implants sufficiently rigid for penetration into the target brain region and allowed them subsequently to soften to match the elastic modulus of brain tissue upon exposure to physiological conditions, thereby reducing inflammatory strain fields in the tissue. Preliminary studies suggested that ECM-NEs produce a reduced inflammatory response compared with inorganic rigid and flexible approaches. In vivo intracortical recordings from the rat motor cortex illustrate one mode of use for these ECM-NEs.
Collapse
Affiliation(s)
- Wen Shen
- Institute for Electronics and Nanotechnology, Georgia Institute of Technology, Atlanta, GA 30332, USA
- Krishna P. Singh Center for Nanotechnology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Lohitash Karumbaiah
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory School of Medicine, Atlanta, GA 30332, USA
| | - Xi Liu
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Tarun Saxena
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory School of Medicine, Atlanta, GA 30332, USA
| | - Shuodan Chen
- Institute for Electronics and Nanotechnology, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Radhika Patkar
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory School of Medicine, Atlanta, GA 30332, USA
| | - Ravi V. Bellamkonda
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory School of Medicine, Atlanta, GA 30332, USA
| | - Mark G. Allen
- Institute for Electronics and Nanotechnology, Georgia Institute of Technology, Atlanta, GA 30332, USA
- Krishna P. Singh Center for Nanotechnology, University of Pennsylvania, Philadelphia, PA 19104, USA
| |
Collapse
|
24
|
Lee S, Valmikinathan CM, Byun J, Kim S, Lee G, Mokarram N, Pai SB, Um E, Bellamkonda RV, Yoon YS. Enhanced therapeutic neovascularization by CD31-expressing cells and embryonic stem cell-derived endothelial cells engineered with chitosan hydrogel containing VEGF-releasing microtubes. Biomaterials 2015; 63:158-67. [PMID: 26102992 DOI: 10.1016/j.biomaterials.2015.06.009] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Revised: 06/07/2015] [Accepted: 06/10/2015] [Indexed: 12/14/2022]
Abstract
Various stem cells and their progeny have been used therapeutically for vascular regeneration. One of the major hurdles for cell-based therapy is low cell retention in vivo, and to improve cell survival several biomaterials have been used to encapsulate cells before transplantation. Vascular regeneration involves new blood vessel formation which consists of two processes, vasculogenesis and angiogenesis. While embryonic stem cell (ESC)-derived endothelial cells (ESC-ECs) have clearer vasculogenic potency, adult cells exert their effects mainly through paracrine angiogenic activities. While these two cells have seemingly complementary advantages, there have not been any studies to date combining these two cell types for vascular regeneration. We have developed a novel chitosan-based hydrogel construct that encapsulates both CD31-expressing BM-mononuclear cells (BM-CD31(+) cells) and ESC-ECs, and is loaded with VEGF-releasing microtubes. This cell construct showed high cell survival and minimal cytotoxicity in vitro. When implanted into a mouse model of hindlimb ischemia, it induced robust cell retention, neovascularization through vasculogenesis and angiogenesis, and efficiently induced recovery of blood flow in ischemic hindlimbs. This chitosan-based hydrogel encapsulating mixed adult and embryonic cell derivatives and containing VEGF can serve as a novel platform for treating various cardiovascular diseases.
Collapse
Affiliation(s)
- Sangho Lee
- Department of Medicine, Division of Cardiology, Emory University School of Medicine, 101 Woodruff Circle, Atlanta, GA 30322, USA
| | - Chandra M Valmikinathan
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, 313 Ferst Drive, Atlanta, GA 30332, USA
| | - Jaemin Byun
- Department of Medicine, Division of Cardiology, Emory University School of Medicine, 101 Woodruff Circle, Atlanta, GA 30322, USA
| | - Sangsung Kim
- Department of Medicine, Division of Cardiology, Emory University School of Medicine, 101 Woodruff Circle, Atlanta, GA 30322, USA
| | - Geehee Lee
- Department of Medicine, Division of Cardiology, Emory University School of Medicine, 101 Woodruff Circle, Atlanta, GA 30322, USA
| | - Nassir Mokarram
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, 313 Ferst Drive, Atlanta, GA 30332, USA
| | - S Balakrishna Pai
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, 313 Ferst Drive, Atlanta, GA 30332, USA
| | - Elisa Um
- Department of Medicine, Division of Cardiology, Emory University School of Medicine, 101 Woodruff Circle, Atlanta, GA 30322, USA
| | - Ravi V Bellamkonda
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, 313 Ferst Drive, Atlanta, GA 30332, USA
| | - Young-sup Yoon
- Department of Medicine, Division of Cardiology, Emory University School of Medicine, 101 Woodruff Circle, Atlanta, GA 30322, USA; Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, 313 Ferst Drive, Atlanta, GA 30332, USA; Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul 120-752, South Korea.
| |
Collapse
|
25
|
Rangavajla G, Mokarram N, Masoodzadehgan N, Pai SB, Bellamkonda RV. Noninvasive imaging of peripheral nerves. Cells Tissues Organs 2015; 200:69-77. [PMID: 25766202 DOI: 10.1159/000369451] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/28/2014] [Indexed: 12/19/2022] Open
Abstract
Recent developments in the field of peripheral nerve imaging extend the capabilities of imaging modalities to assist in the diagnosis and treatment of patients with peripheral nerve maladies. Methods such as magnetic resonance imaging (MRI) and its derivative diffusion tensor imaging (DTI), ultrasound (US) and positron emission tomography (PET) are capable of assessing nerve structure and function following injury and relating the state of the nerve to electrophysiological and histological analysis. Of the imaging methods surveyed here, each offered unique and interesting advantages related to the field. MRI offered the opportunity to visualize immune activity on the injured nerve throughout the course of the regeneration process, and DTI offered numerical characterization of the injury and the ability to develop statistical bases for diagnosing injury. US extends imaging to the treatment phase by enabling more precise analgesic applications following surgery, and PET represents a novel method of assessing nerve injury through analysis of relative metabolism rates in injured and healthy tissue. Exciting new possibilities to enhance and extend the abilities of imaging methods are also discussed, including innovative contrast agents, some of which enable multimodal imaging approaches and present opportunities for treatment application.
Collapse
|
26
|
Saxena T, Loomis KH, Pai SB, Karumbaiah L, Gaupp E, Patil K, Patkar R, Bellamkonda RV. Nanocarrier-mediated inhibition of macrophage migration inhibitory factor attenuates secondary injury after spinal cord injury. ACS Nano 2015; 9:1492-505. [PMID: 25587936 DOI: 10.1021/nn505980z] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Spinal cord injury (SCI) can lead to permanent motor and sensory deficits. Following the initial traumatic insult, secondary injury mechanisms characterized by persistent heightened inflammation are initiated and lead to continued and pervasive cell death and tissue damage. Anti-inflammatory drugs such as methylprednisolone (MP) used clinically have ambiguous benefits with debilitating side effects. Typically, these drugs are administered systemically at high doses, resulting in toxicity and paradoxically increased inflammation. Furthermore, these drugs have a small time window postinjury (few hours) during which they need to be infused to be effective. As an alternative to MP, we investigated the effect of a small molecule inhibitor (Chicago sky blue, CSB) of macrophage migration inhibitory factor (MIF) for treating SCI. The pleiotropic cytokine MIF is known to contribute to upregulation of several pro-inflammatory cytokines in various disease and injury states. In vitro, CSB administration alleviated endotoxin-mediated inflammation in primary microglia and macrophages. Nanocarriers such as liposomes can potentially alleviate systemic side effects of high-dose therapy by enabling site-specific drug delivery to the spinal cord. However, the therapeutic window of 100 nm scale nanoparticle localization to the spinal cord after contusion injury is not fully known. Thus, we first investigated the ability of nanocarriers of different sizes to localize to the injured spinal cord up to 2 weeks postinjury. Results from the study showed that nanocarriers as large as 200 nm in diameter could extravasate into the injured spinal cord up to 96 h postinjury. We then formulated nanocarriers (liposomes) encapsulating CSB and administered them intravenously 48 h postinjury, within the previously determined 96 h therapeutic window. In vivo, in this clinically relevant contusion injury model in rats, CSB administration led to preservation of vascular and white matter integrity, improved wound healing, and an increase in levels of arginase and other transcripts indicative of a resolution phase of wound healing. This study demonstrates the potential of MIF inhibition in SCI and the utility of nanocarrier-mediated drug delivery selectively to the injured cord.
Collapse
Affiliation(s)
- Tarun Saxena
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine , Atlanta, Georgia 30332, United States
| | | | | | | | | | | | | | | |
Collapse
|
27
|
Abstract
Stem cells are a promising source for cell replacement therapy for several degenerative conditions. However, a number of limitations such as low cell survival, uncontrolled and/or low differentiation, induction of host immune response, and the risk of teratoma formation remain as challenges. In this review, we explore the utility of hydrogels as carriers for stem cell delivery and their potential to overcome some of the current limitations in stem cell therapy. We focus on in situ gelling hydrogels, and also discuss other strategies to modulate the immune response to promote controlled stem cell differentiation. Immunomodulatory hydrogels and gels designed to promote cell survival and integration into the host site will likely have a significant effect on enhancing the efficacy of stem cell transplantation as a therapy for debilitating degenerative diseases.
Collapse
|
28
|
Gutowski SM, Shoemaker JT, Templeman KL, Wei Y, Latour RA, Bellamkonda RV, LaPlaca MC, García AJ. Protease-degradable PEG-maleimide coating with on-demand release of IL-1Ra to improve tissue response to neural electrodes. Biomaterials 2015; 44:55-70. [PMID: 25617126 DOI: 10.1016/j.biomaterials.2014.12.009] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2014] [Revised: 12/01/2014] [Accepted: 12/16/2014] [Indexed: 01/18/2023]
Abstract
Neural electrodes are an important part of brain-machine interface devices that can restore functionality to patients with sensory and movement disorders. Chronically implanted neural electrodes induce an unfavorable tissue response which includes inflammation, scar formation, and neuronal cell death, eventually causing loss of electrode function. We developed a poly(ethylene glycol) hydrogel coating for neural electrodes with non-fouling characteristics, incorporated an anti-inflammatory agent, and engineered a stimulus-responsive degradable portion for on-demand release of the anti-inflammatory agent in response to inflammatory stimuli. This coating reduces in vitro glial cell adhesion, cell spreading, and cytokine release compared to uncoated controls. We also analyzed the in vivo tissue response using immunohistochemistry and microarray qRT-PCR. Although no differences were observed among coated and uncoated electrodes for inflammatory cell markers, lower IgG penetration into the tissue around PEG+IL-1Ra coated electrodes indicates an improvement in blood-brain barrier integrity. Gene expression analysis showed higher expression of IL-6 and MMP-2 around PEG+IL-1Ra samples, as well as an increase in CNTF expression, an important marker for neuronal survival. Importantly, increased neuronal survival around coated electrodes compared to uncoated controls was observed. Collectively, these results indicate promising findings for an engineered coating to increase neuronal survival and improve tissue response around implanted neural electrodes.
Collapse
Affiliation(s)
- Stacie M Gutowski
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA; Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
| | - James T Shoemaker
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA; Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
| | - Kellie L Templeman
- Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA; Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Yang Wei
- Department of Bioengineering, Clemson University, Clemson, SC, USA
| | - Robert A Latour
- Department of Bioengineering, Clemson University, Clemson, SC, USA
| | - Ravi V Bellamkonda
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA; Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
| | - Michelle C LaPlaca
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA; Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
| | - Andrés J García
- Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA; Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA.
| |
Collapse
|
29
|
Srinivasan A, Tahilramani M, Bentley JT, Gore RK, Millard DC, Mukhatyar VJ, Joseph A, Haque AS, Stanley GB, English AW, Bellamkonda RV. Microchannel-based regenerative scaffold for chronic peripheral nerve interfacing in amputees. Biomaterials 2014; 41:151-65. [PMID: 25522974 DOI: 10.1016/j.biomaterials.2014.11.035] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Revised: 10/25/2014] [Accepted: 11/07/2014] [Indexed: 12/17/2022]
Abstract
Neurally controlled prosthetics that cosmetically and functionally mimic amputated limbs remain a clinical need because state of the art neural prosthetics only provide a fraction of a natural limb's functionality. Here, we report on the fabrication and capability of polydimethylsiloxane (PDMS) and epoxy-based SU-8 photoresist microchannel scaffolds to serve as viable constructs for peripheral nerve interfacing through in vitro and in vivo studies in a sciatic nerve amputee model where the nerve lacks distal reinnervation targets. These studies showed microchannels with 100 μm × 100 μm cross-sectional areas support and direct the regeneration/migration of axons, Schwann cells, and fibroblasts through the microchannels with space available for future maturation of the axons. Investigation of the nerve in the distal segment, past the scaffold, showed a high degree of organization, adoption of the microchannel architecture forming 'microchannel fascicles', reformation of endoneurial tubes and axon myelination, and a lack of aberrant and unorganized growth that might be characteristic of neuroma formation. Separate chronic terminal in vivo electrophysiology studies utilizing the microchannel scaffolds with permanently integrated microwire electrodes were conducted to evaluate interfacing capabilities. In all devices a variety of spontaneous, sensory evoked and electrically evoked single and multi-unit action potentials were recorded after five months of implantation. Together, these findings suggest that microchannel scaffolds are well suited for chronic implantation and peripheral nerve interfacing to promote organized nerve regeneration that lends itself well to stable interfaces. Thus this study establishes the basis for the advanced fabrication of large-electrode count, wireless microchannel devices that are an important step towards highly functional, bi-directional peripheral nerve interfaces.
Collapse
Affiliation(s)
- Akhil Srinivasan
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA 30332, USA
| | - Mayank Tahilramani
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA 30332, USA
| | - John T Bentley
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA 30332, USA
| | - Russell K Gore
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA 30332, USA; Department of Neurology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Daniel C Millard
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA 30332, USA
| | - Vivek J Mukhatyar
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA 30332, USA
| | - Anish Joseph
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA 30332, USA
| | - Adel S Haque
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA 30332, USA
| | - Garrett B Stanley
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA 30332, USA
| | - Arthur W English
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Ravi V Bellamkonda
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA 30332, USA.
| |
Collapse
|
30
|
Sawyer AJ, Tian W, Saucier-Sawyer JK, Rizk PJ, Saltzman WM, Bellamkonda RV, Kyriakides TR. The effect of inflammatory cell-derived MCP-1 loss on neuronal survival during chronic neuroinflammation. Biomaterials 2014; 35:6698-706. [PMID: 24881026 DOI: 10.1016/j.biomaterials.2014.05.008] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Accepted: 05/01/2014] [Indexed: 01/22/2023]
Abstract
Intracranial implants elicit neurodegeneration via the foreign body response (FBR) that includes BBB leakage, macrophage/microglia accumulation, and reactive astrogliosis, in addition to neuronal degradation that limit their useful lifespan. Previously, monocyte chemoattractant protein 1 (MCP-1, also CCL2), which plays an important role in monocyte recruitment and propagation of inflammation, was shown to be critical for various aspects of the FBR in a tissue-specific manner. However, participation of MCP-1 in the brain FBR has not been evaluated. Here we examined the FBR to intracortical silicon implants in MCP-1 KO mice at 1, 2, and 8 weeks after implantation. MCP-1 KO mice had a diminished FBR compared to WT mice, characterized by reductions in BBB leakage, macrophage/microglia accumulation, and astrogliosis, and an increased neuronal density. Moreover, pharmacological inhibition of MCP-1 in implant-bearing WT mice maintained the increased neuronal density. To elucidate the relative contribution of microglia and macrophages, bone marrow chimeras were generated between MCP-1 KO and WT mice. Increased neuronal density was observed only in MCP-1 knockout mice transplanted with MCP-1 knockout marrow, which indicates that resident cells in the brain are major contributors. We hypothesized that these improvements are the result of a phenotypic switch of the macrophages/microglia polarization state, which we confirmed using PCR for common activation markers. Our observations suggest that MCP-1 influences neuronal loss, which is integral to the progression of neurological disorders like Alzheimer's and Parkinson disease, via BBB leakage and macrophage polarization.
Collapse
Affiliation(s)
- Andrew J Sawyer
- Department of Pathology, Yale School of Medicine, 310 Cedar Street LH 108, New Haven, CT 06520-8023, USA
| | - Weiming Tian
- Bio-X Center, School of Life Science and Technology, Harbin Institute of Technology, Harbin 150080, PR China
| | | | - Paul J Rizk
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - W Mark Saltzman
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - Ravi V Bellamkonda
- Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Themis R Kyriakides
- Department of Pathology, Yale School of Medicine, 310 Cedar Street LH 108, New Haven, CT 06520-8023, USA; Department of Biomedical Engineering, Yale University, New Haven, CT, USA.
| |
Collapse
|
31
|
Jain A, Betancur M, Patel GD, Valmikinathan CM, Mukhatyar VJ, Vakharia A, Pai SB, Brahma B, MacDonald TJ, Bellamkonda RV. Guiding intracortical brain tumour cells to an extracortical cytotoxic hydrogel using aligned polymeric nanofibres. Nat Mater 2014; 13:308-16. [PMID: 24531400 DOI: 10.1038/nmat3878] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Accepted: 01/02/2014] [Indexed: 05/19/2023]
Abstract
Glioblastoma multiforme is an aggressive, invasive brain tumour with a poor survival rate. Available treatments are ineffective and some tumours remain inoperable because of their size or location. The tumours are known to invade and migrate along white matter tracts and blood vessels. Here, we exploit this characteristic of glioblastoma multiforme by engineering aligned polycaprolactone (PCL)-based nanofibres for tumour cells to invade and, hence, guide cells away from the primary tumour site to an extracortical location. This extracortial sink is a cyclopamine drug-conjugated, collagen-based hydrogel. When aligned PCL-nanofibre films in a PCL/polyurethane carrier conduit were inserted in the vicinity of an intracortical human U87MG glioblastoma xenograft, a significant number of human glioblastoma cells migrated along the aligned nanofibre films and underwent apoptosis in the extracortical hydrogel. Tumour volume in the brain was significantly lower following insertion of aligned nanofibre implants compared with the application of smooth fibres or no implants.
Collapse
Affiliation(s)
- Anjana Jain
- 1] Neurological Biomaterials and Cancer Therapeutics Laboratory, Wallace H. Coulter Department of Biomedical Engineering Georgia Institute of Technology/Emory University School of Medicine, 313 Ferst Drive, Atlanta Georgia 30332 USA [2]
| | - Martha Betancur
- Neurological Biomaterials and Cancer Therapeutics Laboratory, Wallace H. Coulter Department of Biomedical Engineering Georgia Institute of Technology/Emory University School of Medicine, 313 Ferst Drive, Atlanta Georgia 30332 USA
| | - Gaurangkumar D Patel
- Neurological Biomaterials and Cancer Therapeutics Laboratory, Wallace H. Coulter Department of Biomedical Engineering Georgia Institute of Technology/Emory University School of Medicine, 313 Ferst Drive, Atlanta Georgia 30332 USA
| | - Chandra M Valmikinathan
- Neurological Biomaterials and Cancer Therapeutics Laboratory, Wallace H. Coulter Department of Biomedical Engineering Georgia Institute of Technology/Emory University School of Medicine, 313 Ferst Drive, Atlanta Georgia 30332 USA
| | - Vivek J Mukhatyar
- Neurological Biomaterials and Cancer Therapeutics Laboratory, Wallace H. Coulter Department of Biomedical Engineering Georgia Institute of Technology/Emory University School of Medicine, 313 Ferst Drive, Atlanta Georgia 30332 USA
| | - Ajit Vakharia
- Neurological Biomaterials and Cancer Therapeutics Laboratory, Wallace H. Coulter Department of Biomedical Engineering Georgia Institute of Technology/Emory University School of Medicine, 313 Ferst Drive, Atlanta Georgia 30332 USA
| | - S Balakrishna Pai
- Neurological Biomaterials and Cancer Therapeutics Laboratory, Wallace H. Coulter Department of Biomedical Engineering Georgia Institute of Technology/Emory University School of Medicine, 313 Ferst Drive, Atlanta Georgia 30332 USA
| | - Barunashish Brahma
- Department of Neurosurgery Children's Health Care of Atlanta Georgia 30342 USA
| | - Tobey J MacDonald
- Department of Pediatrics, Aflac Cancer And Blood Disorders Center Emory University School of Medicine Atlanta, Georgia 30322 USA
| | - Ravi V Bellamkonda
- Neurological Biomaterials and Cancer Therapeutics Laboratory, Wallace H. Coulter Department of Biomedical Engineering Georgia Institute of Technology/Emory University School of Medicine, 313 Ferst Drive, Atlanta Georgia 30332 USA
| |
Collapse
|
32
|
Abstract
An immune response involves the action of all types of macrophages, classically activated subtype (M1) in the early inflammatory phase and regulatory and wound-healing subtypes (M2) in the resolution phase. The remarkable plasticity of macrophages makes them an interesting target in the context of immunomodulation. Here, we reviewed the current state of understanding regarding the role that different phenotypes of macrophages and monocytes play following injury and during the course of remodeling in different tissue types. Moreover, we explored recent designs of macrophage modulatory biomaterials for tissue engineering and regenerative medicine applications.
Collapse
Affiliation(s)
- Nassir Mokarram
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | | |
Collapse
|
33
|
Karumbaiah L, Saxena T, Carlson D, Patil K, Patkar R, Gaupp EA, Betancur M, Stanley GB, Carin L, Bellamkonda RV. Relationship between intracortical electrode design and chronic recording function. Biomaterials 2013; 34:8061-74. [DOI: 10.1016/j.biomaterials.2013.07.016] [Citation(s) in RCA: 186] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Accepted: 07/03/2013] [Indexed: 12/16/2022]
|
34
|
Saxena T, Karumbaiah L, Gaupp EA, Patkar R, Patil K, Betancur M, Stanley GB, Bellamkonda RV. The impact of chronic blood–brain barrier breach on intracortical electrode function. Biomaterials 2013; 34:4703-13. [DOI: 10.1016/j.biomaterials.2013.03.007] [Citation(s) in RCA: 157] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2013] [Accepted: 03/03/2013] [Indexed: 02/01/2023]
|
35
|
Gutowski SM, Templeman KL, South AB, Gaulding JC, Shoemaker JT, LaPlaca MC, Bellamkonda RV, Lyon LA, García AJ. Host response to microgel coatings on neural electrodes implanted in the brain. J Biomed Mater Res A 2013; 102:1486-99. [PMID: 23666919 DOI: 10.1002/jbm.a.34799] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Revised: 04/15/2013] [Accepted: 05/03/2013] [Indexed: 11/10/2022]
Abstract
The performance of neural electrodes implanted in the brain is often limited by host response in the surrounding brain tissue, including astrocytic scar formation, neuronal cell death, and inflammation around the implant. We applied conformal microgel coatings to silicon neural electrodes and examined host responses to microgel-coated and uncoated electrodes following implantation in the rat brain. In vitro analyses demonstrated significantly reduced astrocyte and microglia adhesion to microgel-coated electrodes compared to uncoated controls. Microgel-coated and uncoated electrodes were implanted in the rat brain cortex and the extent of activated microglia and astrocytes as well as neuron density around the implant were evaluated at 1, 4, and 24 weeks postimplantation. Microgel coatings reduced astrocytic recruitment around the implant at later time points. However, microglial response indicated persistence of inflammation in the area around the electrode. Neuronal density around the implanted electrodes was also lower for both implant groups compared to the uninjured control. These results demonstrate that microgel coatings do not significantly improve host responses to implanted neural electrodes and underscore the need for further improvements in implantable materials.
Collapse
Affiliation(s)
- Stacie M Gutowski
- Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia, 30332-0363; Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Georgia, 30332-0363
| | | | | | | | | | | | | | | | | |
Collapse
|
36
|
Abramson S, Ackermann DM, Akins R, Anders R, Andersen PJ, Anderson JM, Ankrum JA, Anseth KS, Antonucci J, Atzet S, Badylak SF, Baura GD, Bellamkonda RV, Best SM, Bhumiratana S, Bianco RW, Bokros JC, Borovetz HS, Boskey AL, Brown JL, Brown BN, Brown SA, Brunski JB, Cahn F, Ritchie AC, Caplan AI, Carpenedo RL, Chilkoti A, Chung S, Cimetta E, Cleary G, Clements IP, Colas A, Coleman KP, Conway DE, Cooper SL, Costerton B, Coury AJ, Cunanan C, Curtis J, D’Amore A, DeMeo P, Desai TA, Dickens S, Domingo G, Duncan E, Eskin SG, Feigal DW, Ferreira L, Fuller J, Gallegos RP, Gawalt E, Ghosh K, Ghosn B, Gilbert TW, Glaser DE, Godier-Furnemont A, Gombotz WR, Grainger DW, Grunkemeier GL, Hacking SA, Hallab NJ, Hall-Stoodley L, Hanson SR, Haubold AD, Hauch KD, Hawkins KR, Heath DE, Helm DL, Hench LL, Hensten A, Hill RT, Hobson C, Hoerstrup SP, Hoffman AS, Horbett TA, Hubbell JA, Humayun MS, Ideker R, Ingber DE, Jain R, Jacob J, Jacobs JJ, Jacobsen N, Jin R, Johnson RJ, Karp JM, Kasper FK, Kathju S, Khademhosseini A, Kim S, King MW, Kleiner LW, Kohn J, Koschwanez HE, Kumbar SG, Kuo CK, LaFleur L, Lahti MT, Lambert B, Langer R, Laurencin CT, Lee-Parritz D, Lemons JE, Levin M, Levy RJ, Lewerenz GM, Li WJ, Lin CC, Liu F, Lowrie WG, Lu Y, Lysaght MJ, Maidhof R, Mansbridge J, Cristina M, Martins L, Martin J, Mayesh JP, McDevitt TC, McIntire LV, Merrit K, Migliaresi C, Mikos AG, Misch CE, Mitchell RN, More RB, Moss CW, Munson JM, Navarro M, Nerem RM, Ogawa R, Orgill BD, Orgill DP, Padera RF, Pandit A, Park K, Patel AS, Peck RB, Peckham PH, Peppas NA, Pereira MN, Planell J, Popat KC, Prestwich GD, Pun SH, Rabolt J, Rainbow RS, Rajab T, Ratner BD, Reichert WM, Rivard AL, Rowley AP, Ruan G, Sacks M, Sarkar D, Schaefer S, Schmidt CE, Schoen FJ, Schutte SC, Sefton MV, Shalaby SW, Shirtliff M, Simon MA, Singh M, Slack SM, Spelman FA, Starr A, Stayton PS, Steinert R, Stoodley P, Suri S, Swi Chang TM, Tandon N, Tanguay AR, Taylor MS, Teo GS, Thodeti CK, Tolkoff J, Treiser M, Tuan RS, Tucker EI, Venugopalan R, Vicari AR, Viney C, Voight JM, Vunjak-Novakovic G, Wagner WR, Wang L, Wasiluk KR, Watts DC, Weigl BH, Weiland JD, Whalen JJ, Williams DF, Williams RL, Wilson JT, Wilson CG, Winter J, Wolf MF, Wright JC, Yager P, Zhao W. Contributors. Biomater Sci 2013. [DOI: 10.1016/b978-0-08-087780-8.00150-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
37
|
Abstract
Brain tumor invasion leads to recurrence and resistance to treatment. Glioma cells invade in distinct patterns, possibly determined by microenvironmental cues including chemokines, structural heterogeneity, and fluid flow. We hypothesized that flow originating from pressure differentials between the brain and tumor is active in glioma invasion. Using in vitro models, we show that interstitial flow promotes cell invasion in multiple glioma cell lines. Flow effects were CXCR4-dependent, because they were abrogated by CXCR4 inhibition. Furthermore, CXCR4 was activated in response to flow, which could be responsible for enhanced cell motility. Flow was seen to enhance cell polarization in the flow direction, and this flow-induced polarization could be blocked by CXCR4 inhibition or CXCL12 oversaturation in the matrix. Furthermore, using live imaging techniques in a three-dimensional flow chamber, there were more cells migrating and more cells migrating in the direction of flow. This study shows that interstitial flow is an active regulator of glioma invasion. The new mechanisms of glioma invasion that we identify here-namely, interstitial flow-enhanced motility, activation of CXCR4, and CXCL12-driven autologous chemotaxis-are significant in therapy to prevent or treat brain cancer invasion. Current treatment strategies can lead to edema and altered flow in the brain, and one popular experimental treatment in clinical trials, convection enhanced delivery, involves enhancement of flow in and around the tumor. A better understanding of how interstitial flow at the tumor margin can alter chemokine distributions, cell motility, and directed invasion offers a better understanding of treatment failure. .
Collapse
Affiliation(s)
- Jennifer M Munson
- Laboratory of Lymphatic and Cancer Bioengineering, Institute of Bioengineering and Swiss Institute for Experimental Cancer Research, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
| | | | | |
Collapse
|
38
|
Clements IP, Mukhatyar VJ, Srinivasan A, Bentley JT, Andreasen DS, Bellamkonda RV. Regenerative scaffold electrodes for peripheral nerve interfacing. IEEE Trans Neural Syst Rehabil Eng 2012; 21:554-66. [PMID: 23033438 DOI: 10.1109/tnsre.2012.2217352] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Advances in neural interfacing technology are required to enable natural, thought-driven control of a prosthetic limb. Here, we describe a regenerative electrode design in which a polymer-based thin-film electrode array is integrated within a thin-film sheet of aligned nanofibers, such that axons regenerating from a transected peripheral nerve are topographically guided across the electrode recording sites. Cultures of dorsal root ganglia were used to explore design parameters leading to cellular migration and neurite extension across the nanofiber/electrode array boundary. Regenerative scaffold electrodes (RSEs) were subsequently fabricated and implanted across rat tibial nerve gaps to evaluate device recording capabilities and influence on nerve regeneration. In 20 of these animals, regeneration was compared between a conventional nerve gap model and an amputation model. Characteristic shaping of regenerated nerve morphology around the embedded electrode array was observed in both groups, and regenerated axon profile counts were similar at the eight week end point. Implanted RSEs recorded evoked neural activity in all of these cases, and also in separate implantations lasting up to five months. These results demonstrate that nanofiber-based topographic cues within a regenerative electrode can influence nerve regeneration, to the potential benefit of a peripheral nerve interface suitable for limb amputees.
Collapse
Affiliation(s)
- Isaac P Clements
- Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332 USA.
| | | | | | | | | | | |
Collapse
|
39
|
Munson JM, Fried L, Rowson SA, Bonner MY, Karumbaiah L, Diaz B, Courtneidge SA, Knaus UG, Brat DJ, Arbiser JL, Bellamkonda RV. Anti-invasive adjuvant therapy with imipramine blue enhances chemotherapeutic efficacy against glioma. Sci Transl Med 2012; 4:127ra36. [PMID: 22461640 DOI: 10.1126/scitranslmed.3003016] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The invasive nature of glioblastoma (GBM) represents a major clinical challenge contributing to poor outcomes. Invasion of GBM into healthy tissue restricts chemotherapeutic access and complicates surgical resection. Here, we test the hypothesis that an effective anti-invasive agent can "contain" GBM and increase the efficacy of chemotherapy. We report a new anti-invasive small molecule, Imipramine Blue (IB), which inhibits invasion of glioma in vitro when tested against several models. IB inhibits NADPH (reduced form of nicotinamide adenine dinucleotide phosphate) oxidase-mediated reactive oxygen species generation and alters expression of actin regulatory elements. In vivo, liposomal IB (nano-IB) halts invasion of glioma, leading to a more compact tumor in an aggressively invasive RT2 syngeneic astrocytoma rodent model. When nano-IB therapy was followed by liposomal doxorubicin (nano-DXR) chemotherapy, the combination therapy prolonged survival compared to nano-IB or nano-DXR alone. Our data demonstrate that nano-IB-mediated containment of diffuse glioma enhanced the efficacy of nano-DXR chemotherapy, demonstrating the promise of an anti-invasive compound as an adjuvant treatment for glioma.
Collapse
Affiliation(s)
- Jennifer M Munson
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Uhrig BA, Clements IP, Boerckel JD, Huebsch N, Bellamkonda RV, Guldberg RE. Characterization of a composite injury model of severe lower limb bone and nerve trauma. J Tissue Eng Regen Med 2012; 8:432-41. [DOI: 10.1002/term.1537] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Revised: 02/23/2012] [Accepted: 04/18/2012] [Indexed: 11/11/2022]
Affiliation(s)
- Brent A. Uhrig
- Parker H. Petit Institute for Bioengineering and Bioscience, George W. Woodruff School of Mechanical Engineering; Georgia Institute of Technology; Atlanta GA USA
| | - Isaac P. Clements
- Wallace H. Coulter Department of Biomedical Engineering; Georgia Institute of Technology and Emory University; Atlanta GA USA
| | - Joel D. Boerckel
- Parker H. Petit Institute for Bioengineering and Bioscience, George W. Woodruff School of Mechanical Engineering; Georgia Institute of Technology; Atlanta GA USA
| | - Nathaniel Huebsch
- Harvard University School of Engineering and Applied Sciences, Harvard-MIT Division of Health Sciences and Technology; Wyss Institute of Biologically Inspired Engineering; Cambridge MA USA
| | - Ravi V. Bellamkonda
- Wallace H. Coulter Department of Biomedical Engineering; Georgia Institute of Technology and Emory University; Atlanta GA USA
| | - Robert E. Guldberg
- Parker H. Petit Institute for Bioengineering and Bioscience, George W. Woodruff School of Mechanical Engineering; Georgia Institute of Technology; Atlanta GA USA
| |
Collapse
|
41
|
Karumbaiah L, Norman SE, Rajan NB, Anand S, Saxena T, Betancur M, Patkar R, Bellamkonda RV. The upregulation of specific interleukin (IL) receptor antagonists and paradoxical enhancement of neuronal apoptosis due to electrode induced strain and brain micromotion. Biomaterials 2012; 33:5983-96. [PMID: 22681976 DOI: 10.1016/j.biomaterials.2012.05.021] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Accepted: 05/10/2012] [Indexed: 10/28/2022]
Abstract
The high mechanical mismatch between stiffness of silicon and metal microelectrodes and soft cortical tissue, induces strain at the neural interface which likely contributes to failure of the neural interface. However, little is known about the molecular outcomes of electrode induced low-magnitude strain (1-5%) on primary astrocytes, microglia and neurons. In this study we simulated brain micromotion at the electrode-brain interface by subjecting astrocytes, microglia and primary cortical neurons to low-magnitude cyclical strain using a biaxial stretch device, and investigated the molecular outcomes of induced strain in vitro. In addition, we explored the functional consequence of astrocytic and microglial strain on neural health, when they are themselves subjected to strain. Quantitative real-time PCR array (qRT-PCR Array) analysis of stretched astrocytes and microglia showed strain specific upregulation of an Interleukin receptor antagonist - IL-36Ra (previously IL-1F5), to ≈ 1018 and ≈ 236 fold respectively. Further, IL-36Ra gene expression remained unchanged in astrocytes and microglia treated with bacterial lipopolysaccharide (LPS) indicating that the observed upregulation in stretched astrocytes and microglia is potentially strain specific. Zymogram and western blot analysis revealed that mechanically strained astrocytes and microglia upregulated matrix metalloproteinases (MMPs) 2 and 9, and other markers of reactive gliosis such as glial fibrillary acidic protein (GFAP) and neurocan when compared to controls. Primary cortical neurons when stretched with and without IL-36Ra, showed a ≈ 400 fold downregulation of tumor necrosis factor receptor superfamily, member 11b (TNFRSF11b). Significant upregulation of members of the caspase cysteine proteinase family and other pro-apoptotic genes was also observed in the presence of IL-36Ra than in the absence of IL-36Ra. Adult rats when implanted with microwire electrodes showed upregulation of IL-36Ra (≈ 20 fold) and IL-1Ra (≈ 1500 fold) 3 days post-implantation (3 DPI), corroborating in vitro results, although these transcripts were drastically down regulated by ≈ 20 fold and ≈ 1488 fold relative to expression levels 3 DPI, at the end of 12 weeks post-implantation (12 WPI). These results demonstrate that IL receptor antagonists may be negatively contributing to neuronal health at acute time-points post-electrode implantation.
Collapse
Affiliation(s)
- Lohitash Karumbaiah
- Wallace H. Coulter Department of Biomedical Engineering at Georgia Institute of Technology and Emory University School of Medicine, Atlanta, 313 Ferst Drive, GA 30332-0535, USA
| | | | | | | | | | | | | | | |
Collapse
|
42
|
Valmikinathan CM, Mukhatyar VJ, Jain A, Karumbaiah L, Dasari M, Bellamkonda RV. Photocrosslinkable chitosan based hydrogels for neural tissue engineering. Soft Matter 2012; 8:1964-1976. [PMID: 29805470 PMCID: PMC5969809 DOI: 10.1039/c1sm06629c] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Hydrogel based scaffolds for neural tissue engineering can provide appropriate physico-chemical and mechanical properties to support neurite extension and facilitate transplantation of cells by acting as 'cell delivery vehicles'. Specifically, in situ gelling systems such as photocrosslinkable hydrogels can potentially conformally fill irregular neural tissue defects and serve as stem cell delivery systems. Here, we report the development of a novel chitosan based photocrosslinkable hydrogel system with tunable mechanical properties and degradation rates. A two-step synthesis of amino-ethyl methacrylate derivitized, degradable, photocrosslinkable chitosan hydrogels is described. When human mesenchymal stem cells were cultured in photocrosslinkable chitosan hydrogels, negligible cytotoxicity was observed. Photocrosslinkable chitosan hydrogels facilitated enhanced neurite differentiation from primary cortical neurons and enhanced neurite extension from dorsal root ganglia (DRG) as compared to agarose based hydrogels with similar storage moduli. Neural stem cells (NSCs) cultured within photocrosslinkable chitosan hydrogels facilitated differentiation into tubulin positive neurons and astrocytes. These data demonstrate the potential of photocrosslinked chitosan hydrogels, and contribute to an increasing repertoire of hydrogels designed for neural tissue engineering.
Collapse
Affiliation(s)
- Chandra M. Valmikinathan
- Neurological Biomaterials and Cancer Therapeutics Laboratory, USA
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, 3108, UA Whitaker Building, 313 Ferst Drive, Atlanta, Georgia, 30332-0535, USA
| | - Vivek J. Mukhatyar
- Neurological Biomaterials and Cancer Therapeutics Laboratory, USA
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, 3108, UA Whitaker Building, 313 Ferst Drive, Atlanta, Georgia, 30332-0535, USA
| | - Anjana Jain
- Neurological Biomaterials and Cancer Therapeutics Laboratory, USA
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, 3108, UA Whitaker Building, 313 Ferst Drive, Atlanta, Georgia, 30332-0535, USA
| | - Lohitash Karumbaiah
- Neurological Biomaterials and Cancer Therapeutics Laboratory, USA
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, 3108, UA Whitaker Building, 313 Ferst Drive, Atlanta, Georgia, 30332-0535, USA
| | - Madhuri Dasari
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, 3108, UA Whitaker Building, 313 Ferst Drive, Atlanta, Georgia, 30332-0535, USA
| | - Ravi V. Bellamkonda
- Neurological Biomaterials and Cancer Therapeutics Laboratory, USA
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, 3108, UA Whitaker Building, 313 Ferst Drive, Atlanta, Georgia, 30332-0535, USA
- ; Fax: +1 404 385 5044; Tel: +1 404 385 5038
| |
Collapse
|
43
|
Affiliation(s)
- Shyam Aravamudhan
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, Atlanta, Georgia
| | - Ravi V. Bellamkonda
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, Atlanta, Georgia
| |
Collapse
|
44
|
Abstract
One of the grand challenges in neuroengineering is to stimulate regeneration after central nervous system (CNS) or peripheral nervous system (PNS) injury to restore function. The state of the art today is that PNS injuries heal to a limited extent, whereas CNS injuries are largely intractable to regeneration. In this context, we examine the underlying biochemical and cellular constraints on endogenous healing of neural tissues. Identification and characterization of endogenous "rate-limiting" processes that constrain regeneration would allow one to craft solutions to overcome critical impediments for accelerated healing. It is increasingly evident that biochemical pathways triggered by the nature and duration of injury-triggered inflammatory response may determine the endogenous constraints and subsequently determine regenerative fate. In this paper, critical endogenous constraints of PNS and CNS regeneration are identified, and the effects of modulating the phenotypes of immune cells on neuronal regeneration are discussed.
Collapse
Affiliation(s)
- Nassir Mokarram
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA.
| | | |
Collapse
|
45
|
Agarwal A, Mackey MA, El-Sayed MA, Bellamkonda RV. Remote triggered release of doxorubicin in tumors by synergistic application of thermosensitive liposomes and gold nanorods. ACS Nano 2011; 5:4919-26. [PMID: 21591812 DOI: 10.1021/nn201010q] [Citation(s) in RCA: 168] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Delivery of chemotherapeutic agents after encapsulation in nanocarriers such as liposomes diminishes side-effects, as PEGylated nanocarrier pharmacokinetics decrease dosing to healthy tissues and accumulate in tumors due to the enhanced permeability and retention effect. Once in the tumor, however, dosing of the chemotherapeutic to tumor cells is limited potentially by the rate of release from the carriers and the size-constrained, poor diffusivity of nanocarriers in tumor interstitium. Here, we report the design and fabrication of a thermosensitive liposomal nanocarrier that maintains its encapsulation stability with a high concentration of doxorubicin payload, thereby minimizing "leak" and attendant toxicity. When used synergistically with PEGylated gold nanorods and near-infrared stimulation, remote triggered release of doxorubicin from thermosensitive liposomes was achieved in a mouse tumor model of human glioblastoma (U87), resulting in a significant increase in efficacy when compared to nontriggered or nonthermosensitive PEGylated liposomes. This enhancement in efficacy is attributed to increase in tumor-site apoptosis, as was evident from noninvasive apoptosis imaging using Annexin-Vivo 750 probe. This strategy affords remotely triggered control of tumor dosing of nanocarrier-encapsulated doxorubicin without sacrificing the ability to differentially dose drugs to tumors via the enhanced permeation and retention effect.
Collapse
Affiliation(s)
- Abhiruchi Agarwal
- Neurological Biomaterials and Cancer Therapeutics Laboratory, Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | | | | | | |
Collapse
|
46
|
Kolachala VL, Berg EE, Shams S, Mukhatyar V, Sueblinvong V, Bellamkonda RV, Johns MM. The use of lipid microtubes as a novel slow-release delivery system for laryngeal injection. Laryngoscope 2011; 121:1237-43. [DOI: 10.1002/lary.21796] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2011] [Accepted: 02/15/2011] [Indexed: 11/10/2022]
|
47
|
Karumbaiah L, Anand S, Thazhath R, Zhong Y, McKeon RJ, Bellamkonda RV. Targeted downregulation of N-acetylgalactosamine 4-sulfate 6-O-sulfotransferase significantly mitigates chondroitin sulfate proteoglycan-mediated inhibition. Glia 2011; 59:981-96. [PMID: 21456043 DOI: 10.1002/glia.21170] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2010] [Accepted: 02/23/2011] [Indexed: 01/17/2023]
Abstract
Chondroitin sulfate-4,6 (CS-E) glycosaminoglycan (GAG) upregulation in astroglial scars is a major contributor to chondroitin sulfate proteoglycan (CSPG)-mediated inhibition [Gilbert et al. (2005) Mol Cell Neurosci 29:545–558]. However, the role of N-acetylgalactosamine 4-sulfate 6-O-sulfotransferase (GalNAc4S6ST) catalyzed sulfation of CS-E, and its contribution to CSPG-mediated inhibition of CNS regeneration remains to be fully elucidated. Here, we used in situ hybridization to show localized upregulation of GalNAc4S6ST mRNA after CNS injury. Using in vitro spot assays with immobilized CS-E, we demonstrate dose-dependent inhibition of rat embryonic day 18 (E18) cortical neurons. To determine whether selective downregulation of CS-E affected the overall inhibitory character of extracellular matrix produced by reactive astrocytes, single [against (chondroitin 4) sulfotransferase 11 (C4ST1) or GalNAc4S6ST mRNA] or double [against C4ST1 and GalNAc4S6ST mRNA] siRNA treatments were conducted and assayed using quantitative real-time polymerase chain reaction and high-performance liquid chromatography to confirm the specific downregulation of CS-4S GAG (CS-A) and CS-E. Spot and Bonhoeffer stripe assays using astrocyte-conditioned media from siRNA-treated rat astrocytes showed a significant decrease in inhibition of neuronal attachment and neurite extensions when compared with untreated and TGF-treated astrocytes. These findings reveal that selective attenuation of CS-E via siRNA targeting of GalNAc4S6ST significantly mitigates CSPG-mediated inhibition of neurons, potentially offering a novel intervention strategy for CNS injury.
Collapse
Affiliation(s)
- Lohitash Karumbaiah
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, Georgia, USA
| | | | | | | | | | | |
Collapse
|
48
|
Steed MB, Mukhatyar V, Valmikinathan C, Bellamkonda RV. Advances in bioengineered conduits for peripheral nerve regeneration. Atlas Oral Maxillofac Surg Clin North Am 2011; 19:119-130. [PMID: 21277505 DOI: 10.1016/j.cxom.2010.11.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Although resorbable NGCs have been developed for peripheral nerve grafting, there has been little published on their use as a material for trigeminal nerve repair. Advances in engineered guidance channels and modifications to the single-lumen conduit with growth-permissive substrates, ECM proteins, neurotrophic factors, and supportive Schwann or stem cells, and anisotropic placement of these within the NGC may translate from animal models to clinical human use in the future. A great deal of research is still needed to optimize the presently available NGCs, and their use in peripheral trigeminal nerve repair and regeneration remains yet to be explored. Bioengineered NGCs and additives remain promising alternatives to autogenous nerve grafting in the future. They can incorporate all of the developing strategies for peripheral nerve regeneration that develop in concert with the ever-increasing understanding of regenerative mechanisms. The use of nanomaterials also may resolve the numerous problems associated with traditional conduit limitations by better mimicking the properties of natural tissues. Since cells directly interact with nanostructured ECM proteins, the biomimetic features of anisotropic-designed nanomaterials coupled with luminal additive ECMs, neurotrophic factors, and Schwann cells may provide for great progress in peripheral nerve regeneration.
Collapse
Affiliation(s)
- Martin B Steed
- Division of Oral and Maxillofacial Surgery, Department of Surgery, Emory University School of Medicine, 1365 Clifton Road, Atlanta, GA 30322, USA.
| | | | | | | |
Collapse
|
49
|
Jain A, McKeon RJ, Brady-Kalnay SM, Bellamkonda RV. Sustained delivery of activated Rho GTPases and BDNF promotes axon growth in CSPG-rich regions following spinal cord injury. PLoS One 2011; 6:e16135. [PMID: 21283639 PMCID: PMC3026041 DOI: 10.1371/journal.pone.0016135] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2010] [Accepted: 12/14/2010] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Spinal cord injury (SCI) often results in permanent functional loss. This physical trauma leads to secondary events, such as the deposition of inhibitory chondroitin sulfate proteoglycan (CSPG) within astroglial scar tissue at the lesion. METHODOLOGY/PRINCIPAL FINDINGS We examined whether local delivery of constitutively active (CA) Rho GTPases, Cdc42 and Rac1 to the lesion site alleviated CSPG-mediated inhibition of regenerating axons. A dorsal over-hemisection lesion was created in the rat spinal cord and the resulting cavity was conformally filled with an in situ gelling hydrogel combined with lipid microtubes that slowly released constitutively active (CA) Cdc42, Rac1, or Brain-derived neurotrophic factor (BDNF). Treatment with BDNF, CA-Cdc42, or CA-Rac1 reduced the number of GFAP-positive astrocytes, as well as CSPG deposition, at the interface of the implanted hydrogel and host tissue. Neurofilament 160kDa positively stained axons traversed the glial scar extensively, entering the hydrogel-filled cavity in the treatments with BDNF and CA-Rho GTPases. The treated animals had a higher percentage of axons from the corticospinal tract that traversed the CSPG-rich regions located proximal to the lesion site. CONCLUSION Local delivery of CA-Cdc42, CA-Rac1, and BDNF may have a significant therapeutic role in overcoming CSPG-mediated regenerative failure after SCI.
Collapse
Affiliation(s)
- Anjana Jain
- Neurological Biomaterials and Therapeutics, Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, Atlanta, Georgia, United States of America
| | - Robert J. McKeon
- Department of Cell Biology, School of Medicine, Emory University, Atlanta, Georgia, United States of America
| | - Susann M. Brady-Kalnay
- Department of Molecular Biology and Microbiology and Department of Neurosciences, School of Medicine, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Ravi V. Bellamkonda
- Neurological Biomaterials and Therapeutics, Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, Atlanta, Georgia, United States of America
| |
Collapse
|
50
|
McClain MA, Clements IP, Shafer RH, Bellamkonda RV, LaPlaca MC, Allen MG. Highly-compliant, microcable neuroelectrodes fabricated from thin-film gold and PDMS. Biomed Microdevices 2011; 13:361-73. [DOI: 10.1007/s10544-010-9505-3] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|