|ognizant Communication Corporation|
The Regenerative Medicine Journal
VOLUME 16, NUMBER 10, 2008
Cell Transplantation, Vol. 16, pp. 977-986, 2008
0963-6897/08 $90.00 + 00
Copyright © 2008 Cognizant Comm. Corp.
Printed in the USA. All rights reserved.
The TIM Family of Cosignaling Receptors: Emerging Targets for the Regulation of Autoimmune Disease and Transplantation Tolerance
Wayne Truong1 and A. M. James Shapiro1,2
1The Surgical Medical Research Institute, Department of Surgery,
Faculty of Medicine, University of Alberta, Edmonton, Alberta, Canada
2Clinical Islet Transplant Program, University of Alberta, Edmonton, Alberta, Canada
Currently, lifelong immune suppression regimens are required for solid organ and cellular transplantation and carry significant increased risk of infection, malignancy, and toxicity. For non-life-saving procedures such as islet transplantation, the risk/benefit ratio of lifelong immunosuppression versus benefit from transplantation requires even more careful balance. The search for specific agents to modulate the immune system without chronic immunosuppression is important for the broad application of islet transplantation. The T-cell immunoglobulin mucin (TIM) family is a distinct group of coreceptors that are differentially expressed on TH1 and TH2 cells, and have the potential to regulate both cytotoxic and humoral immune responses. Completed murine studies demonstrate Tim pathways may be important in the regulation of tolerance to self (auto), harmless (allergic), and transplant (allo) antigen; however, the potential impact of targeting Tim coreceptors has yet to be fully explored in transplantation tolerance induction or autoimmune disease. The current review examines the impact of Tim coreceptor targeting as an emerging therapeutic option for regulating autoimmune diseases and prevention of allograft rejection.
Key words: T-cell immunoglobulin mucin (TIM); Coreceptor; Autoimmune; Tolerance; Allergy; Immune response; T-cell activation
Address correspondence to Dr. A. M. James Shapiro, M.D., Ph.D., FRCS(Eng), FRCSC, Clinical Research Chair in Transplantation (CIHR/Wyeth), Director, Clinical Islet Transplant Program, University of Alberta, Roberts Centre, 2000 College Plaza, Edmonton, Alberta, Canada T6G 2C8. Tel: (780) 407 7330; Fax: (780) 407 6933; E-mail: email@example.com
Transplants of Encapsulated Rat Choroid Plexus Cells Exert Neuroprotection in a Rodent Model of Huntington's Disease
Cesario V. Borlongan,1,2 Christopher G. Thanos,3 Steven J. M. Skinner,4 Marilyn Geaney,4 and Dwaine F. Emerich3
1Neurology/Institute of Molecular Medicine and Genetics/School
of Graduate Studies, Medical College of Georgia, Augusta, GA, USA
2Research and Affiliations Service Line, Augusta VAMC, Augusta, GA, USA
3LCT BioPharma, Inc., Providence, RI, USA
4Living Cell Technologies Limited, Auckland, New Zealand
Choroid plexus (CP) epithelial cells secrete several neurotrophic factors and have been used in transplantation studies designed to impart neuroprotection against central nervous system (CNS) trauma. In the present study, CP was isolated from adult rats, encapsulated within alginate microcapsules, and transplanted unilaterally into the rat striatum. Three days later, unilateral injections of quinolinic acid (QA; 225 nmol) were made into the ipsilateral striatum to mimic the pathology observed in Huntington's disease (HD). After surgery, animals were tested for motor function using the placement test. Rats receiving CP transplants were significantly less impaired on this test. Nissl-stained sections demonstrated that CP transplants significantly reduced the volume of the striatal lesion produced by QA. Quantitative analysis of striatal neurons further demonstrated that choline acetyltransferase-immunoreactive, but not diaphorase-positive, neurons were protected by CP transplants. These data demonstrate that transplanted CP cells can be used to protect striatal neurons from excitotoxic damage and that the pattern of neuroprotection varies across specific neuronal populations.
Key words: Choroid plexus; Transplant; Huntington's disease; Encapsulation; Alginate
Address correspondence to Cesario V. Borlongan, Department of Neurology, BI-3080, Medical College of Georgia, 1120 15th Street, Augusta, GA 30912-3200, USA. Tel: 706-733-0188, Ext. 2485; Fax: 706-721-7619; E-mail: firstname.lastname@example.org
Intravenously Administered Bone Marrow Cells Migrate to Damaged Brain Tissue and Improve Neural Function in Ischemic Rats
Jiang Wu,1,3 Zhuo Sun,1 Hong-Shuo Sun,4 Jun Wu,1 Richard D. Weisel,1 Armand Keating,2 Zhi-Hong Li,1 Zhong-Ping Feng,4 and Ren-Ke Li1
1Division of Cardiovascular Surgery, Toronto General Research
Institute and University of Toronto, Toronto, Ontario, Canada
2Division of Stem Cell and Developmental Biology, Toronto General Research Institute and University of Toronto, Toronto, Ontario, Canada
3Department of Neurology, Second Affiliated Hospital, Harbin Medical University, Harbin, China
4Department of Physiology, University of Toronto, Toronto, Ontario, Canada
Accumulated evidence suggests that bone marrow stromal cells (BMSCs) are capable of regenerating damaged tissue. This study evaluated whether intravenously (noninvasively) administered, GFP-labeled BMSCs would migrate into damaged brain tissue and improve neurological function after a stroke. Wistar rats were subjected to middle cerebral artery occlusion and reperfusion. Twenty-four hours after injury, the rats received an IV injection of culture medium or BMSCs isolated from adult Wistar rats expressing green fluorescent protein (GFP). Two hours after injury and 1, 3, and 7 days after cell transplantation, neurological function was evaluated using a neurological severity scale. On day 7, the brain scar size was determined using tetrazolium chloride staining, and the implanted cells were identified using confocal microscopy. Immunohistochemistry was used to evaluate apoptosis and angiogenesis in the ischemic region, as well as the spatial distribution of the implanted BMSCs relative to the native neural cells. Implanted BMSCs migrated throughout the territory of the middle cerebral artery by 7 days after transplantation. Most implanted cells were located in the scar area and border zone of the ischemic region, and some expressed the neuronal marker NeuN. Rats receiving BMSC transplantation exhibited reduced scar size, limited apoptosis, and enhanced angiogenic factor expression and vascular density in the ischemic region relative to the control group, as well as significant improvements in the neurological severity scores. Intravenously administrated BMSCs facilitated the structural and functional recovery of neural tissue following ischemic injury, perhaps mediated by enhanced angiogenesis.
Key words: Stromal cells; Ischemia-reperfusion injury; Neuronal tissue regeneration; Neuronal function
Address correspondence to Ren-Ke Li, M.D., Ph.D., MaRS Centre, Toronto Medical Discovery Tower, 3-702, 101 College Street, Toronto, Ontario, Canada M5G 1L7. Tel: 416-581-7492; Fax: 416-581-7493; E-mail: email@example.com
In Vivo Tracking of Human Mesenchymal Stem Cells in Experimental Stroke
Daehong Kim,1* Byoung-gi Chun,2* Yeon-Kyung Kim,2,3 Yong Hyun Lee,2,3 Cheong-Soo Park,1 Iksoo Jeon,2 Chaejoon Cheong,1 Tae-Sun Hwang,2 Hyungmin Chung,2,3 Byoung Joo Gwag,4 Kwan Soo Hong,1 and Jihwan Song2
1MRI Team, Korea Basic Science Institute, Ochang, Korea
2CHA Stem Cell Institute, Pochon CHA University College of Medicine, Seoul, Korea
3Stem Cell Therapy Institute, CHA Biotech Co., Ltd., Seoul, Korea
4Department of Pharmacology, Ajou University School of Medicine, Suwon, Gyeonggi-do, Korea
To understand the fates of human mesenchymal stem cells (hMSCs) following transplantation into a rodent model of middle cerebral artery occlusion (MCAo), magnetic resonance imaging (MRI) techniques were employed. hMSCs were labeled with ferumoxides (Feridex®)-protamine sulfate complexes, which were visualized and examined by MRI up to 10 weeks following transplantation. Migration of the transplanted cells to the infarcted area was further confirmed by histological methods. We found that the hMSCs transplanted in MCAo models possess the capacity to migrate to the infarcted area extensively in both ipsilateral and contralateral injections, exhibiting a pathotropism. We also analyzed the detailed migration patterns of transplanted hMSCs. We speculate that the extensive migratory ability of hMSCs may represent a therapeutic potential for developing efficient cell transplantation strategies in stroke.
Key words: Migration; Human mesenchymal stem cells (hMSCs); Middle cerebral artery occlusion (MCAo); Magnetic resonance imaging (MRI)
Address correspondence to Jihwan Song, D.Phil., CHA Stem Cell Institute, Pochon CHA University College of Medicine, 4th Floor Vision Bldg., 606-16 Yeoksam 1-dong, Kangnam-gu, Seoul 135-081, Republic of Korea. Tel: +82 2 3468 3393; Fax: +82 2 3468 3264; E-mail: firstname.lastname@example.org or Kwan Soo Hong, Ph.D., MR Micro-Imaging Team, Korea Basic Science Institute, 804-1 Yangcheong-ri, Ochang-myun, Cheongwon-gun, Chungcheongbuk-do 363-883, Republic of Korea. Tel: +82 43 240 5100; Fax: +82 43 240 5069; E-mail: email@example.com
*These two authors contributed to this work equally.
Recombinant AAV Viral Vectors Serotype 1, 2, and 5 Mediate Differential Gene Transfer Efficiency in Rat Striatal Fetal Grafts
Alphonse Lubansu,1,2 Laurence Abeloos,1,2 Olivier Bockstael,2 Enni Lehtonen,2 David Blum,3* Jacques Brotchi,1 Marc Levivier,1,2 and Liliane Tenenbaum1,3
1Laboratory of Experimental Neurosurgery, Hôpital Erasme,
Université Libre de Bruxelles, Brussels, Belgium
2Department of Neurosurgery, Hôpital Erasme, Université Libre de Bruxelles, Brussels, Belgium
3Research Unit in Biotherapy and Oncology, Institut de Recherche Interdisciplinaire en Biologie Humaine et Moléculaire, Université Libre de Bruxelles, Brussels, Belgium
Intrastriatal grafts of fetal ganglionic eminences (GE) can reverse symptoms of striatal lesions in animal models of Huntington's disease. On the other hand, neurotrophic factors have been shown to protect host striatal neurons from ongoing degeneration. Neurotrophic gene transfer into GE prior to grafting could combine the benefits of striatal neuron replacement and in situ delivery of neurotrophic factors. Here we evaluate the potency of recombinant adeno-associated viruses (rAAV) as vectors for gene delivery into rat embryonic (E15) GE using the eGFP reporter gene under the control of the strong cytomegalovirus (CMV) promoter. We observed a very efficient expression of the eGFP reporter gene in organotypic cultures of GE infected with rAAV serotype 1 from 4 days until at least 4 weeks postinfection. In contrast, transduction was low and absent when using serotype 2 and serotype 5 rAAV, respectively. Two months after transplantation of rAAV2/1-infected embryonic GE in adult rat striatum, more than 20% of grafted cells expressed eGFP. The majority of transduced cells in the graft were neurons as indicated by colabeling of GFP-immunoreactive cells with the NeuN marker. Our study suggests that GE transduced by rAAV-serotype 1 vectors could be an interesting tool to mediate efficient expression of a gene coding a neurotrophic factor in Huntington's disease.
Key words: Ganglionic eminence; Fetal graft; Huntington's disease; Gene transfer; Adeno-associated virus
Address correspondence to Alphonse Lubansu, M.D., Department of Neurosurgery, Hôpital Erasme, Université Libre de Bruxelles, 808 route de Lennik, B-1070 Brussels, Belgium. Tel: 32-2-555 37 68; Fax: 32-2-555 37 55; E-mail: firstname.lastname@example.org
*Present address: INSERM U815, Lille, France.
Serum-Free Medium Provides a Clinically Relevant Method to Increase Olfactory Ensheathing Cell Numbers in Olfactory Mucosa Cell Culture
Daisuke Ito,1,3 Naoki Fujita,3 Chrystelle Ibanez,1 Nobuo Sasaki,4 Robin J. M. Franklin,1,2 and Nick D. Jeffery1,2
1Department of Veterinary Medicine, University of Cambridge,
Cambridge CB3 0ES, UK
2Cambridge Centre for Brain Repair, University of Cambridge, Cambridge CB2 2PY, UK
3Laboratories of Veterinary Emergency Medicine, Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo 113-8657, Japan
4Laboratories of Veterinary Surgery, Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo 113-8657, Japan
There is much evidence to suggest that transplanted olfactory ensheathing cells may ameliorate the functional deficits associated with injuries to the nervous system, especially the spinal cord. For clinical implementation of this strategy it will be necessary to derive large numbers of these cells from an accessible and, preferably, autologous source, implying that olfactory mucosa would be ideal. Although olfactory ensheathing cells can be derived from olfactory mucosa, in routine culture conditions the proportion of these cells is unacceptably low for clinical purposes. This study compared the effect of culturing dissociated olfactory bulb and olfactory mucosa in two different media: one containing serum and one serum free. The results indicate that olfactory ensheathing cell proportion, and absolute cell numbers, is greatly increased in serum-free conditions. Further analysis suggests that serum-free medium has a differential effect on contaminating fibronectin-positive and p75-positive cells from olfactory bulb and olfactory mucosa. This study demonstrates that serum-free culture conditions provide a simple and useful means of deriving a sufficient number of olfactory ensheathing cells for transplantation and reveals a difference in biological behavior of the cells contained within olfactory bulb and olfactory mucosa.
Key words: Canine; Dog; p75; Enrichment; Purification; Olfactory bulb
Address correspondence to Nick D. Jeffery, Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES, UK. Tel: (+44) 1223 337665; Fax: (+44) 1223 337017; E-mail: email@example.com
Comparison of Successful and Unsuccessful Islet/Sertoli Cell Cotransplant Grafts in Streptozotocin-Induced Diabetic Mice
Jannette M. Dufour,1* Sarah J. Lord,2* Tatsuya Kin,2 Gina R. Rayat,2,3 Doreen E. Dixon,2 R. Chris Bleackley,4 Gregory S. Korbutt,2,3 and Ray V. Rajotte2,3,5
1Cell Biology and Biochemistry, Texas Tech University Health
Sciences Center, Lubbock, TX 79430, USA
2Surgical-Medical Research Institute, University of Alberta, Edmonton, Alberta, T6J 6J5 Canada
3Department of Surgery, University of Alberta, Edmonton, Alberta, T6J 6J5 Canada
4Department of Biochemistry, University of Alberta, Edmonton, Alberta, T6J 6J5 Canada
5Department of Medicine, University of Alberta, Edmonton, Alberta, T6J 6J5 Canada
Sertoli cells (SC) protect islet allografts from immune destruction in diabetic rodents. In this study, we examined the difference between successful and rejected islet/SC cografts in order to further improve this procedure for optimal extension of islet allograft survival. We cotransplanted 500 BALB/c islets with 1-8 million BALB/c SC under the kidney capsule of diabetic BALB/c, C3H-HeJ, and C57BL/6 mice. Cotransplantation of islets with up to 8 million SC was not detrimental to long-term islet graft function in syngeneic mice. However, large numbers of SC were detrimental to islet graft survival in allogeneic mice with the optimal dose for cotransplantation of 4 or 1 million SC in C3H-HeJ or C57BL/6 mice, respectively. Examination of successful grafts, from euglycemic recipients, revealed the presence of SC arranged in tubule structures with islets surrounding these tubules. Cellular infiltrate in successful grafts revealed CD4 T cells and macrophages along the periphery and within the grafts, and very few CD8 T cells. Conversely, examination of unsuccessful grafts, harvested from hyperglycemic recipients at the time of rejection, revealed the presence of SC arranged randomly with islets adjacent to the Sertoli cells, when present, and massive CD4 and CD8 T cell as well as macrophage cell infiltration. Prolongation of islet allograft survival appeared to be a function of SC transplant mass and recipient genetic background. A consequence of long-term graft acceptance is the formation of SC tubule structures, which may be an additional requirement for optimal protection of islet allografts.
Key words: Sertoli cell; Islet; Transplantation; Diabetes
Address correspondence to Dr. Ray V. Rajotte, Director, Surgical-Medical Research Institute, 1074 Dentistry/Pharmacy Centre, University of Alberta, Edmonton, Alberta, Canada T6G 2N8. Tel: (780) 492-3386; Fax: (780) 492-1627; E-mail: firstname.lastname@example.org
*Jannette M. Dufour and Sarah J. Lord contributed equally to this work.
Automated, High-Throughput Assays for Evaluation of Human Pancreatic Islet Function
Over Cabrera,1,2 M. Caroline Jacques-Silva,1 Dora M. Berman,1 Alberto Fachado,1 Felipe Echeverri,3 Ramon Poo,3 Aisha Khan,1 Norma S. Kenyon,1 Camillo Ricordi,1 Per-Olof Berggren,1,2 and Alejandro Caicedo1
1Diabetes Research Institute, Miller School of Medicine,
University of Miami, Miami, FL, USA
2The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, Stockholm, Sweden
3Biorep®Technologies, Inc., Miami, FL, USA
An important challenge in pancreatic islet transplantation in association with type 1 diabetes is to define automatic high-throughput assays for evaluation of human islet function. The physiological techniques presently used are amenable to small-scale experimental samples and produce descriptive results. The postgenomic era provides an opportunity to analyze biological processes on a larger scale, but the transition to high-throughput technologies is still a challenge. As a first step to implement high-throughput assays for the study of human islet function, we have developed two methodologies: multiple automated perifusion to determine islet hormone secretion and high-throughput kinetic imaging to examine islet cellular responses. Both technologies use fully automated devices that allow performing simultaneous experiments on multiple islet preparations. Our results illustrate that these technologies can be applied to study the functional status and explore the pharmacological profiles of islet cells. These methodologies will enable functional characterization of human islet preparations before transplantation and thereby provide the basis for the establishment of predictive tests for b-cell potency.
Key words: High-throughput assay; Pancreatic islets; Human islet function; Type 1 diabetes
Address correspondence to Alejandro Caicedo, Diabetes Research Institute, Miller School of Medicine, University of Miami, 1450 NW 10th Avenue, Miami, FL 33136, USA. Tel: 305 243 3326; Fax: 305 243 4404; E-mail: email@example.com or Per-Olof Berggren, The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, Karolinska University Hospital L1, SE-171 76 Stockholm, Sweden. Tel: +46 8 517 757 31; Fax: +46 8 517 717 81; E-mail: firstname.lastname@example.org
Multifunctional Pancreatic Islet Encapsulation Barriers Achieved Via Multilayer PEG Hydrogels
Laney M. Weber,1 Charles Y. Cheung,1,2 and Kristi S. Anseth1,2
1Department of Chemical and Biological Engineering, University
of Colorado, Boulder, CO, 80309-0424, USA
2Howard Hughes Medical Institute, University of Colorado, Boulder, CO, 80309-0424, USA
The diverse requirements for a successful islet encapsulation barrier suggest the benefit of a barrier system that presents differing functionalities to encapsulated cells and host cells. Initially, multifunctional hydrogels were synthesized via the sequential photopolymerization of PEG hydrogel layers, each with different isolated functionalities. The ability to achieve localized biological functionalities was confirmed by immunostaining of different entrapped antibodies within each hydrogel layer. Survival of murine islets macroencapsulated within the interior gel of two-layer hydrogel constructs was then assessed. Maintenance of encapsulated islet survival and function was observed within multilayer hydrogels over 28 days in culture. Additionally, the functionalization of the islet-containing interior PEG gel layer with cell-matrix moieties, with either 100 mg/ml laminin or 5 mM of the adhesive peptide IKVAV found in laminin, resulted in increased insulin secretion from encapsulated islets similar to that in gels without an exterior hydrogel layer. Finally, through cell seeding experiments, the ability of an unmodified, exterior PEG layer to prevent interactions, and thus attachment, between nonencapsulated fibroblasts and entrapped ECM components within the interior PEG layer was demonstrated. Together the presented results support the potential of multilayer hydrogels for use as multifunctional islet encapsulation barriers that provide a localized biologically active islet microenvironment, while presenting an inert, immunoprotective exterior surface to the host environment, to minimize graft-host interactions.
Key words: Islet encapsulation; Multilayer hydrogel; Immunoprotection; Cell-matrix interactions
Address correspondence to Kristi S. Anseth, Department of Chemical and Biological Engineering, University of Colorado, Boulder, CO, 80309-0424, USA. Tel: 1-303-492-3147; Fax: 1-303-735-0095; E-mail: Kristi.Anseth@colorado.edu
Concentration of Bone Marrow Total Nucleated Cells by a Point-of-Care Device Provides a High Yield and Preserves Their Functional Activity
Patrick C. Hermann,1 Stephan L. Huber,1 Tanja Herrler,1 Christoph von Hesler,1 Joachim Andrassy,1 Sherwin V. Kevy,2 May S. Jacobson,2 and Christopher Heeschen1
1Department of Surgery, Ludwig-Maximilians-University, 81377
2CBR Institute for Biomedical Research, Boston, MA 02115, USA
Stem and progenitor cell therapy is a novel strategy to enhance cardiovascular regeneration. Cell isolation procedures are crucial for the functional activity of the administered cellular product. Therefore, new isolation techniques have to be evaluated in comparison to the Ficoll isolation procedure as the current gold standard. Here we prospectively evaluated a novel point-of-care device (Harvest BMAC System) for the concentration of bone marrow total nucleated cells (TNC) in comparison to the Ficoll isolation procedure for bone marrow mononucleated cells (MNC). The yield in total numbers of TNC was 2.4-fold higher for Harvest compared to Ficoll. Despite significant differences in their cellular compositions, the colony-forming capacity was similar for both products. Intriguingly, the migratory capacity was significantly higher for the Harvest TNC (164 ± 66%; p = 0.007). In a mouse model of hind limb ischemia, the increase in blood flow recovery was similar between Harvest BM-TNC and Ficoll BM-MNC (0.53 ± 0.20 vs. 0.46 ± 0.15; p = 0.88). However, adjustment of the injected cell number based on the higher yield of Harvest TNC resulted in a significant better recovery (0.64 ± 0.16 vs. 0.46 ± 0.15; p = 0.003). Cells concentrated by the Harvest point-of-care device show similar or greater functional activity compared to Ficoll isolation. However, the greater yield of cells and the wider range of cell types for the Harvest device may translate into an even greater therapeutic effect.
Key words: Bone marrow; Point of care; Vasculogenesis; Ischemia; Cell therapy
Address correspondence to Dr. Christopher Heeschen, Department of Surgery, Ludwig-Maximilians-University, Marchioninistr. 15, 81377 Munich, Germany. Tel: +49-89-7095-3438; Fax: +49-89-7095-6433; E-mail: email@example.com