|ognizant Communication Corporation|
The Regenerative Medicine Journal
VOLUME 15, NUMBER 3, 2006
Cell Transplantation, Vol. 15, pp. 213-223, 2006
0963-6897/06 $90.00 + 00
Copyright © 2006 Cognizant Comm. Corp.
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Timing of Cord Blood Treatment After Experimental Stroke Determines Therapeutic Efficacy
Jennifer D. Newcomb,1,2 Craig T. Ajmo, Jr.,3 Cyndy D. Sanberg,4 Paul R. Sanberg,1,2,3,4 Keith R. Pennypacker,3 and Alison E. Willing1,2,3
1Center of Excellence for Aging and Brain Repair, University
of South Florida College of Medicine, Tampa, FL 33612, USA
2Department of Neurosurgery, University of South Florida College of Medicine, Tampa, FL 33612, USA
3Department of Pharmacology and Molecular Therapeutics, University of South Florida College of Medicine, Tampa, FL 33612, USA
4Saneron CCEL Therapeutics, Inc., Tampa, FL 33612, USA
Embolic stroke is thought to cause irreparable damage in the brain immediately adjacent to the region of reduced blood perfusion. Therefore, much of the current research focuses on treatments such as anti-inflammatory, neuroprotective, and cell replacement strategies to minimize behavioral and physiological consequences. In the present study, intravenous delivery of human umbilical cord blood cells (HUCBC) 48 h after a middle cerebral artery occlusion (MCAo) in a rat resulted in both behavioral and physiological recovery. Nissl and TUNEL staining demonstrated that many of the neurons in the core were rescued, indicating that while both necrotic and apoptotic cell death occur in ischemia, it is clear that apoptosis plays a larger role than first anticipated. Further, immunohistochemical and histochemical analysis showed a diminished and/or lack of granulocyte and monocyte infiltration and astrocytic and microglial activation in the parenchyma in animals treated with HUCBC 48h poststroke. Successful treatment at this time point should offer encouragement to clinicians that a therapy with a broader window of efficacy may soon be available to treat stroke.
Key words: Human umbilical cord blood; Middle cerebral artery occlusion (MCAo); Inflammation; Infarct core; Therapeutic window
Address correspondence to Alison E. Willing, Department of Neurosurgery, University of South Florida, 12901 Bruce B. Downs Blvd., MDC78, Tampa, FL 33612, USA. Tel: 813-974-7812; Fax: 813-974-3078; E-mail: firstname.lastname@example.org
Genetically Engineered Human Mesenchymal Stem Cells Produce Met-Enkephalin at Augmented Higher Levels In Vitro
Ikuko Sugaya,1 Tingyu Qu,2 Kiminobu Sugaya,1 and George D. Pappas2
1Biomolecular Science Center, Burnett College of Biomedical
Sciences, University of Central Florida, Orlando, FL 32816-2364, USA
2The Psychiatric Institute, Department of Psychiatry, and Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL 60612, USA
We have reported that transplantation of adrenal medullary chromaffin cells that release endogenous opioid peptides into pain modulatory regions in the CNS produce significant antinociceptive effects in patients with terminal cancer pain. However, the usefulness of this procedure is minimal because the availability of human adrenal tissue is very limited. Alternative xenogeneic materials, such as porcine and bovine adrenal chromaffin cells present problems of immune rejection and possible pathogenic contamination. In an attempt to develop opioid peptide-producing cells of autologous origin, we have transfected human mesenchymal stem cells (hMeSCs) with a mammalian expression vector containing a fusion gene of green fluorescent protein (GFP) and human preproenkephalin (hPPE), a precursor protein for enkephalin opioid peptides. Enkephalins are major neurotransmitters that play an important role in analgesia by activating peripheral opioid receptors. Following the establishment of stable transfection of hMeSCs, the expressions of hPPE and GFP were confirmed and the production of methionine enkephalin (Met-enkephalin) was significantly increased compared to control naive hMeSCs (p < 0.05). Our in vitro data demonstrated that genetically engineered hMeSCs with transfected hPPE gene can constitutively produce opioid peptide Met-enkephalin at an augmented high level. hMeSCs are relatively easy to isolate from a patient's bone marrow aspirates and expand in culture by repeated passages. Autologous hMeSCs would not require immunosuppression when transplanted back into the same patient. Through targeted gene manipulation such as hPPE gene transfection, this may offer a virtually unlimited safe cell supply for the treatment of opioid-sensitive pain in humans.
Key words: Preproenkephalin; Gene transfection; Human mesenchymal stem cells; Autologous source; Enkephalins; Antinociception
Address correspondence to Dr. George D. Pappas, The Psychiatric Institute, Department of Psychiatry, University of Illinois at Chicago, 1601 West Taylor Street, Chicago, IL 60612, USA. Tel: 1-312-413-4562; Fax: 1-312-413-4569; E-mail: email@example.com
Behavioral and Histological Characterization of Intrahippocampal Grafts of Human Bone Marrow-Derived Multipotent Progenitor Cells in Neonatal Rats With Hypoxic-Ischemic Injury
Takao Yasuhara,1 Noriyuki Matsukawa,1 Guolong Yu,1 Lin Xu,1 Robert W. Mays,2 Jim Kovach,2 Robert J. Deans,2 David C. Hess,1,3 James E. Carroll,1,3 and Cesar V. Borlongan1,3
1Department of Neurology, Medical College of Georgia, Augusta,
GA 30912, USA
2Department of Regenerative Medicine, Athersys, Inc., Cleveland, OH 44115, USA
3Research & Affiliations Service Line, Augusta VAMC, GA 30912, USA
Children born with hypoxic-ischemic (HI) brain injury account for a significant number of live births wherein no clinical treatment is available. Limited clinical trials of stem cell therapy have been initiated in a number of neurological disorders, but the preclinical evidence of a cell-based therapy for neonatal HI injury remains in its infancy. One major postulated mechanism underlying therapeutic benefits of stem cell therapy involves stimulation of endogenous neurogenesis via transplantation of exogenous stem cells. To this end, transplantation has targeted neurogenic sites, such as the hippocampus, for brain protection and repair. The hippocampus has been shown to secrete growth factors, especially during the postnatal period, suggesting that this brain region presents as highly conducive microenvironment for cell survival. Based on its neurogenic and neurotrophic factor-secreting features, the hippocampus stands as an appealing target for stem cell therapy. Here, we investigated the efficacy of intrahippocampal transplantation of multipotent progenitor cells (MPCs), which are pluripotent progenitor cells with the ability to differentiate into a neuronal lineage. Seven-day-old Sprague-Dawley rats were initially subjected to unilateral HI injury, which involved permanent ligation of the right common carotid artery and subsequent exposure to hypoxic environment. At day 7 after HI injury, animals received stereotaxic hippocampal injections of vehicle or cryopreserved MPCs (thawed just prior to transplantation) derived either from Sprague-Dawley rats (syngeneic) or Fisher rats (allogeneic). All animals were treated with daily immunosuppression throughout the survival period. Behavioral tests were conducted on posttransplantation days 7 and 14 using the elevated body swing test and the rotarod to reveal general and coordinated motor functions. MPC transplanted animals exhibited reduced motor asymmetry and longer time spent on the rotarod than those that received the vehicle infusion. Both syngeneic and allogeneic MPC transplanted injured animals did not significantly differ in their behavioral improvements at both test periods. Immunohistochemical evaluations of graft survival after behavioral testing at day 14 posttransplantation revealed that syngeneic and allogeneic transplanted MPCs survived in the hippocampal region. These results demonstrate for the first time that transplantation of MPCs ameliorated motor deficits associated with HI injury. In view of comparable behavioral recovery produced by syngeneic and allogeneic MPC grafts, allogeneic transplantation poses as a feasible and efficacious cell replacement strategy with direct clinical application. An equally major finding is the observation lending support to the hippocampus as an excellent target brain region for stem cell therapy in treating HI injury.
Key words: Stem and progenitor cells; Syngeneic and allogeneic grafts; Motor behavior; Neurogenesis; Neurotrophic factor
Address correspondence to Cesar V. Borlongan, Ph.D., 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
Progressive Dopamine Neuron Loss in Parkinson's Disease: The Multiple Hit Hypothesis
Paul M. Carvey,1,2 Ashok Punati,1 and Mary B. Newman1,2
1Department of Pharmacology, Rush University Medical Center,
Chicago, IL, USA
2Department of Neuroscience Program, Rush University Medical Center, Chicago, IL, USA
Animal models have been an essential tool for researchers and clinicians in their efforts to study and treat Parkinson's disease (PD). Thus, the various ways 6-hydroxydopamine is employed, the use of MPTP in rodents and nonhuman primates, the prenatal exposure to bacterial endotoxin, the postnatal exposure to environmental toxins such as paraquat and rotenone, the assessment of dopamine (DA) neurons in genetic knockout mouse, and even the behavioral analysis of fruit flies and worms have added significantly to our knowledge base of PD--or have they? Are these animal models manifesting a true model of PD? Have the 7786 published studies (to date) on PD with animal models led to a clearer understanding of its etiology, treatment, or progression? In this review we critically assess this question. We begin with a succinct history of the major contributions, which have led to the current animal models of PD. We then evaluate the primary issue of the progressive loss of DA neurons, which, except for a few studies, has not been addressed in animal models of PD, even though this is the major pathological characteristic of the disease. Lastly, we discuss the possibility that more than one risk factor for PD may be necessary to develop an animal model that shows synergy--the progressive loss of DA neurons. Thus, the multiple hit hypothesis of PD--that is, the effect of more than one risk factor--may be the start of new era in animal models of PD that is one step closer to mimicking the pathology of PD in humans.
Key words: Parkinson's disease; Dopamine neurons; Progression; Multiple hit hypothesis
Address correspondence to Paul M. Carvey, Ph.D., Chairman, Department of Pharmacology, Rush University Medical Center, Cohn Research Building, Suite 406, 1735 W. Harrison Street, Chicago, IL 60612, USA. Tel: 312-563-2563; Fax: 312-563-3552; E-mail: email@example.com
Neural Repair Strategies for Parkinson's Disease: Insights From Primate Models
Katherine Soderstrom,1 Jennifer O'Malley,2 Kathy Steece-Collier,2 and Jeffrey H. Kordower1
1Department of Neurological Science, Research Center for
Brain Repair, Rush University Medical Center, Chicago, IL 60612, USA
2Department of Neurology, University of Cincinnati, Cincinnati, OH 45267, USA
Nonhuman primate models of Parkinson's disease (PD) have been invaluable to our understanding of the human disease and in the advancement of novel therapies for its treatment. In this review, we attempt to give a brief overview of the animal models of PD currently used, with a more comprehensive focus on the advantages and disadvantages presented by their use in the nonhuman primate. In particular, discussion addresses the 6-hydroxydopamine (6-OHDA), 1-methyl-1,2,3,6-tetrahydopyridine (MPTP), rotenone, paraquat, and maneb parkinsonian models. Additionally, the role of primate PD models in the development of novel therapies, such as trophic factor delivery, grafting, and deep brain stimulation, are described. Finally, the contribution of primate PD models to our understanding of the etiology and pathology of human PD is discussed.
Key words: Parkinson's disease; Nonhuman primates; Animal models; Therapeutics
Address correspondence to Jeffrey H. Kordower, Ph.D., The Jean Schweppe-Armour Professor of Neurological Science, Director, Research Center for Brain Repair, Section Head, Neuroscience, 1735 West Harrison Street, Chicago, IL 60612, USA. Tel: (312) 563-3585; Fax: (312) 563-3571; E-mail: firstname.lastname@example.org
CNS Gene Therapy and a Nexus of Complexity: Systems and Biology at a Crossroads
Carolyn M. Tyler and Howard J. Federoff
Center for Aging and Developmental Biology, Aab Institute of Biomedical Sciences, Department of Neurology, University of Rochester School of Medicine and Dentistry, Rochester NY 14642, USA
Gene therapy is a potentially promising new treatment for neurodegenerative disorders such as Alzheimer's disease (AD), which has been difficult to treat with conventional therapeutics. Viral vector-mediated somatic gene therapy is a rapidly developing methodology for providing never before achieved capability to deliver specific genes to the CNS in a highly localized and controlled manner. With the advent and refinements of this technology one focus is directed to which genes are the most appropriate to select for specific disease indications. Nerve growth factor (NGF), a potent survival factor for critical cell populations that degenerate in AD, has been chosen already for clinical gene therapy trials in human AD patients. Much knowledge about the pathophysiological underpinnings of AD is still lacking to make clear which patients may benefit from a gene therapy approach. Moreover, a detailed understanding of sustained NGF action in the normal and diseased CNS needs to be resolved before conclusions can be drawn regarding the utility of NGF gene therapy. Systematic efforts to acquire this new knowledge should compel clinically and biologically sophisticated efforts to advance gene therapy for neurodegenerative diseases.
Key words: Gene therapy; CNS; Neurodegenerative diseases; Nerve growth factor
Address correspondence to Howard J. Federoff, M.D., Ph.D., Center
for Aging and Development Biology, Arthur Kornberg Medical Research Bldg.,
University of Rochester School of Medicine and Dentistry, 601 Elmwood Ave.,
Box 645, Rochester, NY 14642, USA. Tel: 585-273-2190; Fax: 858-506-1957;