|ognizant Communication Corporation|
The Regenerative Medicine Journal
VOLUME 19, NUMBER 2, 2010
Cell Transplantation, Vol. 19, pp. 133-146, 2010
0963-6897/10 $90.00 + 00
Copyright © 2010 Cognizant Comm. Corp.
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Shotgun Proteomics and Network Analysis Between Plasma Membrane and Extracellular Matrix Proteins From Rat Olfactory Ensheathing Cells
Yisong Liu,1* Xiaohua Teng,2* Xiaoxu Yang,1 Qing Song,1 Rong Lu,1 Jixian Xiong,1 Bo Liu,2 Nianju Zeng,2 Yu Zeng,2 Jia Long,1 Rui Cao,1 Yong Lin,1 Quanze He,1 Ping Chen,1 Ming Lu,2 and Songping Liang1
1Key laboratory of Protein Chemistry and Developmental Biology
of Ministry of Education, College of Life Sciences, Hunan Normal University,
Changsha, P.R. China
2Department of Neurosurgery, Second Affiliated Hospital of Hunan Normal University (163 Hospital of PLA), Changsha, P.R. China
Olfactory ensheathing cells (OECs) are a special type of glial cells that have characteristics of both astrocytes and Schwann cells. Evidence suggests that the regenerative capacity of OECs is induced by soluble, secreted factors that influence their microenvironment. These factors may regulate OECs self-renewal and/or induce their capacity to augment spinal cord regeneration. Profiling of plasma membrane and extracellular matrix through a high-throughput expression proteomics approach was undertaken to identify plasma membrane and extracellular matrix proteins of OECs under serum-free conditions. 1D-shotgun proteomics followed with gene ontology (GO) analysis was used to screen proteins from primary culture rat OECs. Four hundred and seventy nonredundant plasma membrane proteins and 168 extracellular matrix proteins were identified, the majority of which were never before reported to be produced by OECs. Furthermore, plasma membrane and extracellular proteins were classified based on their protein-protein interaction predicted by STRING quantitatively integrates interaction data. The proteomic profiling of the OECs plasma membrane proteins and their connection with the secretome in serum-free culture conditions provides new insights into the nature of their in vivo microenvironmental niche. Proteomic analysis for the discovery of clinical biomarkers of OECs mechanism warrants further study.
Key words: Olfactory ensheathing cells; Neural repair; 1D-shotgun proteomics; Plasma membrane; Extracellular matrix
Address correspondence to Ping Chen, Key laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, 410081, P.R. China. E-mail: email@example.com or Ming Lu, Department of Neurosurgery, Second Affiliated Hospital of Hunan Normal University (163 Hospital of PLA), Changsha, P.R. China. E-mail: firstname.lastname@example.org or Songping Liang, Key laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, 410081, P.R. China. E-mail: email@example.com
*Both authors contributed equally to this work.
Guidance of Olfactory Ensheathing Cell Growth and Migration on Electrospun Silk Fibroin Scaffolds
Yixin Shen,1* Yuqiang Qian,1* Huanxiang Zhang,2 Baoqi Zuo,3 Zhenfeng Lu,1 Zhihai Fan,1 Peng Zhang,1 Feng Zhang,3 and Chunlei Zhou2
1Department of Orthopedics, the Second Affiliated Hospital
of Soochow University, Suzhou Jiangsu, P.R. China
2Jiangsu Province Key Laboratory of Stem Cell Research, Medical College of Soochow University, Suzhou Jiangsu, P.R. China
3Material Engineering Institute, Soochow University, Suzhou Jiangsu, P.R. China
Transplantation of olfactory ensheathing cells (OECs) is a potential treatment for spinal cord injury (SCI). However, this process lacks extracellular matrix guiding cell growth, tissue morphogenesis, and remodeling. In order to solve this problem, we fabricated silk fibroin scaffolds (SFS) with different fiber diameters by electrospinning. The behaviors of OECs on 300 and 1800 nm SFS were studied by analyzing cell morphological feature, distribution, and proliferation. The results showed the 300 nm SFS with good potential to guide OECs growth. Subsequently, the properties of 300 nm SFS were further investigated along with PLL. With 300 nm SFS, the preservation of cell phenotype was confirmed by the presence of cell-specific markers, including nerve growth factor receptor p75 and glial fibrillary acidic protein. And the migration behaviors of OECs were also observed by Leica AF6000. In addition, migration tracks, turning behavior, migration distances, migration speeds, and forward migration indices were calculated. Furthermore, the expression of neurotrophic factors was assayed at transcription and protein levels using RT-PCR and ELISA. All these results indicated the diameter of the fiber played an important role in guiding cell adhesion, growth, and migration in vitro and the 300 nm SFS could be suitable to construct tissue-engineered scaffolds for SCI repair.
Key words: Olfactory ensheathing cells; Silk fibroin scaffolds; Electrospinning; Cell migration; Growth factors; Tissue engineering
Address correspondence to Yixin Shen, Department of Orthopedics, the Second Affiliated Hospital of Soochow University, 1055 Sanxiang Road, Suzhou Jiangsu 215006, P.R. China. Tel: (+86) 512-6778-4815; E-mail: firstname.lastname@example.org or email@example.com
*These authors contributed equally to this work.
Death of Axotomized Retinal Ganglion Cells Delayed After Intraoptic Nerve Transplantation of Olfactory Ensheathing Cells in Adult Rats
Ming-Mei Wu,1* De-Gang Fan,2* Iman Tadmori,3 Hao Yang,1 Maya Furman,3 Xi-Ying Jiao,1 Wise Young,3 Dongming Sun,3 and Si-Wei You1
1Institute of Neurosciences, the Fourth Military Medical
University, Xi'an, China
2Institute of Orthopedic Oncology, Tangdu Hospital, the Fourth Military Medical University, Xi'an, China
3Department of Cell Biology & Neuroscience, W. M. Keck Center for Collaborative Neuroscience, Rutgers, the State University of New Jersey, Piscataway, NJ, USA
Intraorbital transection of the optic nerve (ON) always induces ultimate apoptosis of retinal ganglion cells (RGCs) and consequently irreversible defects of vision function. It was demonstrated that transplanted olfactory ensheathing cells (OECs) in partially injured spinal cord have a distant in vivo neuroprotective effect on descending cortical and brain stem neurons. However, this study gave no answers to the question whether OECs can protect the central sensitive neurons with a closer axonal injury because different neurons respond variously to similar axonal injury and the distance between the neuronal soma and axonal injury site has a definite effect on the severity of neuronal response and apoptosis. In the present study, we investigated the effect of transplanted OECs on RGCs after intraorbital ON transection in adult rats. Green fluorescent protein (GFP)-OECs were injected into the ocular stumps of transected ON and a significantly higher number of surviving RGCs was found together with a consistent marked increase in the mRNA and protein levels of BDNF in the ON stump and retina in the OEC-treated group at 7 days, but not 2 and 14 days, time point when compared to the control group. Our findings suggest that OEC transplantation induces the expression of BDNF in the ocular ON stump and retina and delays the death of axotomized RGCs at a certain survival period.
Key words: Olfactory ensheathing cell transplantation; Optic nerve transection; Retinal ganglion cells; Neuroprotection
Address correspondence to Si-Wei You, Institute of Neurosciences, The Fourth Military Medical University, Xi'an, 710032 China. E-mail: firstname.lastname@example.org or Dongming Sun, Department of Cell Biology & Neuroscience, W. M. Keck Center for Collaborative Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ 08854. E-mail: email@example.com
*Ming-Meu Wu and De-Gang Fan contributed equally to this work.
Effect of Neurotrophin-3 Genetically Modified Olfactory Ensheathing Cells Transplantation on Spinal Cord Injury
Yu-Hai Ma,1* Yong Zhang,2*# Li Cao,2 Jia-Can Su,3 Zhi-Wei Wang,3 A-Bing Xu,1 and Shao-Cheng Zhang3
1Department of Orthopaedic, Zhejiang Provincial Corps Hospital,
Chinese People's Armed Polices Forces, Jiaxing, China
2Department of Neurobiology, Second Military Medical University, Shanghai, China
3Department of Orthopaedic, Changhai Hospital, Second Military Medical University, Shanghai, China
Transplantation of olfactory ensheathing cells (OECs) has emerged as a very promising therapy for spinal cord injury (SCI). Also, local delivery of NT-3 can counteract pathological events and induce a regenerative response after SCI. Supplement of exogenetic NT-3 might be a new approach to SCI repair. In this study, we examined the therapeutic effect of rat NT-3 gene-modified OECs transplantation on SCI. Rat NT-3 gene was transfected into OECs using a retroviral system. The engineered NT-3-OECs were tested for their ability to express and secrete biologically active NT-3 in vitro. Then NT-3-OECs were implanted into contused T9 spinal cord of the adult rats. Their ability of survival and NT-3 production was examined. The effect of axon regeneration was evaluated at the morphological level and promotion of locomotor functional recovery were assessed. The result showed that genetically modified OECs were capable of surviving and producing NT-3 in vivo to significantly improve the recovery after SCI.
Key words: Spinal cord injury (SCI); Olfactory ensheathing cells (OECs); Neurotrophin-3 (NT-3); Transplantation; Gene therapy
Address correspondence to Shao-Cheng Zhang, Department of Orthopaedic, Changhai Hospital, Second Military Medical University, Shanghai 200433, China. E-mail: firstname.lastname@example.org
*These authors contributed equally to this paper.
#Current address: Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA.
Olfactory Ensheathing Glia Transplantation Combined With LASERPONCTURE® in Human Spinal Cord Injury: Results Measured by Electromyography Monitoring
Laboratoire de Recherches sur le LASERPONCTURE®, La Chapelle Montlinard, France
Preliminary results were measured by electromyography monitoring (electromyoscan) on three subjects suffering from spinal cord injury and who underwent a double therapy. The aim of this study was to evaluate regained voluntary activity below the injury in subjects who received a double therapy: 1) an olfactory ensheathing glia (OEG) transplantation using procedures developed by Dr. Hongyun Huang at the Xishan Hospital and Rehabilitation Centre, Beijing, China, and 2) LASERPONCTURE® developed by Albert Bohbt, Laboratoire de Recherches sur le LASERPONCTURE®, La Chapelle Montlinard, France. Materials uses were the LASERPONCTURE® device developed by Albert Bohbot; the PROCOMP5TM equipment with softwares BIOGRAPH INFINITI 5® and REHAB SUITETM; the sensors MYOSCAN-PROTM EMG (SA9401M-50) to record muscle activity, and FLEX/PROTM-SA9309M to record skin conductance were fixed on the skin. An infrared laser, whose frequencies and power settings cannot be disclosed due to its proprietary nature, was applied after an OEG injection performed according to Dr. Hongyun Huang's procedures. Three cases, two males and one female, were selected for this study. Presentation and comments of the graphs recordings of voluntary muscle activity below the injury are provided. This preliminary study suggests that the double therapy restores some voluntary muscle activity as measured by electromyography monitoring.
Key words: LASERPONCTURE®; Olfactory ensheathing glia (OEG); Paraplegia; Quadriplegia; Spinal cord injury; Electromyography monitoring
Address correspondence to Albert Bohbot, Laboratoire de Recherches sur le LASERPONCTURE®, Château Gaillard, 33 route du Canal, 18140 La Chapelle Montlinard, France. Tel/Fax: +33 248794361; E-mail: email@example.com
Intracranial Transplant of Olfactory Ensheathing Cells in Children and Adolescents With Cerebral Palsy: A Randomized Controlled Clinical Trial
Lin Chen,1,2 Hongyun Huang,1,2 Haitao Xi,1,2 Zihang Xie,1 Ruiwen Liu,1 Zhao Jiang,1 Feng Zhang,1 Yancheng Liu,1 Di Chen,1 Qingmiao Wang,1 Hongmei Wang,1,2 Yushui Ren,2 and Changman Zhou2,3
1Center for Neurorestoratology, Beijing Rehabilitation Center,
Beijing, P.R. China
2Beijing Hongtianji Neuroscience Academy, Beijing, P.R. China
3Department of Anatomy and Embryology, Peking University Health Science Center, Beijing, P.R. China
Successful repair of damage in cerebral palsy (CP) needs effective clinical interventions other than simply symptomatic treatments. To elucidate the feasibility of using olfactory ensheathing cells (OECs) to treat CP in children and adolescents, we conducted a randomized controlled clinical trial (RCT) on 33 patients. The patients were randomly assigned into two groups (treatment group, n = 18; control group, n = 15), and OECs derived from aborted fetal tissue were injected into the bilateral corona radiata in the frontal lobes (a key point for neural network restoration, KPNNR). The Gross Motor Function Measure (GMFM-66) and the Caregiver Questionnaire Scale were used to evaluate the patients' neurological function and overall health status. Among the 14 patients who completed the 6-month study, six received the cell transplantation and the other eight served as controls. In OEC treatment group, GMFM-66 scores were 26.67 ± 25.33 compared with 19.00 ± 20.00 for the control group. Concurrently, the Caregiver Questionnaire Scale score decreased to 77.83 ± 15.99 in the treatment group in comparison to 138.66 ± 64.06 of the control group. This trial, albeit small in sample size, indicates OEC KPNNR transplantation is effective for functional improvement in children and adolescents with CP, yet without obvious side effects. This small-scale study suggests that the procedure may be a plausible alternative method to treat this not yet curable disorder, and we urge further evaluation with a large-scale RCT.
Key words: Cerebral palsy; Olfactory ensheathing cells; Transplantation; Clinical trial; Key point for neural network restoration (KPNNR)
Address correspondence to Hongyun Huang, M.D., Ph.D., Center for Neurorestoratology, Beijing Rehabilitation Center, Beijing, 100144, P.R. China. Tel: 86-10-5882-3400; Fax: 86-10-5162-5950; E-mail: firstname.lastname@example.org
Purification of Mouse Bone Marrow-Derived Stem Cells Promotes Ex Vivo Neuronal Differentiation
Mohammad Jamous,1* Adeeb Al-Zoubi,2* Mohamad Nidal Khabaz,3 Rana Khaledi,4 Mohammad Al Khateeb,6 and Zaid Al-Zoubi6
1Department of Neurosciences, Faculty of Medicine, Jordan
University of Science and Technology, Irbid, Jordan
2Department of Biotechnology and Genetic Engineering, College of Science, Philadelphia University, Amman, Jordan
3Department of Pathology, Faculty of Medicine, Jordan University of Science and Technology, Irbid, Jordan
4Department of Biology, Faculty of Sciences and Arts, Jordan University of Science and Technology, Irbid, Jordan
5Department of Pathology, Faculty of Medicine, University of Jordan, Amman, Jordan
6Jordan Orthopedic and Spine Center, Amman, Jordan
The main objective of this study is to test the potential of specific populations of mouse bone marrowderived stem cells (BMSCs) to differentiate into the neuronal cell lineage. Bone marrow of 33 mice was aspirated under general anesthesia. The collected marrows were analyzed for cell counts, compositions, and percentages of different stem cell types. We used the Midi MACS magnetic separator to purify specific populations of stem cells from the aspirated bone marrow. Cells were analyzed using flow cytometry. We assessed the presence of stem cell antigen-1 (Sca-1+) and prominin-1+ cells in the cellular fraction that was depleted of lineage-committed cells (lineage-). Both purified and nonpurified cells were cultured ex vivo using specific growth media with factors that drive the cells to differentiate into the neuroglial cell types. Cells were then analyzed by flow cytometry for expression of specific neuronal markers. Our results showed that there was an increase of Sca-1+ and prominin-1+ cells in the lineage<s>- fraction over the unpurified BM. After lineage depletion, the percentages of Sca-1+ and prominin-1+ cells increased from 4.9% and 2.6%, up to 76.1% and 59%, respectively. Unpurified mouse BM differentiated into fibroblasts, whereas Sca-1+ cells were able to generate astrocytes. Interestingly, purified prominin-1+ cells were able to generate neuronal cells. Purification of adult bone marrow-derived stem cells enhances their potentiality for differentiating into specific neuronal cell lineages.
Key words: Sca-1; Prominin-1; Neuronal differentiation; Adult stem cell; Lineage depletion; Magnetic separator
Address correspondence to Mohammad Jamous, M.D., Ph.D., Department of Neurosciences, Faculty of Medicine, Jordan University of Science and Technology, P.O. Box 3030, Irbid- 22110, Jordan. Tel: 0096279-9773827; E-mail: email@example.com
*These two authors contributed equally to this article.
Transplantation of Undifferentiated Human Mesenchymal Stem Cells Protects Against 6-Hydroxydopamine Neurotoxicity in the Rat
Fabio Blandini,1 Lidia Cova,2 Marie-Therese Armentero,1 Eleonora Zennaro,2 Giovanna Levandis,1 Patrizia Bossolasco,3 Cinzia Calzarossa,2 Manuela Mellone,2 Busca Giuseppe,4 Giorgio Lambertenghi Deliliers,5 Elio Polli,3 Giuseppe Nappi,1,6 and Vincenzo Silani2
1Interdepartmental Research Center for Parkinson's Disease,
IRCCS Neurological Institute "C. Mondino," Pavia, Italy
2Department of Neurology and Laboratory of Neuroscience, "Dino Ferrari" Center, Università degli Studi di Milano-IRCCS Istituto Auxologico Italiano, Milan, Italy
3Fondazione Matarelli, Department of Pharmacology, Chemotherapy and Medical Toxicology, Università degli Studi di Milano, Milan, Italy
4Medical Cardiovascular Institute, Maggiore Hospital Policlinico Mangiagalli e Regina Elena, Milan, Italy
5Ematologia 1, Bone Marrow Transplant Unit, IRCCS Maggiore Hospital, Università degli Studi di Milano, Milan, Italy
6Chair of Neurology, University of Rome "La Sapienza," Rome, Italy
Stem cells have been increasingly recognized as a potential tool to replace or support cells damaged by the neurodegenerative process that underlies Parkinson's disease (PD). In this frame, human adult mesenchymal stem cells (hMSCs) have been proposed as an attractive alternative to heterologous embryonic or neural precursor cells. To address this issue, in this study we implanted undifferentiated hMSCs into the striatum of rats bearing a lesion of the nigrostriatal pathway induced by local injection of 6-hydroxydopamine (6-OHDA), a widely recognized rodent model of PD. Before grafting, cultured hMSCs expressed markers of both undifferentiated and committed neural cells, including nestin, GAP-43, NSE, b-tubulin III, and MAP-2, as well as several cytokine mRNAs. No glial or specific neuronal markers were detected. Following transplantation, some hMSCs acquired a glial-like phenotype, as shown by immunoreactivity for glial fibrillary acid protein (GFAP), but only in animals bearing the nigrostriatal lesion. More importantly, rats that received the striatal graft showed increased survival of both cell bodies and terminals of dopaminergic, nigrostriatal neurons, coupled with a reduction of the behavioral abnormalities (apomorphine-induced turning behavior) associated with the lesion. No differentiation of the MSCs toward a neuronal (dopaminergic) phenotype was observed in vivo. In conclusion, our results suggest that grafted hMSCs exert neuroprotective effects against nigrostriatal degeneration induced by 6-OHDA. The mechanisms underlying this effect remain to be clarified, although it is likely that the acquisition of a glial phenotype by grafted hMSCs may lead to the release of prosurvival cytokines within the lesioned striatum.
Key words: Substantia nigra; Striatum; Graft; 6-Hydroxydopamine; Neuroprotection; Cytokines; Rat
Address correspondence to Fabio Blandini, M.D., IRCCS Neurological Institute "C. Mondino,", Via Mondino, 2 27100 Pavia, Italy. Tel: +39 0382 380416; Fax: +39 0382 380448; E-mail: firstname.lastname@example.org
Time-Dependent Migration of Systemically Delivered Bone Marrow Mesenchymal Stem Cells to the Infarcted Heart
Ana Carolina M. Assis,1 Juliana L. Carvalho,2 Bruno A. Jacoby,1 Raphael L. B. Ferreira,3 Paula Castanheira,2 Simone O. F. Diniz,3 Valbert N. Cardoso,3 Alfredo M. Goes,2 and Anderson J. Ferreira1
1Department of Morphology, Biological Sciences Institute,
Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
2Department of Biochemistry and Immunology, Biological Sciences Institute, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
3Department of Clinical and Toxicological Analysis, Pharmacy Faculty, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
In this study the time course of homing and the body distribution of systemically delivered bone marrow mesenchymal stem cells (BM-MSCs) after myocardial infarction (MI) were evaluated. BM-MSCs were isolated from Wistar rats, expanded in vitro, and their phenotypical characterization was performed by flow cytometer. Rats were randomly divided into three groups: control, sham MI, and MI. BM-MSCs (5 x 106) were labeled with 99mTc-HMPAO and injected through the tail vein 7 days after MI. Gamma camera imaging was performed at 5, 15, 30, and 60 min after cell inoculation. Due to the 99mTc short half-life, cell migration and location were also evaluated in heart sections using DAPI-labeled cells 7 days after transplantation. Phenotypical characterization showed that BM-MSCs were CD90+, CD73+, CD54+, and CD45-. Five minutes after 99mTc-HMPAO-labeled cell injection, they were detected in various tissues. The cells migrated mainly to the lungs (approximately 70%) and, in small amounts, to the heart, kidneys, spleen, and bladder. The number of cells in the heart and lungs decreased after 60 min. MI markedly increased the amount of cells in the heart, but not in the lungs, during the period of observation (4.55 ± 0.32 vs. 6.34 ± 0.67% of uptake in infarcted hearts). No significant differences were observed between control and sham groups. Additionally, 7 days after DAPI-labeled cells injection, they were still detected in the heart but only in infarcted areas. These results suggest that the migration of systemically delivered BM-MSCs to the heart is time dependent and MI specifically increases BM-MSCs homing to injured hearts. However, the systemic delivery is limited by cell entrapment in the lungs.
Key words: Myocardial infarction; Mesenchymal stem cells; Homing; Body distribution
Address correspondence to Anderson J. Ferreira, Ph.D., Department of Morphology, Av. Anto^nio Carlos, 6627-ICB, UFMG, 31 270-901, Belo Horizonte, MG, Brazil. Tel: (55-31)3409-2811; Fax: (55-31)3409-2810; E-mail: email@example.com
Hepatocyte Transplantation and the Differentiation Fate of Host Oval Cells in Acute Severe Hepatic Injury
Chun-Hsien Yu,1,2 Mei-Hwei Chang,1,3,4 Chin-Sung Chien,1,3,4 Ya-Hui Chen,1,3,4 Ming-Fu Chang,5 and Hui-Ling Chen4
1Graduate Institute of Clinical Medicine, National Taiwan
University Hospital and National Taiwan University College of Medicine,
2Department of Pediatrics, Buddhist Tzu-Chi General Hospital, Taipei Branch, and Buddhist Tzu-Chi University College of Medicine, Taipei, Taiwan
3Department of Pediatrics, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan
4Hepatitis Research Center, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan
5Graduate Institute of Biochemistry and Molecular Biology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan
Oval cells and hepatocytes rarely proliferate simultaneously. This study aimed to determine the impacts of hepatocyte transplantation on the response and fate of oval cells that are activated to proliferate in acute severe hepatic injury. Retrorsine + D-galactosamine (R+D-gal) treatment was used to induce acute hepatic injury and to elicit extensive activation of oval cells in male dipeptidyl peptidase IV-deficient F344 rats. These rats were then randomized to receive wild-type hepatocyte transplantation or vehicle intraportally. The kinetics of oval cell response and their differentiation fate were analyzed. Results showed that oval cells were activated early and differentiated into hepatocytes in R+D-gal-treated rats without hepatocyte transplantation. With hepatocyte transplantation, the oval cells were recruited later and continued to proliferate in parallel with the massive proliferation of transplanted hepatocytes. They formed ductules and differentiated into biliary cells. When hepatocytes were transplanted at the day when oval cells were at their peak response, the numerous activated oval cells ceased to differentiate into hepatocytes and remained in ductular form. The ductular oval cells were capable of differentiating into hepatocytes again when the donor hepatocytes were inhibited to proliferate. We conclude that hepatocyte transplantation changes the mechanism of liver reconstitution and affects the differentiation fate of host oval cells in acute severe hepatic injury.
Key words: Cell differentiation; D-Galactosamine; Progenitor cell; Regeneration; Retrorsine
Address correspondence to Hui-Ling Chen, Ph.D., Hepatitis Research Center, National Taiwan University Hospital, No. 7, Chung-Shan S. Road, Taipei 100, Taiwan. Tel: +886-2-23123456, ext. 67505; Fax: +886-2-23825962; E-mail: firstname.lastname@example.org
Making Stem Cells Infarct Avid
Ming Zhao,1 Matthew R. Barron,2* Zhixin Li,1 Stacy Koprowski,2 Cherisse L. Hall,1 and John Lough2
1Department of Biophysics, Medical College of Wisconsin,
Milwaukee, WI, USA
2Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA
A major factor limiting the engraftment of transplanted stem cells after myocardial infarction is the low rate of retention in the infarcted site. Our long-term objective is to improve engraftment by enabling stem cells to recognize and bind infarcted tissue. To this end, we proposed to modify the surface of embryonic stem cells (ESCs) with the C2A domain of synaptotagmin I; this allows the engineered stem cells to bind to dead and dying cardiac cells by recognizing phosphatidylserine (PS). The latter is a molecular marker for apoptotic and necrotic cells. The C2A domain of synaptotagmin I, which binds PS with high affinity and specificity, was attached to the surface of mouse ESCs using the biotin-avidin coupling mechanism. Binding of C2AESCs to dead and dying cardiomyocytes was tested in vitro. After the surface modification, cellular physiology was examined for viability, pluripotency, and differentiation potential. C2A covalently attached to the ESC surface at an average of about 1 million C2A molecules per cell under mild conjugation reaction conditions. C2A-ESCs avidly bound to dying, but not viable, cardiomyocytes in culture. The normal physiology of C2A-modified ESCs was maintained. The binding of C2A-ESCs to moribund cardiomyocytes demonstrates that the retention of transplanted cells may be improved by conferring these cells with the ability to bind infarcted tissue. Once established, this novel approach may be applicable to other types of transplanted therapeutic cells.
Key words: Stem cells; Acute myocardial infarction; C2A domain of synaptotagmin I; Phosphatidylserine; Apoptosis; Necrosis
Address correspondence to Ming Zhao, Ph.D., Department of Biophysics, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI, 53226, USA. Tel: 414-456-4059; Fax: 414-456-6512; E-mail: email@example.com
*Current address: Department of Medicine, University of Wisconsin Madison, Madison, WI, USA.