2/12/2009. Virus enters here. Rakic, JCN, 1972

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1 Stem Cell Update Feb. 12, 2009 Arnold R. Kriegstein, MD, PhD, Department of Neurology, Director, Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research at UCSF Virus enters here Rakic, JCN,

2 VZ is a niche for asymmetric neurogenic divisions is a niche for symmetric neurogenic divisions 2

3 Location of Tbr2+ cells in the developing cortex Asymmetric neurogenesis (neuronal diversity) E17 E20 E15 E12 Symmetric neurogenesis (neuronal multiplication) Kornack, Rakic, Neuron,

4 Do intermediate progenitor cells contribute to the expansion of primate cerebral cortex? wt mouse β-catenin mouse Gyrencephalic adult ferret Chenn and Walsh, 2002 Symmetric radial glial divisions expand founder cell population Symmetric neural stem cell (radial glial) divisions pia pia ventricle ventricle 4

5 Primate Mouse Smart et al, 2003 Mouse E13.5 Human GW14 GFP retrovirus and slice culture labels radial clones in the O Pax6 666 Sox2 Tbr2 PH3 Outer VZ Inner VZ Jan Lui, David Hansen 5

6 Cortical plate Rakic, 1972; 1978 Cortical plate Outer Inner VZ Summary Radial glia generate neurons directly and through intermediate precursor cells Radial glia undergo asymmetric division ( generate neuronal diversity) Intermediate progenitor cells undergo symmetric divisions (expand neuron number) stem cell targets Human outer contains IPCs and displaced radial glia After embryonic neurons are produced radial glia transform into astrocytes 6

7 Sanai et al, Nature 2004 Radial ependymoglial cells persist in the brains of adult reptiles 7

8 Where do stem cells come from? A stem cell primer 1981 Gail Martin vs. Martin Evans and M. H. Kaufman 1998 James Thomson makes hesc lines 2001 George Bush forbids NIH support for making new hescs Single-cell embryo 3 day embryo 5-7 day embryo t Human developmental continuum Embryonic stem (ES) cells 4 week embryo 6 week embryo Embryo 3-5 days Adult organs Stem cell line Factors Placenta Cord blood Bone marrow Skin biopsy The Therapeutic Promise of stem cells Regenerative therapy (replace dead/injured tissue) Deliver Genes/Drugs/Trophic factors Drug Discovery and testing Understand Human Development Study Human Disease Ectoderm Brain Skin Mesoderm Muscle Blood Endoderm Lung Gut Liver Germline Sperm Egg 8

9 Why PD is attractive for stem cell therapy Progress in deriving human DA neurons from ESCs Neural induction Neural patterning Differentiation Dopamine neurons Perrier, Studer, et al., PNAS, 2004 Fetal transplants ( proof of principle?) Dopamine production may be sustained open-label trials showed cell survival and function 1990s two NIH funded double-blind blind sham surgery controlled trials: minimal effectiveness adverse side effects Freed et al., NEJM,

10 Grafted neurons can survive and produce DA Grafted cells can show signs of PD Substantia Nigra (PD) Graft α-synuclein α-synuclein Kordower et al., Nature Neurosci, 2008 Problems with fetal midbrain grafts that stem cells may overcome: Too few neurons (unlimited supply) Variable quality and cell preparation (standardized defined cell type) The Therapeutic Promise of stem cells For the study of human disease Poor migration and integration (better integration?) Graft rejection (patient-specific cells) 10

11 ALS Wichterle et al, Cell, 2002 Wichterle et al, Cell, 2002 Embryonic Stem Cells show astrocytes poison motor neurons in ALS Induced Pluripotent Stem (ips) Cells for the study of ALS Astrocytes expressing ALS-linked mutated SOD1 release factors selectively toxic to motor neurons Makiko Nagai, Diane B Re, Tetsuya Nagata, Alcmène Chalazonitis, Thomas M Jessell, Hynek Wichterle & Serge Przedborski Nature Neuroscience April 2007 Non cell autonomous effect of glia on motor neurons in an embryonic stem cell based ALS model Francesco Paolo Di Giorgio, Monica A Carrasco, Michelle C Siao, Tom Maniatis & Kevin Eggan Nature Neuroscience April 2007 ips 11

12 Status Cell type Company Disease target On-going Human fetal NSCs Stem Cells Inc. Batten s disease Approved hesc-derived OPCs Geron Inc. Spinal Cord Injury Pending hesc-derived pigment epithelia Human fetal NSCs Clinical Trials Autologous BM-derived cells stroke, spinal cord injury, etc. Technology has outpaced our understanding. ACT Inc., The London Project to Cure AMD ReNeuron Group Plc Macular Degeneration Stroke Also close behind: Osiris Therapeutics Inc., Cytori Therapeutics Inc., Novocell, and others. Future Prospects Improved methods to generate specific neuron or glial subtypes hesc-derived neurons for modeling disease: ALS, Huntington s disease, Alzheimer s disease, etc. Cell-based therapies: PD, Stroke, Spinal injury, spinal muscular atrophy, ALS, etc. Challenge: self-renewal may produce tumors Important Future Directions Complete the Stem Cell Building Construction and site development cost of $103M 45,000 asf to house 25 investigators representing cardiovascular, neural, pancreas and liver, hematopoiesis, musculoskeletal, epithelial, and reproduction pipelines. House core facilities in cell sorting, imaging, cell tracking, histology, high-throughput DNA sequencing, bioinformatics, and clinical trail design, as well as labs to derive new hesc lines. An existing GMP facility complements the cores. Recruit Faculty Currently comprised of 123 principal investigators, 74 core clinician and scientists 17 experts recruited over four years (including Shinya Yamanaka) in: skin-derived stem cells, liver regeneration, islet cell production, leukemia-producing stem cells, cell therapy of multiple sclerosis and cerebral palsy, cell reprogramming, brain tumor stem cells, fetal surgery to treat congenital disorders, bioengineering, cartilage and bone regeneration, germ cell production, and spinal cord injury. Build translational teams linking scientists and clinicians 12

13 Wichterle et al, Cell, 2002 Park et al., Bio Reprod, 2003 Long QT carrier ips-derived cardiomyocytes provide a powerful new platform to study heart rhythm and and for safety screening of new drugs Sanai et al, NEJM,

14 Human stem cells grown on human placental cell feeders (From the Fisher laboratory at UCSF) How embryonic stem cells are derived Day 1 Day 5 IVF Clinic Colony size: 156,206 µm 2 Colony size: 3,674,083 µm 2 Stem Cell Definitions Understanding the switch between ES cell self- renewal and differentiation Stem cells are unspecialized cells Self-renew Inducible fates 14

15 Global regulators of gene expression Adapted from Nature 429: 457 Tbr2+ identifies intermediate progenitor cells VZ Emx Otx1 Fezl Svet1 Tbr2 Cux2 15

16 Pial-directed radial fibers can be visualized on displaced radial glia during mitosis 4A4 antibody (phosphorylated vimentin) Sox2 Outer 16