Human Umbilical Cord Blood Progenitors: The Potential of These Hematopoietic Cells to Become Neural

Ning Chen^a^,b, Jennifer E. Hudson^a^,b, Piotr Walczak^a^,b, Iwona Misiuta^a^,b^,f, Svitlana Garbuzova-Davis^a^,b^,f, Lixian Jiang^a^,b^,d, Juan Sanchez-Ramos^a^,c^,f^,h, Paul R. Sanberg^a^,b^,e^,f^,g, Tanja Zigova^a^,b^,c^,f, Alison E. Willing^a^,b^,d^,f^,g

^a Center of Excellence for Aging and Brain Repair and
^b Departments of Neurosurgery,
^c Neurology,
^d Anatomy,
^e Psychiatry,
^f Pharmacology and Therapeutics, and
^g Pathology, University of South Florida, College of Medicine, Tampa, Florida, USA;
^h James A. Haley VA Hospital, Tampa, Florida, USA

Key Words. Human • Umbilical cord blood • Stem/progenitor cell • Multipotential differentiation • Hematopoietic and neural antigens • Neuropoiesis

Correspondence: Ning Chen, M.D., Center of Excellence for Aging and Brain Repair, Department of Neurosurgery, University of South Florida, College of Medicine, 12901 Bruce B. Downs Blvd. Tampa, Florida 33612, USA. Telephone: 813-974-7515; Fax: 813-974-3078; e-mail: nchen1{at}hsc.usf.edu

The mononuclear fraction from human umbilical cord blood (HUCB)contains a significant number of stem/progenitor cells thatin theory could be come any cell in the body, including neurons.Taking into consideration that transdifferentiation would bea very rare event and also knowing that overlapping geneticprograms for hematopoiesis and neuropoiesis exist, we undertooka characterization of the HUCB mononuclear fraction, includinganalysis of cellular subpopulations and their morphology, cellviability, proliferation, and expression of neural and hematopoieticantigens. Two cell populations were apparent—adherentand floating fractions. The adherent fraction was mainly lymphocytes(~53%) expressing hematopoietic antigens. Upon replate, thefloating population had many cells that expressed stem cellantigens. More of the cells in this subfraction expressed neuralproteins. Neurotrophin receptors trkB and trkC were presentin both cell fractions, although expression was higher in thefloating fraction. Our initial characterization suggests thata subpopulation of cells exists within the HUCB mononuclearfraction that seems to have the potential to become neural cells,which could then be used in the development of cell-based therapiesfor brain injuries and diseases.