Page 77 - Human Umbilical Cord Mesenchymal Stem Cells

Biology of Blood and Marrow Transplantation 13:1477-1486 (2007)
Q 2007 American Society for Blood and Marrow Transplantation
1083-8791/07/1312-0001$32.00/0
doi:10.1016/j.bbmt.2007.08.048

Umbilical Cord Mesenchymal Stem Cells: Adjuvants

for Human Cell Transplantation

Robb Friedman,* Monica Betancur,* Laurent Boissel, Hande Tuncer, Curtis Cetrulo, Hans Klingemann

Tufts-New England Medical Center, Molecular Oncology Research Institute, Boston, Massachusetts

*Both authors contributed equally to the research.
Correspondence and reprint requests: Hans Klingemann, MD, PhD, Tufts-New England Medical Center, 750
Washington Street, Mail 245, Boston, MA 02111; Tel: 617-636-6495; Fax: 617-636-3194 (e-mail: hklingemann@
tufts-nemc.org).

Received July 3, 2007; accepted August 30, 2007
ABSTRACT
The Wharton’s jelly of the umbilical cord is rich in mesenchymal stem cells (UC-MSCs) that fulfill the criteria for
MSCs. Here we describe a novel, simple method of obtaining and cryopreserving UC-MSCs by extracting the
Wharton’s jelly from a small piece of cord, followed by mincing the tissue and cryopreserving it in autologous
cord plasma to prevent exposure to allogeneic or animal serum. This direct freezing of cord microparticles with-
out previous culture expansion allows the processing and freezing of umbilical cord blood (UCB) and UC-MSCs
from the same individual on the same day on arrival in the laboratory. UC-MSCs produce significant concentra-
tions of hematopoietic growth factors in culture and augment hematopoietic colony formation when co-cultured
with UCB mononuclear cells. Mice undergoing transplantation with limited numbers of human UCB cells or
1
CD34 selected cells demonstrated augmented engraftment when UC-MSCs were co-transplanted. We also ex-
plored whether UC-MSCs could be further manipulated by transfection with plasmid-based vectors. Electropo-
ration was used to introduce cDNA and mRNA constructs for GFP into the UC-MSCs. Transfection efficiency
was 31% for cDNA and 90% for mRNA. These data show that UC-MSCs represent a reliable, easily accessible,
noncontroversial source of MSCs. They can be prepared and cryopreserved under good manufacturing practices
(GMP) conditions and are able to enhance human hematopoietic engraftment in SCID mice. Considering their
cytokine production and their ability to be easily transfected with plasmid-based vectors, these cells should have
broad applicability in human cell–based therapies.
Ó 2007 American Society for Blood and Marrow Transplantation

KEY WORDS
Cord blood transplantation Mesenchymal stem cell Natural killer cell

INTRODUCTION tion and characterization of MSCs derived from fetal
Mesenchymal stem cells (MSCs) are being increas- tissues, such as the placenta and the umbilical cord, as
ingly developed for indications in the growing field of well as from umbilical cord blood (UCB), have been
regenerative medicine and also for their ability to mod- described [7-11].
During embryogenesis, cells from the hematopoi-
ulate the immune response [1,2]. Recent clinical trials etic progenitor tissue of the fetus, the aortamesogonad
have suggested that bone marrow–derived MSCs region, migrate through the developing cord. It is be-
(BM-MSCs) can aid children born with osteogenesis
lieved that some of these early cells are trapped there
imperfecta [3], improve cardiac function after myocar-
and contribute to the cellular composition of the
dial infarction [4], and treat acute graft-versus-host cord [12]. Inside the cord is a jelly-like matrix material
disease (aGVHD) after bone marrow (BM) transplan- that protects the cord arteries and the vein, initially
tation [5,6]. Given that harvesting of BM-MSCs described by Thomas Wharton in 1656 (‘‘Wharton’s
involves a painful, invasive procedure, alternative sour- jelly’’). Termed umbilical cord MSCs (UC-MSCs),
ces of MSCs may prove more useful. Recently, extrac- these cells have many of the same characteristics as

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