2009-ASCB-Press-Book - page 8

T h e A m e r i c a n s o c i e t y f o r C e l l B i o l o g y
News from
The American Society
for Cell Biology
49th Annual Meeting
San Diego, CA
December 5–9, 2009
Umbilical stem cells allow mice
to see through clear eyes
10:00 am, U.S. Pacific Time
Tuesday, December 8, 2009
Winston W.-Y. Kao
University of Cincinnati College
of Medicine
3223 Eden Ave.,
Mail Location 0838
Cincinnati, OH 45267-0838
(513) 558-2802
Author presents
Tuesday, December 8, 2009
11:00 am–12:30 pm
Poster Session 3:
Other Diseases III
Program 1694
Board B73
Exhibit Halls D–H
Cell Therapy of Corneal
Diseases with Umbilical
Mesenchymal Stem Cells
W.-Y. Kao, H. Liu, J. Zhang,
C. Liu
Ophthalmology, University of
Cincinnati, Cincinnati, OH
J.V. Jester
Ophthalmology, University of
California, Irvine, Irvine, CA
M. Sieber, J. Chang
Bionet Inc., Taipei, Taiwan
Using human umbilical stem
cells as an alternative to corneal
transplants clears an experimental
hurdle by opening the cloudy eyes
of a lab mouse
he miracle age of organ transplan-
tation began not with the heart but
with the cornea of the eye in 1905.
More than a century later, the 50,000
corneal transplants performed each year
in the U.S. seem less of a miracle and
more of a standard therapy for severe
corneal injury or disease. Yet the supply
of human corneas for transplantation is
under threat from an unexpected direc-
tion—laser eye surgery to reconfigure the
refractive surface of the cornea. Whatever
it does for eyesight, laser surgery usu-
ally leaves the cornea unsuitable for later
organ donation.
In the face of this growing short-
age comes a successful demonstration
of principle for a radically different ap-
proach to treating corneal damage—
transplanting human umbilical cord
mesenchymal stem cells (UMSCs) onto
the damaged cornea. Winston Kao and
colleagues at the University of Cincinnati
College of Medicine transplanted UMSCs
into the eyes of special knockout mice
genetically engineered to lack the gene
for making lumican. Lumican is a protein
essential for the formation and mainte-
nance of a transparent cornea. Knockout
mice without lumican have thin and
cloudy corneas.
Kao reports that transplanting
human UMSCs into the mouse eyes
significantly improved corneal transpar-
ency and increased the thickness of the
corneal stroma, the transparent middle
layer. The transplanted umbilical stem
cells survived in the mouse corneal stroma
for more than three months, with minimal
signs of graft rejection. In contrast, when
Kao transplanted human umbilical
hematopoietic stem cells, the stem cells
that give rise to all blood cell types, they
rapidly vanished from the mouse corneas,
victims of graft–host rejection.
Kao says that histological and immu-
nofluorescence staining showed that
the transplanted UMSCs could transdif-
ferentiate and assume the appearance
of normal corneal keratocytes. The new
cells expressed critical keratocyte markers
such as keratocan and aldehyde dehydro-
genase, as well as the adhesion protein,
CD34, all with little or no graft reaction.
Having his proof of principle in hand,
Kao believes that UMSC transplants are
well worth pursuing as an alternative
treatment for severe genetic and corneal
diseases. Unlike donated corneas, the
supply of human UMSCs is almost un-
limited, says Kao. They are easy to isolate
from the umbilical cord. Their numbers
can be expanded in cell culture and they
can be stored and quickly recovered from
liquid nitrogen when a patient is in urgent
need of a clear, healthy cornea.
Confocal images of corneas of lumican knockout mice: Panel “a” is the control eye with no treatment; Panel “b”
shows the eye 12 weeks after transplantation of 104 umbilical cord mesenchymal stem cells.
1,2,3,4,5,6,7 9,10,11,12,13,14,15,16
Powered by FlippingBook