: The corneal stroma is being increasingly recognized as a repository for stem cells. Like the limbal and endothelial niches, stromal stem cells often reside in the peripheral cornea and limbus. These peripheral and limbal corneal stromal cells (PLCSCs) are known to produce mesenchymal stem cells in vitro. Recently, a common corneal stromal and epithelial progenitor was hinted at. This study aims to examine the stem cell potential of corneal stromal cells and to investigate their epithelial transdifferentiation ability
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1. Mesenchymal and epithelial differentiation ability of
corneal stem cells Peyman Ghoraishizadeh (PHD candidate) Laboratory
of Stem Cells and nano-regenerative medicine, University of Los
Andes
2. Corneal Blindness is a visual impairment that occurs from the
cornea becoming clouded, scarred or any other infection that
ultimately affects the transparency of cornea, making a person
blind. Surgical treatment is faced two problems A) donor shortage
B) immune rejection Alternative solution Stem cell based therapy 3.
Limbal stem cell Corneal and limbal epithelium is supported by a
mesenchymal stroma , which contains cells conven- tionally known as
keratocytes. These cells maintain corneal stromal transparency at a
structural level by producing collagen lamellae and proteoglycans,
including keratocan, decorin, lumican, and mimecan . 4. HYPOTHESIS
Peripheral and limbal corneal stromal cells (PLCSCs) can produce
mesenchymal stem cells so can be used for corneal blindness
therapy. 5. OBJECIVES To isolate PLCSCs and its different types of
subpopulations To study ability of produce MSCs from PLCSCs To
compare effects of media on stem cells properties and
differentiation capacity 6. Methodology PLCSCs were grown in
traditional Dulbecco modified Eagle medium (DMEM)- based keratocyte
culture medium and an M199-based medium and analyzed for a profile
of cell-surface markers by using flow cytometry and differentiated
into mesenchymal phenotypes analyzed with quantitative polymerase
chain reaction (qPCR) and histologic staining. PLCSCs in M199 were
subsequently divided into subpopulations based on CD34 and CD105
expression by using fluorescence- activated cell sorting (FACS).
Subpopulations were characterized by marker profile and mesenchymal
differentiation ability. Both whole PLCSCs and subpopulations were
also cultured for epithelial transdifferentiation 7. Effect of
culture medium on percentage of PLCSCs expressing CD105 and CD34 8.
PLCSCs cultured in MM and KM were analyzed for cell-surface markers
at P3. Subpopulations (A: CD34+CD105+, B: CD34-CD105+, C:
CD34-CD105-) Table 1 Cell-surface m a r k e r p r o f i l i n g of
P L C S C s and i s o l a t e d s u b p o p u l a t i o n s for I S
C T c r i t e r i a and a d d i t i o n a l m a r k e r s C e l l -
s u r f a c e Mean % of positive cells cultured in Mean % of
positive cells in s u b p o p u l a t i o n m a r k e r s MM KM A B
C I S C T Ppsitive criteria ( CD73 95%)1 97.13 0 . 8 1 82.47 2 . 7
3 97.13 0 . 8 1 64.00 4 . 0 0 73.00 3 . 0 0 CD90 98.13 2 . 7 1
99.97 0 . 0 6 99.47 0 . 4 0 99.97 0 . 0 6 97.67 1 . 5 3 CD105 96.67
1 . 5 3 21.33 2 . 0 8 72.00 6 . 0 0 50.00 1 0 . 0 0 46.67 2 0 . 8 2
I S C T negative c r i t e r i a (
