0:00
Hello, my name is Shay Soker, and
I'm a professor at the Wake Forest
Institute for Regenerative Medicine.
I'll be talking today
about stem and progenitor
cells from peripheral blood.
0:14
The bone marrow is,
most likely, the source
of stem and progenitor
cells in peripheral blood.
Hemangioblasts are the
embryonic precursors
of the hematopoietic
stem cells, or HSCs,
and they would give rise to the
committed hematopoietic cells.
Bone marrow mesenchymal
cells, or MSCs,
have multi-lineage
differentiation potentials.
Endothelial progenitor
cells, or EPCs,
are probably derived from
hemangioblast precursors
of hematopoietic
stem cells, but they
differentiate into
endothelial cells, or ECs.
My lecture will focus on EPCs and
their role in neo-vascularization
0:58
As a definition, I want to
highlight two processes.
The first is angiogenesis- -
the process of forming of new
vessels from pre-existing
blood vessels.
The second one is vasculogenesis-
- the assembly of capillaries
from endothelial progenitor cells.
And I will discuss
during the lecture,
the physiologic neo-vascularization
and pathologic neo-vascularization.
1:27
The embryonic development of the
vasculature, as I told you before-
- it starts with the
primary hepatoblasts
that differentiates
into angioblasts.
These angioblasts will
further go and differentiate
into endothelial cells to
form the primitive plexus,
and under the induction of other
angiogenic prospectus, which we'll
be discussing later on, they
form the mature vascular system.
Once this vascular system is
formed, it stays quiescent
under another set of growth
factors, one of which
is angiopoietin-1, or ANG-1.
Now, the process of
angiogenesis and vasculogenesis
also occurs during
adult life but is
mostly restricted to angiogenesis.
Upon stimulation
using growth factors
such as angiopoietin-2 and VEGF,
the endothelial cells are activated,
and then they form new vessels.
Recently- - and that's going to
be the topic of this lecture- -
it was shown that the immature
hemangioblasts and angioblasts may
also contribute to adult
neo-vascularization.
