In addition to accomplishing
a haemostatic seal, the platelets present in the PRP contain
many platelet derived growth factors.
PDGF
exists in three forms;
PDGFaa, PDGFbb, PDGFab. PDGF is a very powerful regulatory
growth factor and a sentinel growth factor that begins
nearly all wound healing processes. PDGF's main function
is to stimulate cell replication (mitogenesis) of healing
capable stems and is involved via differentiated osteoprogenitor
cells in the healing of connective tissue-bone and development
of the cellular make-up. PDGF also causes replication
of endothelial cells, causing budding of new capillaries
(angiogenesis).
Transforming
Growth Factor (TGF)
regulates proliferation
and differentiation of multiple cell types. TGF found
in platelets is subdivided into TGFb1 and TGFb2, which
are the more generic connective tissue growing factors
involved with matrix formation influencing osteoblasts
to lay down a bone matrix through the process of osteogenesis.
Cells activated by TGFb1 and TGFb2 include fibroblasts,
endothelial and osteoprogenitor cells, chondroprogenitor
cells and messenchymal stem cells. A chondroprogenitor
cell will further differentiate and produce the matrix
for cartilage. A messenchymal stem cell stimulates mitosis
and provides wound healing cells.
Epidermal
Growth Factor (EGF)
is responsible for
cell differentiation and stimulates re-epitheliation,
angiogenesis and collangenase activity.
Insulin
Growth Factors (IGF-1)
is also important in
wound healing, and stimulates both proliferation and differentiated
function in osteoblasts.
In
summary, platelet derived growth factors:
Increase tissue vascularity
through increased angiogenesis
Are chemotactic for monocytes,
macrophages, and fibroblasts
Enhance collagen synthesis
Increase the rate of epithelial
and granulation tissue production
Enhance osteogenesis
The high concentration
of leukocytes in the buffy coat add an antimicrobial
effect, while wound hemostasis and lymphatic sealing
provide an opportunity to eliminate post-operative
drains and reduce pain
Provides watertight seal
for a variety of interventions
London Perfusion
Science, 5 Great College Street, Westminster, London,
SW1P 3SJ Tel: 07703 182 420 Created
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