Bleed First

Harvest Later

Arjan van den Hil

European Sales Manager

Leipzig, Dezember 18, 2006

„Blut ist ein ganz besonderer Saft!"

Mephisto in Faust

Goethe 1808

Früher wurde das Blut als Sitz der Seele und des Lebens angesehen.

Blood

Blood Components

Human blood consists of 22% solids and 78% water. Its different components are plasma (with all the different blood cells), fat globules, chemical substances (proteins, carbohydrates, hormones, etc.) and gases (oxygen, nitrogen, carbondioxide, etc.)

circulation

spleen

Destruction/removal(spleen, liver)

Production(bone marrow)

platelet countthrombopoietin

70%

30%

Platelets

Wound Healing & Bone Regeneration

When an injury occurs,

platelets attach to the

connecting tissue.

The platelets form a loose

plug and are activated by

thrombin.

Thrombin converts

fibrinogen into fibrin.

The Healing Process: The Role of Platelets

A fibrin matrix is formed, which finally results in a blood clot.

Platelets are releasing growth factors and cytokines

The Healing Process: The Role of Platelets

• Haemostasis– Primary haemostasis– Secundary haemostasis (coagulation)

• Inflammation• Antimicrobial host defence• Wound and/or bone healing, through the

release of growth factors and other mediators

Platelet Functions

+ Thrombin activation

Platelets in rest

Platelets activated

Activation of Platelets: Release of Growth Factors and Cytokines

Activation of Platelets: Release of Growth Factors and Cytokines

• PDGF-AA,BB, AB• TGF-1, 2• VEGF• EGF• bFGF• IGF-I• PD-ECGF• HGF• Osteocalcin• Fibronectin• Fibrinogen• Platelet Factor 4• P-Selectin• Ca2+

• Connective-tissue activating peptide III

• Lipoxygenases• Antiplasmin• Histamine• EPEA• LMW-EMA• HMA-EMA• 12-HETE, 15-HETE• PGE1, PGE2, PGA2, PGJ2, PGF1a,

PGF2a• Serotonin• ADP

Growth Factors and Cytokines in Platelets and White Blood Cells

VEGF

PDGF

FGF

Growth Factor Effects: Angiogenesis

PDGF

TGF-

IGF

Growth Factor Effects: Chemotaxis

TGF-bPDGFEGF

Growth Factor Effects: Mitogenesis

TGF-

Growth Factor Effects: Differentiation

Role of Growth Factors

• PDGF– Stimulates cell replication– Promotes angiogenesis– Promotes epithelialisation– Promotes granulation tissue formation

• TGF– Promotes formation of extracellulair matrix– Regulates bone cell metabolism

• VEGF– Promotes angiogenesis

• EGF– Promotes cell differentiation– Stimulates re-epithelialisation, angiogenesis and collagenase

activity• FGF

– Stimulation of angiogenesis– Promotes proliferation of endothelial cells

and fibroblasts

• Serotonin– Vasoconstriction, increased capillary permeability

• PDGF– Chemotaxis, vasoconstriction, SMC proliferion,

activation of monocytes and neutrophils• -TG

– Neurophil recruitment• TGF-

– Chemotaxis, inhibits neutrophil apoptosis, fibroblast proliferation

Role of Inflammatory mediators

• Toxic O2 metabolites (e.g. O2-, H2O2, OH-)

– All are potent antimicrobial activity

• Antimicrobial peptides (e.g. PF4, PBP, CTAP-3, NAP-2, RANTES, TB-4, FPA, FPB)

• Chemotactic receptors (e.g. C3a, CCR, C5a, thrombocidins)– Involved in guiding platelets towards sites of microbial infection

– Platelets are the first cells to arrive at a site of infection!

Role of Antimicrobial Proteins in Host Defence

Role of Growth Factors in Fracture Healing

Haemostasis 1 d Coagulation CascadeFibrin Matrix Formation

PDGFFGFTGF

Inflammation 1- 4 d Leuco’s macrophage infiltrationIncreased vasodilatation & permeability

TGF FGFPDGF IL-1EGF TxA2

Proliferation 4 d – 3 wk Matrix productionNeovascularizationEpithelialization

FGF TGFPDGF EGF PDAF

Remodelling 3 wk – 2yr Collagen deposition – degradationStable scar formation

TGF PDGFFGF TIMP

Role of Growth Factors in Wound Healing

• Vascularisation: VEGF and bFGF– Asahara et al. Circulation. 92:365. 1995.

• Migration: PDGF and TGF- – Lind M. Acta Orthop. Scand. Supp. 283:2. 1998.

• Proliferation: PDGF, TGF-, and EGF– Slater et al. J. Orthop. Res. 13(5):655. 1995.

• Differentiation: FGF, TGF-, and IGF – Kasperk et al. Growth Factors. 3:147. 1990.

Synergistic Action of Growth Factors

Wound Healing & Bone Regeneration: Role of Platelets

Platelet Degranulation