Tissue Engineering approach
2 D in vitro cell expansion/differentiation
Scaffold seeding
biopsy
3 D graft culture
implantation
Scaffold obtaining
transport
Limitations
in vitro cell culture
• sterility risks• just in time with scheduled operative intervention
• cell transformation• oncogene activation• sterility risks• qualitative and functional changes
graft transport
biopsy •cell are patient property• cellular protocol can not be standardized
Current tissue engineering products are too expensive and risky from a manufacturing point of view
Time consuming2/3 weeks to obtain graft
significant costs
Ideal solution
The whole process should be ideally done intraoperatively eliminating the need of cell
transportation and manipolation
The manufacturing of the graft should be done within
minutes to make any tissue of choice
Bionic Tissue Engineering (BiTE)
Permissive factors
Trauma cytokines, such as IL-6, IL-1β and TNF-α
To enhance the activaction of a permissive situation of wound healing
Recruitment factors
To increase the number of stem cells both in situ and in peripheral circulation
Intraoperativatively can be used alternatively to in situ loading of the graft with prepared stem cells
Granulocyte-macrophage colony-stimulating factor (GM.-CSF) Granulocyte colony-stimulating factor (G-CSF)
Boosting factors
To enhance remodelling, reduce inflammation and activate stem cells to propagate and to protect against ischemia
Erythropoietin (Epo)
Erythropoietin (Epo)
The mRNA expression profile of the erythropoietin receptor (Epo R) and of the tissue protective submit of the erythropoietin receptor (β-CR) in different mouse tissues. GAPDH was used as a housekeeping gene.
Many tissues (including skin) express erythropoietin receptors and the tissue protective submit of the erythropoietin receptor
We decide to use it as an “enhancing” factor in regeneration process
Human dermally derived stem cells (FmSCs) proliferation
Potential role of erythropoietin in acute and chronic wounds
Results indicated both an inhibitory role of EPO in the absence of cytokines (late phase of trauma) and a supportive, boosting activity of
EPO in the presence of trauma cytokines (as IL-6).
complete and stable reepithelialization of the split-thickness skin graft donor site achieved seven days after the operation
topically treated with EPO
local treatment sessions with EPO
granulation tissue formation was obtained and provided an highly vascularized wound bed for successful split-thickness skin grafting.
It is possible that in trauma, EPO ceases its inhibitory role and reverts to a clinically relevant boosting function.
EPO may be an important therapeutic tool for the topical treatment of acute and chronic wounds.
Commitment factors
To control shifting of stem cells towards a commitment
TGF has been by us used to control in vivo differentiation towards cartilage rings to
achieve long term sustainability
If a co-stimulation occurs in the presence of an appropriate scaffold, the cells are triggered to achieve a strong and high
quality remodelling activity
The BiTE concepts
Remodelling activity is better, faster and more tightly controlled than in any in vitro activity