Nanotechnology in vascular tissue engineering: from nanoscaffolding towards rapid vessel biofabrication : Nanotechnology in vascular tissue engineering: from nanoscaffolding towards rapid vessel biofabrication Vladimir Mironov, Vladimir Kasyanov and Roger R. Markwald Bioprinting Research Center, Department of Cell Biology and Anatomy,
Medical University of South Carolina, 173 Ashley Avenue, Charleston, SC 29425, USA
Mohana Marimuthu
200840090
Overview : Overview Introduction
Nanotechnology
- based control of cell behaviour
- in bioengineering of athrombogenicity
Nanostructuralized biomimetic vascular scaffolds
Magnetic force driven vascular tissue engineering
Introduction : Introduction Bioreactor based – expensive, non automated
Requirements of vascular graft:
Should prevent - thrombosis
- vascular
intimal
thickeneing
- aneurysm
Approaches - solid scaffold
- a hydrogel
- cell sheet
Slide 4: Nanostructuralized scaffold – mimic ECM
Hydrogel – growth factors and ECM peptides – cell and tissue differentiation
Nanotechnology – bioreactor free vascular tissue biofabrication
Control of cell behaviour : Control of cell behaviour Parameters of Biomaterials
ECM ligands/growth factors –
cell differentiation, maturation
ligand density – cell
behaviour – FRET
Archeitectures
Porous Nanofibres Hydrogels
Solid scaffold
Cell differentiation and cell behaviour
Slide 6: Centrifugal casting technology – solid scaffold + biofabrication of nanopatterned hydrogel
Periodic mechanical stretching of cell membranes – magnetic nanoparticles – control cell fate
Bioengineering of Athrombogenicity : Bioengineering of Athrombogenicity 3 strategies
– immobilization of athrombogenic molecules
acellular thromboresistant nanosurfaces – immobilization of molecules – enhance
endothelialization
– enhancement of endothelialization – iron oxide
nanoparticles or magnetic nanobeads – labelled
endothelial cells
Slide 8: Amphiphilic lipid – like lumenal surfaces – athrombogenic phospholipid polymer
Immobilization of CD34 antibodies – post implantational in-vivo endothelialization
Nanocomposite bioactive peptides – endothelial monolayer by circulated progenitor cells
Nanostructuralized biomimetic vascular scaffolds : Nanostructuralized biomimetic vascular scaffolds Fabrication
1. Phase seperation 2. Electrospinning
# nanofibers – size = natural ECM # mimic diameter- collagen fibrils of ECM
# macropore structures # Collagen & elastin + synthetic polymers
centrifugation/ vacuum - scaffolds
rotation technology # Nanofiber meshwork cell attachment
Spreading migration
# one step fabrication integrated with
living cells
Slide 11: 3. Self assembly
Collagen – structural component ECM – capable of self assembly
# cross linking – 3 POG – disulfide
# Chemical ligation – POG larger polymers – heterotrimer
# heterotrimer – electrostatic interaction - stability
Elastin – extensibility
# Tropoelastin, elastin like polypeptides, recombinent
polypeptides - mechanical property
# low productivity, high cost
Magnetic force driven vascular tissue engineering : Magnetic force driven vascular tissue engineering Iron oxide nanoparticles – cells – by endocytosis – desirable location
Cells labelled with magnetic microbeads – endothelium – driven by magnets
Magnets – cell feeding, cell adhesion and monolayer assembly -
cell retention
Slide 14: Cell sheet technololgy
Challenge
- undesirable cell activation
by nanoparticles
- intimal thickening
Organ printing technology
– robotic biofabrication of
intraorgan vessels –
vascular spheroids fused
with tissues
Conclusion : Conclusion Overcome unsolved problems
Bioreactor free methods
Inexpensive
Less time consuming
Potential of nanotechnology – cost effective tissue engineered products
Slide 19: Thank you