1. Manifestation of Novel Social Challenges of the European Union in the Teaching Material of Medical Biotechnology Master’s Programmes at the University of Pécs and at the University of Debrecen Identification number: TÁMOP-4.1.2-08/1/A-2009-0011

2. BIOMATERIALS (1) Dr. Judit Pongrácz Three dimensional tissue cultures and tissue engineering – Lecture 7 Manifestation of Novel Social Challenges of the European Union in the Teaching Material of Medical Biotechnology Master’s Programmes at the University of Pécs and at the University of Debrecen Identification number: TÁMOP-4.1.2-08/1/A-2009-0011

3. TÁMOP-4.1.2-08/1/A-2009-0011 Biomaterials used in tissue engineering Biocompatibility Tissue friendly Surface chemistry Porosity Controlled biodegradation Mechanical properties Drug/bioactive compound inclusion and controlled release Support of ECM formation

4. TÁMOP-4.1.2-08/1/A-2009-0011 I Natural biomaterials I Proteins: Collagen Fibrin SilkPolysaccharydes: Agarose Alginate Hyaluronic acid Chitosan

5. TÁMOP-4.1.2-08/1/A-2009-0011 II Natural biomaterials II Advantages: In vivo source, large quantities available Binding sites for cells and adhesion molecules Biocompatibility grantedDisadvantages: Lot-to-lot variability Potential immune reaction because of impurity Limited range of mechanical propertes

6. TÁMOP-4.1.2-08/1/A-2009-0011 I Collagen I Rich in vivo sources Most studied biomaterial Fibrous structure, unique amino acid composition Binding sites for integrins RGD sites for integrin binding Superior biocompatibility Supports large spectra of cell differentiation as a scaffold

7. TÁMOP-4.1.2-08/1/A-2009-0011 II Collagen II Collagen molecule 300nm long and 1.5nm diameter thick Collagen alpha chain Assembly into microfibril Assembly into mature collagen fibril Aggregation of collagen fibrils to form a collagen fibre

8. TÁMOP-4.1.2-08/1/A-2009-0011 Fibrin Fibrinogen is easily obtained from (human) plasma Application as a hydrogel: addition of thrombin Suitable for supporting ES cell differentiation Differentiated cells can be also cultured in fibrin scaffold Widely used also in combination with other scaffolds Recent applications: cardiovascular, cartilage, bone, neuronal tissue engineering Tissue factor (extrinsic) pathway Contact activation (intrinsic) pathway Tissue factor Common pathway Cross-linked fibrin clot Trauma Va XIIIa XIIXIIa XIXIa IXaIX Thrombin (IIa)Prothrombin(II) Fibrinogen (I) XXaX VIIaVII VIIIa Fibrin (Ia) Damaged surface Trauma

9. TÁMOP-4.1.2-08/1/A-2009-0011 I Silk I Produced within specialized glands of some arthropods Overlapping beta-sheet structure, repeating aa motifs Availability of recombinant analogs are increasing Fibroin SericinBombix mori silk consists of Fibroin and Sericin Excellent mechanical properties, fibroin is biocompatible Bone, cartilage and ligament engineering

10. TÁMOP-4.1.2-08/1/A-2009-0011 II Silk II Chemical modification, like RGD groups enhances Ca 2+ deposition and bone cell differentiation Silk promoted more intensive chondrogenesis than collagen used as a scaffold material for cartilage engineering Very slow degradation, bone tissue replaces the silk scaffold

11. TÁMOP-4.1.2-08/1/A-2009-0011 Polysaccharide-based biomaterials Polymers consisting of sugar monomers Plant (seaweed) or animal origin Careful choice needed because of potential immune reactions Most frequently used as hydrogels Can be injected directly at the site of injury Supports cell growth and differentiation

12. TÁMOP-4.1.2-08/1/A-2009-0011 Agarose Main source: Red algae and seaweed Polysaccharide, Galactose-based backbone Biologically inert, no immune response Stiffness and mechanical parameters can be easily manipulated Used for scaffolding cartilage, heart, nerve tissues Supports SC differentiation Versatile application possibilities

13. TÁMOP-4.1.2-08/1/A-2009-0011 Alginate Polysaccharide from the cell walls of brown algae, acidic compound, cationic salts are used Sodium-alginateSodium-alginate: E-401, food additive, gastronomic use, heavy metal binding, fat binding Potassium-alginate:Potassium-alginate: Emulsifier, stabilizer in food industry Calcium-alginate:Calcium-alginate: Water-insoluble gel-like material Used for: –Enzyme immobilization or encapsulation –Encapsulation of whole cells, isolating them from the immune system

14. TÁMOP-4.1.2-08/1/A-2009-0011 Hyaluronan (Hyaluronic acid) Non-sulfated GAG molecule Hyaluronic acid is a major component of the ECM (hyalinic cartilage, skin) Multiple cell surface receptor binding and cell adhesion sites available Role in wound healing, tissue repair ES cell compatibility: supports ES cell differentiation, survival and proliferation Many tissues contain hyaluronic acid Hyaluronan gels used in nerve, cartilage, skin, adipose TE

15. TÁMOP-4.1.2-08/1/A-2009-0011 Chitosan Derived from the deacetylation of chitin; strongly cationic Commercially derived from crustacean exoskeleton Bondages, wound dressing, enhanced blood clotting

16. TÁMOP-4.1.2-08/1/A-2009-0011 Chitosan in bone TE Chitosan facilitates the differentiation of osteocytes At slightly acidic pH chitosan-Ca- phosphate composite is an injectable gel. At physiological pH it gels anchoring osteocytes Native or collagen-linked chitosan enhances monocytes to differentiate into osteoclasts

17. BIOMATERIALS (2) Dr. Judit Pongrácz Three dimensional tissue cultures and tissue engineering – Lecture 8 Manifestation of Novel Social Challenges of the European Union in the Teaching Material of Medical Biotechnology Master’s Programmes at the University of Pécs and at the University of Debrecen Identification number: TÁMOP-4.1.2-08/1/A-2009-0011

18. TÁMOP-4.1.2-08/1/A-2009-0011 I Synthetic biomaterials I Organic polymers: PGA, PLA, PLGA PEG PeptidesInorganic: Ceramic Metal Hydroxyapathite

19. TÁMOP-4.1.2-08/1/A-2009-0011 II Synthetic biomaterials II High reproducibility Industrial-scale production Easy control of mechanical properties Easy control of degradation rate Shaping is easy Often lack sites for cell adhesion Biocompatibility is often questionable SC compatibility and differentiation supporting is not obvious Immune reactions are possible

20. TÁMOP-4.1.2-08/1/A-2009-0011 Poly-(lactic-co-glycolic acid)PLGA FDA approved scaffold material Degradation rate modulation is available Frequently used in adipose, neural, bone, cartilage TE Supports ES cell differentiation, proliferation, survival Biocompatible No immune reaction Mixed polymer, various ratios are available Degradation products are acidic, therefore may alter cell metabolism

21. TÁMOP-4.1.2-08/1/A-2009-0011 Poly-(ethylene glycol), PEG Commonly used biocompatible polymer PEGylation of proteins: modulation of degradation/absorbtion PEG chemical modification available (e.g. heparin, peptides, RGD motifs Frequently used as a scaffold material in SC, bone, cartilage, nerve, liver, vascular TE RGD peptides, BMP, TGF-  release regulation

22. TÁMOP-4.1.2-08/1/A-2009-0011 Peptide-based biomaterials Short amino acid sequences Self-assembly: ampholitic nature Combining the advantages of synthetic materials and natural scaffolds: –Self assembling structure –Binding sites –Purity and consistent quality IKVAV: neurite outgrowth, sequence from laminin RGD: cellular adherence promotion

23. TÁMOP-4.1.2-08/1/A-2009-0011 Ceramic-based biomaterials Inorganic, formed with heat, porous, brittle Bioactive glass is used as a material for implants Hydroxyapatite (in bone it’s natural) Used in bone tissue engineering only Combination with biopolimers, drug delivery enhanced

24. TÁMOP-4.1.2-08/1/A-2009-0011 Metals Alumina Titanium alloys Bio-inert materials Withstands to continuous mechanical load, e.g. heart valves, joint replacements, dental implants Used in orthopaedic surgery May cause immunological reactions – metal allergy