Tissue engineering Flashcards
What is regenerative medicine?
A field of medicine devoted to treatments in which stem cells are induced to repair damaged or destroyed cell populations or tissues.
To study stem cells that are induced to repaired damaged/destroyed cell populations or tissues, tissue engineering can be used.
For tissue engineering, 3 factors are important. Name these
- The scaffold (i.e. on what soil are the stem cells and tissue grown)
- The cells used (i.e. the seed)
- The inducing factors used to grow/sustain the cells (i.e. fertilizer)
For the use of tissue engineering, there are different biomaterials that can be classified based on certain characteristics. What classifications can be made (name three categories)?
- Degradibility (biostable or biodegradable)
- Interaction with the organism (bioinert, bioactive, bioresorbable)
- Chemical nature (polymers, metals, ceramics, composite, natural)
For the use of tissue engineering, there are different biomaterials that can be classified based on certain characteristics. One of these classifications is the degradability, where the biomaterial can be biostable or biodegradable. What is meant with this?
- Biostable → material that maintains its physical and chemical integrity in the biological environment.
- Biodegradable → substance that can undergo decomposition or chemical transformation due to specific actions of the organism.
For the use of tissue engineering, there are different biomaterials that can be classified based on certain characteristics. One of these classifications is the interaction with the organism, where the biomaterial can be bioinert, bioactive or bioresorbable. What is meant with this?
- Bioinert → material that once placed in the human body has minimal interaction with its surrounding tissue.
- Bioactive → material that has the effect on or elicits a response from living tissue, organisms, or cells.
- Bioresorbable → material that degrades safely within the body, without inducing undesirable effects or toxic reactions.
What is an important determinant for the choice of biomaterial? And name factors that influence this determinant.
The directed cell behavior that is influenced by physical factors such as:
- wettability (hydrophillic or hydrophobic)
- Surface energy
- Micro- and nanotopographic properties (grooves)
- Stiffness
Name an example of how the topography of the biomaterial can be optimized.
By using a 3D biopolymer printer
After the production of the biomaterial (e.g. 3D biopolymer printing) for bone cell modeling. What can be the first step to generate a model?
Start cell proliferation and collagen deposition to generate the basis of the cell model.
After the primary bone cell model is generated (so 3D printing of the biopolymer and initiation of cell proliferation and collagen deposition), what can be studied?
- The seeding and proliferation efficiencies of the bone cells
- The osteogenic marker profile
- What are scaffolds?
- What are cell-seeded scaffolds?
- What are bioprinted scaffolds?
- Scaffolds provide the structural support for cell attachment and subsequent tissue development.
- Cell-seeded scaffolds is where the the cells in a cell suspension are placed/injected over the scaffold. So this means there is less specificity and less potential to create a microenvironment, that is the case for bio-printed scaffolds.
- Bio-printed scaffolds is where cells, growth factors and biomaterials are combined to create a microenvironment in which cells can grow and differentiate in tissue structures.
The viability and retention of cells in a cell-seeded and bioprinted scaffold are studied.
What difference can be found when comparing both scaffolds regarding the viability and retention?
- Cell retention → the bioprinted scaffold has a significantly increased cell retention compared to the cell-seeded scaffold.
- Cell viability → the cell-seeded scaffold has a significantly higher cell viability compared to the bioprinted scaffold.
Next, the cell proliferation and collagen deposition of the cell-seeded and bioprinted scaffold are studied.
What difference can be found when comparing both scaffolds regarding the cell proliferation and collagen deposition?
- Cell proliferation → the number of cells in the cell-seeded scaffold is significantly increased compared to the bioprinted scaffold.
- Collagen deposition → no significant difference
Next, the alkaline phosphatase activity of the cell-seeded and bioprinted scaffold are studied.
What difference can be found when comparing both scaffolds regarding the alkaline phosphatase activity?
The cell-seeded scaffold has a significantly higher alkaline phosphatase activity.
What other factors are an important determinent for choice of biomaterial, besides the physical factors of directing cell behavior?
Chemical factors such as the biological binding sites and the release of products.
What are inducing factors?
Growth factors involved in osteochondral differentiation of mesenchymal stem cells.
Explain the definition of:
- allogeneic therapy
- autologous therapy
- Allogeneic therapy → A procedure in which a patient receives healthy stem cells from a donor to replace their own stem cells that have been destroyed by e.g. treatment with radiation or high doses of chemotherapy.
- Autologous therapy → An intervention that uses an individual’s cells or tissues, which are processed outside the body and reintroduced into the donor.
Name advantages and disadvantages of autologous and allogeneic stem cell therapy.
