p.1
Tissue Engineering Paradigm
What is the focus of Lecture 2 in the Tissue Engineering course?
Cell Source, Growth, and Differentiation.
p.2
Tissue Engineering Paradigm
What are the key components to consider in the Tissue Engineering Paradigm?
Cells, biocompatible materials, biochemical factors (e.g., growth factors), and biophysical factors (e.g., cyclic mechanical loading).
p.2
Tissue Engineering Paradigm
What role do biochemical factors play in tissue engineering?
They include elements like growth factors that are crucial for cell growth and tissue development.
p.2
Tissue Engineering Paradigm
What is the significance of biocompatible materials in tissue engineering?
They are essential for ensuring that the materials used do not provoke an adverse reaction in the body.
p.2
Tissue Engineering Paradigm
How do biophysical factors influence tissue engineering?
Factors like cyclic mechanical loading can affect cell behavior and tissue formation.
What is the primary role of adult stem cells?
To maintain tissue homeostasis and replace cells lost due to normal turnover, injury, or disease.
p.41
Tissue Engineering Paradigm
What is the role of vascular stem cells in tissue engineering?
They undergo osteogenic differentiation to produce fully-vascularized, architecturally complete bone tissue.
p.41
Applications and Concerns in Stem Cell Research
What conditions are associated with the differentiation of vascular stem cells?
Aortic sclerosis and aortic stenosis.
How can haematopoietic stem cells be alternatively derived?
From blood treated with cytokines, such as G-CSF.
What is the main source for adult stem cells?
Autologous source, but the number is low.
p.6
Cell Types and Functions
What is HeLa?
HeLa is the oldest and most commonly used human cell line.
p.21
Embryonic Stem Cells (ESCs)
Why can't LIF be used for human ESCs?
LIF does not work for human ESCs; they require a different culture method.
p.32
Applications and Concerns in Stem Cell Research
What is the purpose of the in vivo assay repopulation test for HSCs?
To assess recovery of health condition after injection into a lethally irradiated mouse.
p.9
Differentiation and Plasticity
What is extrinsic asymmetry in asymmetric stem cell division?
Regulated orientation of the mitotic spindle retains only one daughter in the stem cell niche, allowing that daughter cell access to extrinsic signals necessary for maintaining stem-cell identity.
p.5
Cell Types and Functions
What are immortalized cells?
Cell lines undergoing transformation that happens spontaneously or is induced by chemical or virus.
p.10
Stem Cell Characteristics
What is the estimated ratio of stem cells in bone marrow?
1 in 10,000 to 15,000 cells.
p.44
Stem Cell Characteristics
What is the ultimate characterization of stem cells?
The formation of viable chimera.
p.21
Embryonic Stem Cells (ESCs)
What factor enables the growth of mouse ES cells in culture without a feeder layer?
Leukemia Inhibitory Factor (LIF).
p.32
Stem Cell Characteristics
Which markers are present in Hematopoietic Stem Cells (HSCs)?
CD34, CD43, CD45RO, CD45RA, CD59, CD90, CD109, CD117, CD133, CD166, and Lin.
What is a drawback of deriving haematopoietic stem cells from bone marrow?
The procedure is invasive.
p.16
Embryonic Stem Cells (ESCs)
What is the morula in embryonic development?
A solid mass of cells resulting from cleavage.
p.19
Embryonic Stem Cells (ESCs)
What is the purpose of the unknown factors produced by mouse feeder cells?
To keep the embryonic stem cells undifferentiated.
p.8
Stem Cell Characteristics
What is self-renewal in stem cells?
It is the process during which one or both daughter cells maintain the stem cell phenotype after division.
p.22
Embryonic Stem Cells (ESCs)
What is the goal of optimizing ESCs culture conditions?
To use a culture condition with only small molecules and without mouse feeder cells.
p.40
Applications and Concerns in Stem Cell Research
What is a major cause of morbidity and mortality in cardiovascular disease?
Impaired blood flow caused by rigidity (sclerosis) and focal narrowing (stenosis).
p.22
Embryonic Stem Cells (ESCs)
What engineering strategy was developed for ESCs culture optimization?
A strategy based on closed-loop optimization.
p.21
Embryonic Stem Cells (ESCs)
What is required for culturing human ESCs?
Mouse feeder cells supplemented with basic fibroblast growth factor (bFGF).
p.22
Embryonic Stem Cells (ESCs)
What is a challenge in determining the best cocktail for ESCs culture?
Deciding the best cocktail for culture conditions.
What types of tissues can Mesenchymal stem cells differentiate into?
Bone, cartilage, fat, and supporting stroma for haematopoiesis.
p.17
Tissue Engineering Paradigm
What is the primary function of muscle tissue?
Contracts to generate movement.
p.23
Embryonic Stem Cells (ESCs)
What enzyme is associated with embryonic stem cells?
Alkaline phosphatase (ALP).
p.12
Stem Cell Characteristics
What does pluripotency refer to in stem cells?
Pluripotent stem cells can differentiate into any of the three germ layers: endoderm, mesoderm, or ectoderm, but cannot produce extraembryonic tissue.
p.38
Differentiation and Plasticity
What did new research reveal about adult stem cells?
They can differentiate across tissue lineage boundaries, sometimes even across germ layers.
p.24
Embryonic Stem Cells (ESCs)
What do embryoid bodies resemble?
Early post-implantation embryos.
p.42
Induced Pluripotent Stem Cells (iPSCs)
What are Induced Pluripotent Stem Cells (iPSCs)?
Adult cells that have been genetically reprogrammed to an embryonic stem cell-like state.
p.40
Applications and Concerns in Stem Cell Research
Why are conventional therapies for atherosclerosis not always effective?
They do not always address the underlying issues of impaired blood flow.
p.21
Applications and Concerns in Stem Cell Research
What concern arises from using animal cells and growth factors in ESC culture?
It creates concerns for future tissue engineering purposes.
p.33
Mesenchymal Stem Cells (MSCs) Characteristics
What types of tissues can MSCs form?
Adipose tissue, cartilage, and mineralization.
p.16
Embryonic Stem Cells (ESCs)
What is the gastrula in embryonic development?
An embryo composed of three tissues: ectoderm, mesoderm, and endoderm.
p.16
Embryonic Stem Cells (ESCs)
What does the Germ Layer Theory state?
Ectoderm, mesoderm, and endoderm are the foundation of the body systems.
p.46
Induced Pluripotent Stem Cells (iPSCs)
What is a potential benefit of using autologous iPS cells?
They reduce the risk of immune rejection.
p.46
Limitations of Differentiated Cells
What risk is associated with genomic insertion in iPS cells?
It may expose the risk of mutations.
p.34
Stem Cell Niche and Microenvironment
What is the stem cell niche?
The microenvironment where stem cells are provided with a sheltering environment.
p.44
Tissue Engineering Paradigm
What does the term 'chimeric mouse' refer to?
A hybrid of creatures, originating from Greek mythology.
What types of cells do adult stem cells generate?
Intermediate cell types, including progenitors and precursors.
p.36
Stem Cell Niche and Microenvironment
In another view, where is the HSCs niche localized?
To the walls of bone marrow blood vessels (sinusoids).
p.20
Embryonic Stem Cells (ESCs)
What is a major challenge in culturing embryonic stem cells (ESCs)?
Maintaining the 'stemness'.
p.47
Embryonic Stem Cells (ESCs)
What is the DOI for the article on synthetic embryos?
https://doi.org/10.1016/j.cell.2022.07.028.
What type of cells are Vascular Mesenchymal Cells?
Adult stem cells derived from bovine artery.
p.43
Induced Pluripotent Stem Cells (iPSCs)
What are induced pluripotent stem cells (iPSCs)?
Somatic cells that are forced to express 4 genes important for maintaining and defining properties of embryonic stem cells (ESCs).
p.26
Applications and Concerns in Stem Cell Research
What are the concerns associated with the use of ESCs?
Immune rejection, purification of differentiated cells, and removal of pluripotent cells.
p.46
Induced Pluripotent Stem Cells (iPSCs)
What is a significant advantage of iPS cells?
They provide an unlimited cell supply.
p.3
Cell Types and Functions
What is the function of Neurons?
Transmission of electrical impulses.
p.25
Tissue Engineering Paradigm
What can be identified in the teratoma formed from embryonic stem cells?
Advanced tissue types of all three germ layers.
p.13
Stem Cell Characteristics
What concept is associated with the Stem Cell Continuum?
It relates to the various stages and types of stem cells.
p.34
Stem Cell Niche and Microenvironment
What are the two main functions of the stem cell niche?
To support self-renewal and produce differentiated progeny.
What does the term 'adult stem cells' generally refer to?
Post-natal stem cells found in cord blood, baby teeth, and placenta.
p.18
Embryonic Stem Cells (ESCs)
What is the purpose of immunosurgery in ESCs isolation?
To isolate the inner cell mass from the blastocyst.
p.18
Embryonic Stem Cells (ESCs)
What is the first step in the immunosurgery process?
Preincubation with an antiserum to label the trophoblasts with antibodies.
p.11
Differentiation and Plasticity
Give an example of induced transdifferentiation in mammals.
The conversion of pancreatic cells to hepatocytes.
What types of cells do Haematopoietic stem cells produce?
Red and white blood cells, and platelets.
p.5
Cell Types and Functions
Why is telomerase activity important in cell lines?
It restores telomerase activity as telomeres are shortened during duplication.
From where can mesenchymal stem cells be isolated in patients undergoing total hip replacement?
Iliac crest or femoral heads.
p.17
Tissue Engineering Paradigm
What is the function of epithelial tissue?
Covers the body, lines cavities, and forms glands.
p.46
Induced Pluripotent Stem Cells (iPSCs)
How do iPS cells address ethical concerns associated with ESCs?
They avoid the ethical concerns by not using embryonic stem cells.
p.46
Limitations of Differentiated Cells
What is a major limitation of iPS cell technology?
The throughput of successfully reprogrammed cells is very low, only 0.01 – 0.1%.
p.17
Tissue Engineering Paradigm
What organs are formed from the endoderm?
Lungs, liver, lining of digestive organs, and some endocrine glands.
p.19
Embryonic Stem Cells (ESCs)
How are mouse feeder cells treated to support ESC culture?
They are mitotically inactivated by irradiation.
p.34
Stem Cell Niche and Microenvironment
What balance does the stem cell niche maintain?
A balance between stem cell quiescence and activity.
p.47
Embryonic Stem Cells (ESCs)
What type of embryos were generated ex utero from mouse naive ESCs?
Post-gastrulation synthetic embryos.
p.9
Differentiation and Plasticity
What is intrinsic asymmetry in asymmetric stem cell division?
The daughter cells are inherently different at the time of division due to asymmetric localization of cell polarity regulators or cell fate determinants.
p.44
Applications and Concerns in Stem Cell Research
What potential advancement may soon be possible with human-pig chimeras?
Generating human organs inside of them.
p.5
Cell Types and Functions
What is a finite cell line?
A cell line with limited proliferative capability.
p.6
Cell Types and Functions
What type of cells are HeLa cells?
Immortalized cells that transformed spontaneously.
p.9
Stem Cell Niche and Microenvironment
What role do extrinsic signals play in stem cell identity?
They are necessary for maintaining stem-cell identity.
p.6
Limitations of Differentiated Cells
What potential issue arises from the use of HeLa cells in laboratories?
Their proliferative capability creates potential contamination for other cell types.
p.40
Differentiation and Plasticity
What can Vascular Mesenchymal Cells do in culture?
Differentiate and self-organize into multicellular structures.
p.18
Embryonic Stem Cells (ESCs)
How does the complement system contribute to the removal of trophoblasts?
The attachment of complement causes cytotoxicity that removes the external layer, leaving the inner cell mass.
p.43
Induced Pluripotent Stem Cells (iPSCs)
What role do c-Myc and Klf-4 play in iPSCs?
They maintain the ESCs phenotype and proliferation.
p.10
Differentiation and Plasticity
What is the process by which one stem cell division leads to many differentiated cells?
Through transit amplifying cells and progenitor cells.
p.17
Tissue Engineering Paradigm
What structures are derived from the ectoderm?
Nervous system, ectodermis, and sweat glands.
p.39
Applications and Concerns in Stem Cell Research
In which journal was the article by Kolf et al. published?
Arthritis Research & Therapy
p.8
Stem Cell Characteristics
How can stem cells divide?
Stem cells can divide symmetrically or asymmetrically.
p.35
Stem Cell Niche and Microenvironment
What is the deterministic model in stem cell division?
The stem cell is determined to divide asymmetrically based on spatial and functional constraints.
p.8
Stem Cell Characteristics
What determines the appropriate numbers of stem cells and differentiated daughters?
The balance between symmetrical and asymmetrical divisions.
p.35
Stem Cell Niche and Microenvironment
What happens to a stem cell as long as the restriction cue is present?
The cell is retained in the space and performs self-renewal.
p.8
Differentiation and Plasticity
What happens during asymmetric cell division of stem cells?
One daughter cell becomes a new stem cell, while the other differentiates into a more specialized cell type.
p.32
Applications and Concerns in Stem Cell Research
What happens to the mouse in the in vivo assay for HSCs?
It receives a dose of irradiation sufficient to kill its blood-producing cells.
p.26
Applications and Concerns in Stem Cell Research
What are some successful applications of embryonic stem cells (ESCs)?
Neurons, cardiomyocytes, hepatocytes, pancreatic beta cells, endothelial cells, blood cells, and chondrocytes.
p.16
Embryonic Stem Cells (ESCs)
What is the embryonic disk?
It is formed by the inner mass of cells of the blastocyst.
p.7
Embryonic Stem Cells (ESCs)
What is a moral concern associated with embryonic stem cells?
Moral objection due to ethical considerations.
p.3
Cell Types and Functions
What is the role of T lymphocytes in the immune response?
Regulation of immune response.
p.23
Embryonic Stem Cells (ESCs)
What are embryoid bodies?
Structures formed by mouse embryonic stem cells in colonies, floating in the culture medium.
p.25
Tissue Engineering Paradigm
What types of tissues can be derived from embryonic stem cells?
Cartilage, bone, neural tissue, glandular epithelium, and ciliated columnar epithelium.
p.5
Cell Types and Functions
What is primary culture?
Cells isolated from tissue and cultured under appropriate conditions until confluence.
p.4
Limitations of Differentiated Cells
What is a limitation of using differentiated cells in tissue engineering?
Limited availability of differentiated autologous cells.
p.6
Cell Types and Functions
From whom is the HeLa cell line derived?
Henrietta Lacks, a patient who died from cervical cancer in 1951.
p.4
Limitations of Differentiated Cells
What is a limitation regarding the proliferative capacity of differentiated cells?
Limited proliferative capacity and biosynthetic activity.
p.18
Embryonic Stem Cells (ESCs)
What does the complement system consist of?
A number of small proteins found in the blood.
p.4
Limitations of Differentiated Cells
How do differentiated cells differ from stem cells in terms of commitment?
Differentiated cells are committed to perform a specific function, while stem cells are uncommitted until they receive environmental signals.
p.31
Differentiation and Plasticity
What tissues can mesenchymal stem cells form?
Enamel, dentin, blood vessels, dental pulp, hepatocyte, and nervous tissues.
Where else have adult stem cells been discovered?
In the epidermis, liver, pancreas, brain, dental pulp, and spinal cord.
What is a recognized source for multipotent stem cells after liposuction?
Fat tissue (adipose stem cells).
p.43
Differentiation and Plasticity
What types of structures can the iPS line 1A2 differentiate into?
Epithelial structures, cartilage with surrounding muscle, glandular structures, and neural tissue.
What is a challenge in working with adult stem cells?
The isolation and identification process is not well defined.
p.46
Limitations of Differentiated Cells
What is a potential consequence of some reprogramming factors in iPS cells?
Tumor formation due to some factors being oncogenes.
p.12
Differentiation and Plasticity
What types of tissues can endoderm differentiate into?
Endoderm can differentiate into the interior stomach lining, gastrointestinal tract, and lungs.
p.38
Differentiation and Plasticity
What was the initial belief about adult stem cells?
Researchers thought adult stem cells could only differentiate into the tissue where they reside.
p.24
Embryonic Stem Cells (ESCs)
What are the three germ layers formed during the differentiation of ES cells?
Ectoderm, mesoderm, and endoderm.
p.11
Differentiation and Plasticity
What is differentiation in the context of tissue engineering?
Differentiation is not just a one-way path; it involves both de-differentiation and differentiation.
p.5
Cell Types and Functions
What happens to primary culture after the first subculture?
It becomes known as a cell line.
p.11
Differentiation and Plasticity
What happens to chondrocytes when cultured in vitro?
They lose their cartilage phenotype, change morphology to a fibroblast-like cell, and stop expressing collagen type II.
p.40
Applications and Concerns in Stem Cell Research
What are conventional therapies for atherosclerosis?
Lipid-lowering medicines.
p.11
Differentiation and Plasticity
What is transdifferentiation?
Transdifferentiation is the switch of a differentiated cell into another differentiated cell, either within the same tissue or into a completely different tissue.
p.37
Stem Cell Niche and Microenvironment
What types of signaling molecules are involved in MSC interactions?
Autocrine, paracrine, and endocrine factors.
p.45
Induced Pluripotent Stem Cells (iPSCs)
What was the outcome of the first generation of iPS cells in forming chimeric mice?
They failed to form chimeric mice.
p.18
Embryonic Stem Cells (ESCs)
What is the normal function of the complement system?
To kill and clear pathogens from an organism.
What is a characteristic of adult stem cells?
They are more committed and found in tissue at a low number.
p.23
Embryonic Stem Cells (ESCs)
What is a characteristic of embryonic stem cells related to cell division?
High levels of telomerase.
p.19
Embryonic Stem Cells (ESCs)
What are embryonic stem cells (ESCs) cultured on?
Mouse fibroblasts feeder cells.
p.24
Embryonic Stem Cells (ESCs)
What happens when embryonic stem (ES) cells are placed in a non-adherent dish?
They spontaneously form cell aggregates resembling early post-implantation embryos.
p.15
Embryonic Stem Cells (ESCs)
What occurs prior to implantation in the uterine wall?
Cleavage and the formation of the blastocyst.
p.14
Tissue Engineering Paradigm
What is the focus of the book 'Tissue Engineering: Principles for the Design of Replacement Organs and Tissues'?
The principles of tissue engineering.
p.37
Stem Cell Niche and Microenvironment
Where are mesenchymal stem cells (MSCs) found?
In the putative perivascular niche (BV, blood vessel).
p.9
Differentiation and Plasticity
What are examples of macromolecules involved in intrinsic asymmetry?
Proteins, RNA transcripts, or other macromolecules.
p.37
Stem Cell Niche and Microenvironment
How do MSCs interact with differentiated cells?
Via cell-adhesion molecules, extracellular matrix mediated by integrin receptors, and signaling molecules.
p.35
Stem Cell Niche and Microenvironment
What does the stochastic model assume about stem cell division?
A stem cell can stochastically switch between asymmetric or symmetric division modes.
p.35
Stem Cell Niche and Microenvironment
In the stochastic model, what can the daughter cells become?
They can be either stem cells or more committed progenitor cells.
p.16
Embryonic Stem Cells (ESCs)
What is formed from the morula during embryonic development?
The blastocyst, which is a ball of cells with an inner cell mass.
What is cord blood banking?
A method of collecting and storing cord blood for potential medical use.
p.45
Induced Pluripotent Stem Cells (iPSCs)
From which types of adult cells have induced pluripotent cells been made?
Stomach, liver, skin, blood, prostate, and urinary tract cells.
p.25
Tissue Engineering Paradigm
What is the purpose of injecting embryonic stem cells into immunodeficient mice?
To characterize in vivo and observe the formation of teratomas.
p.12
Stem Cell Characteristics
What does unipotent mean in the context of stem cells?
Unipotent cells have the capacity to develop or differentiate into only one type of tissue or cell type.
p.41
Stem Cell Characteristics
What is hypothesized about vascular stem cells beyond the accumulation of lipoprotein products?
They undergo osteogenic differentiation.
What are the two different populations found in bone marrow?
Haematopoietic stem cells and Mesenchymal stem cells.
p.37
Stem Cell Niche and Microenvironment
What is the role of integrin receptors in MSC interactions?
They mediate the interaction with the extracellular matrix.
p.17
Tissue Engineering Paradigm
What are the four types of tissue?
Epithelial, connective, muscle, and nervous tissue.
p.10
Differentiation and Plasticity
What do the red pentagons represent in the stem cell diagram?
Final differentiated cells.
p.3
Cell Types and Functions
What do B lymphocytes synthesize?
Antibodies (immunoglobulins).
p.12
Stem Cell Characteristics
What is totipotency in stem cells?
Totipotent stem cells can divide and produce all differentiated cells in an organism, including extraembryonic tissues.
p.12
Differentiation and Plasticity
What types of tissues can ectoderm differentiate into?
Ectoderm can differentiate into epidermal tissues and the nervous system.
p.7
Stem Cell Characteristics
What defines a stem cell?
1) The ability to self-renew (make identical copies of themselves) and 2) The ability to form other cell types (differentiate).
p.7
Stem Cell Characteristics
What are the two main types of stem cells?
Embryonic and adult (or somatic) stem cells.
p.17
Tissue Engineering Paradigm
What role does connective tissue play in the body?
Binds, supports, and protects body parts.
p.17
Tissue Engineering Paradigm
What does nervous tissue do?
Initiates and transmits nerve impulses.
p.25
Tissue Engineering Paradigm
What type of tumor forms from the injection of embryonic stem cells?
A benign tumor called teratoma.
p.20
Embryonic Stem Cells (ESCs)
What method is used for cell dissociation in human ESCs?
Mechanical dissection by a knife.
p.43
Induced Pluripotent Stem Cells (iPSCs)
How are the genes for iPSCs delivered?
Via retroviral introduction.
p.10
Differentiation and Plasticity
How do progenitor cells contribute to cell differentiation?
They can divide many times, giving rise to thousands of fully differentiated cells.
p.12
Differentiation and Plasticity
What types of tissues can mesoderm differentiate into?
Mesoderm can differentiate into muscle, bone, blood, and urogenital tissues.
p.12
Stem Cell Characteristics
What is multipotency in stem cells?
Multipotent stem cells, or progenitor cells, can develop into multiple other cell types.
