MST2 L14-25 Questions Flashcards
What best describes one of the cell junctions found in animal tissue?
a. Gap junctions connect to intermediate filaments in neighbour cells
b. Tight junctions anchor actin to the ECM
c. Hemidesmosomes anchor intermediate filaments to the ECM
d. Desmosomes seal the gap between epithelial cells
c. Hemidesmosomes anchor intermediate filaments to the ECM
What is a feature of tight junctions?
a. Claudin and Occludin form heterophillic linkages
b. They allow for the simple diffusion of membrane proteins
c. They are organised by scaffold proteins like E-cadherin
d. They are a meshwork of sealing strands of the transmembrane proteins claudin and occludin
d. They are a meshwork of sealing strands of the transmembrane proteins claudin and occludin
What is a feature of anchoring junctions?
a. They consist of an intracellular plaque that attaches to the cytoskeleton and transmembrane proteins that connect to other cells
b. Desmosomes and Hemidesmosomes interact with actin
c. All anchoring junctions are adherens junctions and interact with actin
d. Hemidesmosomes form a continuous belt below the tight junctions which aligns actin filaments
a. They consist of an intracellular plaque that attaches to the cytoskeleton and transmembrane proteins that connect to other cells
How can epithelial tubes form?
a. Myosin motors cause actin bundles to contract in adhesion belts and the cell narrows at the apex
b. The over expression of E-cadherin causes cells to dissociate from one another and form a tube like structure
c. Excess calcium in cells allows hemidesmosomes to release the ECM and allow tube formation
d. Kinesin carries calcium ions to the site of tube formation and the cells widen at the apex
a. Myosin motors cause actin bundles to contract in adhesion belts and the cell narrows at the apex
Which kind of junction involves classical cadherins?
a. Tight junction
b. Gap Junction
c. Adherens junction
d. Desmosomes
c. Adherens junction
What is not a feature of desmosomes?
a. They connect intermediate filaments between cells
b. They require interactions with A6B4 integrin
c. They distribute tensile forces
d. Connections involves desmocollin
b. They require interactions with A6B4 integrin
Which junction links cells to the basal lamina?
a. Hemidesmosome
b. Tight junction
c. Desmosome
d. Adherens junction
a. Hemidesmosome
Which is a feature of hemidesmosomes?
a. They interact with the sides of cytokeratin filaments
b. They involve the adapter proteins plakoglobin and plakophillin
c. They attach to the ECM via integrins
d. They allow water soluble molecules to pass between cells
c. They attach to the ECM via integrins
What makes up the ECM?
a. Structural proteins such as tenascin
b. Adhesive ligands such as collagen
c. Anti-adhesive ligands such as elastin
d. Adhesive ligands such as laminin
d. Adhesive ligands such as laminin
What helps to regulate apico-basal polarity?
a. Par3/Par6/aPKC complex association with gap junctions
b. A basal crumbs complex
c. Cdc42 and Rac binding the Par3/Par6/aPKC complex at tight junctions
d. Degradation of the scribble complex
c. Cdc42 and Rac binding the Par3/Par6/aPKC complex at tight junctions
What, apart from actin polarisation, can influence epithelial cell polarity?
a. Shutdown of protein trafficiking to the apical, lateral and basal membranes
b. Signalling through gap junctions
c. Continuous, upregulated ion flow
d. Regulated secretion and absorption
d. Regulated secretion and absorption
What does driving snail or twist expression do in epithelial cells?
a. The cells lose all stem cell characteristics
b. Intestinal epithelial stem cells express mesenchymal markers
c. Intestinal epithelial stem cells lose their ability to be epithelial tissue
d. There is an absence of Lgr5 on mammary cells
b. Intestinal epithelial stem cells express mesenchymal markers
• Cytoskeletons of cells are linked in connective tissue and this forms the ECM.
F
• All anchoring junctions interact with actin.
F (actin: adherens, intermediate filaments: hemi and desmosomes)
• Homophillic adhesion and differential expression of different cadherins leads to cell sorting and tissue formation.
T
• Classical cadherins in adherens junctions link to intermediate filaments via catenins.
F (actin)
• Desmosomes interact with the side of cytokeratin filaments and hemidesmosomes interact with the ends of cytokeratin filaments.
T
• A hemidesmosome is a specialised ECM that underlies all epithelia.
F (BL)
• Neural crest cells are more mesenchymal like than neural tube cells.
T
What makes up skin?
a. Keratinocytes are found mostly in the dermis
b. Hair follicles grow from the epidermis
c. Pericytes are unique to the epidermis
d. Epidermis regenerates due to basal keratinocytes
d. Epidermis regenerates due to basal keratinocytes
What is not a function of skin?
a. Tough barrier against pathogens
b. Temperature control
c. Encourage water loss
d. Oil secretion
c. Encourage water loss
What is true about burns?
a. 1st degree burns involve the epidermis and dermis
b. Muscle and bone can be damaged in second degree burns
c. 3rd degree burns involve all three skin layers
d. 1st degree burns only involve the subcutaneous tissue
c. 3rd degree burns involve all three skin layers
What is not involved in culturing human skin epidermal cells?
a. Silver and iron supplements
b. An irradiated feeder layer (Swiss 3T3 J2 embryonic mouse fibroblasts)
c. Medium with cholera toxin, hydrocortisone, EGF, 10% foetal calf serum
d. Keratinocytes expand from the epidermis
a. Silver and iron supplements
What is a problem with current burn therapies?
a. Human cells are needed as feeder layers
b. Animal products, like serum, can carry pathogens
c. Only 10% of epidermal cells from the patient grow in culture
d. The culture skin cells can proliferate and lead to melanoma
b. Animal products, like serum, can carry pathogens
a. need mouse
c. (
What is a feature of CD34?
a. It is a cell surface marker on red blood cells
b. It can be found on haemopoietic stem cells and progenitor cells and hair follicle bulge region
c. Basal and super-basal bulge cells can regenerate hair follicles in the absence of CD34
d. It is unique to skin stem cells
b. It can be found on haemopoietic stem cells and progenitor cells and hair follicle bulge region
What is a feature of skin stem cells?
a. Transit amplifying cells are cycling and mostly basal
b. Early differentiation cells show intermediate long term proliferation
c. Transit amplifying cells are quiescent
d. Keratinocyte stem cells are present in large amounts
a. Transit amplifying cells are cycling and mostly basal
What is a feature of laminin10/11?
a. They repress the growth of stem cells
b. They are localised in the epithelial basement membranes
c. They can aid cell stem cell growth but do not impact tissue regeneration
d. They demonstrate that skin stem cells do not interact with the ECM
b. They are localised in the epithelial basement membranes
Which genes are expressed in the following types of stem cells?
a. Quiescent cells express epidermal differentiation markers
b. Cycling progenitor cells express Wnt inhibitors
c. Early differentiated cells express cell cycle progression genes
d. Cycling progenitor cells express genes for metabolic pathways
d. Cycling progenitor cells express genes for metabolic pathways
What is not a feature of pericytes?
a. They are localised to the epidermis
b. They can differentiates into fat, bone and cartilage
c. They Associate with basal keratinocytes and can promote epidermal cell proliferation from non-stem cells
d. They can restore adhesive structures (hemidesmosomes) and the basement membrane
a. They are localised to the epidermis
• Stem cells are responsible for organogenesis during embryonic and adult life.
T
• Third degree burns are the most painful.
F
• Cellular allografts are harvested from the patient themselves.
F
• Keratinocytes can be harvests and expanded to generate sheets and 3D cultures used to treat burns.
T
• A single haemopoietic stem cell can reconstitute the entire haemopoietic system of a mouse.
T
• Skin stem cells are found in the granular layer and are absent in hair follicles.
F
• Hair follicle epidermal stem cells in mice can be visualised as slow cycling cells in the bulge region.
T
What is a feature of colon epithelium?
a. There are no villi
b. There is an abundance of +4 stem cells
c. There is an absence of crypt based columnar cells
d. Paneth cells act as niche cells
a. There are no villi
What are the differentiated cell types found in intestinal epithelium?
a. Enterocytes secrete mucus
b. Goblet cells secret hormones
c. Enteroendocine cells are absorptive
d. Paneth cells are immune cells
d. Paneth cells are immune cells
How does Wnt signalling influence intestinal stem cells?
a. APC mutants demonstrate decreased Wnt signalling and a loss of CBC stem cells
b. Increased Wnt signalling can result in adenomatous polyps and colorectal carcinoma
c. An absence of Wnt signalling does not impact the intestinal stem cell pool
d. It down regulates Bmi1 markers to encourage +4 stem cell differentiation
b. Increased Wnt signalling can result in adenomatous polyps and colorectal carcinoma
What causes familial adenomatous polyposis?
a. An inactive Wnt signalling pathway
b. A mutation in APC
c. Under expression of Beta catenin
d. Constitutive production of APC
b. A mutation in APC
How can colorectal cancer be linked to stem cells?
a. Stem cells have no role in the development of colorectal cancer
b. When APC is lost in Transit Amplifying cells, rapidly proliferating adenomas develop
c. Knocking out APC in enterocytes leads to small adenomas that don’t progress
d. When APC is lost in CBC stem cells, rapidly proliferating adenomas develop
d. When APC is lost in CBC stem cells, rapidly proliferating adenomas develop
Which statement is correct?
a. Lgr5+ stem cells and Paneth cells do not interact
b. Paneth cells secrete Wnt and Notch ligands and Lgr5+ stem cells express Fzd7 and Notch 1 recptors
c. Lgr5+ stem cells produce daughter cells symmetrically and by independent choice
d. Lgr5+ cells are niche components that directly influence the activity of Paneth cells
b. Paneth cells secrete Wnt and Notch ligands and Lgr5+ stem cells express Fzd7 and Notch 1 recptors
What is evidence that crypt stem cell populations drift to clonality?
a. Confetti mice exhibited crypts labelled with a single fluoro chrome over a period of months
b. Confetti mice Lgr5 stem cells divided symmetrically and non-stochasitocally and always adopted the fate of a GFP labelled transit amplifying cell
c. Confetti mice exhibited villi labelled with a single fluoro chrome over a period of months
d. Confetti mice exhibited crypts and villi labelled with a single fluoro chrome over a period of months
a. Confetti mice exhibited crypts labelled with a single fluoro chrome over a period of months
How do Wnt and Notch signalling regulate intestinal stem cells?
a. Notch signalling causes Lgr5 and wnt expression in stem cells
b. Cells with high levels of delta activate notch and become absorptive
c. Delta-notch signalling results in lateral inhibition between adjacent cells
d. Wnt leads to the expression of lgr5 and notch in stem cells and down-regulation of Delta in Paneth cells
c. Delta-notch signalling results in lateral inhibition between adjacent cells
How does hedgehog and BMP signalling have a role in regulating the intestinal stem cell niche?
a. BMP4 is expressed in the crypt to repress Hh and Wnt signalling
b. Hh and Wnt signals from the crypt lead to BMP4 expression in the villus core
c. Disrupting hedgehog signalling can lead to ectopic crypts forming in the sides of villi
d. BMP4 expression in the villus core up regulates Hh and Wnt expression in the epithelium
b. Hh and Wnt signals from the crypt lead to BMP4 expression in the villus core
How can organoids self-organise into crypts?
a. Due to BMP4 mediated crypt cell induction
b. Organoids swell when exposed to Forskolin and the addition of exogenous wnt influences crypt formation
c. Paneth cells secret wnt which induces neighbour cells to express EphB which repulse cells expressing EphrinB
d. Paneth cells secrete Delta which can degrade Lgr5+ markers and encourage crypt cell differentiation
c. Paneth cells secret wnt which induces neighbour cells to express EphB which repulse cells expressing EphrinB
• The intestinal epithelium is the slowest tissue to regenerate.
F
• Epithelial cell migration from the crypt to vilus takes 10-15 days.
F
• In the stem cell zone model, it is proposed that transit amplifying cells can de-differentiate back to stem cells.
T
• +4 stem cells are marked with Bmi1 and CBC stem cells are marked with Lgr5.
T
• Lgr5 positive cells can only generate enterocytes and goblet cells.
F
• Lgr5+ stem cells can only build crypt villus structures in vitro if a mesenchymal niche is present.
F
• Culture organoids have been used to repair damage caused by colitis in the intestinal epithelium of mice.
T
What is involved in epithelial-mesenchymal transition?
a. Mesenchymal cells are 100% individualistic
b. An extreme example of EMT is epithelial wound healing
c. Morphogenesis is a pathological form of EMT
d. The removal and repair of cells is a normal role of EMT
d. The removal and repair of cells is a normal role of EMT
What occurs during EMT progression?
a. Cell junctions develop as cadherin expression increases
b. Basal lamina adhesion is lost
c. Intersital ECM is degraded
d. Basal lamina is synthesised
b. Basal lamina adhesion is lost
Which family contains EMT transcription factors?
a. Snail
b. Cadherin
c. Myc
d. Sox
a. Snail
Which are features of mesenchymal cells?
a. Up regulation of EcadH, Apico basal polarity, down regulation of proteases
b. Up regulation of basal lamina ECM, front back polarity, down regulation of E cadherin
c. Down regulation of E cadherin, Up regulation of interstitial ECM, front back polarity
d. Up regulation of proteases, up regulation of basement membrane, up regulation of cytokeratins
c. Down regulation of E cadherin, Up regulation of interstitial ECM, front back polarity
What are the types of EMT?
a. Type 1 describes normal morphogenesis and foetal development processes
b. Type 2 describes the development of cancer cells
c. Type 3 describes processes in wound healing, inflammation and fibrosis
d. Type 4 describes processes leading to angiogenesis
a. Type 1 describes normal morphogenesis and foetal development processes
What can occur during solid tissue cancer?
a. Secondary tumours are easily removed with surgery
b. Tumour initiating cells develop into circulating tumour cells
c. EMT can result in cells being resistant to apoptosis
d. Chemotherapy can remove cancer stem cells
c. EMT can result in cells being resistant to apoptosis
What can solid cancer progression resemble?
a. Clonal expansion resembles stem cell progression
b. EMT to MET is resembled by cell proliferation extension
c. ECM alterations resemble stem cell development
d. Differentiation resembles EMT to MET
a. Clonal expansion resembles stem cell progression
What are the CSC models?
a. The dedicated model states that many cells in a cancer population are capable of becoming TIC/CSC
b. The part time model states that the TIC count is always low
c. The dedicated model states that there is a small amount of CSC proportion in the tumour
d. The part time model states that the niche does not influence CSC regression
c. The dedicated model states that there is a small amount of CSC proportion in the tumour
• Mesenchymal cells lack apical basal polarity.
T
• The TIC/CSC proportion of cells in a cancer population capable of initiating a new tumour is very high.
F
• Mesenchymal cell markers are present in CD44high/CD24low cells.
T
• During EMT and in stem cells, E cadherin is up-regulated and wnt signalling is down-regulated.
F
What does not happen during ENS development?
a. Neural crest cells emigrate from the dorsal neural tube
b. The process is independent of the foregut
c. Neural crest cells migrate in a rostro-caudal direction in the gut wall
d. It involves neural crest cells colonising the gastrointestinal tract
b. The process is independent of the foregut
What is not a consideration for using stem cell therapy to treat Hirschsprung disease?
a. The cells must be first expanded in vivo
b. The cells must not induce an immune response
c. There must be appropriate conditions in post natal gut
d. The introduced cells must respond to cover the musculature
a. The cells must be first expanded in vivo
What is not a feature of the ENS that makes it favourable for stem cell therapy?
a. In Hirschsprung Disease, most of the ENS is still ok
b. Neural crest cells can be made from human pluripotent stem cells
c. ENS organises in response to external cues
d. The ENS is still functional when not ‘perfect’
c. ENS organises in response to external cues
What is used to derive enteric neurons from hESCs?
a. BMP4
b. Exogenous neurospheres
c. Sox2, Oct4, C-myc and Klf4
d. Noggin
d. Noggin
What was shown by graft derived neurons in the ENS?
a. The project into circular muscle
b. They proliferate and differentiate but cannot migrate
c. They fire action potentials, but can’t receive synaptic inputs
d. They are dysfunctional in vivo
a. The project into circular muscle
What is Channelrhodopsin (ChR2)?
a. An ion channel expressed in all mammals
b. An algal ion channel that responds to electrical stimulation
c. An ion channel that allows neurons to be excited by light
d. An ion channel used to stimulate non-stem cell derived nerves
c. An ion channel that allows neurons to be excited by light
• In the enteric nervous system, the submucosal plexus is responsible for blood flow and secretion and the myenteric plexus is responsible for peristalsis.
T
• Hirschsprung disease is an acquired disorder where neurons are lost from the distal bowel.
F
• In Hirschsprung disease, 95% of the gut has 100% neuron density and 5% of the gut has 0% neuron density.
T
• Contractions result from inhibitory junction potentials and Relaxations result from excitary junction potential.
F
What is a feature of the distal tip found in C. elegans?
a. It keeps germ cells in a meiosis stem cell like state
b. It down-regulates delta-notch signalling
c. It up-regulates mitosis specific genes
d. It is present in the intestine
c. It up-regulates mitosis specific genes
What is not a feature of differentiation of GSCs in the drosophila ovary?
a. The terminal filament secretes the UPD cytokine
b. BMP repressed BAM in GSCs
c. UPD activates BMP in cap cells
d. As GSCs move away from the niche, BMP signalling is up-regulated
d. As GSCs move away from the niche, BMP signalling is up-regulated
What is not a feature of differentiation of GSCs in the drosophila testis?
a. Once far enough away from BMP signalling, differentiation occurs immediately
b. Hub cells secrete UPD which activates BMP in cyst stem cells
c. BAM is repressed in GSCs due to BMP signalling
d. Differentiation leads to the formation of spermatogonia
a. Once far enough away from BMP signalling, differentiation occurs immediately
What is true about BAM mutants?
a. Loss of bam in the ovary represses proliferation of GSCs
b. Loss of bam in the testis leads to proliferation of spermatogonia
c. Loss of bam in the ovary down-regulates BMP signalling
d. Loss of bam in the testis leads to proliferation of GSCs
b. Loss of bam in the testis leads to proliferation of spermatogonia
What is involved in the division of drosophila intestinal stem cells?
a. They only give rise to more intestinal stem cells
b. They directly divide into enterocytes and enteroendocrine cells
c. They can produce enteroblasts which give rise to specific intestinal cell types
d. The process depends on UPD and BAM signalling
c. They can produce enteroblasts which give rise to specific intestinal cell types
What is a feature of sponges?
a. Cells form tissues and organs
b. Layers contain the same cell types
c. There is extensive neuronal networks and epithelial tissues
d. The cells are arranged loosely and mesenchyme like
d. The cells are arranged loosely and mesenchyme like
What is a feature of a Piwi family protein?
a. They are absent in human haematopoietic stem cells
b. Archeocytes and Choanocytes express one and have stem cell properties
c. It is found in stem cell populations of cnidarian
d. It is unique to choanoflagelletes
b. Archeocytes and Choanocytes express one and have stem cell properties
What is not a feature of plant meristems?
a. They are stem cell populations
b. They contain zones of cell division, elongation, differentiation
c. The meristem is maintained by Wuschel-expressing cells
d. Meristem secretes Clavata3 which increases the size of the Wuschel domain
d. Meristem secretes Clavata3 which increases the size of the Wuschel domain
• C. Elegans can be males or hermaphrodites and the only dividing cells are found in the gonads.
T
• Drosophila females have germ line stem cells found in the ovary.
T
• The loss of APC has no effect in drosophila.
F
What is a trend seen in the source of haematopoietic stem cells?
a. Peripheral blood stem cells are now rarely used
b. Bone marrow is still the preferred source
c. The use of cord blood is increasing
d. iPS derived haematopoietic stem cells are the preferred source
c. The use of cord blood is increasing
What is an example of a clinical trial for novel application of stem cells?
a. Mesenchymal stem cells used to regenerate retinal epithelium after macular degeneration
b. Foetal stem cells used to derive oligodendrocyte precursors in the case of spinal cord injury
c. hESCs used to engineer neural stem cells following stroke
d. Foetal stem cells used to repair damage due to osteoarthritis
b. Foetal stem cells used to derive oligodendrocyte precursors in the case of spinal cord injury
How does the public perceive risks associated with stem cell therapy?
a. 90% believe risks are high
b. 64% are unsure if there are risks
c. 50% are unsure if there are risks
d. 64% believe there are no risks
d. 64% believe there are no risks
What is not a concern of stem cell tourism?
a. Marketing is based on testimonials
b. The treatments are often successful but not linked with existing care
c. Treatments are expensive and invasive
d. One treatment is often marketed as being able to fix multiple conditions
b. The treatments are often successful but not linked with existing care
• The use of haematopoietic stem cells is considered a novel application.
F
What is not a feature of the retina?
a. It contains glia and 6 types of neurons
b. It has a laminated structure
c. The RPE offers a layer of support
d. It originates from haematopoietic stem cells
d. It originates from haematopoietic stem cells
What is true about using iPSC to treat retinal disease?
a. The process has many ethical issues
b. In genetic diseases, the host derived iPSCs have the same mutation that has caused the disease
c. The grafts can be rejected if immunosuppression treatment is not applied
d. The grafts are rarely functional and the use of hESCs is much more efficient
b. In genetic diseases, the host derived iPSCs have the same mutation that has caused the disease
What is a beneficial feature of the retina of lower vertebrates?
a. The retina can be used as a xeno-transplant for humans with macular degeneration
b. The retina can grow in the absence of glial cells
c. The retina can regenerate following damage
d. The retina contains rods, but no cones, yet is still functional
c. The retina can regenerate following damage
How are glial cells significant?
a. They proliferate to aid retina regeneration
b. They are supported by neurons
c. After light induced retinal damage, they stop proliferating to decrease the risk of mutation from inefficient DNA repair
d. Retinal regeneration can only occur when glial cells are prevented from proliferating
a. They proliferate to aid retina regeneration
RPE keeps photoreceptors alive.
T
• When using ESCs to replace lost retinal cells, the age of the donor is not important.
F
• Mammalian glia can de-differentiate but only to a small degree.
T
Haematopoietic stem cells cannot prevent degeneration of the retina.
F
What tissues renew and regenerate?
a. Bone marrow renews conditionally
b. Lung tissue renews continuously
c. Skeletal muscle is non-renewing
d. The brain renews conditionally
c. Skeletal muscle is non-renewing
As differentiation occurs:
a. The probability of quiescence increases
b. Regenerative capacity decreases
c. Proliferative potential increases
d. Linage restrictions decrease
b. Regenerative capacity decreases
Which statement about haematopoiesis is incorrect?
a. The primitive and definitive stages do not overlap
b. The early circulatory system is established during the primitive stage
c. Multipotent stem cells develop in the definitive stage
d. It occurs in extra and intra embryonic tissue
a. The primitive and definitive stages do not overlap
What is true about the transcriptional regulation of haematopoiesis?
a. RUNX1 mutants lack a definitive stage and die from haemorrhage at day 12.5
b. ETV2 regulates late haematopoietic development and the definitive stage
c. SCL mutants have no yolk sac blood islands
d. ETV2 mutants lack yolk sac haematopoiesis and die after 9.5days
a. RUNX1 mutants lack a definitive stage and die from haemorrhage at day 12.5
Which statement about surrogate stem cell assays is correct?
a. Clongenic assays measure the long term reconstitution potential
b. Immunophenotyping measures surface marker expression via FACs
c. Transplantation measures longer term culture initiating cells
d. Liquid culture assay is the slowest process and measures cytokine stimulated colony growth
b. Immunophenotyping measures surface marker expression via FACs
What is not a feature of a niche?
a. Differentiation is inhibited
b. Reversion to stem cell phenotype can occur
c. It can only be influenced by paracrine signalling
d. It involves cell-cell and cell-matrix interactions
c. It can only be influenced by paracrine signalling
• The bone marrow is colonised with haematopoietic stem cells after 10.5 weeks in humans.
T
• RUNX1 is a helix-loop-helix transcription factor critical for haematopoietic development.
F (SCL)
• Mononuclear cells are the same density as nycoprep which allows them to be isolated, enriched and characterised from the bone marrow.
T
• Mouse haematopoietic stem cells are Lin-, CD34+, CD38-.
F
• Human haematopoietic stem cells are Lin-, Sca1+, cKit+.
F
• Analysing proliferative capacity, differentiation capacity and cytokine driven differentiation are examples of in vitro clonogenic assays which have provided information on haematopoietic stem cells.
T
What is correct about autologous and allogeneic transplants?
a. Allogeneic transplants involve a reinfusion step
b. Only autologous transplants require peripheral blood mobilisation with GCSF
c. Both transplants involve steps in collection, processing, cryopreservation and chemotherapy
d. CXCR4 can be up-regulated by the addition of Plerixafor and this aids mobilisation
c. Both transplants involve steps in collection, processing, cryopreservation and chemotherapy
Where in blood vessls are stem cells found?
a. In the intima layer
b. In the adventitia layer
c. Within the endothelium
d. In the ECM of the media layer
b. In the adventitia layer
What does NOT occur during vasculogenesis?
a. Pericytes and recruited and tight junctions form
b. Differentiation of endothelial cells and haematopoietic cells
c. Haemangioblasts are found at extra-embryonic sites and angioblasts are found at intra-embryonic sites
d. Like haematopoiesis, the process relies on a plexus intermediate
d. Like haematopoiesis, the process relies on a plexus intermediate
What is NOT a step in vasculogenesis?
a. Endothelial progenitor cells differentiate into bone marrow
b. Vessel walls are stabilised by the recruitment pericytes, smooth muscles cells and production of ECM
c. Endothelial cells recruited from bone marrow
d. Endothelial cells proliferate and differentiate into mature endothelium
a. Endothelial progenitor cells differentiate into bone marrow
What is NOT a feature of angiogenesis?
a. Pericytes first detach from the vessel wall and endothelial proteases are released and break down the basement membrane
b. After endothelial cells migrate to surrounding interstitium and form buds, branching can occur
c. The process leads to the formation of new blood vessels from circulating endothelial progenitor cells
d. Vessel walls are stabilised by the recruitment pericytes, smooth muscles cells and production of ECM
c. The process leads to the formation of new blood vessels from circulating endothelial progenitor cells
What is a feature of VEGF?
a. It consists of one ligand (VEGFA) that binds a dozen tyrosine kinase receptors
b. Deleting a single VEGF allele in mice results in E9 embryonic lethality due to no blood island formation
c. It’s downstream affects include cell migration, proliferation and survival
d. VEGF binding can be blocked with neutrophillins
c. It’s downstream affects include cell migration, proliferation and survival
What is false about vascular homeostasis?
a. Tissue hypoxia can signal for the production of angiogenic cytokines/chemokines
b. Endothelial progenitor cells proliferate in the bone marrow
c. Homing involves chemotaxis, adhesion and trans-endothelial migration
d. G-CSF and SDF-1 are down-regulated to initiate mobilisation
d. G-CSF and SDF-1 are down-regulated to initiate mobilisation
What are features of late Endothelial progenitor cells?
a. Non-proliferative haematopoietic cells with haematopoietic makers
b. Mature endothelial markers, no haematopoietic markers
c. Proliferative with haematopoietic makers and mature endothelial markers
d. Adherence and spreading takes 7 days, low proliferative capacity
b. Mature endothelial markers, no haematopoietic markers
How can aging impact endothelial progenitor cells?
a. There is impaired homing to sites of vascular injury
b. Mobilisation and migration happens more frequently
c. There is a decrease in inflmamtion and oxidative stress
d. Function is not impaired but the number of EPCs decreases
a. There is impaired homing to sites of vascular injury
• Activated HSC are in the endosteal niche and quiescent HSC are in the perivascular niche.
F
• The abundance of graft versus host immune-rejection as a result of HAS transplantation lead to a temporary stop in bone marrow transplants in 1963.
T
• Bone marrow EPCs in the bone marrow can give rise to circulating EPCs which can give rise to mature endothelial cells in bone marrow.
T
• EPCs are easily characterised due to specific biomarkers and endothelial cell homogeneity.
F
• Neovascularisation is the formation of new blood vessels in tissues or areas of tissue not normally containing them.
T
What is not a physical cell separation method?
a. Hypotonic lysis
b. Immunoblotting
c. Density gradient centrifugation
d. Velocity sedimentation
b. Immunoblotting
What is enrichment?
a. How well the cells of interest are separated from the rest
b. What proportion of cells of interest in the starting population are recovered from the enriched fraction
c. The compromise between purity and recovery
d. How homogenous the separated cells of interest are
d. How homogenous the separated cells of interest are
What is involved in hypotonic lysis?
a. The process eliminates the compromise between purity and recovery
b. Separation is based on size and density
c. Resolution is time dependent
d. Cells of interest do not degrade over time
c. Resolution is time dependent
What does not impact density gradient separation?
a. The cell nucleus : cell endoplasmic reticulum ratio
b. Temperature of the gradient medium
c. Centrifugal variables like cell load
d. The viscosity and pH of the gradient medium
a. The cell nucleus : cell endoplasmic reticulum ratio
What does not influence immunomagnetic cell separation?
a. Antibody affinity
b. Bead : cell ratio
c. Antibody specificity
d. Rate of sedimentation
d. Rate of sedimentation
What does forward scatter measure?
a. Nucleus: cytoplasm ratio
b. Cell structure and complexity
c. Antibody binding affinity
d. Cell size
d. Cell size
What does side scatter measure?
a. Nucleus: cytoplasm ratio
b. Cell structure and complexity
c. Antibody binding affinity
d. Cell size
b. Cell structure and complexity
How is fluorescence detected in flow cytometry?
a. The dichroic filter selectively passes light of narrow colour range and reflects others
b. The mirror selectively passes some light while rejecting others
c. The bandpass filter reflects blue and green light
d. The laser emits red and orange light
a. The dichroic filter selectively passes light of narrow colour range and reflects others
What is NOT a strength of flow cytometry?
a. It accurately describes a cell population without the need for controls
b. Information about multiple properties of a cell can be gained simultaneously and in real time
c. It can map temporal changes in cellular parameters
d. Rare cell populations can be identified and isolated
a. It accurately describes a cell population without the need for controls
What is not a limitation of flow cytometry?
a. The cells need to be prepared as a single cell suspension
b. Resolution, enrichment and recovery are low
c. The incidence of the target cell influences the process
d. The quality of separation depends on the quality of the reagents
b. Resolution, enrichment and recovery are low
• Stem cells are the most abundant cells in bone marrow.
F
• Cells with a small nucleus : cytoplasm ratio are of low density.
T
• In velocity sedimentation, the rate of sedimentation is mostly determined by cell size.
T
• Lymphocytes demonstrate higher forward and side scatter than eosinophils.
F
• A flow cytometry reading from 2 lasers and 2 flurochromes has higher resolution than one from 1 laser and 2 flurochromes.
T
• Stem cell markers are unique to stem cells and used to define stem cells via flow cytometry.
F
Which method would NOT be used to define mammary stem cells?
a. Limiting dilution assays
b. Transplantation to demonstrate the multilinage differentiation capacity of stem cells
c. In vitro linage tracing
d. Fractionation by flow cytometry using cell surface markers
c. In vitro linage tracing
How was self-renewal shown in Lin- CD24+ CD29hi cells?
a. Serial transplantation studies
b. Bipotent exclusion
c. In vivo linage tracing
d. B-gal assay
a. Serial transplantation studies
How do ovarian hormones influence stem cell activity?
a. Depriving the hormones increases MaSC activity
b. The MaSC pool increases during pregnancy
c. Aging leads to a decrease in MaSC function
d. Excess hormone levels decrease MaSC function
b. The MaSC pool increases during pregnancy
What is RANKL?
a. A ligand that leads to stem cell expansion
b. A luminal progenitor upregulated in breast cancer
c. A compound secreted from the alveolar myoepithlium
d. A steroid hormone that signals stem cell differentiation
a. A ligand that leads to stem cell expansion
The transcription factor GATA3:
a. Is dispensable in the process of luminal cell differentiation
b. Only regulates mammary gland development in the embryo
c. Influences development, cell fate and differentiation
d. Is a master regulator of the RANK pathway
c. Influences development, cell fate and differentiation
What is correct about BRCA-1 mutations?
a. Luminal progenitors exhibit factor-independent growth
b. Colony forming ability is damaged
c. The mutation directly impacts stem cell activity (no, progenitor)
d. Luminal progenitors only proliferate in the presence of growth factors
a. Luminal progenitors exhibit factor-independent growth
What best describes how APC can link to tumour formation in the gut?
a. Tumours arise when APC is deleted in transit amplifying cells
b. Tumours arise when APC is up-regulated in stem cells
c. Tumours arise when APC is deleted in stem cells
d. Tumours arise when APC is deleted from stem cells and transit amplifying cells
c. Tumours arise when APC is deleted in stem cells
What is NOT a feature of cancer stem cells?
a. They are subsets of tumour cells that can self-renew and generate tumour cells
b. They are the same as the ‘cell of origin’
c. They do not necessarily originate from transformation of normal stem cells
d. They can be demonstrated through serial transplantation experiments
b. They are the same as the ‘cell of origin’
• During pregnancy, the breast epithelium can expand 25 fold.
T
• Confetti is a multicolour cre reporter that allows one cell to fluoresce many colours.
F
• Only mouse MaSCs lack receptors for the ovarian hormones oestrogen and progesterone.
F
• Unlike notch signalling, Wnt signalling is essential for the self-renewal of MaSCs.
T
• CD61 cells are 20-fold enriched for CSCs.
T
Where do haemopoietic stem cells arise from?
a. mesoderm
b. visceral endoderm
c. definitive endoderm
d. extoderm
a. mesoderm
