L7 Stem Cell Therapies Flashcards
(48 cards)
What are stem cells?
Undifferentiated cells that are capable of self-renewal and have the potential to differentiate into various cell types
Which are more potent: embryonic or adult stem cells?
Embryonic stem cells (pluripotent)
Most valuable source of embryonic SCs?
Amniotic fluid
Blood from umbilical cord consists of which stem cells?
Haematopoietic and mesenchymal SCs
Which are more potent: haematopoietic or mesenchymal stem cells?
Haematopoietic
Most frequently used source of mesenchymal SCs?
Bone marrow
Where do stem cells come from?
- amniotic fluid
- human umbilical cord
- bone marrow
- adipose tissue
First generation stem cells
- Haematopoietic (multipotent)
- Mesenchymal (multipotent)
Most commonly used stem cell type
HSC
Bone marrow transplants containing __ have been used to treat haematological cancers.
HSCs
Advantage of MSCs
Much easier to isolate and produce a higher yield compared to other SCs
What properties do MSCs possess?
- immunomodulatory
- anti-inflammatory
- angiogenic
- anti-apoptotic
- trophic
Mesenchymal stem cell therapy used in Europe for treating fistulising Crohn’s disease
Alofisel
Second generation stem cells
- Embryonic
- Induced pluripotent
Examples of embryonic stem cell therapies
- Pluripotent derived retinal pigment epithelium to treat age-related macular degeneration
- Oligodendrocytes for spinal cord injuries
How are iPSCs formed?
When the adult cells are cultured with embryonic SCs, forming new cells with SC-like properties
What may occur as a result of the reprogramming process to iPSCs?
Chromosomal abnormalities
2 categories of next generation stem cells
- Use as delivery vehicles for therapeutic drugs
- Use as enhanced therapeutic agents themselves
Tools to create next generation stem cells
- Virus-mediated transduction
- Gene editing tools e.g. CRISPR-Cas
- Chemogenetics (DREADDs)
- Optogenetics
- Copper-free Click Chemistry
Transduction of SCs with exogenous genes can be used to…
- drive expression of proteins not normally expressed in SCs
- treat haematological cancers using CARs
- control cell signalling pathways using optogenetic actuators
- increase expression of proteins normally expressed in SCs
- express WT proteins as a mechanism to functionally compensate for genetic mutations
What is the safest viral vector to use to facilitate stable long-term expression of a given exogenous gene, and why?
Lentivirus because it preferentially integrates into transcriptional unit - less likely to disrupt TSGs & protooncogenes
What is Kymriah?
An immunocellular therapy containing tisagenleleucel, autologous T cells genetically modified ex vivo using a lentiviral vector encoding an anti-CD19 CAR (enhances patient’s T cell response against tumour antigens)
Kymriah indications
- B cell acute lymphoblastic leukaemia in patients up to age 25 whose cancer did not respond to previous treatment, and has come back at least twice
- Diffuse large B cell lymphoma in adults whose cancer has come back or did not respond after 2 or more previous treatments
What is optogenetics?
Use of light-responsive proteins to activate cell signalling pathways when exposed to specific wavelengths of light