Advances in Using Organoids Flashcards
1
Q
Organoids
A
- mini organs
- derived from multi/pluripotent stem cells pushed to differentiate towards different fates via signalling molecules, growth media and manufactured ECM components
- pattered, self-organising 3D structures of <1mm
2
Q
Organoid advantages
A
- reconstitute the functionality of cell types and tissue organisation
- mimic development and physiology
- easy to establish and maintain for long durations, cheaply
3
Q
Organid disadvantages
A
- difficult to control differentiation
- hard to recapitulate physiological complexity (not vascularised, lack immunity)
- vulnerable to hypoxic stress
4
Q
Structure
A
- Organoids intro
- Applications
- ZIKV + HSV1
- Snake venom
5
Q
organoid uses
A
- drug development and screening away from animal use
- fundamental genetic, molecular and physiological function
- clinic: precision medicine
6
Q
Healthy individuals organoid research
A
cell:cell interactions affecting development arising from external stimuli
7
Q
Patients organoid research
A
- biobanking for disease modelling
- precision medicine
8
Q
disease modelling in biobanking
A
- pathogen genomic analyses
- screening for disease-related genetic variants
- metabolomic analysis
9
Q
precision medicine
A
- cell therapy
- drug development
- GE
10
Q
Escs
A
- mixed germ layers
- recapitulate embryonic/foetal developmental stages
11
Q
AdSCs
A
- pre-committed
- can recapitulated ageing + the physiological complexity of the epigenetic clock
- better studied
12
Q
Escs vs AdScs
A
a tradeoff
13
Q
Zika and HSV
A
- vertical transmission affects foetal brain development
- account for majority of congenital microcephaly
- we need a mechanistic understanding to treat
14
Q
ZIKV and HSVI in organoids
A
- ZIKV impairs growth of early stage brain organoids
- HSV1: even earlier
15
Q
ZIKV + HSV1 mechanism
A
apoptosis to prevent viral spread
16
Q
ZIKV transcriptional response
A
- IFN-sensitive element genes ^
17
Q
IFN in brain organoids + ZIKV
A
- attenuate: susceptibility
- recover with IFN-beta treatment
- decreased infection, microcephaly
18
Q
IFN in brain organoids + HSV1
A
- attenuate: susceptibility
- recover with IFN-alpha2 treatment
- decreased apoptosis
19
Q
Snakes
A
- produce venom cocktails
- > 100,000 fatalities / year
- require de novo transciptomics due to unpublished reference genomes
- studying is dangerous, time-consuming, expensive, difficult and often unethical
20
Q
venom gland organoids
A
- epithelial: AdScs
- secretory granules
- functionally active toxins
21
Q
viperids
A
haemotoxic enzymes
22
Q
elapids
A
smaller, neurotoxic peptides
23
Q
What have we learned from snake venom gland organdies?
A
- myotubes are a major venom tiger
- induction: Ca2+ wave stimulation
- inhibition = paralysis
24
Q
Studying nasopharyngeal sarcoma in organoids (Lucky et al., 2024)
A
- xenografts from 2x patient sources
- organoids are 1.4x less sensitive to radiation under hypoxia
- “low-oxygen resistant”
- treatment: low-dose fractionated radiation therapy
25
Why are cancer organdoids superior to cell culture?
- maintain heterogeneous and complex tumour micro-environment (intercellular + EM communication)
- closely mimics native organ structure (replicate filtration, excretion, neural connections and contraction)
- technically mature
- easily sourced
- rapid modelling cycle
- chemo evaluation (advanced metastasis, R)
- customisable: precision
26
Limitations of cancer organoids
- adaptations to artificial environment over time
- lack of stromal components, immune cells and vasculature
- limited scalability and reproducibility (difficult for high throughput screening)
- labour-intensive and time consuming
- mice do not suffer these
27
What do we need to overcome the limitations of cancer organoids?
- standardised protocols
- automation techniques
- long-term and dynamic culture methods
28
The next steps for cancer organoids
incorporating immunity!
29
Norovirus organoids
- stem-cell derived, non-transformed HIE multilayer cultures
- explain high virus infectivity + explosive illness
- how to treat and prevent transmission
30
HIE
- human intestinal enteroid
- isolated from intestinal crypts
- multicellular, differentiated
- enterocytes, goblet cells, enteroendocrines, chromaffin cells, Paneth cells
- physiologically active
- agonist responsive
31
How are norovirus organoids superior to cell culture?
- HuNoVs lack a robust and reproducible in vitro cultivation technique
- impossible to understand replication, stability, antigenic complexity and evolution
- attempt to culture in transformed HIEs + primary human immune cells have been unsuccessful
32
How do HuNoV organoids compare to animal models?
- gnotobiotic pigs
- newborn calves
- healthy adult volunteers
