In Vitro Toxicology Flashcards
How does In vitro differ from in vivo? (hint: name)
Studies are performed with the cells outside of the normal biological context (eg petri dish)
What is the ECVAM?
European Centre for the Validation of Alternative Methods
What is the ICCVAM?
Interagency Coordinating Committee on the Validation of Alternative Methods
When did Hall propose his principles of ethical animal experimentation?
1831
What were Hall’s 5 principles?
- An experiment should never be done if the necessary information can be obtained by observatino
- No experiment should be done without a clearly defined and obtainable objective
- Scientists should be well informed to prevent duplication of previously done work
- Experiments should be done with least infliction of suffering and use of “least sentient animals”
- Every experiment should be done under conditions that provide the clearest possible results
When was the Health research extension act signed?
1985
Creation of the Institutional animal Care and Use committee (IACUC)
What are the 3 R’s of toxicology? Who put them forth? and when?
Refinement, Reduction, and Replacement.
Russel and Burch, 1959
Explain the 3 R’s of toxicology
Refine techniques to lessen pain
Reduce number of animals necessary
Replace animals with other models
Describe the Guinea pig Maximization test, and its new version (Mouse local lymph node assay)
GPMT: Inject guinea pig with substance + adjuvant and measure response
LLNA: Apply sensitizers to mice, add radiolabelled thymidine, remove enhanced lymph nodes, suspend cells, test on those suspensions
List three advantages of LLNA over GPMT
Shorter duration
Fewer animals
Doesn’t need an adjuvant
What are the different types of Transgenic mice?
Gene knockdown/specific mutations
Knock in (human gene/reporter)
What are the pros (2) and cons (1) of transgenic mice?
Specific target yields decrease in number of animals
Decreases necessity for companion species
- most transgenics require additional care
What is the main use in transgenic animals?
Carcinogenicity testing (tumor suppressants knocked out)
Four examples of non-invasive monitoring?
Magnetic Resonance Imaging
Ultrasound Imaging
Computer-assisted Tomography
Positron Emission Tomogaphy`
What causes contrast in CT scanning?
Differences in tissue absorption
What is the typical positron-emitting molecule used in PET scans?
Fluorine-18
Describe the steps in Muine Limb Bud culturing
Get a mouse pregnant, Wait for the embryos to reach 12 days of age, chop their fore limbs off, culture limb buds with substance for 3 days, then 3 more days without substance, fix, stain, score differentiation
When would a researcher use an animal in a study?
If all alternatives have failed
- non-animal models (in vitro)
- Less sentient species (invertebrates)
- Computer modelling
Name 2 examples of in vitro experiments
- In vitro skin irritancy test
- stem cells
What are advantages of in vitro skin irritancy test? 3 things
Reproducible
Distinguishes corrosive/non corrosive (ECVAM approved)
Accepted by European Commission
2 benefits of stem cell research
Study embryonic and developmental toxicity
Access to all cell types otherwise difficult to obtain
When was toxicity testing approved by the ECVAM?
2008
True/False? In vitro toxicology is mainstream.
True, all nobel prize winners for the past 20 years used IVT
What is the endpoint used for in vitro tests? what are its 4 subtypes?
General cytotoxicity (necrosis)
- Breakdown of cellular permeability barrier
- Reduced MT function
- Changes in cell morphology
- Changes in cell replication
