In Vitro Toxicology

Question 1

How does In vitro differ from in vivo? (hint: name)

Answer 1

Studies are performed with the cells outside of the normal biological context (eg petri dish)

Question 2

What is the ECVAM?

Answer 2

European Centre for the Validation of Alternative Methods

Question 3

What is the ICCVAM?

Answer 3

Interagency Coordinating Committee on the Validation of Alternative Methods

Question 4

When did Hall propose his principles of ethical animal experimentation?

Answer 4

1831

Question 5

What were Hall’s 5 principles?

Answer 5

• 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

Question 6

When was the Health research extension act signed?

Answer 6

1985

Creation of the Institutional animal Care and Use committee (IACUC)

Question 7

What are the 3 R’s of toxicology? Who put them forth? and when?

Answer 7

Refinement, Reduction, and Replacement.

Russel and Burch, 1959

Question 8

Explain the 3 R’s of toxicology

Answer 8

Refine techniques to lessen pain

Reduce number of animals necessary

Replace animals with other models

Question 9

Describe the Guinea pig Maximization test, and its new version (Mouse local lymph node assay)

Answer 9

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

Question 10

List three advantages of LLNA over GPMT

Answer 10

Shorter duration
Fewer animals
Doesn’t need an adjuvant

Question 11

What are the different types of Transgenic mice?

Answer 11

Gene knockdown/specific mutations

Knock in (human gene/reporter)

Question 12

What are the pros (2) and cons (1) of transgenic mice?

Answer 12

Specific target yields decrease in number of animals
Decreases necessity for companion species

• most transgenics require additional care

Question 13

What is the main use in transgenic animals?

Answer 13

Carcinogenicity testing (tumor suppressants knocked out)

Question 14

Four examples of non-invasive monitoring?

Answer 14

Magnetic Resonance Imaging
Ultrasound Imaging
Computer-assisted Tomography
Positron Emission Tomogaphy`

Question 15

What causes contrast in CT scanning?

Answer 15

Differences in tissue absorption

Question 16

What is the typical positron-emitting molecule used in PET scans?

Answer 16

Fluorine-18

Question 17

Describe the steps in Muine Limb Bud culturing

Answer 17

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

Question 18

When would a researcher use an animal in a study?

Answer 18

If all alternatives have failed

• non-animal models (in vitro)
• Less sentient species (invertebrates)
• Computer modelling

Question 19

Name 2 examples of in vitro experiments

Answer 19

• In vitro skin irritancy test

- stem cells

Question 20

What are advantages of in vitro skin irritancy test? 3 things

Answer 20

Reproducible
Distinguishes corrosive/non corrosive (ECVAM approved)
Accepted by European Commission

Question 21

2 benefits of stem cell research

Answer 21

Study embryonic and developmental toxicity

Access to all cell types otherwise difficult to obtain

Question 22

When was toxicity testing approved by the ECVAM?

Answer 22

2008

Question 23

True/False? In vitro toxicology is mainstream.

Answer 23

True, all nobel prize winners for the past 20 years used IVT

Question 24

What is the endpoint used for in vitro tests? what are its 4 subtypes?

Answer 24

General cytotoxicity (necrosis)

• Breakdown of cellular permeability barrier
• Reduced MT function
• Changes in cell morphology
• Changes in cell replication

Question 25

Define a toxicity pathway

Answer 25

A cellular response that, when sufficiently perturbed, is expected to result in an adverse health effect

Question 26

What is tox21?

Answer 26

Toxicology in the 21st century (that’s it)

Question 27

Give an example of tox21

Answer 27

High throughput screening

Question 28

What is EVATAR?

Answer 28

Female menstrual cycle on a dish