Lecture 21 - Biopreservation Flashcards
1
Q
Why is biopreservation important
A
- seperates donor and recipient in space and time
- ex vivo preservation of cells
2
Q
Methods of biopreservation
A
- hypothermic storage
- cryopreservation
- vitrification
- lyophilization
3
Q
What is hypothermic storage
A
- temperature below physiologic temperature but not freezing
4
Q
What can be hypothermically stored
A
- blood cells
- stem cells
- corneas
- islets
- skin
- bone
- heart valves
- kidney
- liver
- pancreas
-heart - lungs
5
Q
What is cryopreservation
A
- long-term frozen preservation of ex-vivo function
6
Q
How are solutions cryopreserved
A
- liquid turns to ice
- the size of ice crystals depends on the cooling rate
7
Q
What is cell damage in cryopreservation associated wit h
A
concentrated solutions (causes membrane damage)
8
Q
What are cryoprotectants
A
- compound added to minimize the damaging effects of cryopreservation
9
Q
What are permeating cryoprotectants
A
- cross the cell membrane
- DMSO
- glycerol
- PG
10
Q
What are non-permeating cryoprotectants
A
- don’t cross cell membrane
- dehydrate cell by increasing extracellular osmolality
- decreased the probability of intracellular ice formation
- HES
- sucrose
- dextran
11
Q
What are disadvantages of CPA
A
- high concentrations can have toxic effects
- temperature dependent of cellular osmotic responses
- addition and removal
- cell specificity
12
Q
What is vitrification
A
- the solidification of a liquid by adjusting the composition and cooling rate such that ice formation is avoided
- progressive increase in viscosity during cooling and prevention of ice nucleation and growth
