models of disease Flashcards
in vivo
cells growing in their normal biological context - inside the body
ex vivo
from the body but now outside the body - any experimentation using recently excised tissue in conditions as close to physiological as normal
explant
tissue growing outside the body in culture - outside normal biological context
invitro
cells growing in culture outside the normal biological context
how are cells maintained and forced to grow in culture
essential nutrients, correct physio-chemical environment, grown in a substrate/scaffold, growth factors
describe primary cells
limited lifespan and postnatally don’t divide/proliferate indefinitely
describe immortalized cells
ability to proliferate indefinitely either through random or deliberate modification
what is proliferation driven by
growth factors
fetal bovine serum
what is Hayflick Limit
mean number of doubling times before division ceases
telomeres and division
research shows that telomeres associated with each cell’s DNA will get slightly shorter with each new cell division until they shorten to a critical legth
10% confluency
ideal for plating/seeding - room to grow
30% confluency
good for transfection - tolerant of losses and room to grow before harvesting
50% confluency
will need to split soon ie 70-80% coverage, may take 2hr-2days depending on rate ofo doubling
90% confluency
very few spaces - cells touching, good for barrier function tests and western blot to maximise protein harvest
contact may inhibit growth in some cell types - induce quiescence
what do apoptotic cells not removed invitro do
secrete cytokines and chemokines onto adjacent cells - killing cell around them
