Lectures 4-7 Flashcards
3 possible ways to grow/cultivate viruses
cell/tissue culture, inoculation in embryonated egg, lab animals
advantages of using primary cell culture
best culture system for isolation and propagation of viruses, heterogeneous cells, closest to live animal, used in producing viral vaccines
disadvantages of primary cell culture
difficult to obtain, short lifespan, susceptible to contamination, may not entirely act like parent tissue
characteristics of finite cell lines
limited life span, more homogeneous cells, mainly derived from embryos or from secondary cell cultures, slow growth rate, can be used for vaccine production
Characteristics of continuous cell lines
the most homogeneous (1 cell type), derived from cancer cells, least similar to live animal, rapid growth rate, prohibited to use for vaccine production
Cell culture medium
provides all necessary nutrients required for cell growth
serum in culture
vital source of adhesion factors, attachment and spreading factors, nutrients, hormones and growth factors. required for growth and maintenance of cells. fetal bovine serum most common
Phenol red
pH indicator to ensure culture is at proper temperature. turns orange/yellow if acidic pH, remains red at pH of 7. pH drops due to contamination or buildup of toxic metabolites
CO2 levels in culture
Changes in environmental pH may alter culture pH –> use exogenous CO2 when using a CO2-bicarbonate based buffer medium (CO2 incubator)
trypsin
protease used to detach cells to form subculture
Cytopathic effect (CPE)
damage/changes to host cells due to virus cell invasion
Routes of egg inoculation
Yolk sac, allantoic cavity, amniotic cavity, chorioallantoic membrane
Signs of virus growth (in egg inoculation)
death of embryo, paralysis, stunted growth, pocks on CAM
Virus titer
lowest concentration of a virus that can still infect cells.
Biological quantification tests
dependent on the virus completing a replication cycle. Includes: plaque assay, pock assay, endpoint titration
