2. What is Animal Cell Technology ?
• Discipline of cell biology- aims to understand structures,
functions and behaviors of differentiated animal cells.
• Also to ascertain their abilities to be used in industrial
and medical purposes.
• Goal is the accomplishment
Clonal expansion of differentiated cells with useful ability,
Optimization of their culture conditions,
Modulation of their ability to produce medically and
pharmaceutically important proteins
The application of animal cells to gene therapy and
artificial organs.
3. History
• Ross Harrison (1907)- frog embryo nerve fiber outgrowth
in vitro.
• Carrel(1912)- explants of chick connective tissue, heart
muscle contractile for 2-3 months.
• Rous & Jones(1916)- trypsinization and subculture of
explants.
• Keilova(1948)- use of antibiotics in tissue culture.
• Gey et al. (1952)- First Human cell line HeLa
established.
• Eagle(1955)- development of defined media.
4. • Kleinsmith & Pierce (1964)- Pluripotency of embryonal
stem cells.
• Wiktor (1964)- Rabies, Rubella vaccines in WI-38 human
lung fibroblasts.
• Raham & Van der Eb(1973)- DNA transfer- calcium
phosphate.
• Kohler & Milstein (1975)- Hydridomas-monoclonal
antibodies.
• Ham & McKeehan (1978) -Serum free media.
• Freshney(2004)- Exploitation of tissue engineering.
8. PRIMARY CELL CULTURE
• Cells taken directly from a tissue to a dish
• Can be passaged after this with a limited number of
times. After the limit, the cell will die.
TYPES OF PRIMARY CELL CULTURE
• Mouse embryos
• Chick embryos
• Human biopsy materials
• Transplantable animal tumour
• Chick embryo organ rudiments (brain, heart, lungs, liver,
gizzard, kidney, spinal cord, skin, muscle)
10. • Mouse, mammals,
• Embryo
• Embryonated Eggs
• (best: for TC : embryo, young)
• because stage of differentiation)
cell culturing
organ
explant
Finely cut
Finely cut
tissue or explant
Enzymic digestion
Grow in media
-monolayer
-suspension cells
11. Enzymatic disaggregation
• Warm trypsin, 37˚C for 30 mins, cell damaged if too long
exposure.
• Cold preexposure, soak at 4C overnight and 37C for less 30
mins. Advantage: higher yield of viable cells, preserve
more cell types
• Other enzyme
-collagenase benefit for connective tissues and muscle
(fibrous tissue)
- pronase, dipase, DNase, hyaluronidase
Mechanical disaggregation (prevent proteolytic damage)
• Scrapping or spillage
• Sieving
• Syringes
• Trituration by pipette
13. CELL STRAIN
• If a subpopulation of a cell line is positively
selected from the culture by cloning or
some other method, this cell line becomes
a cell strain.
• Acquires additional genetic changes
14. CELL LINE
CELL LINE
FINITE IMMORTAL
• After the first subculture, the primary culture
becomes known as a cell line or subclone.
15. • After the first subculture, primary culture may be called
secondary cultures, and thereafter, if continued passage
is possible, a cell line.
• An established or immortalised cell line has acquired the
ability to proliferate indefinitely either through random
mutation or deliberate modification, such as artificial
expression of the telomerase gene.
18. MEASURING PARAMETERS OF
GROWTH
increasing the number of cells
increasing the size of the cells
increasing the amount of intercellular substance.
• Cell counting
Hemocytometer
Electronic Particle Counter
• Cell viability assay
• Measurement of
DNA amount
RNA amount
Protein amount
22. Subculturing
• Subculturing or "splitting cells," is required to
periodically provide fresh nutrients and growing
space for continuously growing cell lines.
• The frequency of subculture and the split ratio,
or density of cells plated depend on the
characteristics of each cell line being carried.
• Subculturing -
Adherent Cells
Suspension culture.
26. IMMORTAL CELL LINES?
• Transformed cell lines divide more rapidly and do not
require attachment to surface for growth, the loose
contact inhibition(tumors), It occurs spontaneously or
through interaction with viruses, oncogenes, radiation, or
drugs/chemicals.
• Characteristics
Infinite life span
High growth potential
Low growth factor dependence
Suspension growth
Aneuploid
27. HOW DO THEY BECOME IMMORTAL?
• Mutagens
• Viruses
• Oncogenes
• Spontaneous
28. ROLE AND USES OF CELL LINE
Immortalized cell lines are widely used as a simple
model for more complex biological systems.
for example:
• The biochemistry and cell biology of mammalian
(including human) cells.
• Immortalized cell lines can also be cloned giving
rise to a colonal population(genetically identical
cells).
• The testing toxicity of compounds or drugs to
production of eukaryotic proteins.
Editor's Notes
equation for cells in their exponential phase
for animal cell the doubling time is 17-35 hrs
DNA content G1 phase of diploid cell 6 pg/ml
protein content 100-500pg/ml