Temperature dependent responses of live mammalian cells
Authors: Balaganesh Natarajan1, Kaho Long2, Shuting Zhang2, Chaitali Vyas3, Hairong Ma2
1 – Department of Biology, 2 – Department of Physics, 3 – School of Biomedical Engineering
Drexel University, Philadelphia, PA, USA Abstract
One of the most important forms of homeostasis
is temperature regulation. If the body temperature
goes outside of accepted range then the cells will start
to break down, and lose their function since they can’t
perform any of their chemical reactions. Cell injury can
be irreversible or reversible depending on how great of
exposure is. Greater amounts of exposure will cause
the cell’s membrane to breakdown, and result in their
deformity. The type of cells that were worked with
were Hela Cells and the line of these cells were called
ZSPD. The goal of the experiment is to establish the
temperature affect of the Hela Cells and observe how
they react to several different temperatures. The Hela
cells were observed under a light microscope using an
imaging camera. The temperature was controlled
using a heating apparatus stand, which can be fixed
onto the microscope. These cells can be observed
while heated using the heating controller.
Results
(1) Cell Viability
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Hela cells became less transparent due to the increase in
temperature. You can see this from Figure 4.
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Experimental Set-up
The way cells were differentiated between live
and dead was through the use of trypan blue. The dead
cells would be a dark blue color while the live cells
would be clear. The Hela cells were used to measure
the cell viability under various thermal stress conditions.
The various thermal stress conditions were modulated
by the heating apparatus controller which is connected
to the heating apparatus stand. The Hela cells were
heated for 11 minutes by the heating apparatus. After
waiting 11 minutes for the dish to heat up the cell
viability for each dish was immediately examined. By
looking at Figure 2 above you can see that cell viability
decreases with increasing temperature.
(2) Morphology
From Figure 1 you can see how the experiment
for heating and observing the cells was set up. The
cell dish was put on the heating apparatus stand, and
the heating apparatus controller was connected to the
heating apparatus stand to control the temperature of
the cell dish.
The cell’s membranes are composed of lipids
and proteins that can survive under certain conditions,
but when there’s a huge increase or decrease in
temperature, these highly organized structures that
gives each cell its particular shape will start to fall apart.
This can be seen from Figure 3.
Conclusion
From the experiments it was seen that as the temperature
increased the cell viability decreased. Also as the temperature
increased the transparency decreased and the cells
morphology became more deformed.
Outlook
The next step of our experiments is to use molecular
reporters to observe the stress induced responses in living
cells, and to investigate how changes in shape affect cell
functionality.