Speaker
Lene Oddershede
(Niels Bohr Institute)
Description
Cells making up biological tissue are connected and their
motility highly correlated. The focus of this talk is on a
physical description of the complex dynamics of and within
cells comprising different tissue types. Endothelial cells
line the blood vessels. In healthy vessels with a laminar
blood flow, the endothelial cell division rate is low, only
sufficient to replace apoptotic cells. The division rate
significantly increases during embryonic development and
under halted or turbulent flow. Under non-flow conditions,
mimicking the condition around a blood clot, we show that a
cell division in endothelial tissue causes the emergence of
long-range well-ordered vortex patterns, in spite of the
system’s low Reynolds number [1]. Our experimental results
are reproduced by a hydrodynamic continuum model simulating
division as a local pressure increase. We also
experimentally mimic the conditions of a closing wound and
investigate how endothelial cells migrate into empty space,
and how this migration depends on flow conditions. Another
system studied is cancerous tissue, here, we correlate the
aggressiveness of cancer cells to their dynamics, with the
goal of achieving a deeper understanding of how dynamics is
related to cancer invasiveness. The last part of the talk
focuses on the dynamics of organelles inside living stem
cells, and how these tracers can be used as a mean to
characterize the mechanical properties of stem cells; we
found that the mechanical properties of embryonic stem cells
is highly correlated to their differentiation and that the
presence of actin might serve as a check-point for
differentiation control.
[1] Rossen, Tarp, Mathiesen, Jensen, Oddershede, Nature
Communications vol 5 p. 5720 (2014)
