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The Cultivation of Human Embryonic Stem Cells on Various Matrixes and the
Cultivation of the Cell Culture Line H9 on Laminin 511
Summary
Human embryonic stem cells (hESC-s) proliferate and maintain pluripotency on
various matrixes and in various media. The best system for growing hESC-s for scientific
research is growing hESC-s on Matrigel and in mTeSR1/2 medium. Compared to other
systems, this system provides the highest growth rate as well as the highest percentage of
pluripotent hESC-s. In scientific research as well as for therapeutic applications, matrixes
based on alginate and chitosan, are very promising. However, defined medium, that could be
used with these matrixes, has not yet been found.
Human embryonic stem cells have also been grown in suspension. This systems
requires the addition of exogenous laminin 511 to the cell cultrure medium. However, it is
evident from scientific research, that hESC-s do not need laminin 511 as a matrix but seem to
need a signal to make them produce it themselves. This states the difference of biological
activity between the laminin, that is freely in the medium, and the laminin that is adhered on
glass or plastic. The cultivation of hESC-s in suspension resembles very well the natural
development of an embryo in the fallopian tube and in the uterus.
In this research we cultivated hESC-s on Lm511 that was adhered on glass. Colonies
of hESC-s asquire bizarre morphology already on the first day after the passage and compared
to the colonies on Matrigel the overall number of colonies as well as the percentage of
pluripotent cells declines. Our results are in agreement with Vuoristo et al (2008) and show
that hESC-s produce Lm511. However, differently from Vuoristo et al (2008) but in
agreement with Braam et al (2008) our results show, that hESC-s do not produce Lm111.
Our results also prove the presence of Lm111 in Matrigel.
The scientific research also show that in addition to signals regulated by laminin,
hESC-s need signals from growth factors, out of which most important are signals induced by
bFGF. It is yet to be determined whether the signal from laminin 511 is required for the
proliferation or for the maintenance of pluripotency.
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