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Fabrication of biomimetic placental barrier structures within a microfluidic device utilizing two-photon polymerization

was investigated. The cultivation of HUVECs in co- structures.
culture media showed increased proliferation after 24 Another advantage of this model lies in the adapt-
and 48 hours, compared to the control. This justifies ability of the geometry. The in vitro model has to reflect
the conclusion that serum concentrations slightly above changes in surface area of the placenta, occurring during
[3]
those in EGM-2 seem to enhance cell proliferation but the course of pregnancy . The use of the 2PP technique
does not negatively influence cell viability [37] . First using CAD models allows precise structural adaptability
tests with the established placenta-on-a-chip model of the certain geometry depending on the investigated
have shown that cell attachment and the formation of stage of pregnancy. To this end, surface area can be
a confluent cell layer on the walls of GelMOD-AEMA increased or reduced by addition or removal of villous
constructs was feasible. Both cells types, HUVEC and loops, respectively.
BeWo B30, were successfully seeded and cultured on Conflicts of Interest
the membrane walls for 7 days. Our future studies will
include optimization of cell seeding conditions and There are no conflicts to declare.
investigation of active glucose transport through the
membrane. Acknowledgements
5. Conclusions The financial support by the FWO Flanders (FWO SB
PhD grant, J.V.H.), the Austrian Science Funds (FWF
In conclusion, 2PP is an enabling manufacturing Project No. I2444-N28, A.O.) as well as the European
technology for establishing a versatile biomimetic on- Union’s Horizon 2020 research and innovation program
chip barrier structure suitable for the cultivation of (grant agreement No. 685817) and European Research
two different cell populations. In this work, collagen Council (Starting Grant-307701, A.O.) is gratefully
derived biopolymers, which resemble the extracellular acknowledged. Furthermore, we thank the team of the
matrix were applied instead of inorganic polymers. material science and technology department as well as
The compatibility of the microfabricated device with our colleagues from the institute of applied synthetic
microfluidic pumps enables its maintenance under chemistry at the Technical University of Vienna, for their
constant flow and thus the simulation of in vivo body support and critical comments that greatly improved
fluid flow. Customized chip design and channel this work. The authors thank Dr. Tina Buerki-Thurnherr
orientation thereby guarantee the tight separation of (EMPA, Switzerland) for providing BeWo B30 cells.
the culture compartments, with the advantage that the
respective cell type stays in the intended compartment References
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10 International Journal of Bioprinting (2018)–Volume 4, Issue 2