Masters Thesis – AG De Laporte

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DWI Leibniz Institute for Interactive Materials

Position: Masters Thesis – AG De Laporte

Protein design and production to prepare biofunctional hydrogel systems

Hydrogels are soft, water-rich, polymeric networks, formed from a biocompatible precursor, and can take
up water to a volume fraction of more than 90%, depending on their degree of crosslinking and their
particular chemical composition. Their physical, mechanical, chemical, and biological properties can be
modified on a molecular level, which makes them ideal candidates to mimic the extracellular matrix (ECM)
and support and direct cell growth and functionality. Synthetic hydrogels can therefore be rendered
bioactive by modifying them with functional proteins. As ECM proteins are large, one can assemble and
produce specific ECM fragments, which are 10 times smaller than the entire ECM molecule, and investigate
and engineer their biological functionality. In addition, tailored peptide binding domains can be added to
the fragments to couple them covalently to a 3D hydrogel. The advantage of shorter fragments is that we
can add a higher concentration of the functional domains into the hydrogel.

In this project, we collaborate with the group of Angelika Lampert at the Uniklinik, which studies pain
signals in nerve cells. For this, they start from skin cells, which they use to produce induced pluripotent
stem cells (iPSCs) with the ability to be differentiated into peripheral sensory neurons. However, this
protocol shows large variability, especially concerning the expression of specific ion channels, which are
necessary to study the pain relevant signals. Therefore, our goal is to design a 3D hydrogel to i) enhance the
efficiency of stem cell differentiation into neurons, ii) create neurons with a higher number of these ion
channels in their membrane, and iii) foster the natural 3D growth of peripheral nerve cells into ganglionlike structures.
To do this, we will test the interaction of these channel proteins with different full length ECM proteins and
specifically produced ECM fragments, using custom-designed ELISAs. The ECM fragments will be
engineered and produced using e-coli bacteria. Selected fragments will then be coupled to the hydrogel
and tested with dissociated nerve cells from chick dorsal root ganglion. In collaboration with the Lampert
group, the gels will be tested with the stem cells and neurons to test their ability to increase the density of
these ion channels in the cell membrane.

Expertise: Biotechnologist, Biochemist, Chemist, Chemical Engineer, Biomedical Engineer.
The researcher should be interested in protein engineering and production and hydrogel systems to be
applied at the interface with cells.

Relevant literature:

- De Laporte L et al. Tenascin C promiscuously binds growth factors via its fifth fibronectin type III-like
domain. PLoS One, 2013 Apr; 8(4):e62076.
- De Laporte L et al. Engineering the regenerative microenvironment with biomaterials. Advanced
Healthcare Materials, 2013 Jan; 2(1):57-71.

Contact Info: Dr. Laura De Laporte delaporte@dwi.rwth-aachen.de

Please send your CV and transcripts in one PDF file.