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bioRxiv · 10.1101/828947

Morphogenesis guided by 3D patterning of growth factors in biological matrices

Broguiere, N.·Luechtefeld, I.·Trachsel, L.·Mazunin, D.·Bode, J.·Lutolf, M.·Zenobi-Wong, M.
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Abstract

Three-dimensional (3D) control over the placement of bioactive cues is fundamental to understand cell guidance and develop engineered tissues. Two-photon patterning (2PP) provides such placement at micro- to millimeter scale, but non-specific interactions between proteins and functionalized extracellular matrices (ECMs) restrict its use. Here we report a 2PP system based on non-fouling hydrophilic photocages and Sortase A-based enzymatic coupling offering unprecedented orthogonality and signal-to-noise ratio in both inert hydrogels and complex mammalian matrices. Improved photocaged peptide synthesis, and protein functionalization protocols with broad applicability are introduced. Importantly, the method enables 2PP in a single step and in the presence of fragile biomolecules and cells. As a corollary, we demonstrate the guidance of axons through 3D-patterned nerve growth factor (NGF) within brain-mimetic ECMs. Our approach allows for the interrogation of the role of complex signaling molecules in 3D matrices, thus helping to better understand biological guidance in tissue development and regeneration.

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Broguiere, N., Luechtefeld, I., Trachsel, L., Mazunin, D., Bode, J., Lutolf, M., Zenobi-Wong, M.. 2019-11-07. Morphogenesis guided by 3D patterning of growth factors in biological matrices. https://doi.org/10.1101/828947

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