DWI - Leibniz Institute for Interactive Materials
Pre-programming anisometric microgels to orthogonally study the effect of mechanical signals on epithelia in 3D tissue models
Project overview. (A) shows a comparison of spheroid outgrowth in PEG hydrogels (6.5% [w/w]) with different ratios of degradable crosslinkers. (B) PEG hydrogel stiffening and softening can be induced on demand with UV light. (C) Nerve growth and alignment depends on microgel stiffness in Anisogel. (D) The angle of orientation of the microgels inside an Anisogel can be preprogrammed by pre-aligning ellipsoidal maghemite nanoparticles, resulting in orthogonal alignment of microgels and cells. (E) presents RGD-functionalized ester-linked PEG microgels (8-arm, 20 kDa, 5% [w/v]) covered with immortalized CD10 kidney epithelial cells after 4 days of cultivation. (F) Degradation of ester-linked PEG microgels is observed after adding 20 mg/ml cellulase (8-arm, 20 kDa, 5% [w/v]; degradation time: 10 h).
Department of Dental Materials and Biomaterials Research (ZWBF), Uniklinik RWTH Aachen
Mechanobiological challenges related to hydrogel-based bioprinting technology for manufacturing novel 3D cell culture models
Project overview. (A) Collagen fibers align in response to defined dynamic stress application. (B) shows a bioreactor to investigate the effect of fluid shear stress on epithelial cells. (C) The acoustic bioprinting principle is used for realization of advanced 3D in vitro epithelial models. Single cells and cell clusters can be precisely printed in 3D and are subjected to much less shear stress during printing due to the nozzle-less technology developed in our lab.
Neuroelectronic Interfaces, RWTH Aachen University
Development of light-driven deformable and electroactive 3D scaffolds for electromechanical modulation of epidermal tissues
Project overview. The aim is to use light-driven deformable 3D pillars (a-b) and photo-electroactive 3D pillars (c-d) to regulate keratinocyte motility, differentiation, and proliferations. (a, a’) shows poly(disperse red 1)-based light-driven deformable 3D pillars that were fabricated by means of photolithography and electron beam lithography [(a) before and (a’) after light stimulation]. (b, b’) shows fluorescence microscopy of Lifeact-RFP transfected U2OS cells growing on light-driven pillars before (b) and after light stimulation (b’). Scale bar: 10 µm. (c, c’) Shows F-actin ring-like arrangements of neurons around P3HT micropillars indicating membrane wrapping. The cells were transfected with Lifeact-RFP. Scale bar: 5 μm. (d, d’) Depicts paxillin-rich adhesions on P3HT micropillars (zoomed-in inset; green puncta). Cells were stained with TRITC-phalloidin (actin, red) and anti-paxillin antibodies (green). Scale bars: 5 μm, inset: 2 μm.