TY  - JOUR
A1  - Tylek, Tina
A1  - Blum, Carina
A1  - Hrynevich, Andrei
A1  - Schlegelmilch, Katrin
A1  - Schilling, Tatjana
A1  - Dalton, Paul D
A1  - Groll, Jürgen
T1  - Precisely defined fiber scaffolds with 40 μm porosity induce elongation driven M2-like polarization of human macrophages
JF  - Biofabrication
N2  - Macrophages are key players of the innate immune system that can roughly be divided into the pro-inflammatory M1 type and the anti-inflammatory, pro-healing M2 type. While a transient initial pro-inflammatory state is helpful, a prolonged inflammation deteriorates a proper healing and subsequent regeneration. One promising strategy to drive macrophage polarization by biomaterials is precise control over biomaterial geometry. For regenerative approaches, it is of particular interest to identify geometrical parameters that direct human macrophage polarization. For this purpose, we advanced melt electrowriting (MEW) towards the fabrication of fibrous scaffolds with box-shaped pores and precise inter-fiber spacing from 100 μm down to only 40 μm. These scaffolds facilitate primary human macrophage elongation accompanied by differentiation towards the M2 type, which was most pronounced for the smallest pore size of 40 μm. These new findings can be important in helping to design new biomaterials with an enhanced positive impact on tissue regeneration.
KW  - cell elongation
KW  - human macrophages
KW  - melt electrowriting (MEW)
KW  - macrophage polarization
KW  - 3D scaffolds
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-254012
VL  - 12
IS  - 2
ER  - 
TY  - JOUR
A1  - Hochleitner, Gernot
A1  - Jüngst, Tomasz
A1  - Brown, Toby D
A1  - Hahn, Kathrin
A1  - Moseke, Claus
A1  - Jakob, Franz
A1  - Dalton, Paul D
A1  - Groll, Jürgen
T1  - Additive manufacturing of scaffolds with sub-micron filaments via melt electrospinning writing
JF  - Biofabrication
N2  - The aim of this study was to explore the lower resolution limits of an electrohydrodynamic process combined with direct writing technology of polymer melts. Termed melt electrospinning writing, filaments are deposited layer-by-layer to produce discrete three-dimensional scaffolds for in vitro research. Through optimization of the parameters (flow rate, spinneret diameter, voltage, collector distance) for poly-ϵ-caprolactone, we could direct-write coherent scaffolds with ultrafine filaments, the smallest being 817 ± 165 nm. These low diameter filaments were deposited to form box-structures with a periodicity of 100.6 ± 5.1 μm and a height of 80 μm (50 stacked filaments; 100 overlap at intersections). We also observed oriented crystalline regions within such ultrafine filaments after annealing at 55 °C. The scaffolds were printed upon NCO-sP(EO-stat-PO)-coated glass slide surfaces and withstood frequent liquid exchanges with negligible scaffold detachment for at least 10 days in vitro.
KW  - additive manufacturing
KW  - 3D printing
KW  - biodegradable polymers
KW  - microstructures
KW  - nanostructures
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-254053
VL  - 7
IS  - 3
ER  -