TY  - JOUR
A1  - Bhuvanesh, Thanga
A1  - Machatschek, Rainhard Gabriel
A1  - Lysyakova, Liudmila
A1  - Kratz, Karl
A1  - Schulz, Burkhard
A1  - Ma, Nan
A1  - Lendlein, Andreas
T1  - Collagen type-IV Langmuir and Langmuir-Schafer layers as model biointerfaces to direct stem cell adhesion
JF  - Biomedical materials :  materials for tissue engineering and regenerative medicine
N2  - In biomaterial development, the design of material surfaces that mimic the extra-cellular matrix (ECM) in order to achieve favorable cellular instruction is rather challenging. Collagen-type IV (Col-IV), the major scaffolding component of Basement Membranes (BM), a specialized ECM with multiple biological functions, has the propensity to form networks by self-assembly and supports adhesion of cells such as endothelial cells or stem cells. The preparation of biomimetic Col-IV network-like layers to direct cell responses is difficult. We hypothesize that the morphology of the layer, and especially the density of the available adhesion sites, regulates the cellular adhesion to the layer. The Langmuir monolayer technique allows for preparation of thin layers with precisely controlled packing density at the air-water (A-W) interface. Transferring these layers onto cell culture substrates using the Langmuir-Schafer (LS) technique should therefore provide a pathway for preparation of BM mimicking layers with controlled cell adherence properties. In situ characterization using ellipsometry and polarization modulation-infrared reflection absorption spectroscopy of Col-IV layer during compression at the A-W interface reveal that there is linear increase of surface molecule concentration with negligible orientational changes up to a surface pressure of 25 mN m(-1). Smooth and homogeneous Col-IV network-like layers are successfully transferred by LS method at 15 mN m(-1) onto poly(ethylene terephthalate) (PET), which is a common substrate for cell culture. In contrast, the organization of Col-IV on PET prepared by the traditionally employed solution deposition method results in rather inhomogeneous layers with the appearance of aggregates and multilayers. Progressive increase in the number of early adherent mesenchymal stem cells (MSCs) after 24 h by controlling the areal Col-IV density by LS transfer at 10, 15 and 20 mN m(-1) on PET is shown. The LS method offers the possibility to control protein characteristics on biomaterial surfaces such as molecular density and thereby, modulate cell responses.
KW  - collagen-IV
KW  - basement membrane
KW  - Langmuir-Schafer films
KW  - stem cell adhesion
KW  - protein
KW  - ellipsometry
Y1  - 2019
U6  - https://doi.org/10.1088/1748-605X/aaf464
SN  - 1748-6041
SN  - 1748-605X
VL  - 14
IS  - 2
PB  - Inst. of Physics Publ.
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Deng, Zijun
A1  - Zou, Jie
A1  - Wang, Weiwei
A1  - Nie, Yan
A1  - Tung, Wing-Tai
A1  - Ma, Nan
A1  - Lendlein, Andreas
T1  - Dedifferentiation of mature adipocytes with periodic exposure to cold
JF  - Clinical hemorheology and microcirculation : blood flow and vessels
N2  - Lipid-containing adipocytes can dedifferentiate into fibroblast-like cells under appropriate culture conditions, which are known as dedifferentiated fat (DFAT) cells. However, the relative low dedifferentiation efficiency with the established protocols limit their widespread applications. In this study, we found that adipocyte dedifferentiation could be promoted via periodic exposure to cold (10 degrees C) in vitro. The lipid droplets in mature adipocytes were reduced by culturing the cells in periodic cooling/heating cycles (10-37 degrees C) for one week. The periodic temperature change led to the down-regulation of the adipogenic genes (FABP4, Leptin) and up-regulation of the mitochondrial uncoupling related genes (UCP1, PGC-1 alpha, and PRDM16). In addition, the enhanced expression of the cell proliferation marker Ki67 was observed in the dedifferentiated fibroblast-like cells after periodic exposure to cold, as compared to the cells cultured in 37 degrees C. Our in vitro model provides a simple and effective approach to promote lipolysis and can be used to improve the dedifferentiation efficiency of adipocytes towards multipotent DFAT cells.
KW  - Adipocyte
KW  - dedifferentiation
KW  - cold
KW  - lipid
Y1  - 2019
U6  - https://doi.org/10.3233/CH-199005
SN  - 1386-0291
SN  - 1875-8622
VL  - 71
IS  - 4
SP  - 415
EP  - 424
PB  - IOS Press
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Hausmann, Christian
A1  - Zoschke, Christian
A1  - Wolff, Christopher
A1  - Darvin, Maxim E.
A1  - Sochorova, Michaela
A1  - Kovacik, Andrej
A1  - Wanjiku, Barbara
A1  - Schumacher, Fabian
A1  - Tigges, Julia
A1  - Kleuser, Burkhard
A1  - Lademann, Juergen
A1  - Fritsche, Ellen
A1  - Vavrova, Katerina
A1  - Ma, Nan
A1  - Schaefer-Korting, Monika
T1  - Fibroblast origin shapes tissue homeostasis, epidermal differentiation, and drug uptake
JF  - Scientific reports
N2  - Preclinical studies frequently lack predictive value for human conditions. Human cell-based disease models that reflect patient heterogeneity may reduce the high failure rates of preclinical research. Herein, we investigated the impact of primary cell age and body region on skin homeostasis, epidermal differentiation, and drug uptake. Fibroblasts derived from the breast skin of female 20- to 30-yearolds or 60- to 70-year-olds and fibroblasts from juvenile foreskin (<10 years old) were compared in cell monolayers and in reconstructed human skin (RHS). RHS containing aged fibroblasts differed from its juvenile and adult counterparts, especially in terms of the dermal extracellular matrix composition and interleukin-6 levels. The site from which the fibroblasts were derived appeared to alter fibroblast-keratinocyte crosstalk by affecting, among other things, the levels of granulocyte-macrophage colony-stimulating factor. Consequently, the epidermal expression of filaggrin and e-cadherin was increased in RHS containing breast skin fibroblasts, as were lipid levels in the stratum corneum. In conclusion, the region of the body from which fibroblasts are derived appears to affect the epidermal differentiation of RHS, while the age of the fibroblast donors determines the expression of proteins involved in wound healing. Emulating patient heterogeneity in preclinical studies might improve the treatment of age-related skin conditions.
Y1  - 2019
U6  - https://doi.org/10.1038/s41598-019-39770-6
SN  - 2045-2322
VL  - 9
PB  - Nature Publ. Group
CY  - London
ER  - 
TY  - JOUR
A1  - Nie, Yan
A1  - Wang, Weiwei
A1  - Xu, Xun
A1  - Zou, Jie
A1  - Bhuvanesh, Thanga
A1  - Schulz, Burkhard
A1  - Ma, Nan
A1  - Lendlein, Andreas
T1  - Enhancement of human induced pluripotent stem cells adhesion through multilayer laminin coating
JF  - Clinical hemorheology and microcirculation : blood flow and vessels
N2  - Bioengineered cell substrates are a highly promising tool to govern the differentiation of stem cells in vitro and to modulate the cellular behavior in vivo. While this technology works fine for adult stem cells, the cultivation of human induced pluripotent stem cells (hiPSCs) is challenging as these cells typically show poor attachment on the bioengineered substrates, which among other effects causes substantial cell death. Thus, very limited types of surfaces have been demonstrated suitable for hiPSC cultures. The multilayer coating approach that renders the surface with diverse chemical compositions, architectures, and functions can be used to improve the adhesion of hiPSCs on the bioengineered substrates. We hypothesized that a multilayer formation based on the attraction of molecules with opposite charges could functionalize the polystyrene (PS) substrates to improve the adhesion of hiPSCs. Polymeric substrates were stepwise coated, first with dopamine to form a polydopamine (PDA) layer, second with polylysine and last with Laminin-521. The multilayer formation resulted in the variation of hydrophilicity and chemical functionality of the surfaces. Hydrophilicity was detected using captive bubble method and the amount of primary and secondary amines on the surface was quantified by fluorescent staining. The PDA layer effectively immobilized the upper layers and thereby improved the attachment of hiPSCs. Cell adhesion was enhanced on the surfaces coated with multilayers, as compared to those without PDA and/or polylysine. Moreover, hiPSCs spread well over this multilayer laminin substrate. These cells maintained their proliferation capacity and differentiation potential. The multilayer coating strategy is a promising attempt for engineering polymer-based substrates for the cultivation of hiPSCs and of interest for expanding the application scope of hiPSCs.
KW  - Polymeric substrate
KW  - surface coating
KW  - induced pluripotent stem cells
KW  - cell adhesion
Y1  - 2019
U6  - https://doi.org/10.3233/CH-189318
SN  - 1386-0291
SN  - 1875-8622
VL  - 70
IS  - 4
SP  - 531
EP  - 542
PB  - IOS Press
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Wang, Weiwei
A1  - Xu, Xun
A1  - Li, Zhengdong
A1  - Kratz, Karl
A1  - Ma, Nan
A1  - Lendlein, Andreas
T1  - Modulating human mesenchymal stem cells using poly(n-butyl acrylate) networks in vitro with elasticity matching human arteries
JF  - Clinical hemorheology and microcirculation : blood flow and vessels
N2  - Non-swelling hydrophobic poly(n-butyl acrylate) network (cPnBA) is a candidate material for synthetic vascular grafts owing to its low toxicity and tailorable mechanical properties. Mesenchymal stem cells (MSCs) are an attractive cell type for accelerating endothelialization because of their superior anti-thrombosis and immune modulatory function. Further, they can differentiate into smooth muscle cells or endothelial-like cells and secret pro-angiogenic factors such as vascular endothelial growth factor (VEGF). MSCs are sensitive to the substrate mechanical properties, with the alteration of their major cellular behavior and functions as a response to substrate elasticity. Here, we cultured human adipose-derived mesenchymal stem cells (hADSCs) on cPnBAs with different mechanical properties (cPnBA250, Young’s modulus (E) = 250 kPa; cPnBA1100, E = 1100 kPa) matching the elasticity of native arteries, and investigated their cellular response to the materials including cell attachment, proliferation, viability, apoptosis, senescence and secretion. The cPnBA allowed high cell attachment and showed negligible cytotoxicity. F-actin assembly of hADSCs decreased on cPnBA films compared to classical tissue culture plate. The difference of cPnBA elasticity did not show dramatic effects on cell attachment, morphology, cytoskeleton assembly, apoptosis and senescence. Cells on cPnBA250, with lower proliferation rate, had significantly higher VEGF secretion activity. These results demonstrated that tuning polymer elasticity to regulate human stem cells might be a potential strategy for constructing stem cell-based artificial blood vessels.
KW  - Poly(n-butyl acrylate)
KW  - mechanical property
KW  - vascular graft
KW  - mesenchymal stem cells
KW  - VEGF
Y1  - 2019
U6  - https://doi.org/10.3233/CH-189418
SN  - 1386-0291
SN  - 1875-8622
VL  - 71
IS  - 2
SP  - 277
EP  - 289
PB  - IOS Press
CY  - Amsterdam
ER  -