The development of large tissue engineered bone remains a challenge in vitro, therefore the use of hybrid-implants might offer a bridge between tissue engineering and dense metal or ceramic implants. Especially the combination of the pseudoelastic implant material Nitinol (NiTi) with adipose derived stem cells (ASCs) opens new opportunities, as ASCs are able to differentiate osteogenically and therefore enhance osseointegration of implants. Due to limited knowledge about the effects of NiTi-structures manufactured by selective laser melting (SLM) on ASCs the study started with an evaluation of cytocompatibility followed by the investigation of the use of SLM-generated 3-dimensional NiTi-structures preseeded with ASCs as osteoimplant model. In this study we could demonstrate for the first time that osteogenic differentiation of ASCs can be induced by implant-mediated mechanical stimulation without support of osteogenic cell culture media. By use of an innovative implant design and synthesis via SLM-technique we achieved high rates of vital cells, proper osteogenic differentiation and mechanically loadable NiTi-scaffolds could be achieved.

Adipose-derived stem cells (AScs) can easily be obtained and expanded in vitro for use in autologous cell therapy. Via their production of cytokines and neurotrophic factors, transplanted AScs provide neuroprotection, neovascularization and induction of axonal sprouting. However, the influencing mechanism of undifferentiated AScs on nerve regeneration is currently only partially understood. In the present study, undifferentiated AScs and cutaneous primary afferent dorsal root ganglion (dRG) neurons were co-cultured in order to investigate their interaction. AScs were isolated from adult rat fat tissue. The presence of characteristic stem cell markers was determined by flow cytometry in three subsequent passages. Adipogenic, osteogenic, chondrogenic and glial differentiation was performed in order to evaluate their differentiation capacity. A direct co-culture system with dRG cells was established to determine the effect of undifferentiated pluripotent AScs on neurite elongation. Neurite outgrowth, length and number was examined in the co-culture and compared with single-culture cells and cells stimulated with nerve growth factor (NGF). In ASc cultures, NGF expression was assessed by ELISA. The present results demonstrated that the specific mesenchymal stem cell surface markers cd44, cd73 and cd90 were detected in all three subsequent passages of the isolated ASCs. In accordance, ASc differentiation into adipogenic, osteogenic, chondrogenic and Schwann cell phenotype was conducted successfully. Neurite outgrowth of dRG neurons was enhanced following co-culture with AScs, resulting in increased neurite length after 24 h of cultivation. Furthermore, neurite outgrowth of dRG neurons was directed towards the undifferentiated ASc and direct cell-to-cell contact was observed. In summary, the results of the present study revealed an interaction between the two cell types with guidance of neurite growth towards the undifferentiated ASC. These findings suggest that the use of undifferentiated ASc optimizing tissue-engineered constructs may be promising for peripheral nerve repair.

Due to fascinating mechanical and biological characteristics spider silk is of great interest in many research fields. Among the orb-weavers Nephila edulis is one of the species used as source for natural spider silk in laboratories. Under appropriate conditions, animals can be kept and bred easily. This manuscript gives information about the spiders' natural habitat, behavior, and breeding and compares them with the established methods and conditions within a research laboratory. Keeping conditions and methods of rearing are described in detail. Within a keeping facility with reliable supply of food, cannibalism rate is significantly reduced and spiders mate all year long. Cohabitants of the genus Steatoda are routinely found in laboratory keeping. While these small spiders do not pose a threat to Nephila edulis, cellar spiders (family Pholcidae) have to be extracted as they have been observed hunting for Nephila spiders.

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