## 3 Results  
In this study, a TLC was developed based on collagen type I hydrogel, ASC and spider silk scaffolds. Handmade spider silk scaffolds were seeded as mentioned with a combination of rat collagen type I hydrogel and ASC. Constructs were divided into 4 groups as seen in Table 1. All constructs were incubated 9 days prior to further incubation in either the bioreactor or cell culture to allow cell adhesion and proliferation. After 9 days, constructs of experimental groups A and B underwent mechanical stimulation using the bioreactor for 21 days to induce differentiation of ASC. Experimental groups C and D were unstressed and cultured for 21 days and therefore served as controls. Every experimental group consisted of 2 constructs per cycle and 3 cycles were performed, receiving 6 constructs per experimental group. After a total of 30 days of incubation, all constructs were processed for further examinations. Histological and immunohistochemical staining as well as live-dead assays were performed after 30 days. Successful Preparation of Tendon-Like Constructs with 4 \(\times\) 10\({}^{5}\) ASC and Collagen Type I Hydrogel  
Drag line silk of spiders of the species _Nephila edulis_ was harvested and collected on custom-made stainless steel frames. As described above, a custom-made casting chamber was used to form stable TLCs (Figure 1). Steel frames with or without spider silk were placed in the casting chamber and the lid was closed. The hydrogel composing of collagen I and ASC was added using a pipette. After 90 min of incubation, stable constructs were achieved that underwent further incubation prior to mechanical stimulation using the bioreactor. Prior to first stressing using the bioreactor, contraction properties of collagen gels with and without spider silk as well as the optimal number of cells required for experiments were determined by measuring contraction characteristics of constructs. Table 2 displays an overview of experimental groups with different numbers of ASC for the contraction assay. Every experimental group consisted of 3 constructs to achieve comparable results. A minimum length of 4.5 cm was required to ensure a stable fixation of constructs in the bioreactor for further experiments. After two days of incubation, steel frames were cut off following another 28 days of incubation. The medium was changed every two days. The measurement results of the contraction assay with respect to the length of TLC are displayed in Table 3. The results are shown as mean value with the corresponding standard deviation in cm. Figure 3 shows a graphical overview of the contraction assay with respect to the length shortening according to Table 2.  
As shown in Table 2 and Figure 3, the constructs with spider silk showed a more pronounced contraction with respect to length. In the averaged triplicate, constructs of experimental group E had shrunk to 38.2 \(\pm\) 13.3% of their initial length whereas constructs  
Figure 3: Graphical evaluation of the contraction assay with respect to the length shortening according to Table 2. Experimental group E: TLC with spider silk and 5.0 \(\times\) 10\({}^{5}\) ASC. Experimental group F: TLC without spider silk and with 5.0 \(\times\) 10\({}^{5}\) ASC. Experimental group G: TLC with spider silk and 5.0 \(\times\) 10\({}^{6}\) ASC. Experimental group H: Construct without spider silk and with 5.0 \(\times\) 10\({}^{6}\) ASC. All measurements were made as triplicate (\(n\) = 3) and are graphically shown as mean \(\pm\) standard deviation. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Experimental** & \multirow{2}{*}{**Day 0**} & \multirow{2}{*}{**Day 1**} & \multirow{2}{*}{**Day 2**} & \multirow{2}{*}{**Day 9**} & \multirow{2}{*}{**Day 16**} & \multirow{2}{*}{**Day 23**} & \multirow{2}{*}{**Day 30**} \\
**Group (\(n\) = 3)** & & & & & & \\ \hline E & 15.00 \(\pm\) 0.00 & 14.83 \(\  
of experimental group F had shrunk to 31.1 \(\pm\) 11.9% of their initial length after 30 days of incubation.