Structure and functional evaluation of tendon-skeletal muscle constructs engineered in vitro
Structure and functional evaluation of tendon-skeletal muscle constructs engineered in vitro
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DOI：
10.1089/ten.2006.12.3149
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发表时间：
2006-11-01
影响因子：
--
通讯作者：
Arruda, Ellen M.
中科院分区：
文献类型：
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作者：
Larkin, Lisa M.;Calve, Sarah;Arruda, Ellen M.
在肌肉收缩期间，肌腱连接（MTJ）的完整性对于力从肌肉到肌腱的传递是重要的。我们评估了与工程化自组织肌腱结构（n=4）或成人（n = 4）或胎儿（n=5）大鼠尾肌腱段共培养的三维（3-D）骨骼肌结构的收缩和结构特征。我们假设肌腱和肌肉的共培养将产生具有可行的肌肉-肌腱界面的结构，该界面在力的产生期间保持完整。测量结构直径（μ m）和最大等长力（μ N），并确定比力（kPa）。测量力后，以恒定应变率加载结构直至失效，光学记录肌腱、肌肉和界面的表面应变，并用于确定结构的切线模量（被动刚度）。冷冻样品用于三色Masson染色和MTJ特异性蛋白桩蛋白的免疫荧光分析。在直径、最大力或比力方面，未观察到组间差异。磁隧道结是坚固的，并承受超过生理应变范围的拉伸载荷。大多数结构在肌肉区域失效。在MTJ，桩蛋白的表达和定位增加。总之，使用3种来源的肌腱组织，我们成功地设计了具有功能可行的MTJ的3-D肌肉肌腱结构，其特征在于类似于体内新生儿MTJ的结构特征和蛋白质表达模式。
During muscle contraction, the integrity of the myotendinous junction (MTJ) is important for the transmission of force from muscle to tendon. We evaluated the contractile and structural characteristics of 3-dimensional (3-D) skeletal muscle constructs co-cultured with engineered self-organized tendon constructs (n=4), or segments of adult (n=4) or fetal (n=5) rat- tail tendon. We hypothesized that the co-culture of tendon and muscle would produce constructs with viable muscle-tendon interfaces that remain intact during generation of force. Construct diameter (mu m) and maximum isometric force (mu N) were measured, and specific force (kPa) was determined. After measure of force, constructs were loaded at a constant strain rate until failure and surface strains were recorded optically across the tendon, the muscle and the interface and used to determine the tangent modulus ( passive stiffness) of the construct. Frozen samples were used for Trichrome Masson staining and immunofluorescent analysis of the MTJ-specific protein paxillin. No differences were observed between the groups with respect to diameter, maximum force, or specific force. The MTJ was robust and withstood tensile loading beyond the physiological strain range. The majority of the constructs failed in the muscle region. At the MTJ, there is an increase in the expression and localization of paxillin. In conclusion, using 3 sources of tendon tissue, we successfully engineered 3-D muscle-tendon constructs with functionally viable MTJ, characterized by structural features and protein expression patterns resembling neonatal MTJs in vivo.