Regeneration of cartilage from autologous stem cells employing a loading system of physiological stress

物理应力的加载被认为对软骨组织很重要，因为体内软骨细胞会受到周期性的物理应力加载。为利用物理应力载荷进行软骨组织再生，研制了一种新型的细胞培养装置，可通过活塞头的垂直运动加载具有任意幅度(5~40 mm)、速度(0~100spm)、周期(0~1 Hz)、位移(0~2,000μm)、定时(1min~99h)的软骨细胞。幅度、速度和定时被维持在一个恒定值。将动应力周期调整为0.33赫兹，即步行周期。动态应激引起的葡萄糖消耗率是静态应激的两倍。但应激不影响细胞密度，降低aggrecan mRNA的表达，降低0.33~0.01 Hz的动态应力周期，缩短动、静态应力加载时间，不能提高细胞密度和aggrecan mRNA的表达。

Loading of physical stress is considered to be important for cartilage tissue, because chondrocyte cells in cartilage in vivo receive cyclic loading of physical stress. The novel cultivation apparatus which can load cells with physical stress having optional amplitude (5-40mm), velocity (0-100spm), cycle (0-1Hz), displacement (0-2,000μm), timing (1min-99h) through vertical move of a piston head, was developed in this study, aiming the utilization of physical stress loading for regeneration of cartilage tissue.Physical stress with displacement of 0.5mm was loaded dynamically or statically to three-dimensional culture of chondrocyte cells embedded into collagen gel which depth was 2mm. Amplitude, velocity, and timing were maintained to a constant values. The cycle of dynamic stress was adjusted to 0.33Hz, which was the cycle of walking. The dynamic stress resulted in the twice level of glucose consumption rate compared with the rate with static stress. However, the stress did not affect cell density and decrease the expression of aggrecan mRNA.Lowering the cycle of dynamic stress from 0.33 to 0.01Hz and decrease of loading time of dynamic and static stress could not improve cell density and the mRNA expression.