Abstract: In the present invention, because no examples are known of binding of magnetic particle to mesenchymal cell or chondrocyte which might be used in regenerative medicine, whether or not a cell having the magnetic particle bound thereto is retained in local by external magnetism after administration and whether or not the cell can exhibit intrinsic activity is studied. According to the present invention, a magnetic cell comprising mesenchymal cell or cultured chondrocyte having magnetic particle bound to the surface thereof is provided, and when the cell is administered in vivo and an external magnetic field is applied, the cell can be retained for a long time at a disease site. Moreover, a drug delivery system can be constructed by causing the magnetic cells to contain a drug.

Abstract: To determine the transplant compatibility of an in vitro cultured tissue, a method measures the stiffness of the cultured tissue by using a stiffness measuring device, which stiffness measuring device includes a detecting unit and calculation means, the detecting unit includes a contact unit, a vibrator connected to the contact unit, and a vibration detecting unit for detecting the vibration of the vibrator, and the calculation means determines stiffness information by calculation based on the detected result from the vibration detecting element; and by bringing the contact unit into contact with the cultured tissue. With this method the transplant compatibility of the cultured tissue can be nondestructively and easily determined easily and the quality of the cultured tissue can be appropriately controlled.

Abstract: To determine the transplant compatibility of an in vitro cultured tissue, a method measures the stiffness of the cultured tissue by using a stiffness measuring device, which stiffness measuring device includes a detecting unit and calculation means, the detecting unit includes a contact unit, a vibrator connected to the contact unit, and a vibration detecting unit for detecting the vibration of the vibrator, and the calculation means determines stiffness information by calculation based on the detected result from the vibration detecting element; and by bringing the contact unit into contact with the cultured tissue. With this method the transplant compatibility of the cultured tissue can be nondestructively and easily determined easily and the quality of the cultured tissue can be appropriately controlled.