Method for aggregating cell mass and device for aggregating cell mass

A method for aggregating cell masses, comprising:

• the step of attaching a first end and a second end of a tubular shaped base material that is an artificial blood vessel or a regeneration blood vessel, respectively, to a first mounting portion and a second mounting portion that are arranged on a central axis of the rotating body and are spaced apart from each other, to linearly extend the base material on the central axis from the first end to the second end without bending the base material and to connect the first mounting portion and the second mounting portion via the artificial base material;
• and
• a cell mass aggregating step of rotating at the rotation speed a rotating body containing a specific gravity adjustment solution and cell masses and aggregating the cell masses on an outer surface of the base material by centripetal force acting on the cell masses due to rotation of the rotating body and difference in specific gravity between the specific gravity adjustment solution and the cell masses, the specific gravity adjustment solution having biocompatibility, the cell masses having a lower specific gravity than the specific gravity adjustment solution, and the rotation speed being selected to cause cell aggregation by the centripetal force.