In an operating room 8, about 40 mL of the bone marrow fluid 10 of a patient is sampled and housed in a collection tube 11. Then, the collection tube 11 is conveyed into an isolator 2 in a sterile state. In the isolator 2, the bone marrow fluid 10 in the collection tube 11 is pipetted into test tubes 13, culture tubes 14, etc. To the bone marrow fluid 10 in the culture tubes 14, an erythrocyte sedimentation agent is added. After thus precipitating erythrocytes, the supernatant is collected. From the collected supernatant, a bone marrow cell-containing fraction for liver regeneration is concentrated. The obtained concentrate is pipetted into flasks 5 (culture containers). Then, the flasks 5 are conveyed into an incubator 4 to start cell incubation. From the isolator 1, test tubes 13 and 16 are taken out. The bone marrow fluid 10 in the test tubes 13 and 16 and the concentrate are subjected to a safety inspection, etc. Thus, the safety of the bone marrow fluid 10 sampled from the patient can be inspected immediately after starting the incubation.
