Cell culture method using bone marrow-like structure, and porous polyimide film for healing bone injury site

A method of healing a bone injury site,

• including applying a porous polyimide film to an affected area of bone injury of a patient in need of healing the bone injury site,
• wherein the porous polyimide film has a three-layer structure consisting of an A-surface layer having a plurality of pores, a B-surface layer having a plurality of pores, and a macro-void layer sandwiched between the two surface layers,
• a mean pore size in the A-surface layer is smaller than a mean pore size in the B-surface layer, and
• the macro-void layer has a partition bonded to the A-surface layer and the B-surface layer, and a plurality of macro-voids surrounded by the partition, the A-surface layer, and the B-surface layer,
• wherein the bone injury is a fracture or bone loss,
• wherein cells have not been supported on the porous polyimide film, or mammal-derived bone marrow cells have been supported on the porous polyimide film beforehand;
• and
• wherein the A-surface layer of the porous polyimide film is applied to the affected area of bone injury of the patient.