Abstract: The present invention relates to a process for producing an implant for medical purposes, to the implant obtainable by the process, and to the bioreactor used for the production of the implant. The implants of the invention can be used as implantable prostheses having essentially the functional characteristics of the following tissues: ligaments and tendons, bone and chondrogenic tissues, e.g. intervertebral discs, and combinations of bone tissue with cartilage tissue, e.g. sections of joints having the cartilaginous surface of a joint surface hacked by bone tissue. According to the invention, a porous matrix material is incubated under cell culture conditions with cells while the matrix is exposed to positive pressure on one side and negative pressure on another side for effective colonization of the matrix.