A therapeutic composition comprising gelatin and a cross-linking agent, for use in biological regenerative methods, which composition can be administered to a target area of the body while ensuring that the suspended cells and/or the growth factors remain in the target area of the body and at the same time eliminating the need for the patient to maintain the treated body area immobilized for unreasonable periods, is disclosed. A method is also disclosed, wherein (i) the gelatin and the cross-linking agent are mixed with each other to form the cross-linking therapeutic composition which is then administered to the target area or (ii) the gelatin and the cross-linking agent are made available in separate form and are administered, simultaneously or one after the other, to the target area while forming the cross-linking therapeutic composition.