Abstract: The invention provides a method for modulating the surface characteristics of a device, which is at least temporarily in contact with, a body fluid and/or a body tissue, which is characterized in that the device is coated at least with a ligand that binds at least one of the body's own molecules, wherein the modulation effect is caused substantially by the body's own molecule. The invention thus relies on an auto-protection principle wherein the patient's own substances are used in order to modulate the surface characteristics. Furthermore devices are disclosed which are capable of presenting a modulated surface.