A system (20), comprising: a subcutaneously implantable casing (24) configured for implantation in the body of a subject； functional cells (32) within the housing； an oxygen source arranged outside the housing, to supply oxygen to functional cells； an oxygen supply interface (27) on an exterior surface of the housing, to receive oxygen from the oxygen source and to facilitate the passage of oxygen to the functional cells, while the housing is arranged within the subject's body, comprising the oxygen supply interface (27) a penetrable surface； a needle to transcutaneously penetrate a penetrable surface, the housing (24) being indirectly coupled to the oxygen source through the needle, and the needle facilitating the supply of oxygen to functional cells (32) from the oxygen source, by minus an oxygen supply port (172) that is remotely arranged with respect to the housing (24), such that a tube (170) is coupled at a first end to port (172) and at a second end to the housing (24), in which the oxygen supply port (172) has an upper surface comprising the penetrable surface, of the oxygen supply interface (27), which can be penetrated by the needle, and a tank ( 42) oxygen inside the housing, to store oxygen received from the oxygen source at a pressure of 1 atm or more, the oxygen tank being in fluid communication with the functional cells.Un sistema (20), que comprende: una carcasa (24) implantable subcutáneamente, configurada para su implantación en el cuerpo de un sujeto； células funcionales (32) dentro de la carcasa； una fuente de oxígeno dispuesta fuera de la carcasa, para suministrar oxígeno a las células funcionales； una interfaz (27) de abastecimiento de oxígeno en una superficie exterior de la carcasa, para recibir oxígeno desde la fuente de oxígeno y para facilitar el paso del oxígeno a las células funcionales, mientras la carcasa está dispuesta dentro del cuerpo del sujeto, comprendiendo la interfaz (27) de abastecimiento de oxígeno una superficie penetrable；
