According to the "Reflection paper on classification of advanced therapy medicinal therapy", published by the Committee for Advanced Therapies (CAT) of the European Medicine Agency on June 20th 2014 [EMA/CAT/600280/2010 Rev.1 lines 118-131] the Treg DLI SHOULD NOT BE CONSIDERED CELL THERAPY MEDICINAL PRODUCTS. Indeed somatic cell therapy medicinal product means a biological medicinal product which fulfils BOTH following two characteristics: (a) contains or consists of cells or tissues that have been subject to substantial manipulation so that biological characteristics, physiological functions or structural properties relevant for the intended clinical use have been altered, or of cells or tissues that are not intended to be used for the same essential function(s) in the recipient and the donor; (b) is presented as having properties for, or is used in or administered to human beings with a view to treating, preventing or diagnosing a disease through the pharmacological, immunological or metabolic action of its cells or tissues. For the purposes of point (a), the manipulations listed in Annex I to Regulation (EC) No 1394/2007, including cutting, grinding, shaping, centrifugation, soaking in antibiotic or antimicrobial solutions, sterilization, irradiation, cell separation, concentration or purification, filtering, lyophilization, freezing, cryopreservation, and vitrification, shall not be considered as substantial manipulations. The procedures listed above for the preparation of the purified T reg product DO NOT FULFILL the definition of substantial manipulation.