The binding of FTY720-P to the S1PR1 on lymphocytes leads first to activation and then subsequent S1PR1 downregulation (i.e., by the internalisation and degradation of S1PR1 on the lymphocytes), thus preventing aggressive infiltration of lymphocytes from the lymphoid tissue into the blood, bringing about a state of peripheral lymphopenia, and limiting the inflammatory response [115]. Here, S1PR1 is linked to lymphopenia.