The reduced ubiquitination of S1P1 and degradation and the increased recycling of S1P1 with AKP-11 as compared to FTY720 or FTY720P following withdrawal of AKP-11 (Figs 7 & 8) could possibly be basis of milder and reversible lymphopenia effect observed with AKP-11. The gene discussed is S1PR1; the disease is lymphopenia.