Moreover, it was more specific than the launched S1P1 agonist FTY720 on S1P3, which receptor maybe correlated with the risk of bradycardia in patients (Forrest et al., 2004; Sanna et al., 2004) and has better pharmacokinetic properties, such as a shorter half-life, which could make the lymphocytes recover soon after withdrawal once the patients had infection. Here, S1PR1 is linked to infection.