Figure 1.

Pretreatment with S1P inhibits CD1d-mediated NKT cell activation. (A) S1P levels in healthy donor and MCL patient sera were measured using ELISA. (B) NKT cells (DN32.D3) and B cell lymphomas (C1R-CD1d) were pretreated with vehicle (DMSO) or S1P (1 μg/mL) for 1 h at 37 °C. DN32.D3 (5 × 10⁴) NKT cell hybridomas were incubated with C1R-CD1d cells (2.5 × 10⁵) in the presence of α-GalCer (100 ng/mL) for 20–24 h. ELISA was used to measure IL-2 production. Data was analyzed by a two-tailed t-test with Welch’s correction. * p < 0.05.