Lyso strongly stimulated two different sulfatide reactive hybridomas. XV19 cells (A) or 14S.15.5D cells (B, C) were stimulated with APC pre-incubated with native sulfatide isolated from pig brain (Native (1), see Materials and methods) or commercially available native sulfatide from bovine brain (Native (2), Matreya), lyso, all at 30 nmol/ mL, or vehicle control (DMSO (A), or medium, –, (B)). XV19 cells were stimulated using JawsII (5 × 103 cells/well), and 14S.15.5D with RAW-mCD1d cells (10 × 103 cells/well) as APC. Activation was measured in a CTLL-2 bioassay. Data are representative of at least three experiments performed (mean ± SD of triplicate cultures).