Extended data Figure 2.

(a) Three T cells lines containing CD1a-lysylPG tetramer+ T cells were staining with lysylPG-treated CD1b, CD1c, and CD1d tetramers co-stained with anti-CD4 and analyzed by flow cytometry. Plots are gated on live T cells. (b) Human CD1/β2m isoforms were expressed in Expi293F GnTI- cells and purified by nickel-affinity and size exclusion chromatography. CD1 proteins carrying endogenous lipids (CD1-endo) were incubated with lysylPG 16 hrs at 25°C in 0.1 M MES pH5.5, 150mM NaCl, 0.05% CHAPS. 1 µg of CD1-endo and CD1-lysylPG samples were loaded on a 3–9 gel (Cytiva), and displacement of endogenous lipid and/or shifts towards more electropositive values indicate efficient loading of lysylPG. (c) GM-CSF concentration in supernatant of CD1a-lysylPG tetramer+ T cell line (921a) after 24hrs of incubation with plate-bound CD1a and indicated concentrations of PC, PG and lysylPG. Indicated are mean ± SD of triplicate values. P values were based on paired two-tailed t-test. * p<0.05 ** p<0.01