A GMM-specific T cell line in which the majority of cells are known to express the T cell receptor alpha (TCR-α) variable segment, TRAV1-2, was serially diluted with an α-GalCer-specific CD1d-restricted cell line, which does not express TRAV1-2. The cells were co-stained with GMM-CD1b tetramer and anti-TRAV1-2. (A) Representative staining from three dilutions (0.01%, 0.1%, and 1%) in which the fraction of CD3+ cells that stain with GMM-CD1b tetramer (top) or with TRAV1-2 (bottom) is shown. (B) Correlation between GMM-CD1b and TRAV1-2 staining. TRAV1-2 staining in the absence of GMM-specific T cells is likely reflective of low frequency TRAV1-2+ cells present in the α-GalCer T cell line. Data are representative of three independent experiments.