ELISPOT analysis of the recognition of NY-ESO-1 p94-102 peptide by CD8+ T cell clone NW1539-CTL-1/15. NW1539-CTL-1/15 T cells (1000 cells/well) were incubated with irradiated, unpulsed (-) or NY-ESO-1 p94-102 peptide-pulsed (+) T2 or T2.A3 cells (5 x 10⁴ cells/well). Peptide-pulsed T2 and T2.A3 cells were recognized equally well, suggesting that HLA-B51 is the restriction element for T cell recognition.