FIG. 4.

TELEISSI shows a K^k-binding affinity comparable to that of a well-characterized K^k-restricted peptide. T2-K^k cells were incubated for 20 h in AIM-V medium at 29°C and then loaded with the indicated concentrations of peptide TELEISSI, the K^k-restricted influenza virus HA peptide FEANGNLI, the H-2D^b-restricted peptide KAVYNFATM derived from the LCMV glycoprotein (32), or no peptide for a further 16 h in AIM-V medium at 29°C. MHC class I cell surface expression was then measured by using monoclonal antibody 36-7-5 (BD PharMingen), which is directed against K^k. Relative peptide affinity is expressed as a fluorescence index (mean fluorescence with peptide/mean fluorescence without peptide). The results shown represent the mean values of three independent experiments.