Antagonistic activity of selected peptides on HA-1–specific CTL clones.
(A-C) Peptides were incubated with 51Cr labeled, HA-1 expressing EBV-BLCL at 37°C with the indicated peptide concentrations 30 minutes before the addition of CTL clones 3HA15 (A) 5W38 (B) and clone 15 (C). Percentage inhibition of lysis by antagonist peptides was calculated as described in “Materials and methods.” Average percentage inhibition of at least 3 independent experiments is shown with the SEM. Mean percentages lysis of HA-1+ EBV-BLCL in the absence of antagonistic peptides were 66% for 3HA15, 59% for 5W38, and 45% for clone 15. For the CTL clone 3HA15, the antagonistic effects of 3G and 3S were also determined in response to HA-1− target cells pulsed with 0.1 μg/mL HA-1 peptide (3G*, 3S*). (D) Response of HA-1–specific CTL clones to serial dilutions of HA-1 peptide loaded on HA-1− EBV-BLCLs.
