Figure 4.

Effect of glutaraldehyde fixation on the sensitization of target cells by epitope peptides. (a) ⁵¹Cr-labelled, glutaraldehyde-fixed (closed symbols) or unfixed (open symbols) BALB/c.3T3 cells were incubated with 3 µm of peptide P18IIIB (circles) or I-10 (squares) for 2 hr at 37°. They were then washed three times and used as target cells. LINE-IIIB cells were used as effector cells. (b) ⁵¹Cr-labelled, glutaraldehyde-fixed BALB/c.3T3 cells were incubated with or without captopril for 30 min. Then 5 × 10³ captopril-treated (closed symbols) or untreated (open symbols) cells were incubated with 5 × 10⁴ LINE-IIIB cells in the presence of various amounts of peptide P18IIIB (circles) or I-10 (squares) in 96-well round-bottom microtitre plates during the CTL assay. Captopril (400 µm) was present throughout the assay.