Figure 4.

Biochemical characterization of K^bFL binding to radiolabeled class I molecules. RMA cells incubated with or without K^bFL were pulse-radiolabeled with [³⁵S]-methionine and immediately incubated at 0°C (P) or chased for 15 min at 37°C (C). Detergent-soluble material bound to anti-fluorescein antibodies was analyzed by SDS/PAGE. In the last two lanes on the Right, peptide-exposed, unlabeled cells were mixed with radiolabeled cells not exposed to peptides before detergent extraction. Molecules comigrating with K^b recovered with specific antibodies are shown by the headed arrow.