Figure 1.

Normal maturation of MHC class II in Cat B knock-out mice. Cat B+ (A) or Cat B− (B) splenocytes were metabolically labeled for 30 min and chased for the times indicated in the absence or presence of leupeptin (1 mM) or LHVS (3 nM). MHC class II molecules were immunoprecipitated with mAb N22 and run in 12.5% reducing SDS/PAGE without (NB) or after (B) boiling. The position of the class II α and β chains, Ii, the p41 form of Ii, SDS-stable (peptide-bound) αβ complexes, the leupeptin-induced polypeptide LIP10, and the I-A^b-LIP10 SDS-stable complex (21, 47, 48), are indicated