The lentivirus constructs used in this study. (a) LNT-Ii-CII, (b) LNT-Ii-CLIP, and (c) LNT-GFP. LNT (lentivirus), Ii (invariant chain), CII (collagen type II amino acids 259–270), CLIP (class II–associated invariant chain peptide). WPRE, woodchuck post-transcriptional regulatory element; cPPT, central polypurine tract; LTR, long terminal repeat.