Dendritic cells in B6 CD45.1→B6 β2M^−/− or B6 IA^bβ^−/− are mostly donor in origin. Spleens and LNs were collagenase-treated, and cells were stained with a cocktail of lineage antibodies, anti-CD11c and anti-CD45.1 or CD45.2 (“Analysis of dendritic cell engraftment”). Shown is CD45.1 (——) and CD45.2 (----) staining of lineage^low CD11c⁺ cells from representative mice (at least 3 mice were analyzed from each group in each experimental repetition).