Four-color flow cytometry and cytospin preparations of sorted subsets from synovium-rich tissue 14 days after adoptive transfer. The MHC IIhi cells (a) were analysed for expression of CD4 and/or CD11b (b). The fourth fluorochrome was used to detect expression of either CD11c (c) or CD163 (d) by the CD11b+ subsets. (e) Giemsa-stained cytospin preparations of the sorted CD11b+CD4+ subpopulation consisted mainly of cells with dendritic cell (DC) (arrows) or monocyte-like (arrowhead) morphology with a few cells of typical macrophage morphology (inset). (f) Giemsa-stained cytospin preparations of the sorted CD11b+CD4- subpopulation consisted mainly of cells with DC (arrows) or monocyte-like (arrowhead and inset) morphology. The sorted CD11b-CD4+ (g) and CD11b-CD4- (h) cells had morphology consistent with that described for plasmacytoid DCs. Objective, × 60. MHC, major histocompatibility complex.