Establishing a Human Blood Monocyte and Dendritic Cell Atlas. Researchers isolated approximately 2,400 cells enriched from the healthy human blood HLA-DR+ lineage- compartment and subjected them to single-cell RNA sequencing. This strategy, together with follow-up profiling and functional and phenotypic characterization, led them to update the original cell classification to include six dendritic cells (DCs), four monocyte subtypes, and one conventional DC progenitor. From Villani AC et al. Single-cell RNA-seq reveals new types of human blood dendritic cells, monocytes, and progenitors. Science. 2017. doi:10.1126/science.aah4573. Reprinted with permission from AAAS.