Summary of selected established and proposed functional differences between human CD16- and CD16+ monocyte subsets. Genes expressed at a high level in one subset but not in the other are indicated. Gene labels are positioned according to the location of the protein in the cell - in the plasma membrane, the cytoplasm or the nucleus. Several studies have previously confirmed high levels of expression in human CD16+ monocytes of the genes for the chemokine receptor CX3CR1, the integrin alpha chain ITGAL and the adhesion molecule CD31 and strong expression in human CD16- monocytes of genes for the adhesion molecule CD62L, the high-affinity Fc receptor for IgG (CD64), and the chemokine receptors CCR1 and CCR2. The new studies add many candidates to the monocyte subsets markers list, a selection of which is represented in the figure. Previously confirmed markers are in bold. A list of differentially expressed genes found by both [6, 7] is given in Additional data file 1. Other abbreviations of markers: ALDH2, aldehyde dehydrogenase 2 family; C3AR1, complement component 3a receptor 1; CD26, dipeptidyl-peptidase 4; CD93, CD93 molecule; CD99, CD99 molecule; CSF1R, colony stimulating factor 1 receptor; CSF3R, colony stimulating factor 3 receptor; CTSC, cathepsin C; CD97, CD97 molecule; FPR1, formyl peptide receptor 1; HIF1A, hypoxia inducible factor 1, alpha subunit (basic helix-loop-helix transcription factor); IFITM1-3, Interferon-induced transmembrane protein 1, 2 and 3; IL12R, Interleukin 12 receptor; IL13R1, Interleukin 13 receptor 1, LYN, v-yes-1 Yamaguchi sarcoma viral related oncogene homolog; MAFB, v-maf musculoaponeurotic fibrosarcoma oncogene homolog B (avian); RARA, retinoic acid receptor alpha subunit; SIGLEC10, sialic acid binding Ig-like lectin 10; SOD1, soluble superoxide dismutase 1.