Figure 3.

Summary of evidence from different genetic profiling strategies for the existence of a genetically distinct intermediate monocyte subset with reference to studies performed since the development of consensus nomenclature in 2010. Several studies using gene expression analyses of sorted populations have confirmed genetic distinctions between the three populations. Profiling of transcription and enhancer activity and of miRNA profiles has further added to these data. Single cell analyses of gene expression have also generally supported the existence of three monocyte subsets although results from Zillionis et al. (70) suggest the third identified population may represent a subpopulation of classical monocytes. The three monocyte subsets also remain genetically distinct after stimulation with bacterial or viral agonists. mRNA, messenger RNA; NF-κB, Nuclear Factor κB; mi-RNA, micro-RNA.