Fig 2: iMG cells expressed microglia-specific markers (TMEM119 and P2RY12) and other myeloid-specific markers. The expression of surface markers on the iMG cells and iMacs were performed by immunocytochemistry. Peripheral monocytes were incubated with GM-CSF (iMacs) for 5–7 days or cocktail of GM-CSF and IL-34 (iMG cells) for 10–14 days. Representative images of iMacs and iMG cells were shown. (A) iMG cells expressed unique microglial markers TMEM119 (b) and P2RY12 (d), which were absent from iMacs (a,c). (B) Myeloid lineage markers were expressed on both iMacs and iMG cells, such as Iba1 (a,b), PU.1 (c,d), CX3CR1 (e,f), and TREM2 (g,h). Images were captured at 40× with a scale representing 20 µm, where P2RY12, CX3CR1, and TREM2 were stained green, TMEM119, Iba1, and PU.1 were stained red. Cellular nuclei were stained blue with DAPI.