Ritzel et al. compared the properties of microglia and blood-derived monocytes (CD11b+, CD45+, LyC6 high expression (LyC6high)) after ischemic stroke caused by middle cerebral artery occlusion (MCAO) by using flow cytometry, which can separate the two cell types on the basis of their CD45 expression level [40]. The gene discussed is PTPRC; the disease is ischemic stroke.