Colocalization of APOL1 with renal cell marker proteins in non-diseased adult kidney cryo-sections from a European American. Kidney cryo-sections were stained for APOL1 (red), the indicated cell marker proteins (green) and counterstained with DAPI. APOL1 colocalizes with SYNPO (podocyte marker) positive cells; APOL1 does not colocalize with CD31 (endothelial cell marker) positive cells; APOL1 is not enriched in DPP4 (proximal tubule cell membrane marker) positive cells; APOL1 signal does not overlap with αSMA (mesangial cell marker) positive cells. SYNPO, synaptopodin; DPP4, dipeptidyl peptidase 4; αSMA, alpha-smooth muscle actin. (All ×400). Lijun Ma and Barry Freedman, Wake Forest School of Medicine, Winston-Salem, North Carolina