WT1 and focal segmental glomerulosclerosis: Recently, an immunohistochemical analysis (CD10, WT-1, Vimentin, Synaptopodin, α-actinin-4, GLEPP-1, cytokeratin (CK) 8-18, CK19, and Ki-67) of 131 renal biopsies with a diagnosis of primary FSGS classified according to the Columbia criteria was performed [42].