Immunocytochemistry analysis of A431 cells labeling pan Cytokeratin with Mouse anti-pan Cytokeratin antibody (HA600134F) at 1/500 dilution. Cells were fixed in 4% paraformaldehyde for 15 minutes at room temperature, permeabilized with 0.1% Triton X-100 in PBS for 15 minutes at room temperature, then blocked with 1% BSA in 10% negative goat serum for 1 hour at room temperature. Cells were then incubated with Mouse anti-pan Cytokeratin antibody (HA600134F, iFluor™ 555) at 1/500 dilution in 1% BSA in PBST overnight at 4 ℃. PBS instead of the primary antibody was used as the secondary antibody only control. Nuclear DNA was labelled in blue with DAPI.