Nuclear Factor Fixation and Permeabilization Staining Protocol
Prepare target cells of interest and perform surface staining as described in BioLegend's Cell Surface Immunofluorescence Staining Protocol. 
Fix the cells with 1 ml/tube BioLegend's Nuclear Factor Fixation Buffer, at room temperature in the dark for 20 minutes.
Centrifuge at 250 x g for 5 minutes; discard supernatant.
Wash once with 1 ml Biolegend's Nuclear Factor Permeabilization Buffer (1x).
Resuspend cells in 1 ml BioLegend's Nuclear Factor Permabilization Buffer (1x), incubate at room temperature in the dark for 20 minutes, spin down cells and discard the supernatant; then resuspend the pellet in 100 ul of BioLegend's Nucelar Factor Permeabilization Buffer (1x).
Add appropriate amount of flurochrome-conjugated antibodies for nuclear target of interest, and incubate at room temperature in the dark for 30 minutes.
Wash twice with Cell Staining Buffer, and resuspend in 0.5 ml Cell Staining Buffer, then analyze with flow cytometer with appropriate instrument settings.
