Immunofluorescent analysis of Caspase cleaved Htt (green) in 293T cells transfected with an Htt23Q (left panel) and Htt148Q (right panel) stop constructs ending in amino acid 552. Formalin fixed cells were permeabilized with 0.1% Triton X-100 in TBS for 10 minutes at room temperature and blocked with 5% normal goat serum for 15 minutes at room temperature. Cells were probed with an Htt neo-epitope 552 polyclonal antibody (Product # PA1-003) at a dilution of 1:50 for at least 1 hour at room temperature, washed with PBS, and incubated with goat-anti-rabbit secondary antibody at room temperature. Nuclei (blue) were stained with Hoechst dye.