Proteasome targeting of intrabodies was initially developed for HD by Butler et al. [13] using the ST14 cell model transiently transfected the mhttex1-72Q-GFP plus the huntingtin specific scFv intrabody anti-htt N17 C4-PEST to demonstrate reduction of cellular toxicity in a flow cytometry assay. This evidence concerns the gene HTT and Huntington disease.