Anti-tumor CTLs with a Lentivirus-transduced DC Vaccine

Mucin 1 (MUC1) is a type I transmembrance protein that consists of an extracellular domain containing a variable number of tandem repeats (VNTRs), a transmembrance domain and a cytoplasmic domain (Gendler., 2001; Schuman et al., 2005). The 20-amino acid sequence (GVTSAPDTRPAPGSTAPPAH) repeats of the VNTRs of MUC1 are heavily glycosylated (Gendler et al., 1995). While MUC1 is expressed at low levels on the apical surface of ductal epithelia cells in many organs, on tumor cells it is overexpressed, under-glycosylated and associated with loss of polarity (Croce et al., 2007; Seregni et al., 1997; Brockhausen et al., 1995). These characteristic changes of MUC1 exposes its protein backbone, thereby making the tumor vulnerable to the immune system. Therefore, MUC1 epitopes are considered potential antitumor targets. Previous studies have attempted to develop