Adenovirus-mediated MUC1 gene transduction into human blood-derived dendritic cells

MUC1 protein is widely expressed on various human cancer cells and has a sp ecific highly glycosylated core structure with multiple tandem repeats, whi ch may include an immunogenic peptide sequence. The potency of MUC1 protein to induce human histocompatibility leukocyte antigen-class I-restricted cy totoxic T-lymphocyte (CTL) induction remains to be fully clarified in human beings. In the current study, we made MUC1-expressing human dendritic cell s (DCs) using recombinant adenovirus vector. Adenovirus vector plasmid cont aining human MUC1 cDNA, pAdHM4-MUC1 was constructed using in vitro ligation with a shuttle vector, pHMCMV5. Adenovirus vector expressing MUC1 was gene rated by the transfection of PacI-digested recombinant vector plasmid into 293 cells. Human blood DCs were obtained front 7-day culture of monocytes w ith recombinant human (rh) granulocyte-macrophage (GM) colony-stimulating f actor (CSF) and (rh)interleukin (IL)-4. Then, 1 x 10(6) DCs were incubated with viral supernatant at a multiplicity of infection of 200 for 24 It in t he presence of rhGM-CSF and rhIL-4. Flow cytometric analysis showed that 30 % to 40% of the transduced DCs expressed MUC1 proteins by contrast, nontran sduced or transduced DCs with mock virus expressed only small amounts of MU C1 protein. Adenovirus-mediated MUC1 gene transduction into DCs had no sign ificant effect on DC surface marker expressions or functions such as mixed leukocyte reaction. Furthermore, MUC1-specific CD8(+) CTLs could be induced from healthy donor blood lymphocytes using MUC1-expressing DCs as stimulat ors. These results suggested that MUC1 gene-transduced DCs are a functional and potent tool for triggering a CTL response against MUC1(+) cancer cells .