ABSTRACT
The potential application of dendritic cells (DC) sensitized with cytosine-phosphoric acid-guanine (CpG) oligodeoxynucleotide (ODN) and tumor antigen as a vaccine against murine melanoma was investigated with freshly isolated mouse bone marrow-derived dendritic cells. For the DC vaccine preparation, DC were sensitized with the B16 tumor antigen and CpG ODN was used to promote further maturation of the DC. The immunogenic activity of the vaccine was evaluated in vitro by determining the proliferation of T lymphocytes and the killing effect of cytotoxic T lymphocytes (CTL) on B16 tumor cells. The DC vaccine was injected intraperitoneally and tumor inhibition in mice bearing B16 xenografts was examined. All mice were cared for under an approved SIMM Institutional Animal Care and Use Committee (IACUC) protocol. In vitro, this DC vaccine promoted the proliferation of T lymphocytes and showed a potent killing effect on the target B16 cells. In vivo experiments showed that after treatment or pre-immunization both the tumor volume and weight were significantly decreased. The DC vaccine with CpG ODN and tumor antigen exhibited an inhibitory effect against melanoma, providing a potential method for melanoma cancer treatment.
ABSTRACT
To develop a cell-penetrating chimeric apoptotic peptide AVPI-LMWP/DNA co-delivery system for cancer therapy, we prepared the AVPI-LMWP/pTRAIL self-assembled complexes containing a therapeutic combination of peptide drug AVPI and DNA drug TRAIL. The chimeric apoptotic peptide AVPI-LMWP was synthesized using the standard solid-phase synthesis. The cationic AVPI-LMWP could condense pTRAIL by electrostatic interaction. The physical-chemical properties of the AVPI-LMWP/pTRAIL complexes were characterized. The cellular uptake efficiency and the inhibitory activity of the AVPI-LMWP/pTRAIL complexes on tumor cell were also performed. The results showed that the AVPI-LMWP/pTRAIL complexes were successfully prepared by co-incubation. With the increase of mass ratio (AVPI-LMWP/DNA), the particle size was decreased and the zeta potential had few change. Agarose gel electrophoresis showed that AVPI-LMWP could fully bind and condense pTRAIL at a mass ratio above 15:1. Cellular uptake efficiency was improved along with the increased ratio of W(AVPI-LMWP)/WpTRAIL. The in vitro cytotoxicity experiments demonstrated that the AVPI-LMWP/pTRAIL (W:W = 20:1) complexes was significantly more effective than the pTRAIL, AVPI-LMWP alone or LMWP/pTRAIL complexes on inhibition of HeLa cell growth. Our studies indicated that the AVPI-LMWP/pTRAIL co-delivery system could deliver plasmid into HeLa cell and induce tumor cell apoptosis efficiently, which showed its potential in cancer therapy using combination of apoptoic peptide and gene drugs.