A DNA vaccine effective for eliciting an immune response against cells that present
a carcinoembryonic antigen (CEA) comprises a DNA operably encoding a CEA and a
DNA operably encoding a CD40 ligand, SEQ ID NO:1 and SEQ ID NO: 2, respectively,
or its homotrimer, CD40LT. The DNA vaccine can be incorporated in a delivery vector
such as an attenuated live bacterium or virus, or a liposome carrier. In a method
embodiment, the DNA vaccine is administered orally to a mammal, such as a human,
to elicit an immune response against CEA presenting cells such as colon cancer
cells. A preferred method embodiment includes the additional step of treating the
mammal with recombinant antibody fusion protein huKS1/4-IL2 to enhance the immune
response effectiveness of the vaccine.
