Compositions, methods, and uses of recombinant nucleic acids to elicit Th1- or Th2-biased immune responses in an individual are presented. In some embodiments, the nucleic acid includes a first nucleic acid segment encoding a MHC-II trafficking signal and a second nucleic acid segment encoding a polytope peptide and a Th1-specific polarizing epitope or a Th2-specific polarizing epitope. Optionally, the Th1-specific polarizing epitope or the Th2- specific polarizing epitope is part of the polytope peptide. The recombinant nucleic acid can be inserted in a viral, bacterial, or yeast expression vector so that the recombinant protein encoded by the recombinant nucleic acid can be expressed in an antigen presenting cell of an individual to elicit Th1- or Th2-biased immune response in the individual.