Vaccines and gene therapy compositions and methods of making and using the same

Abstract

Methods of inducing an immune response against an immunogen in an individual are disclosed. The methods comprise administering to the individual, one or more nucleic acid molecules that comprise a nucleotide sequence that encodes an immunogen and a nucleotide sequence that encodes an Major Histocompatibility Complex antigen. The nucleotide sequences that encode the immunogen and the Major Histocompatibility Complex antigen are expressed when taken up by cells of the individual and an immune response against the immunogen is induced in the individual. Methods of reducing rejection of unmatched donor cells, tissue or organ in an individual undergoing cell, tissue or organ transplantation are disclosed. The methods comprise administering to the individual, one or more nucleic acid molecules that comprise a nucleotide sequence that encodes a death signal or toxin and a nucleotide sequence that encodes a Major Histocompatibility Complex antigen that is matched to the donor cells, tissue or organ. The nucleotide sequences that encode the Major Histocompatibility Complex antigen and death signal or toxin are expressed when taken up by cells of the individual. T cell death through interaction with the death signal or toxin results in a reduction of rejection of unmatched donor cells, tissue or organ. Methods of reducing a dominant immune response in an individual and methods of expanding a subpopulation of T cells associated with a specific immune response are also described. Plasmids and compositions comprising plasmids useful for practicing the method are described.