Compositions and methods for identifying antigens which elicit an immune response

An expression vector comprising a polynucleotide promoter sequence, a polynucleotide encoding a signal sequence, a polynucleotide encoding an antigen, a polynucleotide encoding a cell binding element, and a polynucleotide polyadenylation sequence all operatively linked, wherein said antigen is MAGE-3 or a fragment thereof, and wherein said polynucleotide encoding a signal sequence is derived from human chemokine RANTES gene, and further wherein said a cell binding element is human IgG1a or a fragment thereof.

A fusion protein comprising an antigen and a cell binding element encoded by an expression vector, wherein said expression vector comprises a polynucleotide promoter sequence, a polynucleotide encoding a signal sequence, a polynucleotide encoding an antigen, a polynucleotide encoding a cell binding element, and a polynucleotide polyadenylation sequence all operatively linked, wherein said antigen is MAGE-3 or a fragment thereof, and wherein said polynucleotide encoding a signal sequence is derived from human chemokine RANTES gene, and further wherein said a cell binding element is human IgG1a or a fragment thereof.

A method of producing a vaccine, said method comprising the steps of:

• transfecting an antigen presenting cell with an expression vector, wherein said expression vector comprises a polynucleotide promoter sequence, a polynucleotide encoding a signal sequence, a polynucleotide encoding an antigen, a polynucleotide encoding a cell binding element, and a polynucleotide polyadenylation sequence all operatively linked, wherein said antigen is MAGE-3 or a fragment thereof, and wherein said polynucleotide encoding a signal sequence is derived from human chemokine RANTES gene, and further wherein said a cell binding element is human IgG1a or a fragment thereof;
• and
• expressing said vector to produce an antigen under conditions wherein said antigen is secreted from said antigen presenting cell.

A method of eliciting an immune response in a mammal directed against an antigen, said method comprising:

• introducing an expression vector into a first cell, wherein said expression vector comprises a polynucleotide promoter sequence, a polynucleotide encoding a signal sequence, a polynucleotide encoding an antigen, a polynucleotide encoding a cell binding element, and a polynucleotide polyadenylation sequence all operatively linked, wherein said antigen is MAGE-3 or a fragment thereof, and wherein said polynucleotide encoding a signal sequence is derived from human chemokine RANTES gene, and further wherein said a cell binding element is human IgG1a or a fragment thereof;
• and
• administering said first cell to said mammal, wherein said first cell expresses said expression vector to produce said antigen, wherein said antigen is secreted from said first cell and is endocytosed into said first cell or a second cell, wherein said endocytosed antigen is processed in said first cell or second cell, and said processed antigen elicits an immune response in said mammal.