Vectors expressing SARS immunogens, compositions containing such vectors or expression products thereof, methods and assays for making and using

Inventors

Anderson, D. Karl • Holtz-Corris, Kathleen M. • Chubet, Rick • Adams, Daniel • Cox, Manon

Assignees

Protein Sciences Corp

Abstract

SARS (severe acute respiratory syndrome virus, a coronavirus) immunogens, antigens, or epitopes, nucleic acid molecules encoding such immunogens, antigens, or epitopes; vectors containing such nucleic acid molecules, e.g., viral vectors such as baculovirus vectors, DNA vectors, such as DNA plasmid vectors, e.g., DNA plasmids that express a nucleic acid molecule in a mammalian cell, uses for such immunogens, antigens or epitopes and vectors, e.g., as an active component immunogenic, immunological or vaccine compositions, or to generate antibodies, such as monoclonal antibodies, and methods for making, and using such immunogens, antigens or epitopes, vectors, antibodies, including in methods for eliciting an immunological or immunogenic or vaccine response, as well as in assays or diagnostic kits or methods, are discussed, as well as a seamless fusion of sequences in a plasmid or vector, e.g., a sequence encoding a leader sequence and a sequence encoding a protein, epitope or immunogen or antigen.

Core Innovation

The described invention provides recombinant baculovirus vectors that express a baculovirus signal peptide and a SARS S protein, with expression of the SARS S protein under control of a polyhedrin promoter. The vectors include an isolated nucleic acid encoding the baculovirus signal peptide and are configured for recombinantly expressing the SARS S protein.

The invention further provides a method for producing a biologically active, highly pure, recombinant SARS S protein. The method infects insect cells grown in serum-free media with a recombinant baculovirus comprising DNA coding for the SARS S protein so that the SARS S protein is expressed recombinantly, followed by culturing in serum-free media. The recombinant SARS S protein is purified to 95% or greater purity and is biologically active in that it agglutinates red blood cells.

Additionally, the invention describes a method for preparing a baculovirus transfer vector to prepare a recombinant baculovirus that expresses a heterologous protein and a baculovirus signal peptide. In this transfer vector method, DNA coding for the heterologous protein is seamlessly joined to DNA coding for the baculovirus signal peptide without addition of a single nucleotide, thereby avoiding intervening nucleic acid molecules between the leader sequence and the DNA encoding the heterologous protein.

Claims Coverage

The document includes four independent claims covering a recombinant baculovirus vector for SARS S expression, a recombinant baculovirus vector comprising a specified signal-peptide encoding nucleic acid, a method for producing a biologically active, highly pure recombinant SARS S protein, and a transfer-vector preparation method that creates seamless joining without added nucleotides. The inventive features center on the SARS S expression system, production, purity, and activity of the SARS S protein, and seamless leader-to-antigen joining in transfer-vector construction.

Across the independent claims, the core inventive coverage is the recombinant baculovirus expression architecture for SARS S protein under a polyhedrin promoter using a baculovirus signal peptide, the production of a 95% or greater pure, biologically active SARS S protein that agglutinates red blood cells, and a transfer-vector construction approach that creates a seamless leader-to-antigen genetic join without added nucleotides.

Stated Advantages

Documented Applications