The present invention relates to an immunogen-carrier, wherein the immunogen-carrier is preferably a virus-like particle (VLP) composed of a plurality of a modified PCV2 ORF2 protein. In particular, the present invention belongs to the field of compliance markers and marker vaccines which allow for the differentiation between infected and vaccinated individuals. In particular, it relates to a compliance marker for vaccines including a subunit antigen, and a DIVA (Differentiating Infected from Vaccinated Animals) system which makes it possible to differentiate between animals infected with a pathogen and animals treated with a subunit antigen derived from said pathogen.

Disclosed are chimeric polypeptides based on viral membrane fusion proteins. More particularly, the present invention discloses chimeric polypeptides that comprise a virion surface exposed portion of a viral fusion protein and a heterologous structure-stabilizing moiety, and to complexes of those chimeric polypeptides. The present invention also discloses the use of these complexes in compositions and methods for eliciting an immune response to a fusion protein of an enveloped virus, or complex of the fusion protein, and/or for treating or preventing an enveloped virus infection. The present invention further discloses the use of the heterologous structure-stabilizing moiety for oligomerizing heterologous molecules of interest.

The invention provides isolated polynucleotide molecules that comprise a DNA sequence encoding an infectious RNA sequence encoding a genetically-modified North American PRRS virus, methods to make it and related polypeptides, polynucleotides, and various components. Vaccines comprising the genetically modified virus and polynucleotides and a diagnostic kit to distinguish between naturally infected and vaccinated animals are also provided.

The present disclosure provides an N protein epitope mutation marker for preparing an epitope deletion-marked vaccine strain of type II porcine reproductive and respiratory syndrome virus (PRRSV) and use thereof, belonging to the technical field of biological products. In the mutation marker, one or more amino acids are mutated based on an epitope sequence at positions 92 to 103 of a C-terminal of an N protein of the type II PRRSV; and the epitope mutation marker has an amino acid sequence shown in SEQ ID NO: 1, where X.sub.1 is selected from the group consisting of T, P, and A; and X.sub.2 is selected from the group consisting of V and A.

The present invention relates to a method for preparing cDNA infectious clones based on the genome of an attenuated Porcine Reproductive and Respiratory Syndrome virus (PRRSV) and uses thereof for preparing efficacious and safety-enhanced vaccines against PRRSV. The invention further comprises an infectious cDNA clone obtainable by such method. The invention further provides an attenuated modified PRRSV, and immunogenic compositions and vaccines comprising that attenuated PRRSV. The present invention further provides the attenuated PRRSV for use in the prophylaxis and/or the treatment of PRRSV infections, and the attenuated PRRSV for use as vaccine or medicament in the prophylaxis and/or the treatment of PRRSV infections.

A non-naturally occurring porcine reproductive and respiratory syndrome virus (PRRSV) is provided herein, and methods of making and using the non-naturally occurring PRRSV also are provided.

An expression cassette, wherein said expression cassette comprises: (a) an ie 1 promoter from white spot syndrome virus or a variant thereof; (b) a nucleic acid sequence encoding an N-terminal gp64 signal peptide or variant thereof, a nucleic acid sequence encoding an antigenic peptide, a nucleic acid encoding a transmembrane region, and a nucleic acid encoding a gp64 cytoplasmic region or variant thereof; in which the promoter is operably linked to the nucleic acid sequence.

The present invention relates to an immunogen-carrier, wherein the immunogen-carrier is preferably a virus-like particle (VLP) composed of a plurality of a modified PCV2 ORF2 protein. In particular, the present invention belongs to the field of compliance markers and marker vaccines which allow for the differentiation between infected and vaccinated individuals. In particular, it relates to a compliance marker for vaccines including a subunit antigen, and a DIVA (Differentiating Infected from Vaccinated Animals) system which makes it possible to differentiate between animals infected with a pathogen and animals treated with a subunit antigen derived from said pathogen.

Compounds useful as components of immunogenic compositions for the induction of an immunogenic response in a subject against infection, methods for their use in treatment, and processes for their manufacture are provided herein. The compounds comprise a nucleic acid construct comprising a sequence which encodes an interferon effector.

A non-naturally occurring porcine reproductive and respiratory syndrome virus (PRRSV) is provided herein, and methods of making and using the non-naturally occurring PRRSV also are provided.