The present invention relates to methods and kits for detecting in a sample the presence of a virus particle or a virus-like particle that has reverse transcriptase activity and methods for preparing a retroviral contaminant-free substance. An aspect of the present invention is a method for detecting the presence of a virus particle in a sample of a Virus-like Particle (VLP) drug substance comprising a step of performing PCR-based reverse transcriptase (PBRT) on a sample of the VLP drug substance that has been treated with a protease.

Provided herein are compositions, systems, and methods for delivering cargo to a target cell. The compositions, systems, and methods comprise one or more polynucleotides encoding one or more endogenous retroviral elements for forming a delivery vesicle and one or more capture moieties for packaging a cargo within the delivery vesicle. The one or more endogenous retroviral elements for forming a delivery vesicle may comprise two or more of a retroviral gag protein, a retroviral envelope protein, a retroviral reverse transcriptase or a combination thereof. The retroviral gag protein alone, the retroviral envelope protein alone, or both the retroviral gag protein and retroviral envelope protein may be endogenous.

Provided is a nucleic acid construct for expressing a gene of interest, the nucleic acid construct comprising, in order from 5′-terminus, each sequence of: (a) a 5′ long terminal repeat (LTR) sequence derived from a retrovirus; (b) a packaging signal sequence (IV) derived from a retrovirus; (c) a sequence or multiple cloning site of the gene of interest; (d) a post-transcriptional regulatory sequence (PRE); (e) an siRNA generating sequence which forms at least one stem-loop structure and in which RNA, which induces RNA interference in mammalian cells, is transcribed; and (f) a 3′ LTR sequence derived form a retrovirus.

The present invention relates to an adenoviral vector capable of encoding a virus-like particle (VLP), said VLP displaying an inactive immune-suppressive domain (ISD). The vaccine of the invention shows an improved immune response from either of both of the response pathways initiated by CD4 T cells or CD8 T cells.

The present invention relates to an adenoviral vector capable of encoding a virus-like particle (VLP), said VLP displaying an inactive immune-suppressive domain (ISD). The vaccine of the invention shows an improved immune response from either of both of the response pathways initiated by CD4 T cells or CD8 T cells.

Disclosed herein are virus-like particle (VLP)-based bivalent vaccine compositions. The compositions may comprise a spherical retroviral Group-specific Antigen (“Gag”) protein core and at least two Ebola glycoproteins. The at least two Ebola glycoproteins may be located at the exterior surface of the spherical Gag protein core, such that the VLP-based vaccine presents at least two Ebola glycoprotein antigens. In one aspect, the at least two Ebola glycoproteins are a Zaire (EBOV) glycoprotein, and a Sudan (SUDV) glycoprotein.

The present invention relates to an adenoviral vector capable of encoding a virus-like particle (VLP), said VLP displaying an inactive immune-suppressive domain (ISD). The vaccine of the invention shows an improved immune response from either of both of the response pathways initiated by CD4 T cells or CD8 T cells.

The present invention relates to a method of quantifying the amount of Mock Virus Particles (MVP) removed from a solution as a result of processing that solution through a purification technique. This method involves the steps of adding MVP to a solution, processing the solution through a purification technique, quantifying the amount of MVP removed from the solution. The present invention also relates to a kit that can be used in conjunction with the method. This kit will comprise at least one stock solution of MVP and at least one quantification solution.

The present invention relates to a virus-derived particle comprising one or more Cas protein(s), as well as to kits and methods using the same for altering a target nucleic acid.

The present invention relates to an adenoviral vector capable of encoding a virus-like particle (VLP), said VLP displaying an inactive immune-suppressive domain (ISD). The vaccine of the invention shows an improved immune response from either of both of the response pathways initiated by CD4 T cells or CD8 T cells.