Methods of producing a pathogen with reduced replicative fitness are disclosed, as are attenuated pathogens produced using the methods. In particular examples, the method includes deoptimizing one or more codons in a coding sequence, thereby reducing the replicative fitness of the pathogen. Methods of using the attenuated pathogens as immunogenic compositions are also disclosed.

Methods of producing a pathogen with reduced replicative fitness are disclosed, as are attenuated pathogens produced using the methods. In particular examples, the method includes deoptimizing one or more codons in a coding sequence, thereby reducing the replicative fitness of the pathogen. Methods of using the attenuated pathogens as immunogenic compositions are also disclosed.

Disclosed herein are recombinantly engineered influenza viruses and compositions thereof.

The present invention relates to the field of medicine and virology. An attenuated influenza A virus, an influenza virus vector based thereon, and a pharmaceutical composition comprising thereof are provided, which can be used for the prevention and/or treatment of an infectious disease. In addition, the present invention relates to an attenuated influenza A virus, an influenza virus vector based thereon, and a pharmaceutical composition comprising thereof, which can be used for the treatment of oncological diseases.

Provided herein are attenuated influenza viruses and methods of making attenuated influenza viruses.

A recombinant virus containing a degron, a preparation method therefor, and an application thereof. At least one viral protein of the recombinant virus containing the degron contains at least one degron capable of being recognized by a protein degradation system of a host cell, wherein the degron comprises any one of or a combination of at least two of an amino acid sequence, a polypeptide, or a structural motif. Further provided are a nucleic acid molecule, a recombinant vector, a preparation method for the recombinant virus containing the degron, a preparation system for the recombinant virus containing the degron, a vaccine, an oncolytic virus, and a drug. The recombinant virus containing the degron can be recognized and degraded by the protein degradation system in the host cell, the replication capability is weakened or even removed, and after a corresponding vaccine, oncolytic virus or drug is prepared, a good effect and practical application value are achieved.

This disclosure provides live, attenuated viruses, and methods of making and using the live, attenuated viruses.

This disclosure provides attenuated swine influenza strains, particularly those produced via a reverse genetics approach, compositions comprising same, and methods of production and use thereof.

The present disclosure relates to an attenuation method of an influenza virus, an attenuated influenza virus strain, and the use thereof, and belongs to the technical field of biomedicine. The attenuation method of the present disclosure includes the following step: deleting a random number of bases at a random position for a transmembrane domain and a cytoplasmic domain of an M2 protein in a conserved region of the influenza virus to obtain an attenuated influenza virus with a corresponding base deletion. An attenuated influenza virus strain prepared by the attenuation method of the present disclosure exhibits prominent growth characteristics on an M2 protein-expressing MDCK cell line; and the virus strain at a high dose can grow in an MDCK cell or a chicken embryo and has a high agglutination titer of chicken red blood cells (CRBCs). Results of intranasal immunization of Balb/C mice show that the virus strain is non-pathogenic to mice compared with the parental virus IAV PR8. The random base deletion of the present disclosure reduces the virulence of the influenza virus and lays a foundation for the screening of safe and effective influenza A virus (IAV) live-attenuated vaccines.

Disclosed herein are compositions and methods related to mutant viruses, and in particular, mutant influenza viruses. The mutant viruses disclosed herein include a mutant M2 sequence, and are useful in immunogenic compositions, e.g., as vaccines. Also disclosed herein are methods, compositions and cells for propagating the viral mutants, and methods, devices and compositions related to vaccination.