The invention relates to a recombinant measles virus expressing a heterologous amino acid sequence derived from an antigen of a determined RNA virus, said recombinant measles virus being capable of eliciting a humoral and/or cellular immune response against measles virus or against said RNA virus or against both measles virus and against said RNA virus. It also relates to the use of said recombinant measles virus for the preparation of immunogenic composition.

The invention relates to a recombinant measles virus expressing a heterologous amino acid sequence derived from an antigen of a determined RNA virus, said recombinant measles virus being capable of eliciting a humoral and/or cellular immune response against measles virus or against said RNA virus or against both measles virus and against said RNA virus. It also relates to the use of said recombinant measles virus for the preparation of immunogenic composition.

The invention relates to a recombinant measles virus expressing a heterologous amino acid sequence derived from an antigen of a determined RNA virus, said recombinant measles virus being capable of eliciting a humoral and/or cellular immune response against measles virus or against said RNA virus or against both measles virus and against said RNA virus. It also relates to the use of said recombinant measles virus for the preparation of immunogenic composition.

The invention relates to recombinant measles virus expressing Lassa virus polypeptides, and concerns in particular immunogenic LASV particles expressed by a measles virus and/or virus like particles (VLPs) that contain proteins of a Lassa virus. These particles are recombinant infectious particles able to replicate in a host after an administration. The invention provides means, in particular nucleic acid constructs, vectors, cells and rescue systems to produce these recombinant infectious particles. The invention also relates to the use of these recombinant infectious particles, in particular under the form of a composition, more particularly in a vaccine formulation, for the treatment or prevention of an infection by Lassa virus.

Described herein is a method of enhancing virus replication in permissive cells that express a receptor to FGF2 protein. The method includes administering FGF2 protein or a functional variant thereof and the virus to the permissive cells. An oncolytic virus having a genome that includes an open reading frame that encodes FGF2 protein or a functional variant thereof is also described.

The invention relates to a recombinant measles virus expressing a heterologous amino acid sequence derived from an antigen of a determined RNA virus, said recombinant measles virus being capable of eliciting a humoral and/or cellular immune response against measles virus or against said RNA virus or against both measles virus and against said RNA virus. It also relates to the use of said recombinant measles virus for the preparation of immunogenic composition.

The invention relates to a recombinant measles virus expressing a heterologous amino acid sequence derived from an antigen of a determined RNA virus, said recombinant measles virus being capable of eliciting a humoral and/or cellular immune response against measles virus or against said RNA virus or against both measles virus and against said RNA virus. It also relates to the use of said recombinant measles virus for the preparation of immunogenic composition.

The invention relates to recombinant measles virus expressing Lassa virus polypeptides, and concerns in particular immunogenic LASV particles expressed by a measles virus and/or virus like particles (VLPs) that contain proteins of a Lassa virus. These particles are recombinant infectious particles able to replicate in a host after an administration. The invention provides means, in particular nucleic acid constructs, vectors, cells and rescue systems to produce these recombinant infectious particles. The invention also relates to the use of these recombinant infectious particles, in particular under the form of a composition, more particularly in a vaccine formulation, for the treatment or prevention of an infection by Lassa virus.

The present disclosure provides a method of producing a negative-strand RNA virus vector. The present disclosure specifically provides a method of producing a negative-strand RNA virus vector in the presence of a PKR inhibitory factor.

The present invention provides a recombinant measles virus useful as a live vaccine against COVID-19 and a vector used for production of the recombinant measles virus. That is, the present invention relates to a recombinant measles virus having a gene encoding a protein of the coronavirus SARS-COV-2 inserted between the N gene region and the P gene region in a measles virus genome; the recombinant measles virus in which the protein is a spike protein of SARS-COV-2 or a partial protein thereof; and a DNA in which a gene encoding a protein of SARS-COV-2 is inserted in a region ranging from the 1,686th base to the 1,694th base of a base sequence set forth in SEQ ID NO: 2.