Embodiments herein relate to compositions of and methods for live viruses. In certain embodiments, a live, attenuated virus composition includes, but is not limited to, one or more live, attenuated viruses and compositions to reduce inactivation and/or degradation of the live, attenuated virus. In other embodiments, the live, attenuated virus composition may be a vaccine composition. In yet other compositions, a live, attenuated virus composition may include at least one carbohydrate, at least one protein and at least one high molecular weight surfactants for reducing inactivation and/or degradation of the live, attenuated virus.

Modified influenza virus neuraminidases are described herein that improve viral replication, thus improving the yield of vaccine viruses. Expression of such modified neuraminidases by influenza virus may also stabilize co-expressed hemagglutinins so that the hemagglutinins do not undergo mutation.

Modified influenza virus neuraminidases are described herein that improve viral replication, thus improving the yield of vaccine viruses. Expression of such modified. neuraminidases by influenza virus may also stabilize co-expressed hemagglutinins so that the hemagglutinins do not undergo mutation.

The present invention relates to methods of replicating viruses in vitro. In particular, the invention relates to a genetically modified population of cells, and/or a population of cells treated with an exogenous compound, wherein the cells are capable of producing more virus than cells lacking the genetic modification and/or lacking treatment with the exogenous compound. The invention also relates to methods of producing populations of such cells, as well as the use of the viruses obtained to prepare vaccine compositions.

Provided is a method of producing reassortant influenza virus containing an antigenic protein of the first influenza virus strain, the method including the following steps: 1) a step of irradiating the first influenza virus strain with ultraviolet light in such an irradiation dose that the first influenza virus strain has initial infection ability and loses or is reduced in virus growth potential; 2) a step of infecting a host with the first influenza virus strain and the second influenza virus strain; 3) a step of culturing the host infected with the first influenza virus strain and the second influenza virus strain, to obtain culture product; 4) a step of inactivating influenza virus strain having an antigenic protein of the second influenza virus strain in the culture product obtained in the step 3); and 5) a step of collecting reassortant influenza virus after the step 4).

The present invention relates to a nucleic acid construct, a recombinant multiply-defective influenza virus, that promotes expression of an immunomodulatory protein in a host. This is applicable to the development of vaccines against infectious diseases, particularly those caused by influenza virus and Coronavirus.

Modified influenza virus neuraminidases are described herein that improve viral replication, thus improving the yield of vaccine viruses. Expression of such modified neuraminidases by influenza virus may also stabilize co-expressed hemagglutinins so that the hemagglutinins do not undergo mutation or decrease the need for HA binding to cells.

The present invention relates to methods of replicating viruses in vitro. In particular, the invention relates to a genetically modified population of cells, and/or a population of cells treated with an exogenous compound, wherein the cells are capable of producing more virus than cells lacking the genetic modification and/or lacking treatment with the exogenous compound. The invention also relates to methods of producing populations of such cells, as well as the use of the viruses obtained to prepare vaccine compositions.

A number of improvements for preparing vaccine antigens from disintegrated influenza viruses are disclosed. A splitting step can be followed by detergent exchange. Splitting can take place in the presence of a buffer with a higher ionic strength and/or in the presence of phosphate buffer.

The present invention relates to a method for stabilising viruses or bacteria, the method comprising embedding the viruses or bacteria in an aqueous solution, wherein the solution comprises: (i) at least three different amino acids; or (ii) at least one dipeptide or tripeptide and wherein the solution is free or substantially free of sugar(s), silanes and protein(s).