A method is provided to improve virus production is an infected host cell by culturing the infected cell in an effective amount of alpha-ketoglutarate.

The present invention concerns a method for production of an active ingredient of a drug or diagnostic agent, in which (a) MDCK cells are infected with a virus; and (b) the MDCK cells are cultured in suspension culture on a commercial scale under conditions that permit multiplication of the viruses; in which culturing occurs in a volume of at least 30 L. The invention also concerns a method for production of a drug or diagnostic agent in which an active ingredient is produced according to the above method and mixed with an appropriate adjuvant, auxiliary, buffer, diluent or drug carrier.

The present invention discloses a type II Pseudorabies virus attenuated strain and its preparation method and application. The attenuated strain of pseudorabies virus is gE/TK-double-deficient strain, which is named as PRV-HD/c strain of PRV dual-deletion strain, and the accession number is CGMCC No. 14325. The attenuated strain of the pseudorabies virus of the present invention is obtained from the newly isolated strain of pseudorabies virus type II after deletion of the gE and TK double genes and has reduced pathogenicity and strong immunogenicity and is inactivated by the attenuated strain of pseudorabies virus vaccines or live attenuated vaccines, which can provide effective immunity to PRV susceptible animals such as pigs and mice.

The present invention discloses a type II Pseudorabies virus attenuated strain and its preparation method and application. The attenuated strain of pseudorabies virus is gE/TK-double-deficient strain, which is named as PRV-HD/c strain of PRV dual-deletion strain, and the accession number is CGMCC No. 14325. The attenuated strain of the pseudorabies virus of the present invention is obtained from the newly isolated strain of pseudorabies virus type II after deletion of the gE and TK double genes and has reduced pathogenicity and strong immunogenicity and is inactivated by the attenuated strain of pseudorabies virus vaccines or live attenuated vaccines, which can provide effective immunity to PRV susceptible animals such as pigs and mice.

The present disclosure provides a method to enhance the production of virus in cultured fibroblasts by supplementing the cells with a TCA cycle intermediate, aketoglutarate, or a derivative thereof, wherein virus production is enhanced compared to the same method canied out in the absence of a-ketoglutarate or the derivative thereof. In view of the art, the method provides an unexpected improvement on methods routinely practiced.

The present invention relates to a method to modify and/or to isolate exosomes and other naturally occurring plasma membrane derived microvesicles, by incubation with a reactant, consisting of at least a membrane anchor domain or moiety and a hydrophilic functional domain or moiety. The invention also relates to modification using the same of artificially-prepared lipid bilayer vesicles called liposomes (composed of natural phospholipids) and non-biological or synthetic block copolymer membrane mimics which also form vesicles in aqueous solution called polymersomes.

Disclosed are methods of treatment of a subject, such as a method of vaccination, immunomodulation or gene therapy of a subject. These methods comprise administering to the subject a modified enveloped viral particle, wherein the modified enveloped viral particle has been obtained by a method comprising the steps of a) incubating a fluid containing enveloped viral particles with one or more reactants consisting of a hydrophilic target domain and a lipophilic membrane anchor domain, wherein the lipophilic membrane anchor domain becomes integrated into the lipid double layer of the envelope of the viral particle, wherein the hydrophilic target domain becomes exposed to the fluid; and b) separating enveloped modified viral particles from excessive reactants.