M2-DEFECTIVE POXVIRUS Russian patent published in 2024 - IPC C12N15/863 A61K39/275 C12N7/00 

FIELD: biotechnology.

SUBSTANCE: described is a modified poxvirus for stimulating or improving the immune response. Genome of modified poxvirus contains in native (wild type) context M2L locus coding functional poxvirus protein m2, and which is modified so as to be defective with respect to said m2 function; wherein said functional poxviral protein M2 can bind co-stimulating ligands CD80 or CD86 or both co-stimulating ligands CD80 and CD86, and wherein said defective m2 function cannot bind said co-stimulating ligands CD80 and CD86. Also described is a method of producing modified poxvirus, which includes the following steps: a) obtaining a producer cell line, b) performing transfection or infection of the obtained producer cell line with a modified poxvirus, c) culturing a line of transfected or infected producer cells in suitable conditions so as to ensure production of a virus, d) recovering the obtained virus from the culture of said producer cell line and, optionally, e) purification of said isolated virus. Disclosed is a composition for stimulating or improving the immune response, containing a therapeutically effective amount of a modified poxvirus and a pharmaceutically acceptable carrier. Disclosed is the use of the composition for treating or preventing a proliferative disease selected from a group consisting of cancerous diseases.

EFFECT: m2-defective poxviruses are especially useful for the expression of immunomodulatory polypeptides, such as anti-CTLA-4 antibodies, in order to stimulate or improve the immune response.

38 cl, 13 dwg, 1 tbl, 5 ex