Abstract: Provided are modified arenaviruses and populations thereof, wherein the modified arenaviruses include i) an introduced PPXY domain; ii) an increased number of PPXY domains; iii) a substituted amino acid in place of S41 in a viral Z protein that is not a substrate for a serine or tyrosine kinase, or a combination of i)-iii). A PPXY domain can include a phosphomimetic replacement of the Y amino acid. Modified Old World and New World arenaviruses are included. Arenavirus production is provided using cell cultures that contain a kinase inhibitor that inhibits a kinase that can phosphorylate the Y amino acid of the PPXY domain, or by cells that have disrupted kinase gene expression, or by cells that have a disrupted ESCRT system. Also provided are pharmaceutical formulations that contain modified arenaviruses, and methods of using such formulations for stimulating an immune response hat is fully or partially protective against arenavirus infection.

Abstract: Provided are modified arenaviruses and populations thereof, wherein the modified arenaviruses include i) an introduced PPXY domain; ii) an increased number of PPXY domains; iii) a substituted amino acid in place of S41 in a viral Z protein that is not a substrate for a serine or tyrosine kinase, or a combination of i)-iii). A PPXY domain can include a phosphomimetic replacement of the Y amino acid. Modified Old World and New World arenaviruses are included. Arenavirus production is provided using cell cultures that contain a kinase inhibitor that inhibits a kinase that can phosphorylate the Y amino acid of the PPXY domain, or by cells that have disrupted kinase gene expression, or by cells that have a disrupted ESCRT system. Also provided are pharmaceutical formulations that contain modified arenaviruses, and methods of using such formulations for stimulating an immune response hat is fully or partially protective against arenavirus infection.