RNA expression cassette and cells for making alphavirus particles

摘要

Strategies for increasing the productivity of alphavirus packaging cell lines and of reducing the possibility that replication competent virus may be generated during large scale production of recombinant alphavirus particles.

主权项

1. An RNA expression cassette comprising a first and second transcription unit, wherein:
(a) the first transcription unit comprises a first alphavirus subgenomic promoter operably linked to a first coding sequence which encodes a mutant capsid protein of a first alphavirus, but not a glycoprotein of the first alphavirus, wherein the mutant capsid protein has reduced autoproteolytic activity; (b) the second transcription unit comprises a second alphavirus subgenomic promoter operably linked to a second coding sequence which encodes non-structural proteins 1-4 of a second alphavirus,wherein the expression cassette enhances production of replicon particles while minimizing generation of replication competent viral particles (RCVs) when used in a suitable packaging cell line.