Recombinant Protein Production using a Mammalian Unconventional Secretory Pathway

Abstract

Recombinant proteins are widely used throughout biomedical research, and the expansive and diversified usage of such reagents requires continued development of novel production processes. Unconventional protein secretion might offer a unique solution to some of the niche problems in traditional protein production systems, such as enabling the heterogeneous expression and secretion of functional bacterial proteins in mammalian cells. To investigate the feasibility of such a system, a panel of unconventionally secreted proteins was identified and used to compare their ability to induce secretion of GFP. Afterwards, IL-1β, an unconventionally-secreted proinflammatory cytokine, was identified and used to produce Streptococcus agalacticae Ig-degrading enzyme in HEK293 cells. The resulting protein was characterized and compared to a conventionally-secreted variant, where it exhibited increased activity.