IC-Tagging methodology applied to the expression of viral glycoproteins and the difficult-to-express membrane-bound IGRP autoantigen

Abstract

We have previously developed a methodology to produce protein microspheres (MS) that can be loaded with proteins of interest in living cells through their C or N-terminal tagging with the so-called IC-Tag. The IC-Tagging method has many applications ranging from the production of immobilized enzymes for industrial use to the production of subunit vaccines due to its intrinsic adjuvancy. Here we show the adaptation of the IC-Tagging to work inside the endoplasmic reticulum and bacteria, allowing us to produce properly modified viral glycoproteins. Additionally, we were able to express the Islet-specific glucose-6-phosphatase catalytic subunit-related protein (IGRP), whose expression remained elusive to date possibly due to its toxicity when over-expressed. IGRP is an antigen of enormous pharmaceutical interest as it is specifically targeted during the autoimmune response taking place in both the Non-Obese Diabetic (NOD) mice and type 1 diabetes (T1D) patients leading to the destruction of insulin-producing beta cells.

Nanoparticle- and Microparticle-Based Vaccines against Orbiviruses of Veterinary Importance

“…Although the platform was originally developed in eukaryotic cells, wh of the muNS-MS range between 1 and 4 μm, it was also adapted to work in ba the spheres have a diameter of around 400 nm (nanospheres, muNS-N Therefore, this technology could also benefit from the capabilities of nanosiz optimize antigen uptake or prompt Th1 responses. In addition, the bacter easy to handle and cost-effective for protein production, adding vers methodology [100], and allows for the production of encapsulated protein for different uses [101]. Additionally, the IC-Tagging methodology was ada inside the endoplasmic reticulum (ER).…”

“…Therefore, this technology could also benefit from the capabilities of nanosize-particles to optimize antigen uptake or prompt Th1 responses. In addition, the bacterial version is easy to handle and cost-effective for protein production, adding versatility to the methodology [ 100 ], and allows for the production of encapsulated proteins or enzymes for different uses [ 101 ]. Additionally, the IC-Tagging methodology was adapted to work inside the endoplasmic reticulum (ER).…”

“…Additionally, the IC-Tagging methodology was adapted to work inside the endoplasmic reticulum (ER). By using the G glycoprotein of vesicular stomatitis virus (VSV) and protein Gn from Rift Valley fever virus (RVFV), it was demonstrated that fully glycosylated proteins can be loaded in ER muNS-MS, thus mimicking the surface of enveloped viruses [ 100 ].…”