Production of Brazilian human norovirus VLPs and comparison of purification methods

Abstract

Noroviruses (NVs) are responsible for most cases of human nonbacterial gastroenteritis worldwide. Some parameters for the purification of NV virus-like particles (VLPs) such as ease of production and yield were studied for future development of vaccines and diagnostic tools. In this study, VLPs were produced by the expression of the VP1 and VP2 gene cassette of the Brazilian NV isolate, and two purification methods were compared: cesium chloride (CsCl) gradient centrifugation and ion-exchange chromatography (IEC). IEC produced more and purer VLPs of NV compared to CsCl gradient centrifugation.

Cell-free protein synthesis of norovirus virus-like particles

“…1 The rst and only HuNoV vaccine candidate under human clinical trial (developed by Takeda Pharmaceutical Co. Ltd 2 ) contains VLP antigens, which are particles that mimic the native protein capsid of HuNoV. Because HuNoVs could hardly replicate in traditional tissue culture, 3,4 several other cell-based expression systems have been used for the production of HuNoV-VLPs, including E. coli, 5 P. pastoris, 3 insect cells 6 and plants. 7,8 When using the E. coli-based expression system, a capsid protein of HuNoV-VLPs fused with GST (glutathione S-transferase) could only be synthesized at a yield of 1.5-3 mg L À1 , 5 which is too low to meet the demands of producing HuNoV-VLPs as vaccines.…”