AUTHOR=de Mello Renata Gois , Bernardino Thaissa Consoni , Guardalini Luis Giovani Oliveira , Astray Renato Mancini , Antoniazzi Marta Maria , Jared Simone Gonçalves Silva , Núñez Eutimio Gustavo Fernández , Jorge Soraia Attie Calil 

TITLE=Zika virus-like particles (VLPs) produced in insect cells

JOURNAL=Frontiers in Pharmacology

VOLUME=Volume 14 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2023.1181566

DOI=10.3389/fphar.2023.1181566

ISSN=1663-9812

ABSTRACT=The Zika virus (ZIKV) infections are a healthcare concern mostly in the Americas, Africa, and Asia but have increased its endemicity area beyond these geographical regions. Due to the advances in infections by ZIKV, it is imperative to develop diagnostic and preventive tools against this viral agent. Virus-like particles (VLPs) appear as a suitable approach for use as antiviral vaccines. In this work, a methodology was established to produce VLPs containing the structural proteins, C, prM, and E of ZIKV produced in insect cells using the gene expression system derived from baculovirus. The vector pFast- CprME -ZIKV was constructed containing the gene sequences of ZIKV structural proteins and it was used to generate the recombinant bacmids (Bac- CprME -ZIKV) through transformation into DH10BacTM cells. The Bac- CprME -ZIKV was transfected in Spodoptera frugiperda (Sf9) insect cells and batches of BV- CprME -ZIKV were obtained by infection assays using a multiplicity of infection of 2. The Sf9 cells were infected, and the supernatant was collected 96h post-infection. The expression of the CprME -ZIKV protein on the cell surface could be observed by immunochemical assays. To concentrate and purify VLPs, the sucrose and iodixanol gradients were evaluated, and the correct CprME -ZIKV proteins’ conformation was evaluated by the western blot assay. The VLPs were also analyzed and characterized by transmission electron microscopy. Spherical structures like the native ZIKV from 50 to 65 nm containing the CprME -ZIKV proteins on their surface were observed in micrographs. The results obtained can be useful in the development path for a vaccine candidate against ZIKV.