Expression, Purification, and Characterization of Bovine Leukemia Virus-Like Particles Produced in Drosophila S2 Cells

Bovine leukemia virus (BLV) is an oncogenic deltaretrovirus that infects cattle worldwide. In Uruguay, it estimated more than 70% of dairy are infected, causing serious economic losses due to decreased milk production, increased calving interval, and livestock lymphosarcoma. Several attempts develop vaccine candidates activate protective immune responses against BLV were performed, but up date, there no ensures efficient protection and/or viral transmission. The development application new vaccines effectively control infection represent a major challenge for countries with high prevalence infection. this study, we generated two Drosophila melanogaster S2 stable cell lines capable producing virus-like particles (BLV-VLPs). One them, BLV-VLP1, expressed both Gag Env wild-type (Envwt) full-length proteins, whereas BLV-VLP2 contain together mutant form non-susceptible proteolytic maturation by cellular furin type enzymes (EnvFm). We showed Envwt properly cleaved furin, EnvFm produced as gp72 precursor, which undergoes some partial cleavage. observed said mutation does not drastically affect its expression or entry into the secretory pathway insect cells. addition, on membrane retains significant structural motifs when in Morphology size purified BLV-VLPs analyzed transmission electron microscopy dynamic light scattering, showing numerous non-aggregated approximately spherical variable diameter (70–200 nm) previously reported retroviral VLPs using different systems. Furthermore, identified N-glycosylation patterns rich mannose protein displayed VLP2. Our results suggest cells could be potential immunogen used might contribute, conjunction other strategies, reduce virus.