Developing a Vaccine to Block West Nile Virus Transmission: In Silico Studies, Molecular Characterization, Expression, and Blocking Activity of Culex pipiens mosGCTL-1

Abstract

Background: Mosquito galactose-specific C-type lectins (mosGCTLs), such as mosGCTL-1, act as ligands to facilitate the invasion of flaviviruses like West Nile virus (WNV). WNV interacts with the mosGCTL-1 of Aedes aegypti (Culicidae) and facilitates the invasion of this virus. Nevertheless, there is no data about the role of mosGCTL-1 as a transmission-blocking vaccine candidate in Culex pipiens, the most abundant Culicinae mosquito in temperate regions. Methods: Adult female Cx. pipiens mosquitoes were experimentally infected with a WNV infectious blood meal, and the effect of rabbit anti-rmosGCTL-1 antibodies on virus replication was evaluated. Additionally, in silico studies such as the prediction of protein structure, homology modeling, and molecular interactions were carried out. Results: We showed a 30% blocking activity of Cx. pipiens mosGCTL-1 polyclonal antibodies (compared to the 10% in the control group) with a decrease in infection rates in mosquitoes at day 5 post-infection, suggesting that there may be other proteins in the midgut of Cx. pipiens that could act as cooperative-receptors for WNV. In addition, docking results revealed that WNV binds with high affinity, to the Culex mosquito lectin receptors. Conclusions: Our results do not support the idea that mosGCTL-1 of Cx. pipiens primarily interacts with WNV to promote viral infection, suggesting that other mosGCTLs may act as primary infection factors in Cx. pipiens.

Recognition of Arboviruses by the Mosquito Immune System

“…quinquefasciatus mosGCTL-1 homolog was seen [172]. However, a more recent study failed to interfere with WNV infection using anti-mosGCTL-1 antibodies in Culex pipiens [174]. Additional mosCTLs have been shown to bind the viral envelopes of DENV and JEV, promoting their entry into mosquito cells [175,176].…”