betadex and Zika-Virus-Infection

Zika virus (ZIKV) is a flavivirus that is well known for the epidemic in the Americas in 2015 and 2016 in which microcephaly in newborns and other neurological complications were connected to ZIKV infection. Many aspects of the ZIKV viral life cycle, including binding and entry into the host cell, are still enigmatic. Based on the observation that CHO cells lack expression of the epidermal growth factor receptor (EGFR) and are not permissive for various ZIKV strains, the relevance of EGFR for the viral life cycle was analyzed. Infection of A549 cells by ZIKV leads to a rapid internalization of EGFR that colocalizes with the endosomal marker EEA1. Moreover, infection by different ZIKV strains is associated with an activation of EGFR and the subsequent activation of the mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) signaling cascade. However, treatment of the cells with methyl-β-cyclodextrin (MβCD), which on the one hand leads to an activation of EGFR but on the other hand prevents EGFR internalization, impairs ZIKV infection. Specific inhibition of EGFR or of the Ras-Raf-MEK-ERK signal transduction cascade hinders ZIKV infection by inhibition of ZIKV entry. In accordance with this, knockout of EGFR expression impedes ZIKV entry. In the case of an already established infection, inhibition of EGFR or of downstream signaling does not affect viral replication. Taken together, these data demonstrate the relevance of EGFR in the early stages of ZIKV infection and identify EGFR as a target for antiviral strategies.

Topics: A549 Cells; Animals; beta-Cyclodextrins; Cell Line; Chlorocebus aethiops; CHO Cells; Cricetulus; ErbB Receptors; Host Microbial Interactions; Humans; Life Cycle Stages; Signal Transduction; Vero Cells; Virus Internalization; Virus Replication; Zika Virus; Zika Virus Infection

When Zika virus emerged as a public health emergency there were no drugs or vaccines approved for its prevention or treatment. We used a high-throughput screen for Zika virus protease inhibitors to identify several inhibitors of Zika virus infection. We expressed the NS2B-NS3 Zika virus protease and conducted a biochemical screen for small-molecule inhibitors. A quantitative structure-activity relationship model was employed to virtually screen ∼138,000 compounds, which increased the identification of active compounds, while decreasing screening time and resources. Candidate inhibitors were validated in several viral infection assays. Small molecules with favorable clinical profiles, especially the five-lipoxygenase-activating protein inhibitor, MK-591, inhibited the Zika virus protease and infection in neural stem cells. Members of the tetracycline family of antibiotics were more potent inhibitors of Zika virus infection than the protease, suggesting they may have multiple mechanisms of action. The most potent tetracycline, methacycline, reduced the amount of Zika virus present in the brain and the severity of Zika virus-induced motor deficits in an immunocompetent mouse model. As Food and Drug Administration-approved drugs, the tetracyclines could be quickly translated to the clinic. The compounds identified through our screening paradigm have the potential to be used as prophylactics for patients traveling to endemic regions or for the treatment of the neurological complications of Zika virus infection.

Topics: Animals; Antiviral Agents; Artificial Intelligence; Chlorocebus aethiops; Disease Models, Animal; Drug Evaluation, Preclinical; High-Throughput Screening Assays; Immunocompetence; Inhibitory Concentration 50; Methacycline; Mice, Inbred C57BL; Protease Inhibitors; Quantitative Structure-Activity Relationship; Small Molecule Libraries; Vero Cells; Zika Virus; Zika Virus Infection