The low-density lipoprotein receptor-related protein-1 is essential for Dengue virus infection

Abstract

Dengue virus (DENV) causes the most prevalent and rapidly spreading arboviral disease of humans. It enters human cells by receptor-mediated endocytosis. Numerous cell surface proteins have been proposed as DENV entry factors. Among these, the phosphatidylserine receptor TIM-1 is the only one known to mediate virus internalization. However, several cellular models lacking TIM-1 are permissive to DENV infection, suggesting that other receptors exist. Here we show that the Low-density lipoprotein receptor-related protein-1 (LRP1) binds DENV virions by interacting with the DIII of the viral envelope glycoprotein. DENV infection is effectively inhibited by the purified receptor at 5x10-8 mol/L and the interaction of the envelope protein with LRP1 is also blocked by a natural ligand of LRP1. Depletion of LRP1 causes 100-fold lower production of infectious virus than controls. Our results indicate that LRP1 is another DENV receptor thus, becoming an attractive target to evaluate for the development of effective antiviral drugs against DENV. Author summaryDengue virus (DENV) is a complex of four related viruses, recognized as serotypes, designated as DENV1-4. Any of the four DENV serotypes can cause a self-limited disease of mild flu-like symptoms known as dengue or its life threatening form, severe dengue, with hemorrhagic manifestations, organ impairment and shock. This disease is widely spread in tropical and sub-tropical areas worldwide, where the incidence of severe dengue has been increasing steadily. So far, efforts that target components of the viral replication machinery in order to develop a specific antiviral drug for dengue disease patients have failed. Thus, identifying the cell surface receptors used by DENV to enter host cells would provide a new molecular target to develop inhibitory drugs. Here, we evaluate the Low density lipoprotein receptor-related protein-1 (LRP1) as a putative DENV receptor. We present evidence demonstrating that LRP1 binds DENV through the viral envelope protein. We show that the production of infective virus is impaired on cells lacking LRP1, and that purified LRP1 is a potent blocker of DENV infection. These results are consistent with LRP1 playing an important role on DENV entry, making this receptor a molecule of interest on the investigation for medical treatments of dengue/severe dengue disease.