Identification of cell membrane protein as a receptor for hantaan virus

Abstract

The first event in viral infection of the host cell is binding of the virus to the cell surface. The cell-surface molecule with which the virus first specifically interacts or binds is called the virus receptor. This binding of the virus particle to the receptor involves numerous noncovalent interactions between the virion surface and the receptor, the sum of virus particle and a cell-surface molecule. Presumably, viruses have evolved to use receptors that are present on cells that have special features desired by the virus, either a permissive environment for its replication or a unique environment for a persistant infection. The basis of the cell and tissue tropisms of viruses is often related to the ability of the virus to bind a specific viral receptor. It has become clear that a virus-host binding can play an important role in determining the ultimate tropism of a virus. Compared with other members of Bunyaviridae family, the tropism of Hantaan virus is not clear yet. Although all of 12 different cell lines tested in these studies originated from different tissues and species, Hantaan virus was infected to the most of cell line. This suggested that Hantaan virus have a broad spectrum of tropism for species and organ. The pan-tropic pattern of Hantaan virus infection means that cellular receptor for Hantaan virus may be a common protein to a mammalian cell. There are several methods to identify a receptor for virus, classified by a manner to approach. A method using monoclonal antibody to protein assumed as receptor is easy to perform, but it is necessary to isolate and purify a receptor ultimately. We attempted to isolate and purify a putative receptor for Hantaan virus from cell membrane protein of cells. For this work, we determined Vero E6 cells capable of mass culture as target cell. To identify the molecules on cells which bind to Hantaan virus, VOPBA was performed with radiolabeled Hantaan virus. We found a 30-kDa protein that is putative receptor fo...