{alpha}V{beta}3-integrin routes herpes simplex virus to an entry pathway dependent on cholesterol-rich lipid rafts and dynamin2.
HSVs enter cells in a receptor-dependent [nectin1 or herpesviruses entry mediator (HVEM)] fashion by fusion of the viral envelope with plasma membrane (neutral pH compartment), by endocytosis into neutral or acidic compartments, or by macropinocytosis/phagocytosis. The cellular determinants of the route of entry are unknown. Here, we asked what cellular factors determine the pathway of HSV entry. CHO cells lack β(3)-integrin and the respective α-subunits' heterodimers. We report that, in the absence of α(V)β(3)-integrin, HSV enters CHO-nectin1 cells through a pathway independent of cholesterol-rich rafts and dynamin2. In the presence of α(V)β(3)-integrin, HSV enters CHO-nectin1 cells through a pathway dependent on cholesterol-rich rafts and dynamin2. HSV enters J-nectin1 and 293T cells through a neutral compartment independent of cholesterol-rich rafts and dynamin2. α(V)β(3)-integrin overexpression in these cells modifies the route of entry to an acidic compartment dependent on cholesterol-rich rafts and dynamin2, hence similar to that in α(V)β(3)-integrin-positive CHO-nectin1 cells. In some cells, the diversion of entry from an integrin- and raft-independent pathway to an acidic compartment requiring cholesterol-rich lipids rafts and dynamin2 is irreversible. Indeed, HSV cannot infect CHO-nectin1-α(V)β(3) cells through any compartment when the αvβ3-integrin-dependent pathway is blocked by anti-integrin antibody, anti-dynamin2, or anti-acidification drugs. We conclude that the αvβ3-integrin is a determinant in the choice of HSV entry pathway into cells. Because the pathway dictated by αvβ3-integrin is through lipid rafts, the platforms for a number of Toll-like receptors, current findings raise the possibility that αvβ3-integrin acts as a sentinel of innate immunity.
Department of Experimental Pathology, Section on Microbiology and Virology, Alma Mater Studiorum, University of Bologna, 40126 Bologna, Italy.
Tatiana
T
Gianni
Valentina
V
Gatta
Gabriella
G
Campadelli-Fiume
D000818:Animals; D000906:Antibodies / Q000494:pharmacology; D016466:CHO Cells; D015815:Cell Adhesion Molecules / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D002784:Cholesterol / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D006224:Cricetinae; D003412:Cricetulus; D034285:Dynamin II / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D007113:Immunity, Innate / Q000187:drug effects / Q000502:physiology; D039302:Integrin alphaVbeta3 / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D021962:Membrane Microdomains / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D000075983:Nectins; D018139:Simplexvirus / Q000502:physiology*; D053586:Virus Internalization
D000906:Antibodies; D015815:Cell Adhesion Molecules; D039302:Integrin alphaVbeta3; C000619010:NECTIN1 protein, human; D000075983:Nectins; D002784:Cholesterol; D034285:Dynamin II