title: Internalization of human rhinovirus 14 into HeLa and ICAM-1-transfected BHK cells.
abstract: Virus adsorption and uptake of human rhinovirus 14 (HRV14) were studied with HeLa cells and baby hamster kidney (BHK) cells which were transfected with the HRV14 receptor intercellular adhesion molecule-1 (ICAM-1). Transmission electron microscopy of HeLa cells revealed that HRV14 was internalized via clathrin-coated pits and -coated vesicles. A minority of virus particles also used uncoated vesicles for entry. The internalization showed the characteristics of receptor-mediated endocytosis. Presence of the carboxylic ionophore monensin inhibited viral uncoating, indicating a pH-dependent entry mechanism. The expression of ICAM-1 on the surface of the ICAM-1 transfected baby hamster kidney cells (BHK-ICAM cells) allowed extensive virus adsorption and internalization through membrane channels. Virus particles were lined up in these channels like pearls on a string, but did not induce a productive infection. Although ICAM-1 was expressed to the same degree on BHK-ICAM and HeLa cells, HRV14 induced neither viral protein and RNA syntheses nor infectious virus progeny in BHK-ICAM cells. ICAM-1 on the transfected BHK cells was a functional active receptor as it rendered these cells permissive to coxsackievirus A21. These results suggest that HRV14 uptake into BHK-ICAM cells is blocked directly in or shortly after its final step of internalization, the uncoating. Our findings underline that the receptor ICAM-1 determines virus uptake into cells, however, is not sufficient to confer susceptibility of BHK cells to HRV14 infection.
authors.affiliation: Institut für Klinische und Experimentelle Virologie, Universitätsklinikum Benjamin Franklin, Freie Universität Berlin, Germany.
authors.forename: H P
authors.initials: HP
authors.lastname: Grunert
authors.forename: K U
authors.initials: KU
authors.lastname: Wolf
authors.forename: K D
authors.initials: KD
authors.lastname: Langner
authors.forename: D
authors.initials: D
authors.lastname: Sawitzky
authors.forename: K O
authors.initials: KO
authors.lastname: Habermehl
authors.forename: H
authors.initials: H
authors.lastname: Zeichhardt
mesh_terms: D000818:Animals; D006224:Cricetinae; D006367:HeLa Cells / Q000821:virology; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000235:genetics / Q000502:physiology*; D007668:Kidney / Q000821:virology; D012229:Rhinovirus / Q000502:physiology*; D014162:Transfection; D014764:Viral Proteins / Q000096:biosynthesis
chemical_list: D014764:Viral Proteins; D018799:Intercellular Adhesion Molecule-1