Pathway of rubella virus infectious entry into Vero cells

• Published in: Journal of general virology 1996-02, Vol.77 (2), p.303-308
• Main Authors: Petruzziello, Rosanna, Orsi, Nicola, Macchia, Stefania, Rieti, Sabrina, Frey, Teryl K, Mastromarino, Paola
• Format: Article
• Language: English
• Subjects: Ammonium Chloride - pharmacology; Animals; Cercopithecus aethiops; Chloroquine - pharmacology; Hydrogen-Ion Concentration; Methylamines - pharmacology; Monensin - pharmacology; rubella virus; Rubella virus - physiology; Transfection; Vero Cells
• ISSN: 0022-1317; 1465-2099
• DOI: 10.1099/0022-1317-77-2-303

1 Istituto Pasteur-Fondazione Cenci Bolognetti, Institute of Microbiology, School of Medicine, University ‘La Sapienza’, Piazzale Aldo Moro 5, I-00185 Rome, Italy and 2 Department of Biology, Georgia State University, Atlanta, Georgia 30302-4010, USA The mechanism and the kinetics of rubella virus (RV) penetration into Vero cells were studied. By using pronase or acid treatment to inactivate virus which had adsorbed to cell membrane but had not been internalized, it was found that a period of 7 h was required in order for all of the adsorbed virus to enter the host cells. Lysosomotropic agents (monensin, methylamine, ammonium chloride and chloroquine) were used to study the mechanism by which RV penetrates host cells. Virus replication was inhibited if treatment of cells with these compounds was performed for at least 9 h after infection. However, if extracellular adsorbed virions were eliminated by acid treatment following removal of the lysosomotropic compounds, RV replication was completely inhibited by treatment with these drugs for any time period after adsorption. This indicated that the prolonged period of treatment with these compounds necessary to inhibit virus replication is due to the slow rate of RV internalization. None of the compounds had any effect on infection initiated by transfection of RV RNA, confirming that these drugs were exerting their inhibitory activity at penetration. The inhibition of RV replication by lysosomotropic compounds indicates that RV penetrates host cells by the endosomal pathway. * Author for correspondence. Fax [phone]. Received 19 June 1995; accepted 6 October 1995.