Inhibition of Appearance of pH-Dependent Virus-Cell Fusion by Neutralizing Monoclonal Antibodies to Transmissible Gastroenteritis Virus

Abstract

Five MAbs, which showed neutralizing (NT) activity and recognized S (previously designated E2) glycoprotein of TGE virus TO-163, inhibited cell fusion by TGE virus in IB-RS-2 cells. Other S-specific MAbs with no NT activity did not inhibit the cell fusion. The results indicated that a neutralization epitope is same or very close to a fusion active site. The kinetics of membrane fusion following a reduction in pH were also investigated. The cell fusion appeared between 2 and 6 hr after the binding medium was added.