Increased Mobility and Redistribution of Concanavalin A Receptors on Cells infected with Newcastle Disease Virus

Abstract

CONCANAVALIN A (con A) and various other plant lectins have been used extensively to study differences in the organisation of the surface of normal and transformed cells^1–3. Cells transformed by oncogenic viruses are agglutinated by doses of con A which do not affect normal cells, but the latter can be made susceptible to agglutination by small doses of con A by brief trypsinisation. Furthermore, the susceptibility of normal cells to agglutination by con A can be increased by infection with various non-oncogenic enveloped viruses, including herpesviruses^4,5, poxviruses⁶, arboviruses⁷, paramyxoviruses^8,9 and rhabdoviruses⁹. The mechanism of this increased agglutinability is unknown. Since the glycoproteins in the envelope of such viruses can bind con A^9–11, their insertion into the plasma membrane of the infected cell during virus envelopment and release might increase the available con A receptors, which could account for the increased susceptibility to agglutination. We have detected no significant increase in con A receptors on cells infected with Newcastle disease virus (NDV) which were susceptible to agglutination by con A at concentrations that did not affect normal uninfected cells. We have found, however, that the increased agglutinability is due to a redistribution of con A receptors on the cell surface.