Isolation of a heterogeneous population of temperature-sensitive mutants of measles virus from persistently infected human lymphoblastoid cell lines.

Abstract

Two human lymphoblastoid B-cell lines, WI-L2 and 8866, were infected with the Edmonston strain of measles virus at a multiplicity of infection of 10(-6), and stable persistent infections were established. By immunofluorescence and electron microscopy, the vast majority of cells from both cell lines were expressing viral antigens and releasing virion-like particles. However, very little infectious virus could be detected at 37 degrees C, either by an infectious centers assay or by titration of supernates from persistently infected cultures. When cultures were shifted to 31 degrees C, the cells released a population of virus that was temperature-sensitive. Clonal analysis of supernatant virus at 31 degrees C revealed a highly heterogeneous population of temperature-sensitive mutants, differing in plating efficiency ratios, thermolability, and antigen production at the nonpermissive temperature. Factors such as interferon, defective interfering particles, and extracellular virus do not appear to be important in maintaining the persistent carrier state. These studies have important implications for persistent infections of lymphoid cells in vivo, and the slow neurological diseases associated with measles, subacute sclerosing panencephalitis, and multiple sclerosis.

Measles virus from a long-term persistently infected human T lymphoblastoid cell line, in contrast to the cytocidal parental virus, establishes an immediate persistence in the original cell line

“…Thus, it has a miniplaque morphology on Vero cell monolayers and shows increased thermostability, as has been described for other MV infections (Ju et al, 1978). It shows no apparent cold sensitivity and only moderate thermosensitivity.…”

“…A number of possible mechanisms have been proposed for such viral infections; some refer to virus mutants (variants) produced during the infection, such as temperature-sensitive mutants (Ju et al, 1978;Youngner & Preble, 1980) or cold-sensitive mutants, as described for an SSPE-isolated MV (McKimm-Brechkin et al, 1982) and a persistently MVinfected mouse neuroblastoma (Rager-Zisman et al, 1984). Interference by defective virus has been described as one mechanism in the establishment and maintenance of persistent paramyxovirus infections (Roux & Holland, 1979;Rima et al, 1977).…”

Reversal of the measles virus-mediated increase of phosphorylating activity in persistently infected mouse neuroblastoma cells by anti-measles virus antibodies

“…Polyclonal anti-MV hyperimmune serum was raised in rabbits by immunization with antigen in complete Freund's adjuvant, followed by repeated intramuscular injections with solubilized virus alone (Ju et al, 1978). The preparation and characterization of monoclonal antibodies against measles virus N protein were described by Birrer et al (1981) and against H protein (NC32) by Carter et al (1983).…”

Lymphocyte function and virus infections.

“…Cell lines infected with measles virus produce a very heterogenous population of temperature-sensitive mutants of the virus with differing physical and antigenic properties (Ju et al, 1978). The implication of these observations is that in susceptible individuals measles infection may be followed by the persistent production and release of virus particles that have mutated from the original strain and against which the initial specific immune response would be ineffective.…”