title: Measles virus superinfection immunity and receptor redistribution in persistently infected NT2 cells.
abstract: A recombinant measles virus (MV) expressing red fluorescent protein (MVDsRed1) was used to produce a persistently infected cell line (piNT2-MVDsRed1) from human neural precursor (NT2) cells. A similar cell line (piNT2-MVeGFP) was generated using a virus that expresses enhanced green fluorescent protein. Intracytoplasmic inclusions containing the viral nucleocapsid protein were evident in all cells and viral glycoproteins were present at the cell surface. Nevertheless, the cells did not release infectious virus nor did they fuse to generate syncytia. Uninfected NT2 cells express the MV receptor CD46 uniformly over their surface, whereas CD46 was present in cell surface aggregates in the piNT2 cells. There was no decrease in the overall amount of CD46 in piNT2 compared to NT2 cells. Cell-to-cell fusion was observed when piNT2 cells were overlaid onto confluent monolayers of MV receptor-positive cells, indicating that the viral glycoproteins were correctly folded and processed. Infectious virus was released from the underlying cells, indicating that persistence was not due to gross mutations in the virus genome. Persistently infected cells were superinfected with MV or canine distemper virus and cytopathic effects were not observed. However, mumps virus could readily infect the cells, indicating that superinfection immunity is not caused by general soluble antiviral factors. As MVeGFP and MVDsRed1 are antigenically indistinguishable but phenotypically distinct it was possible to use them to measure the degree of superinfection immunity in the absence of any cytopathic effect. Only small numbers of non-fusing green fluorescent piNT2-MVDsRed1 cells (1 : 300 000) were identified in which superinfecting MVeGFP entered, replicated and expressed its genes.
authors: School of Biology and Biochemistry, The Queen's University of Belfast, Belfast BT9 7BL, Northern Ireland, UK.
authors: Martin
authors: M
authors: Ludlow
authors: Molecular Pathology Laboratory, Royal Group of Hospitals Trust, Belfast BT12 6BL, Northern Ireland, UK.
authors: Stephen
authors: S
authors: McQuaid
authors: School of Medicine, The Queen's University of Belfast, Belfast BT9 7BL, Northern Ireland, UK.
authors: S Louise
authors: SL
authors: Cosby
authors: Molecular Medicine Program, Mayo Clinic, Guggenheim 18, Rochester, MN 55905, USA.
authors: Roberto
authors: R
authors: Cattaneo
authors: School of Biology and Biochemistry, The Queen's University of Belfast, Belfast BT9 7BL, Northern Ireland, UK.
authors: Bert K
authors: BK
authors: Rima
authors: School of Biology and Biochemistry, The Queen's University of Belfast, Belfast BT9 7BL, Northern Ireland, UK.
authors: W Paul
authors: WP
authors: Duprex
mesh_terms: D015703:Antigens, CD / Q000378:metabolism*; D002459:Cell Fusion; D045744:Cell Line, Tumor / Q000166:cytology / Q000378:metabolism / Q000821:virology; D006801:Humans; D008457:Measles / Q000378:metabolism / Q000821:virology*; D008459:Measles virus / Q000235:genetics / Q000276:immunology / Q000502:physiology*; D051916:Membrane Cofactor Protein; D008562:Membrane Glycoproteins / Q000378:metabolism*; D011940:Receptor Aggregation; D011991:Receptors, Virus / Q000378:metabolism*; D011995:Recombination, Genetic; D014779:Virus Replication
chemical_list: D015703:Antigens, CD; C497857:CD46 protein, human; D051916:Membrane Cofactor Protein; D008562:Membrane Glycoproteins; D011991:Receptors, Virus