title: Measles virus strain-dependent variation in outcome of infection of human blood mononuclear cells.
abstract: Eight measles virus strains including four subacute sclerosing panencephalitis (SSPE) isolates were compared on the basis of their growth characteristics in human peripheral blood mononuclear cells and effect on mitogen-stimulated lymphocyte proliferation. The Edmonston strain virus and some other strains of measles virus replicated in phytohaemagglutinin (PHA)-stimulated lymphocytes and released high titres of infectious virus into the culture medium. Inhibition of DNA synthesis was relatively low at the beginning of lymphocyte proliferation and could be detected only at high multiplicity of infection. Three to 4 days after initiation of proliferation a strong inhibition was seen also in cultures infected with low doses of virus, and was apparently related to the production of high titres of new infectious virus. Some virus strains originally isolated from SSPE patients produced only a small amount of infectious virus in lymphocytes at 37 degrees C but had a very strong inhibitory effect on lymphocyte proliferation leading to early cell death. The inhibitory effect was found over a wide range of virus concentrations, but was strictly dose-dependent and no increase in inhibition with low multiplicities of infection could be seen with longer culture times. The amount of interferon induced by different strains varied from 400 to 6400 international units/ml but the amount of interferon produced in the cultures did not correlate with the inhibitory effect on proliferation or with the amount of released new infectious virus. The Hallé measles strain, originally isolated from an SSPE patient, differed most from the Edmonston strain in its characteristics, and was studied in greater detail. Although only a small amount of infectious virus was produced, the Hallé strain had a very strong inhibiting effect on the proliferation of PHA-stimulated lymphocytes, and extensive syncytium formation was seen leading to cell death within 3 days.
mesh_terms: D000818:Animals; D002460:Cell Line; D004279:DNA, Viral / Q000096:biosynthesis; D006801:Humans; D007372:Interferons / Q000096:biosynthesis; D007700:Kinetics; D007963:Leukocytes, Mononuclear / Q000382:microbiology*; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000382:microbiology; D008459:Measles virus / Q000145:classification / Q000254:growth & development*; D013344:Subacute Sclerosing Panencephalitis / Q000382:microbiology*; D014709:Vero Cells
chemical_list: D004279:DNA, Viral; D007372:Interferons