title: RNA tumor virus-like particles in human fetal thymus cells stimulated by human B-cells.
abstract: Human fetal thymuses were investigated in a search for retroviruses. By electron microscopy, retrovirus-like particles were detected in the thymus cells only when they were cocultured with mitomycin C-treated human B-cells. Reverse transcriptase activity in the culture medium was found at a density of 1.15-1.17 g/cm3 in sucrose density gradients.
mesh_terms: D001402:B-Lymphocytes / Q000276:immunology*; D002478:Cells, Cultured; D003470:Culture Media; D005333:Fetus; D006801:Humans; D008213:Lymphocyte Activation; D016685:Mitomycin; D008937:Mitomycins / Q000494:pharmacology; D012194:RNA-Directed DNA Polymerase / Q000032:analysis; D012190:Retroviridae / Q000201:enzymology / Q000254:growth & development* / Q000648:ultrastructure; D013601:T-Lymphocytes / Q000201:enzymology / Q000276:immunology / Q000382:microbiology*; D014771:Virion / Q000201:enzymology / Q000254:growth & development* / Q000648:ultrastructure; D014775:Virus Activation
chemical_list: D003470:Culture Media; D008937:Mitomycins; D016685:Mitomycin; D012194:RNA-Directed DNA Polymerase