title: Retrovirus produced by a lymphoid cell line from an infant with acute lymphoblastic leukemia.
abstract: A lymphoid cell line CK-a was established from peripheral blood of an infant with acute lymphoblastic leukemia of non-T, non-B cell type with mediastinal tumor. The CK-a cells were positive for surface immunoglobulins, Epstein-Barr virus-specific nuclear antigen, HLA-DR and Leu 12 antigens, and negative for sheep erythrocyte-rosette-receptor, and Leu 1, 2, 3 and 4 antigens. Budding particles were detected in electron micrographs of ultrathin sections of the CK-a cells. In the culture media of CK-a cells, particles with a buoyant density of 1.16 g/ml and labeled with [3H]uridine and [35S]methionine but not with [3H]thymidine were found to carry reverse transcriptase activity which preferred Mg2+ to Mn2+. Enveloped particles of 80 to 120 nm in diameter were detected in the fractions at 1.16 g/ml by electron microscopy. Thus, the particles had properties compatible with a definition of Retroviridae, and were tentatively named CK virus (CKV). The genome size of CKV RNA determined by agarose-acrylamide composite gel electrophoresis was 6.1 +/- 0.2 kb. Immune electroblotting assay detected antibody reactive with a CKV protein with a molecular weight of 67,000 in the serum of the patient, but not in sera of an adult T cell leukemia patient and healthy controls. No syncytia were formed by mixed cultures of CK-a and XC cells.
mesh_terms: D000914:Antibodies, Viral / Q000032:analysis; D002460:Cell Line; D003470:Culture Media; D004259:DNA-Directed DNA Polymerase / Q000032:analysis; D015480:Deltaretrovirus Antibodies; D004586:Electrophoresis; D005260:Female; D006801:Humans; D007223:Infant; D007945:Leukemia, Lymphoid / Q000276:immunology / Q000382:microbiology* / Q000473:pathology; D008854:Microscopy, Electron; D012367:RNA, Viral / Q000032:analysis; D012190:Retroviridae / Q000302:isolation & purification*; D012261:Ribonucleoproteins / Q000032:analysis
chemical_list: D000914:Antibodies, Viral; D003470:Culture Media; D015480:Deltaretrovirus Antibodies; D012367:RNA, Viral; D012261:Ribonucleoproteins; D004259:DNA-Directed DNA Polymerase