title: Detection of bovine leukaemia virus RNA sequences in non-cultivated peripheral lymphocytes by in situ hybridization with 3H-labelled viral cDNA.
abstract: Bovine leukaemia virus (BVL) in circulating lymphatic cells of the blood is repressed and has to be activated for its expression. After in situ hybridization of BLV-3HcDNA with a specific activity of 3.9 X 10 dpm/micrograms to noncultivated blood cells from 5 leukotic cattle, in 4 of these animals from 0.96% to 1.5% lymphocytes were found to contain BLV-specific RNA sequences. Non-hybridized lymphocytes as well as calf thymus cells, used as controls, gave only 0.47% and 0.39% labelled cells, respectively. After short-term cultivation of white blood cells from these leukotic animals the percentage of labelled cells increased. During the short-term cultivation the number of hybridizing cells from one and the same animal and from all animal, when compared with each other, varied to a high extent. The highest values of BLV-RNA sequences-containing cells from all 5 animals at different cultivation times were within the range of from 2.4 to 16.2%.
mesh_terms: D000818:Animals; D001483:Base Sequence; D002417:Cattle; D002478:Cells, Cultured; D004279:DNA, Viral / Q000032:analysis; D001909:Leukemia Virus, Bovine / Q000235:genetics*; D008214:Lymphocytes / Q000382:microbiology; D009693:Nucleic Acid Hybridization; D012367:RNA, Viral / Q000032:analysis*; D012190:Retroviridae / Q000235:genetics*
chemical_list: D004279:DNA, Viral; D012367:RNA, Viral