title: Reverse transcriptase activity and particles of retroviral density in cultured canine lymphosarcoma supernatants.
abstract: Lymphoid tissue from 43 cases of canine lymphosarcoma and from 40 clinically normal dogs have been examined for markers of retrovirus infection. From 69-76% of culture supernatants from lymphosarcomas were shown to contain particles of retroviral density and to possess poly rC-oligo dG templated polymerase (reverse transcriptase) activity compared with 17-24% of culture supernatants from normal canine lymphoid cells. In 6 culture supernatants from cases of lymphosarcoma, high molecular weight 60-70S RNA was detected and shown to be found in association with this particulate reverse transcriptase activity. No such RNA was detected in 6 culture supernatants from normal canine lymphoid cells.
mesh_terms: D000818:Animals; D002499:Centrifugation, Density Gradient; D004283:Dog Diseases / Q000201:enzymology* / Q000382:microbiology; D004285:Dogs; D005260:Female; D008198:Lymph Nodes / Q000201:enzymology / Q000382:microbiology; D008228:Lymphoma, Non-Hodgkin / Q000201:enzymology / Q000382:microbiology / Q000662:veterinary*; D008297:Male; D012334:RNA, Neoplasm / Q000032:analysis; D012194:RNA-Directed DNA Polymerase / Q000378:metabolism*; D012190:Retroviridae / Q000302:isolation & purification*
chemical_list: D012334:RNA, Neoplasm; D012194:RNA-Directed DNA Polymerase